This document discusses the four main types of lubricants: solid, liquid, semi-solid, and gaseous. Solid lubricants are solids placed between bearing surfaces and rely on applied load for performance. Liquid lubricants include oils that can carry away heat. Semi-solid lubricants like grease contain oil and thickener and remain where applied. Gaseous lubricants like air or nitrogen allow for very thin film separation at high temperatures and speeds. Each type has advantages for different applications.
Lubricants are substances that reduce friction between moving parts. This document discusses the basic properties and types of lubricants. It defines lubricants as liquids or greases that decrease machine friction. It then covers key lubricant properties like viscosity, viscosity index, pour point, and flash point. Finally, it categorizes lubricants based on physical state, use, grade, and source; and discusses common additive types for mineral and synthetic lubricants.
Lubricants are fluids introduced between moving parts to reduce friction, heat, and wear. Lubrication functions include reducing friction, wear, corrosion, and improving machine efficiency. Good lubricants have high boiling points, viscosity, oxidation resistance and thermal stability. Lubrication types include thick film hydrodynamic, thin film boundary, and extreme pressure lubrication. Lubricants are classified as liquid, semi-solid, or solid and their properties like viscosity, viscosity index, and flash point determine their performance and applications.
Hydrodynamic lubrication By Khairul BasharKhairul Bashar
The document discusses hydrodynamic lubrication, which occurs when there is a thick film of fluid between moving surfaces so that contact does not occur. For hydrodynamic lubrication to happen, there needs to be sufficient speed difference between the surfaces to form an "oil wedge" and build up pressure in the fluid film from their relative motion. Reynolds' equation describes the relationship between pressure buildup, sliding speed, viscosity, and geometry of the hydrodynamic film. The document presents diagrams showing the velocity and pressure distributions in an inclined pad bearing under hydrodynamic lubrication conditions.
Lubricants contain base oils and additives, with additives ranging from 0.1-30% of the volume. Additives are used to enhance base oil properties, suppress undesirable properties, and impart new properties. They play important roles like enhancing oxidation resistance at high temperatures, avoiding failure from metal-to-metal contact, and ensuring flow at low temperatures. Common additive types include detergents, antioxidants, extreme pressure additives, and viscosity index improvers. Additives work by attaching to surfaces via polarity and forming protective films on metals. Too high of an additive concentration can degrade performance, and additives must be balanced to avoid competing effects. Trends include developing additives that improve performance while reducing environmental
This document discusses different types of lubrication used in mechanical systems. It describes boundary lubrication as metal-to-metal contact that occurs during startup. Hydrostatic lubrication uses an external pressure source to separate surfaces with a lubricant film. Hydrodynamic lubrication fully separates surfaces using hydraulic forces generated by fluid viscosity as surfaces move. Elastohydrodynamic lubrication involves rolling contact that elastically deforms surfaces to lubricate them. Mixed lubrication is a combination of boundary and hydrodynamic lubrication, where asperities still contact but surfaces are mostly separated. The Stribeck curve illustrates the relationship between friction and the lubrication regime from boundary to hydrodynamic.
The document discusses lubrication and its types. It defines lubrication as reducing wear between surfaces in contact by interposing a lubricant between them. Lubricants are classified based on their physical state. The main types of lubrication are hydrodynamic, hydrostatic, elastohydrodynamic, boundary, mixed, and extreme pressure lubrication. Each type is distinguished by the nature of motion and separation between surfaces, with hydrodynamic providing the greatest separation by a fluid film and boundary having the least separation with potential metal-to-metal contact. Proper lubrication reduces friction and wear, generates less heat, increases machinery life, and reduces energy consumption.
B.tech. ii engineering chemistry unit 3 A lubricantsRai University
This document discusses lubricants, which are substances that reduce friction between moving surfaces. It defines lubricants and describes their composition, functions, types, properties and applications. Lubricants typically contain 90% base oil and less than 10% additives. The key types of lubrication are thick film, thin film, and extreme pressure lubrication. Important lubricant properties include viscosity, flash point, and pour point. Common lubricants are used in the automotive, industrial, aviation and marine industries.
Diesel Engine Lubrication and Lube Oil Contamination ControlMd. Moynul Islam
This presentation is intended share knowledge specially about Diesel Engine Lubrication and How the Lube Oil get Contaminated and How to Control Contamination to protect Engine Components from damaging. Still the presentation is under development. Expecting suggestions/recommendations from viewers for further up gradation of this presentation.
The document discusses lubricant additives that are important components in engine oils beyond just the base oil. It explains that additives like dispersants, detergents, antiwear agents, and others are formulated to optimize performance across attributes like engine cleanliness, wear control, and fuel economy. Graphs and diagrams show how these additive molecules interact with surfaces and particles to inhibit aggregation and neutralize acids from engine blow-by. Selecting the right combination and amounts of additives is necessary to balance performance factors.
Types of Lubrication Used in I.C. EnginesHitesh Sharma
Lubricants are substances that reduce friction between surfaces in contact. There are different types of lubrication depending on the thickness of the lubricant film between surfaces - hydrodynamic lubrication occurs when a thick, continuous oil film separates surfaces, boundary lubrication involves a very thin film where metal-to-metal contact can happen, and hydrostatic lubrication uses external oil pressure rather than relative surface motion to separate surfaces with a complete oil film. Special additives are needed for extreme pressure lubrication under very high pressures and temperatures.
This document provides an overview of lubricants presented by Md. Arman Hossain of SAJ Engineering & Trading Company. It defines lubricants as substances that reduce friction between surfaces. The presentation covers the functions of lubricants, properties, classifications, types (mineral-based, synthetic, semi-synthetic), brands and institutes. It provides details on mineral oils, additives, and limitations while emphasizing advantages of synthetic lubricants. Pertamina lubricants and their approvals from automobile and equipment manufacturers are highlighted. The presentation stresses the importance of using quality lubricants for engine protection and performance.
This document discusses lubricants, including their need, classification, characteristics, types of lubrication, and applications. It defines lubricants as substances that reduce friction between surfaces in contact. Lubricants are classified as liquid, semi-solid, or solid based on their physical state. They function to reduce friction and wear, act as coolants, provide corrosion protection, and improve machine efficiency. Common types of lubrication include thick film lubrication which uses fluids to separate surfaces, and thin film or boundary lubrication which is used under heavy loads with high viscosity lubricants. Lubricants have wide applications in engines, transmissions, hydraulics, and other mechanical systems.
One of the most important things an operator can do for his machinery is to make sure it is properly lubricated. So what is a lubricant and how does it affect operations when used properly? In this webinar we will answer these questions and more by covering the fundamentals of lubrication. During this webinar we will discuss how a lubricant works to remove friction, the physical and chemical properties of the lubricant, and the many functions of a lubricant.
The document discusses lubrication systems for internal combustion engines. It describes the purpose of lubrication as reducing friction, protecting against wear, cooling, and removing impurities. It then explains different lubrication systems used in engines like mist, wet sump, and dry sump systems. It also discusses properties of lubricating oils like viscosity and viscosity index that impact engine performance. The document outlines various types of lubricants including animal, vegetable, mineral, and synthetic oils.
Grease is a thickened lubricant that remains in contact with moving surfaces. It is formulated from a base oil thickened with a soap, clay, or polymer. Grease properties depend on the base oil viscosity and consistency grade determined by penetration testing. Additives provide oxidation resistance, extreme pressure properties, anti-wear performance, and other characteristics. Standard tests evaluate grease properties like dropping point, oil separation, load carrying capacity, and resistance to water and corrosion. Proper grease selection depends on application parameters like temperature, speed, and load.
This document discusses lubricants used in chemistry. It covers the functions of lubricants in decreasing friction and absorbing heat. It describes different types of lubricants including oils, greases, and solid lubricants. It outlines the process for extracting lube oils from raw oil through steps like vacuum distillation, de-waxing, and hydrogen treatment. Key tests for lube oils are described like viscosity measurements and oxidation resistance tests. Factors for choosing lubricants are discussed like viscosity changes with temperature and resisting chemical reactions.
The document discusses different types of engine cycles including ideal, fuel-air, and actual cycles. It provides details on:
- Air standard cycles which are idealized and assume a perfect gas, no mass change, reversible processes, and constant specific heats. Examples include Otto, Diesel, and Dual cycles.
- Fuel-air cycles which are more accurate by considering the actual cylinder gas composition, variable specific heats, incomplete fuel-air mixing at high temps, and dissociation effects.
- Actual engine cycles use even more accurate models of the processes and working fluid, taking into account variable properties and chemical reactions.
This document discusses the design of journal bearings. It begins by introducing journal bearings and how they operate by allowing sliding along a circular surface to handle radial loads. It then describes the different types of journal bearings according to their angle of contact and lubricating layer thickness. The document outlines the materials commonly used for journal bearings and defines important terms in hydrodynamic journal bearings. It presents two main design methods - the M.D. Hersey method and the A.A. Raimondi and J. Boyd method - and provides overviews of the steps and considerations involved in each.
The ISPS Code is a comprehensive set of measures developed by the IMO to enhance maritime security. It was developed in response to terrorist attacks like 9/11 and the attack on the Limburg tanker. The ISPS Code has two parts - Part A which contains mandatory requirements for ships and port facilities, and Part B which contains guidance. Key elements of the ISPS Code include conducting vessel and facility security assessments to identify vulnerabilities, developing security plans, appointing security officers, controlling access to restricted areas, conducting drills and exercises, and setting security levels. Contracting governments are responsible for oversight of the ISPS Code and can authorize Recognized Security Organizations to assist with certain activities.
MARPOL Annex VI aims to reduce air pollution from ships. It regulates emissions of sulfur oxides, nitrogen oxides, particulate matter, and ozone depleting substances. The regulations establish emission control areas with more stringent standards for emissions of sulfur oxides and particulate matter. Ships must use low-sulfur fuel in these areas and meet emission limits for nitrogen oxides that become increasingly strict over time. Compliance is demonstrated through certification and testing of engines and fuels.
This document provides an overview of IMO regulations for improving ship energy efficiency, including:
- Chapter 4 of MARPOL Annex VI establishes mandatory energy efficiency standards for ships through the Energy Efficiency Design Index (EEDI) for new ships and the Ship Energy Efficiency Management Plan (SEEMP) for all ships.
- IMO resolutions provide guidelines for calculating the EEDI and developing SEEMPs.
- Ships must undergo surveys and be issued an International Energy Efficiency Certificate verifying compliance with Chapter 4 requirements.
This document lists the career history of Mohd. Hanif Dewan as a ship engineer from 1998 to 2013. It details the names of the ships he sailed on, their type and tonnage, the company that owned each ship, and his role on each ship, ranging from engine cadet to chief engineer. It worked on container ships, chemical tankers, product tankers, crude oil tankers and other tankers while employed by companies in Bangladesh, Singapore, the UAE, Iran, Japan, Malaysia and Saudi Arabia. The document concludes with Dewan's current role as a maritime lecturer and consultant in Malaysia.
This document discusses various methods for testing metals, including non-destructive testing methods like dye penetrant, magnetic crack detection, X-ray, and ultrasonic testing. It also describes tensile testing, which involves applying loads to a test piece to determine its elastic limit, yield point, ultimate tensile strength, and breaking point. Other tests discussed include proof testing, creep testing, hardness testing, and brittle fracture testing to evaluate metals at different temperatures.
Positive displacement pumps move fluids by trapping a fixed volume and forcing that volume from the suction to discharge side. Reciprocating pumps, like piston pumps, use reciprocating motion powered by engines while rotary pumps use rotating components like gears or lobes. Piston pumps have two check valves and a reciprocating piston powered by translating rotary motion into linear motion. They can be direct or indirect acting, simplex or duplex, and single or double acting. Diaphragm pumps use a flexible diaphragm instead of pistons. Rotary pumps have gears, lobes, screws, cams, or vanes that rotate to trap and move fluid and include gear, lobe, screw, vane, and cam pumps
The document discusses emissions to air from ships and strategies for reducing air pollution beyond regulatory compliance. It outlines various air pollutants emitted from ships, such as nitrogen oxides (NOx) and sulfur oxides (SOx), and regulations from the International Maritime Organization (IMO) to limit these emissions. Methods for reducing ship emissions are discussed, including using low-sulfur fuel, exhaust gas cleaning systems, and operational measures like slow steaming. The document emphasizes that reducing emissions requires approaches throughout the combustion process, from fuel preparation to exhaust cleaning.
The document lists Mohammud Hanif Dewan's activities giving technical seminars and talks on MARPOL Annex VI and ship energy efficiency management. It provides details of six separate seminars or talks he gave between July 2015 and May 2016 in Dhaka, Bangladesh and Kuala Lumpur, Malaysia. The seminars and talks were arranged by various marine organizations and covered topics around air pollution regulations, greenhouse gas emissions, and energy efficiency regulations for ships.
The cylinder liner forms the cylindrical space in the engine where the piston reciprocates. It is manufactured separately from the cylinder block using an alloy that has better wear resistance at high temperatures. This allows for replacement of just the liner if it wears. The liner is cooled, often with tangential bore cooling, to maintain an optimal temperature for lubrication and reducing thermal stresses. Proper lubrication and minimizing abrasive particles are important to reduce liner wear over the life of the engine.
The SOLAS 74 convention is the key international maritime treaty that sets baseline safety standards for the construction, equipment and operation of ships. It has been updated numerous times since first adopted in 1974. The convention includes 12 chapters that address topics like ship construction, lifesaving appliances, radiocommunications, safety of navigation, dangerous cargo carriage, and management for safe ship operation. It requires ships to be surveyed and certificated to verify compliance with SOLAS standards. Major codes made mandatory under SOLAS include the ISM code for ship management and specialty codes for chemical tankers and gas carriers.
Steel is the most widely used material in shipbuilding, comprising about 90% of materials. The key properties materials must have include strength, weldability, toughness, resistance to marine corrosion, formability, and cost effectiveness. Various grades of steel are used - Grade A for thinner structures, Grade B for medium thickness, and Grades D and E for thicker, high-stress areas. Materials used in sea water systems include 90/10 cupro-nickel, which is resistant to corrosion and clogging, and stainless steel, which requires regular cleaning to prevent pitting. Expected lifespans are 6-9 years for galvanized steel and over 10 years for cupro-nickel alloys.
This document discusses gear pumps, including their operation, types, maintenance, and uses. It begins by defining pumps as devices that add energy to fluids to move them from one point to another. It then explains that gear pumps are a type of rotary, positive displacement pump that uses meshing gears to pump liquids. The document describes how gear pumps work by trapping liquid between gear teeth and casing as the gears rotate. It also discusses gear pump components, maintenance like checking clearances and changing seals, the use of relief valves for safety, and applications like pumping fuels and lubricants.
This document discusses classification societies and their role in classifying ships. Classification societies set technical and safety standards for ships and ensure they are properly maintained through regular surveys. They assign ships a class rating which is valid for typically 5 years and indicates the risk level for insurers. Major classification societies around the world include Lloyd's Register, American Bureau of Shipping, Bureau Veritas, Det Norske Veritas, and others.
Castrol held a 3-module marketing training event for 200 delegates over 9 months. Module 3 was a 3-day conference at the ExCel center in London, featuring presentations, workshops, and networking activities. It concluded with a gala dinner cruise on the Thames and finale presentations. Venues Event Management planned the logistics, registration, and produced marketing materials to tie the events together for the delegates.
Acorn Automotive Lubricants_Marketing Communications Plan Dele Ogundahunsi
Abridged copy of Marketing Communications plan for Acorn automotive lubes. To get your downloadable full version (48 slides), go to http://flevy.com/browse/business-document/acorn-automotive-lubricants-marketing-communications-plan-1403
Total Telecom Roadshow Presentation 2014Rob Chambers
Updated Total Telecom portfolio information, including:
- Asia Communication Awards
- Network Management Show
- IPX Summit
- Carriers World
- World Communication Awards
- Future security Summit
As well as briefings, publishing and more.
The document discusses lubricants and lubrication mechanisms. There are three main types of lubrication mechanisms: 1) hydrodynamic or thick film lubrication, where a thick layer of lubricant separates moving parts; 2) boundary or thin film lubrication, where a thin film of lubricant is adsorbed onto metal surfaces to prevent direct contact; and 3) extreme pressure lubrication, where additives are used to form surface layers able to withstand high temperatures and pressures. Lubricants are used to reduce friction between machine parts and increase efficiency. The type of lubrication used depends on factors like speed, load, and viscosity.
This document discusses properties of lubricants and lubrication. It defines lubricants as substances used to decrease friction between moving machine parts, and lubrication as the process of doing so. It describes the composition of lubricating oils and various properties that affect lubricant performance such as viscosity, viscosity index, iodine number, aniline point, flash point, and pour point. The document also discusses the functions of lubricants in minimizing heat production, wear, and energy loss. It notes various additives used to protect and improve lubricants, such as oxidation inhibitors, corrosion inhibitors, and detergents.
Properties of Lubricats and Lubrication-Edit.pptxHome
One important reason why lubrication is used in various types of machinery is that it reduces friction and when Friction is reduced, the lifespan of our machinery will increase, and wear will also reduce. Given the above, this presentation, explains the properties of Lube Oil in depth. It also explains how Lube oil can be taken and stored on board a ship. The various checklists to fill in before and after taking the lube oil. Emphasis is also made on the importance and functions of lube oil and do they apply to the overall efficiency of the various machinery onboard.
The document describes the production of bio-grease from scrap aluminum. It discusses that bio-grease is more environmentally friendly than traditional grease and provides various desirable properties. Aluminum-based bio-grease is a good example as its raw materials of aluminum scrap, stearic acid, and vegetable oil are all natural products. The document then outlines the experimental method for producing bio-grease which involves pretreating aluminum scrap through chemical cleaning before reacting it with sulfuric acid to produce aluminum sulfate, a thickening agent.
This document discusses lubrication technology and provides information on greases and lubricating oils. It outlines the duties of lubrication personnel, including using the correct lubricants, applying them properly, keeping records, and minimizing costs. The document also describes properties of greases like consistency, dropping point, and thickener types. Common tests for grease properties are outlined. Finally, key properties and tests for lubricating oils are summarized, including viscosity, viscosity index, wear tests, and flash/pour points.
This document defines lubricants and lubrication and describes the characteristics of good lubricants. It discusses the main mechanisms of lubrication including thick film lubrication using liquid lubricants, thin film boundary lubrication using semi-solid and solid lubricants, and extreme pressure lubrication using additives. The document also classifies lubricants as liquid, semi-solid greases, and solid lubricants like graphite and molybdenum disulfide. Finally, it outlines important properties of lubricants such as viscosity, viscosity index, flash point, pour point, and carbon residue.
1. Lubrication is the process of applying a lubricant between two surfaces to reduce friction. Early humans discovered lubrication reduced effort and wear in simple machines.
2. The document defines lubrication and lubricants, and discusses the primary purposes of lubrication as reducing friction, wear, and excessive heating. It also lists several secondary purposes like extended equipment life and reduced costs.
3. The properties of viscosity, flash point, and viscosity index are among the most important properties of lubricating oils discussed in the document. Various lubricant classifications like ISO, SAE, and AGMA viscosity grades are also covered.
This document provides an overview of lubricating oils and the lubricant blending process. It defines lubricants and lubrication mechanisms. It describes the types of base oils (mineral and synthetic) and additives used in lubricants. The key equipment in a lube oil blending plant and the blending process are outlined, including base oil and additive charging, blending, and quality control testing. Key tests described are kinematic viscosity, viscosity index, pour point, and flash/fire point determination. In summary, the document introduces lubricating oils, their composition and properties, and the blending process used to produce finished lubricant products.
Lubricants such as oils, greases, and other substances are used to reduce friction between moving parts and prevent wear. There are various types of lubricants including mineral, synthetic, vegetable, and animal-based. Oils are used for lubrication through boundary, hydrodynamic, and elastohydrodynamic methods. Greases are also used for lubrication and provide advantages over oils by remaining in contact with moving surfaces longer. Synthetic lubricants were developed to withstand higher operating temperatures than petroleum-based lubricants. Proper lubricant selection and maintenance is important for optimal machinery performance and longevity.
Frictional heat is generated when metallic parts contact each other during relative motion. This causes power loss. Lubricants can minimize friction by maintaining a thin film between surfaces. Good lubricants have appropriate viscosity, high flash/fire points, oiliness to adhere to surfaces, and low volatility and carbon residue. Common lubrication systems like splash lubrication in engines work by splashing oil from a sump onto moving parts like pistons.
Lubrication is one of the main preventative maintenance activities.
Lubricants have a wide range of properties that impact their physical and chemical properties Knowing about these properties is important in determining which lubricant is best for which situation.
Oil analysis identifies early signs of contamination, fluid degradation and abnormal wear before they cause costly and permanent damage to equipment.
If we want to understand the principles of Lubrication, it becomes extremely important to learn about Viscosity because Viscosity is perhaps the single-most important factor and characteristic of oil which directly impacts the performance of the engine. Let’s go back to the definition to get a clear understanding!
https://shieldoils.com/principles-of-lubrication/
This presentation contains detailed classification of Lubricants on the basis of raw material, usages and viscosity( Monograde oils and Multigrade oils). This presentation will be more helpful to students and researchers by understanding lubricants in details.
The FUCHS Lubricants book _regarding greases.pdfssuser5599ce
The document provides information about greases, including their composition, properties, and appropriate testing methods. It discusses that greases consist of a base oil, thickener, and additives. The thickener determines properties like mechanical stability and water resistance. Various types of thickeners and base oils are described. Additives can improve properties like oxidation resistance and corrosion protection. Testing methods for grease include measuring viscosity, dropping point, copper corrosion resistance, water resistance, load bearing capacity, and wear resistance. Choosing the right grease depends on factors like temperature, load, and operating speed.
The document discusses energy efficiency measures in the shipping industry and barriers to their adoption. It identifies key stakeholders in ship operation and their influence on implementing energy efficiency. A literature review found the most common barriers include lack of information, financial constraints, technical risks, and lack of crew awareness/training. A pilot survey was conducted to validate questionnaires on barriers. The main survey collected data from 91 stakeholders in Bangladesh and Malaysia on their influence level on 18 energy efficiency measures. The findings show measures with very high influence levels include improved voyage planning, speed optimization, hull cleaning, and propeller cleaning.
This document discusses ship rudders, including:
- Rudders are fitted at the aft end of ships to provide directional control and derive benefit from increased water velocity from the propeller.
- There are three main types of rudders - balanced, unbalanced, and semi-balanced. Balanced rudders have a portion of blade area forward of the stock to reduce torque on the steering gear.
- Size, shape, and type of rudder is governed by the ship's stern shape, required rudder area, steering gear capacity, and service conditions.
- Special rudders like spade rudders, Flettner/Becker rudders, Borg
Static forces on a ship include internal forces from structural weight and cargo and external static forces from hydrostatic pressure. Dynamic forces result from ship motion at sea, wind and waves, and operating machinery. A ship has six degrees of freedom of motion: rolling, surging, pitching, swaying, heaving, and yawing. Ship motion introduces dynamic forces that cause stresses on the ship's structure. Methods to reduce rolling include bilge keels, passive tanks, controlled passive tanks, active tanks, and fin stabilizers.
The document summarizes the key structural components of a ship's hull, including longitudinal members like the keel, longitudinals, deck girders and stringers, as well as transverse members like floors, frames, and deck beams. It describes the primary roles of longitudinal and transverse members in resisting stresses. It also discusses different framing systems including transverse, longitudinal and combination systems, and notes their advantages and disadvantages for different ship types and sizes.
This document provides definitions and explanations of key concepts related to a ship's transverse stability. It discusses heel and list, stability reference points like the metacenter, center of buoyancy, and center of gravity. It introduces the stability triangle and explains positive, neutral, and negative stability. Key terms are defined, such as displacement, draft, and the laws of buoyancy. Graphs demonstrate concepts like the righting arm curve and how stability changes with angle of heel. The roles of factors like GM, GZ, and the angle of loll in capsizing are also summarized.
The document summarizes activities and facilities at the Liberia Maritime Training Institute. It describes the administration building, academic block, and cadets' block. It also mentions a new technical workshop for hands-on training in marine engineering, welding, machining, and electronics. Photos show cadets participating in parade training, classroom lectures, and practical training in the workshop and labs to bridge theoretical knowledge with practical skills. Facilities include a firefighting training center, computer lab, science labs, and areas for physical training, swimming, games, and hiking.
This document provides information about the Liberia Maritime Training Institute (LMTI) and its Liberia Maritime Preparatory Academy (LMPA) program. LMPA is a 2-year diploma program that offers specialized training in electrical and electronics engineering or marine engineering through theoretical coursework and hands-on practical training. The goal is to qualify young Liberians for careers as marine engineers, electro-technical officers, or other industrial jobs. The program is structured into four semesters with practical training in workshops, laboratories, and operating industrial machinery and ship systems. Upon completing the program, graduates will be prepared for careers supporting the maritime and industrial development of Liberia.
This document discusses traditional Malaysian clothing and cultural items. It describes the batik shirt, songkok cap, baju melayu outfit worn by Malay men, kain pelikat fabric wrap, baju kurung dress worn by women, wau moon kites, bunga telur decorated eggs, and mengkuang mats woven from leaves. These items are an important part of Malaysian culture and worn for occasions like weddings or as uniforms.
This document provides information about Congkak, a traditional mancala game originating from Malay culture. It discusses that Congkak is believed to come from old Malay and involves mental calculation strategies. The game is played with cowrie shells or seeds in carved wooden boards of 7 or more holes on each side. It then explains the basic rules where players take turns sowing seeds between holes to capture their opponent's seeds, with the goal of ending with more seeds in their storage hole. Congkak was likely introduced to Southeast Asia in the 15th century and spread throughout the region, becoming a popular pastime especially for families and women.
This document provides information about satay, a Southeast Asian dish of seasoned, skewered and grilled meat. It originated in Java, Indonesia and is now popular in many Southeast Asian countries and former Dutch colonies. In Malaysia, satay is the national dish and has a sweeter sauce than versions from other countries. The document discusses the ingredients, preparation methods and history of satay, and includes photos of different types of satay dishes from various regions.
This document discusses ship energy efficiency and regulations to reduce greenhouse gas emissions from ships. It provides background on increasing carbon dioxide levels and the need to reduce emissions from the shipping industry. The document summarizes International Maritime Organization regulations including the Energy Efficiency Design Index, which sets mandatory energy efficiency standards for new ships, and the Ship Energy Efficiency Management Plan, which provides a mechanism for ships to improve their energy efficiency. It describes methods to calculate the EEDI and requirements for attaining the EEDI. Finally, it discusses technologies and operational measures that can help ships improve their energy efficiency and comply with regulations.
The document discusses various renewable and non-renewable energy sources that can be used to power ships, including their advantages and disadvantages. It examines fossil fuels currently used like diesel, as well as alternative fuels like liquefied natural gas (LNG), biofuels, hydrogen, and renewable options such as wind, solar and nuclear energy. While renewable sources avoid pollution, they have limitations related to availability and technology. The best approach may be to use alternative fuels and renewable sources together to supplement fossil fuels and reduce environmental impacts from shipping.
Heat treatment involves heating and cooling metals to alter their internal structure and properties. There are several heat treatment methods for carbon steels including annealing, normalizing, hardening, and tempering. Annealing involves heating steel to high temperatures and slowly cooling to relieve stresses and improve ductility. Normalizing also starts with heating above the critical point but involves air cooling to refine grain size. Hardening greatly increases hardness but causes brittleness, so tempering is used to relieve stresses and improve toughness through controlled reheating.
Corrosion is the deterioration of metals through chemical reactions with the environment. There are several types of corrosion, including galvanic corrosion which occurs when two dissimilar metals are in electrical contact in an electrolyte, leading the less noble metal to corrode faster. Pitting corrosion causes localized holes or pits in the metal surface. Selective leaching corrosion removes specific elements from alloys, like removing zinc from brass. Proper material selection, coatings, inhibitors, and cathodic protection can prevent various corrosion types.
1. The document provides information on ship construction, including definitions of key ship design terminology and descriptions of basic ship types and designs.
2. It discusses the three main stages of initial ship design - concept, preliminary, and contract design. Key ship dimensions and specifications that are determined at each stage are outlined.
3. Ship types covered include liquid cargo ships, dry cargo ships, passenger ships, offshore vessels, fishing vessels, and naval vessels. The evolution of cargo ship designs over time is summarized.
- Energy efficiency technologies can significantly reduce energy usage and costs for ships through innovations like hull design improvements, efficient propulsion systems, waste heat recovery, and alternative fuels.
- Examples of promising technologies include air lubrication systems to reduce hull resistance, optimized propeller and rudder designs, waste heat recovery systems, and use of sails or kites to capture wind power.
- Adopting a portfolio of these technologies through concepts like the low loss power distribution system, combined diesel-electric propulsion, or efficient auxiliary systems can lower energy usage on ships by 5-30% depending on the vessel type and operational profile.
This document defines and explains several key terms and measures related to ship energy efficiency and emissions:
- The EEDI is an index that quantifies a ship's carbon dioxide emissions based on the goods transported, and new ships must meet required EEDI limits.
- The IEEC is a new certificate issued to ships over 400 gross tonnage to document their attained EEDI and SEEMP.
- The SEEMP is a ship's energy efficiency management plan to improve operations and link to corporate policy.
- The EEOI is an efficiency indicator calculated based on a ship's fuel consumption, voyage distance, and cargo that allows comparison of emissions between ships.
The document discusses various energy efficiency measures for ships and potential barriers to their adoption. It provides definitions for key terms related to energy efficiency like the Energy Efficiency Design Index (EEDI), Ship Energy Efficiency Management Plan (SEEMP), and Energy Efficiency Operational Indicator (EEOI). Technical measures to improve efficiency include hull design optimization, waste heat recovery, speed reduction, and the use of alternative fuels. However, barriers remain like split incentives between ship owners and operators and a lack of knowledge sharing across technical systems.
How to Manage Access Rights & User Types in Odoo 17Celine George
In Odoo, who have access to the database they are called users. There are different types of users in odoo and they have different accesses into the database. Access rights are permissions that can be set for the individual or group of users. This slide will show How to Manage Access Rights & User Types in Odoo 17.
Codeavour 5.0 International Impact Report - The Biggest International AI, Cod...Codeavour International
Unlocking potential across borders! 🌍✨ Discover the transformative journey of Codeavour 5.0 International, where young innovators from over 60 countries converged to pioneer solutions in AI, Coding, Robotics, and AR-VR. Through hands-on learning and mentorship, 57 teams emerged victorious, showcasing projects aligned with UN SDGs. 🚀
Codeavour 5.0 International empowered students from 800 schools worldwide to tackle pressing global challenges, from bustling cities to remote villages. With participation exceeding 5,000 students, this year's competition fostered creativity and critical thinking among the next generation of changemakers. Projects ranged from AI-driven healthcare innovations to sustainable agriculture solutions, each addressing local and global issues with technological prowess.
The journey began with a collective vision to harness technology for social good, as students collaborated across continents, guided by mentors and educators dedicated to nurturing their potential. Witnessing the impact firsthand, teams hailing from diverse backgrounds united to code for a better future, demonstrating the power of innovation in driving positive change.
As Codeavour continues to expand its global footprint, it not only celebrates technological innovation but also cultivates a spirit of collaboration and compassion. These young minds are not just coding; they are reshaping our world with creativity and resilience, laying the groundwork for a sustainable and inclusive future. Together, they inspire us to believe in the limitless possibilities of innovation and the profound impact of young voices united by a common goal.
Read the full impact report to learn more about the Codeavour 5.0 International.
How to Create & Publish a Blog in Odoo 17 WebsiteCeline George
A blog is a platform for sharing articles and information. In Odoo 17, we can effortlessly create and publish our own blogs using the blog menu. This presentation provides a comprehensive guide to creating and publishing a blog on your Odoo 17 website.
This is an introduction to Google Productivity Tools for office and personal use in a Your Skill Boost Masterclass by the Excellence Foundation for South Sudan on Saturday 13 and Sunday 14 July 2024. The PDF talks about various Google services like Google search, Google maps, Android OS, YouTube, and desktop applications.
Mail Server Configuration Using App passwords in Odoo 17Celine George
In Odoo 17, we can securely configure an email server to send and receive emails within the application. This is useful for features like sending quotations, invoices, and notifications via email. If our email service provider (e.g., Gmail, Outlook) supports app passwords, we can use them to authenticate our Odoo instance with the email server.
Odoo 17 Events - Attendees List ScanningCeline George
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Properties of Lubricats and Lubrication
1. i f b iProperties of Lubricants
and
Lubrication
Mohd Hanif Dewan Senior Engg Lecturer Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
3/14/2014 1
2. Lubricant:Lubricant:
The substances which are used to decrease the force of friction
between the moving parts of machine in contact are known as
Lubricants and the process of decreasing the force of friction
between the moving parts of machine in contact is known as
LubricationLubrication.
Composition of lubricating oils:
Lubricating oil fractions extracted from crude oil are a widely
varying mixture of straight and branched chain paraffinic,
napthenic aromatic hydrocarbons having boiling points rangingnapthenic aromatic hydrocarbons having boiling points ranging
from about 302o to 593oC. Some specialty lubricants may have
boiling point extremes of 177 and 815oC. The choice of grade ofg p g
lubricating oil base is determined by the expected use.
3/14/2014 2
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
3. FRICTION:
When on surface of machinery moves over the anothery
surface, resistance to relative motion of the surfaces
arises. When we look at the solid surface it appears
smooth to naked eye but this smooth surface showssmooth to naked eye , but this smooth surface shows
irregularities of projections and cavities when viewed
under high power microscope.
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh3/14/2014
4. Wh h f i l d th itWhen one such surface is placed over another, its
projections fall into the cavities of the other and get
interlocked Due to this interlocking there isinterlocked .Due to this interlocking , there is
resistance to the relative motion of the surfaces.
This is called the frictional forces or frictional
resistance of friction. In due course of motion, the
old projections get broken and deformities arise.
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh 43/14/2014
5. So, FRICTION may be defined as the opposing force
that is set up between the surface of contact, whenp
one body moves over the surface of another body.
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh 53/14/2014
6. EFFECT OF FRICTION:
The frictional forces oppose the relative motion between
the moving parts of a machine Therefore extra energythe moving parts of a machine. Therefore extra energy
has to be spent to overcome the friction , which
increases expenses of energy .The friction between
the moving parts of machines also produces heat
which causes damage to the machinery. Thus friction
causes wear and tear of the moving parts of machinerycauses wear and tear of the moving parts of machinery
in contact and due to this cause, the machines lose
their efficiency and become useless.
3/14/2014 6
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
7. FUNCTIONS OF LUBRICANTS:
I. Lubricants avoid the damage of the moving parts of machines
by minimizing the production of heat.
II Lubricants reduce the wear and tear of machinery by keepingII. Lubricants reduce the wear and tear of machinery by keeping
the moving parts of machines apart.
III. Lubricants reduce the maintenance and running cost of
machinemachine.
IV. Lubricants act as the coolant because it reduces the
production of heat between the moving parts of machine in
contactcontact.
V. Lubricants increases the efficiency of machine by reducing the
loss of energy.
VI B i th l b i t th l ti ti f th i tVI. By using the lubricants, the relative motion of the moving parts
of machine becomes smooth and noise level of running
machine reduces.
VII L b i t l t th i tVII. Lubricants also act as the corrosion preventers.
3/14/2014
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
8. VIII.Lubricants also act as a seal as in piston. Lubricant
used between piston and walls of the container (cylinder)
prevents the leakage of hot gases produced by theprevents the leakage of hot gases produced by the
internal combustion i.e.it act as seal.
3/14/2014 8
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
9. General capabilities expected from an engine lubricant:
Di i it it t th ld t f i l- Dispersivity or capacity to the cold parts of an engine clean
- Detergency or capacity to keep hot parts of an engine clean
- Thermal strength or capacity to withstand temperature changes
- Anti-oxidant or capacity to resist the action of oxygen
- Anti-wear or capacity to contain wear
- Anti-scuffing or capacity to preserve oil film even in the presence
of high pressures.
- Alkalinity reserve or capacity to neutralise acids formed during
combustion or other sources thereby preventing corrosive wear.
- Demulsibility or capacity to separate contaminants.
- Resistance to hydrolysis or capacity to withstand the action of
water which can affect additives Pumpabilityp y
- Centrifugibility and filterability or capacity to separate insoluble
elements.
- Anti-rust, anti-corrosive and anti-foam are just some of the other, j
properties which protect the metalic object from wear down.
3/14/2014 9
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
10. NORMAL PROPERTIES REQUIRED ARE:NORMAL PROPERTIES REQUIRED ARE:
1. Adequate viscosity at working temperature so that the oil
spreads over the liner surface to provide a tough film which resists
th ti f th i t ithe scrapper action of the piston rings.
2. The oil must provide an effective seal between the rings and
liner.
3. Only a soft deposit must be formed when the oil burns,
4.Alkalintiy level (total base number or TBN) must match the
acidity of the oil being burntacidity of the oil being burnt.
5. Detergent and dispersant properties are required in order to
hold deposits in suspension and thus keep surfaces clean.
3/14/2014 10
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
12. VISCOSITY:
• It’s a measure of a fluid’s resistance to flow.
• Viscosity of the lubricating oil determines its performance under
operating conditions.
• A low viscosity oil is thin and flows easily .
• A high viscosity oil is thick and flows slowly.
• As oil heats up it becomes moreAs oil heats up it becomes more
viscous (Becomes thin)
• Too low viscosity of the liquid > Lubricant film cannot be maintained
between the moving surfaces > Excessive wear.between the moving surfaces Excessive wear.
• Too high viscosity of the liquid > Excessive friction.
• Selected Lubricant must be proper viscous.
Viscosit is s all e pressed in centipoise or centistoke• Viscosity is usually expressed in centipoise or centistoke.
13. Viscosity Index :
• It is “Avg. decrease in viscosity of oil per degree rise in temp between
1000F & 2100F.”
• Viscosity of liquids decreases with increasing temperature.
• The rate at which viscosity of a lubricant changes with temperature is
measured by a scale called Viscosity Index.
• Silicones, polyglycol ethers, Diesters or triesters have high Viscosity Index.
Determination of Viscosity Index :
• First the viscosity of the oil under test is determined at 100°F & 210°F.
Let it be U and V respectively.y
• Then viscosity of Pennsylvanian oil is determined. Let it be VH.
• Then viscosity of Gulf oil is determined. Let it be VL
viscosity Index = VL- U x 100
L
Uy L
VL- VH
V.I. = 100 (Pennsylvanian oils.)
V.I. = Zero (Naphthanic-base gulf oils)
Viscosity
Temp
100O 200
H
F
( p g )
Higher the V.I, lesser is the variation of viscosity with change in
temperature.Thus, a good lubricating oil should possess high V.I.
Temp
14. • Iodine number is the number of Gms equivalent of iodine to amount of ICl
absorbed by 100gm of oil.
• Each oil has its specific Iodine Number.
• So Iodine Number determines the extent of contamination of oil.
• Low Iodine Number is desirable in oils.
Some oils and their Iodine Numbers are given below :
Iodine Number Oil Example
>150 Drying oil Linseed oil, tung oil
100‐150 Semidrying oil Castor oil , Soyabean oil100 150 Semidrying oil Castor oil , Soyabean oil
<100 Non‐Drying oil Coconut oil, Olive oil
15. • Aniline point is the Min temp at which oil is miscible with equal amt of
aniline
• Aniline Point is a measure of aromatic content of the lubricating oil• Aniline Point is a measure of aromatic content of the lubricating oil.
• Low Aniline Point oil have high aromatic content which attacks rubber
seals.
• Higher Aniline point means low %age of hydrocarbons (desirable).
• Thus Aniline Point is used as an indication of possible deterioration of • Thus Aniline Point is used as an indication of possible deterioration of
rubber sealing etc.
Determination of Aniline Point :
A ili Homogeneous Aniline +
sample oil
(equal)
Heated in Test tube
Homogeneous
solution
Coooled
Cloudiness
The temperature at which separation of the two phases (Aniline + oil) takes place
is the Aniline Point.
16. • Emulsification is the property of water to get mixed with water
easilyeasily.
• Emulsions can be oil in water emulsion or water in oil emulsion.
• A good lubricating oil should form such an emulsion with water
which breaks easily. This property is called demulsification.which breaks easily. This property is called demulsification.
• The time in seconds in which a given volume of oil and water
separates out in distinct layers is called steam demulsification
number.
• A good lubricating oil should have lower demulsification
number.
• Quicker the oil separates out from the emulsion formed, better
i th l b i ti ilis the lubricating oil.
• In cutting oils the higher the emulsification number, better the
oil is. This is because the emulsion acts as a coolant as well as
a lubricanta lubricant.
17. • Flash Point is the min temp at which the lubricant vaporizes that ignite for
a momwhen tiny flame is brought near.
• Fire Point is the Min temp at which the lubricant’s vapours burn constantly• Fire Point is the Min temp at which the lubricant s vapours burn constantly
for 5 seconds when tiny flame is brought near.
• Fire point = flashpoint+5 to 400C.
• Both should be higher than the max temp of country (for transportation)Both should be higher than the max temp of country (for transportation)
• If flash point < 140°F = Flammable liquids
And if flash point > 140°F =Combustible liquids.
The flash and fire points are generally determined by
using Pensky-Marten’s apparatus.
•Oil under examination is filled in the oil cup up to the
k d h t d b th i b th b bmark and heated by the air bath by a burner.
•Stirrer is worked b/n tests at a rate of about 1 – 2
rev/sec.
•Heat is applied so as to raise the oil temp by about
5c/min.5c/min.
•The temp at which distinct flash appeared in side the
oil cup is recorded as flashpoint.
•The heating is continued to record the fire point.
18. • Drop Point is the Temperature
at which grease passes fromg p
the semi-solid to the liquid
state. So, it determines the
upper temp limit for theupper temp limit for the
applicability of grease.
Determination :Determination :
• Beaker is heated.
• Temperature is raised.
• Grease sample passes from aGrease sample passes from a
semi-solid to a fluid state.
• Temp at which its first drop
falls from the opening isfalls from the opening is
recorded as drop-point.
19. • Cloud Point is the temp at which the lubricant becomes cloudy
or hazy when cooled.
• Pour Point is the temp at which the lubricant just ceases to flow
when cooled.
• Both indicates suitability of lubricant in cold conditions and thusot d cates su tab ty o ub ca t co d co d t o s a d t us
must be low.
• Pour point of wax can be lowered by dewaxing or adding
suitable pour point depressantsuitable pour point depressant.
• Pour point of an oil can be lowered by lowering the viscosity of
the oil which is achieved by removing the viscous constituent of
th ilthe oil.
• Lubricating oils used in capillary feed systems should have low
cloud points, otherwise impurities will clog the capillary.g y
• A high pour point leads to the solidification of the lubricant that
may cause jamming of the machine.
20. • Neutralization Point determines Acidity or Alkalinity of oil.
A idit /A id l /A id b i f KOH i d t• Acidity/Acid value/Acid number is mgs of KOH required to
neutralize acid in 1 gm of oil.
• Alkalinity/Base value/Base number is mgs of acid required
to neutralize all bases in 1 gm oil.
• As Neutralization Point of oil increases, age of oil
decreasesdecreases.
21. • It’s the mgs of KOH required to saponify 1 gm of oil.
S ifi ti i h d l i f E t ith KOH t i• Saponification is hydrolysis of an Easter with KOH to give
alcohol and Na/K salt of acid.
• Mineral oils do not react with KOH and are not saponifiable.
• Vegetable and animal oils have very high saponification
values.
Significance
• Saponification value helps us to ascertain whether the oil
d f i i l t bl ilunder reference is mineral or vegetable oil or a
compounded oil.
• Each oil has its specific Soaponification Number.
Deviation from it indicates the extent of adulteration of oil.
22. ADDITIVESADDITIVES
Improvements in lubricating oil over the last twenty
years have come about almost entirely from the useyears have come about almost entirely from the use
of additives.
These are added for three main reasons;
1.to protect the lubricant in service by limiting the
h i l h d d t i tichemical change and deterioration
2.To protect the mechanism from harmful
combustion products and malfunctioningcombustion products and malfunctioning
lubricating oil
3.To improve existing physical properties and top g p y p p
create new beneficial characteristics in the oil
3/14/2014 22
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
23. Typical additives are:yp
Barium, calcium, phosphorus, Sulphur, chlorine, zinc, oxidation
inhibitor-increases oil and machinery life, decreases sludge and
varnish on metal parts.varnish on metal parts.
Corrosion inhibitor- protects against chemical attack of alloy
bearings and metal surfacesbearings and metal surfaces.
Antiwear improvers- protects rubbing surfaces operating with this
film boundary lubrication. One such antiwear ( and oxidation
inhibitor) chemical is Zinc dithiophosphate or ZDDPinhibitor) chemical is Zinc dithiophosphate or ZDDP
Detergent- tend to neutralise the deposits before formation under
high temperature and pressure conditions, or as a result of using a
fuel with high sulphur contentfuel with high sulphur content.
Dispersant- used to disperse or suspend the deposits forming
contaminants. Typical dispersants, such as polyesters and
benzlamides are usually clean burning The molecules have abenzlamides, are usually clean burning. The molecules have a
polar charge at one end which attracts and holds the deposits
3/14/2014 23
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
24. Alkaline agents- neutralises acids, htese form the TBN of the oil
and includes additives such as the above dispersants and
detergents. An excess of acid neutralising alkalis are present in thedetergents. An excess of acid neutralising alkalis are present in the
oil and these help to keep parts clean. Failure to keep an oil
alkaline can lead to damage to bearings due to acidic attack as
well as increased liner wearwell as increased liner wear.
Rust inhibitors- protect to form the oxidation of metal component.
Pour point depressants- improves low temperature viscosity
Oiliness agent- reduces friction seizure point and wear ratesOiliness agent- reduces friction seizure point and wear rates
EP additives- increases film strength and load carrying capability
Antifoam agents- prevents stable bubble formation
Viscosity Improvers an additive that improves the viscosity indexViscosity Improvers- an additive that improves the viscosity index
of the oil. I.e. reduces the effect of temerpature of the oil.
Metal deactivators- prevent catalytic effects of metal
Antiseptic bactericideAntiseptic- bactericide.
3/14/2014 24
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
26. LUB OIL ANALYSIS:
Regular testing of crankcase lub oil is important to ensure that
deterioration has not taken place. The results of in service deterioration
could be a reduction in engine protection or actual attack on working
points by corrosive deposits. Oil samples are generally tested every 3 top y p p g y y
4 months depending on the system and experience. Shipboard testing is
taking a rising prominence to allow monitoring of oil condition between
testing.
To ensure good representation care should be taken where the sampleTo ensure good representation, care should be taken where the sample
is drawn
Correct
Main supply line
inlet or outlet from lub oil cooler
Outlet from main lub oil pump
Incorrect
standpipesstandpipes
purifier outlet
purifier direct sump suction
Samples should be drawn over a period of several minutes
3/14/2014 26
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
27. ViscosityViscosity
The viscosity is the most important property of the oil. Oil
of correct viscosity will provide optimum film strength withof correct viscosity will provide optimum film strength with
minimum friction losses and leakage.
The viscosity of a L.O. may fall due to fuel dilution if
running on gas oil, and rise if running on heavy f.o.
Viscosity may also increase due to heavy soot loading if
purifiers and filters not operating efficiently. Oil ageing
caused by oxidation and thermal degradation increases
viscosity.
A simple shipboard test is the Mobil flow stick wherep p
drops of new and used oil are placed in separate
channels on an inclined 'stick'. The rate the oil flows
down the stick is proportional to its viscosity.p p y
3/14/2014 27
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
28. Water contentWater content
Initially determined by 'crackle' test. The
presence of Na and Mg in a 4:1 ratio indicatespresence of Na and Mg in a 4:1 ratio indicates
salt water contamination.
Limits are laid down by the manufacturer but asLimits are laid down by the manufacturer, but as
a rule of thumb a limit of 0.2% should cause
investigation into source and remedial action at
0.5%
Gross contamination can be remedied by placing
the charge in a separate tank and heating to
70oC and circulating through purifier.
3/14/2014 28
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
29. SpectrometrySpectrometry
Indicates the presence of metal element composition and
identifies additive and contaminant levels.
Zinc(Zn),Phosphorus(P)- are components of many oils
such as diesel engine oils, hydraulic oils and gear oils, to
enhance antiwear and over properties of the oilp p
Calcium(Ca)- primarily a component of engine oils,
provides detergency,alkalinity and resistance to
oxidation. Residual fuel engine oils have higher Ca levels
Nickel(Ni)- Bearings, Valves, gear plating, fuel derivative
Barium(Ba)- Multi purpose additive, declining importance
Magnessium(Mg)- as for Ca may also be due to seaMagnessium(Mg) as for Ca, may also be due to sea
water contamination if found in Ratio of 1:4 of Na
Chromium(Cr)- Piston rings, hydraulic actuator cylinders
Manganese(Mn)- Cylinder wearManganese(Mn)- Cylinder wear
3/14/2014 29
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
30. Aluminium(Al)- generally comes from wearing piston skirts,( ) g y g p
levels rise where new piston fitted to old engine. Typically
10ppm, but rises during bedding in. May also indicate the
presence of catylytic fines in residual fuels.
Iron(Fe) Molybdenum(Mo) Chromium(Cr) metals alloyedIron(Fe), Molybdenum(Mo), Chromium(Cr)- metals alloyed
for piston ring etc, a rise in level may indicate ring pack/liner
wear.
Copper(Cu), Lead(Pb) , Tin(Sn), Silver(Ag) - soft metalsCopper(Cu), Lead(Pb) , Tin(Sn), Silver(Ag) soft metals
used in the overlay of shell bearings, and phosphor bronze
gears.Note that high copper content can also occur when
samples are drawn from copper pipes which have not been
flushed as well as gear wearflushed as well as gear wear.
Silicon(Si)- Indicates poor air filtration, possible fuel derivative
Sulphur(S)- May indicate the presence of clay based
(bentonite) greases(bentonite) greases
Sodium(Na)- With Mg indicates the presence of sea water
contamination, possible coolant system and fuel derivative
Vanadium(V)- Usually indicates the presence of fuel oilVanadium(V) Usually indicates the presence of fuel oil
3/14/2014 30
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
31. Alkalinity and acidityAlkalinity and acidity
TBN-TOTAL BASE NUMBER- measure of alkaline additives available
for the neutralisation of acids from combustion products and oxidation.
Level governed by type of fuelLevel governed by type of fuel.
For crosshead engines the TBN will tend to rise due to contamination
by liner lubrication, it should not be allowed to raise more than twice
that of the new charge.
A id th TBN f f h il h ld b t l tAs a guide, the TBN of fresh oil should be at least:
10 x fuel sulphur content (%) for trunk piston engines
(10mgKOH/g)
20 x fuel sulphur content (%) for cyl oil in x-head engines20 x fuel sulphur content (%) for cyl oil in x head engines
(20mgKOH/g)
A simple shipboard go,no-go test is available for measuring the TBN, it
involves the addition of an indicator and acid reagent to a 30ml
sample The quantify of acid reagent added is determined by thesample. The quantify of acid reagent added is determined by the
required level of TBN, for TBN2.5 0.5ml are added, for TBN20 4ml is
added. After three minutes the colour is checked against a chart
Purple:Good level of TBN
Green:Borderline
Yellow:Low level of TBN
3/14/2014 31
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
32. TAN TOTAL ACID NUMBER f i id d tTAN-TOTAL ACID NUMBER-measure of organic acid and strong
acid content of oil. Where SAN is nil, the TAN represents the acidity
in the oil due to both the acids in the additives and the oxidation of
the hydrocarbons in the oil. The TAN of fresh oils varies with oil type,
d t d t li b ith A hi h TAN i di t th t iland tends to climb with age. A high TAN may indicate that an oil
should be changed or freshened by top up. A high TAN may be
accompanied with increased viscosity.
SAN-STRONG ACID NUMBER-indicates the presence of strong,p g,
highly corrosive (inorganic) acids, usually formed from combustion
products. If SAN is not zero the oil should be changed immediately
Oil cleanliness
IC INDEX OF COMBUSTION measures soot loading of oilIC-INDEX OF COMBUSTION-measures soot loading of oil
MD-MERIT OF DISPERSANCY-Ability of an oil to disperse
contaminants, such as soot, wear debris and water and thereby carry
them away from the critical areas. Measured by oil blot test and
h ld t b ll d t f ll b l 50should not be allowed to fall below 50
DP-DEMERIT POINTS- combination of IC and MD: the lower the
value, the healthier is the condition of the oil
3/14/2014 32
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
33. Shipboard water content test
1 Th fl k i fill d t k 'A' ith k1. The flask is filled to mark 'A' with kerosene
2. A capsule of reagent (calcium hydride) is added.
Any water in the kerosene will react with the
calcium hydride and any gas vented off.y y g
3. he container is topped to mark 'B' with sample oil
4. The screw valve and cap are closed.
5. The flask is inverted and shaken
6. After 2 minutes the screw valve is opened. The
hydrogen produced by the reaction between the
reagent and water exerts a pressure which forces
the kerosene through the open valve into thethe kerosene through the open valve into the
graduated cylinder. The amount discharged is
proportional to the water content in the oil sample.
7. If the water content is greater than 1.5% then the
t t h ld b t d thi ti i lltest should be repeated this time using a smaller
sample by filling only to mark 'C'.The second scale
on the graduated cylinder should then be used.
8. If water is detected its type, sea or fresh , shouldyp , ,
then be determined by use of a special reagent the
water
3/14/2014 33
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy,
Bangladesh
34. Types of Lubrication
C id i th t f ti b t iConsidering the nature of motion between moving or
sliding surfaces, there are different types of mechanisms
by which the lubrication is done They are:by which the lubrication is done. They are:
1. Hydrodynamic lubrication or thick film lubrication
2. Hydrostatic lubricationy
3. Boundary lubrication or thin film lubrication
4. Extreme pressure lubrication
3/14/2014 34
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
36. Hydrodynamic lubrication depends on:
relative speed between the surfaces,
‐ oil viscosity,
‐ load, andload, and
clearance between the moving or sliding surfaces.
In hydrodynamic lubrication the lube oil film thickness is greater
than outlet pressure at the inlet increases quickly remains fairlythan outlet, pressure at the inlet increases quickly, remains fairly
steady having a maximum value a little to the outside of the
bearing center line, and then decreases quickly to zero at the
outlet.
3/14/2014 36
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
39. Elastohydrodynamic,
This is the type of lubrication used with rollingThis is the type of lubrication used with rolling
element bearings. To clarify, the material of the
running surface deforms under high pressure as theg g p
rolling element passes over it. The oil wedge forms
in this deformation.
(i) Deformation and increased viscosity with
pressure are involved
(ii) Frictional coefficient = 0 05(ii) Frictional coefficient = 0.05
(iii) film thickness less than Hydrodynamic
3/14/2014 39
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
40. 2. Hydrostatic Lubrication:
Hydrostatic lubrication is essentially a form of hydrodynamic
l b i ti i hi h th t l f t d blubrication in which the metal surfaces are separated by a
complete film of oil, but instead of being self‐generated, the
separating pressure is supplied by an external oil pump.
Hydrostatic lubrication depends on the inlet pressure of lube oil
and clearance between the metal surfaces, whereas
hydrodynamic lubrication it depends on the relative speedhydrodynamic lubrication it depends on the relative speed
between the surfaces, oil viscosity, load on the surfaces, and
clearance between the moving surfaces.
3/14/2014 40
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
41. Example: the cross head pin bearing or gudgeon pin bearing
in two stroke engines employs this hydrostatic lubrication
mechanism. In the cross head bearing, the load is very high
and the motion is not continuous as the bearing oscillation isa d t e ot o s ot co t uous as t e bea g osc at o s
fairly short. Thus hydrodynamic lubrication cannot be
achieved. Under such conditions, hydrostatic lubrication offers
the advantagethe advantage.
Hydrostatic Lubrication
3/14/2014 41
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
42. 3 Boundary Lubrication or Thin Film Lubrication3. Boundary Lubrication or Thin Film Lubrication
Boundary lubrication exists when the operating condition are
such that it is not possible to establish a full fluid condition,
ti l l t l l ti d b t th iparticularly at low relative speeds between the moving or
sliding surfaces.
The oil film thickness may be reduced to such a degreey g
that metal to metal contact occurs between the moving
urfaces. The oil film thickness is so small that oiliness
becomes predominant for boundary lubricationbecomes predominant for boundary lubrication.
Boundary lubrication happens when,
•A shaft starts moving from rest.
Th d i l•The speed is very low.
•The load is very high.
•Viscosity of the lubricant is too low.y
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Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
43. Examples for boundary lubrication:
Guide and guide shoe in two stroke engine.
Lubrication of the journal bearing in diesel engines (mainly duringLubrication of the journal bearing in diesel engines (mainly during
starting and stopping of engine).
Piston rings and when cylinder liner is at TDC and BDC position
h th i t di ti h d if th l ti d iwhen the piston direction changes and if the relative speed is very
slow.
Boundary Lubrication
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Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
44. A thin lubricant should have high viscosity indexA thin lubricant should have high viscosity index,
good resistance to heat and oxidation, good
oiliness and low pour point.
Velocity
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh 443/14/2014
45. 4. Extreme Pressure Lubrication
When the moving or sliding surfaces are under very high pressure
and speed, a high local temperature is attained. Under such
condition liquid lubricant fails to stick to the moving parts and maycondition, liquid lubricant fails to stick to the moving parts and may
decompose and even vaporize. To meet this extreme pressure
condition, special additives are added to the minerals oils. These are
called “extreme pressure lubrication.” These additives form on the
metal surfaces more durable films capable of withstanding high loads
and high temperature. Additives are organic compounds like chlorine g p g p
(as in chlorinated esters), sulphur (as in sulphurized oils), and
phosphorus (as in tricresyl phosphate).
The Extreme pressure Additives are the organic compounds
possessing the active radicals or groups such as chlorine, sulphur ,
phosphorus etc. These compounds react with metallic surfaces at
high temperature to form metallic chlorides.
3/14/2014 45
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
47. Stresses on Lube oilStresses on Lube oil
The main stresses experienced by Lube oils in diesel engines operating
on heavy fuel oils are expressed as follows
A id St C d b l h i d id ti id Thi l d tAcid Stress‐ Caused by sulphuric and oxidation acids. This leads to
increased corrosive wear, deposits, reduced Base Number and shorter oil
life.Rapid depletion of the BN is the clearest sign of oil stress
h l/ d h d b l d l dThermal/Oxidative stress‐This caused by elevated temperatures leading
to increased rates of thermal/oxidative breakdown of lubricant and fuel.
This leads to increased levels of deposits, sludges, corrosive wear of
bearing material, oil thickening and reduced oil life. In addition deposits
on the under crown side of the piston can lead to increased hot corosion
on the piston.
Asphaltene Stress‐This caused by fuel contamination of the lube oil and
can lead to increased levels of deposits, sludges, lacquers, oil thickening
and reduced oil life. In addition deposits on the under crown side of the
piston can lead to increased hot corosion on the piston
3/14/2014 47
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
48. Various Factors of Lubricating Oil:g
OXIDATION
‐ Oxidation degrades the lube oil producing sludges, varnishes and
resins Presence of moisture and some metals particularly copperresins. Presence of moisture, and some metals particularly copper
tend to act as a catalyst. Once oxidation starts, deterioration of the
properties of the oil is rapid.
‐ Oxidation reduces its effectiveness as a lubricant. Oxidation will
also cause deposits which can block passage ways and coat working
parts. The rate of oxidation will depend upon temperature, the p p p p ,
higher the temperature the more rapid the rate. Anti oxidants are
available which reduce the rate, also additional properties can be
achieved by the use of additivesachieved by the use of additives.
3/14/2014 48
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
49. ‐‐ Most of the chemicals found in an oil will react more or less with
oxygen, The effects of this oxidation is always undesirable. Hence, a
major objective of the refining process of a mineral oil is to remove j j g p
those hydrocarbons i.e. the aromatics, the small amount of
unsaturates together with molecules containing sulphur, oxygen and
nitrogennitrogen.
‐ The use of anti‐oxidants make a slightly better balance although
there usefulness is limited.
Tin based white metal is susceptible to hardening as an oxide layers‐ Tin based white metal is susceptible to hardening as an oxide layers
from on the surface. These tin oxides are a grey‐black in appearance
and are extremely hard. There formation reduces the bearing
l h id l i hi k h h i i l hi lclearance as the oxide layer is thicker than the original white metal
material from which it formed. The oxide has a lower coefficient of
friction than the original white metal but it will cause problems if it
brakes up as fragments will become embedded edge on in the white
metal and can score the pin. .
3/14/2014 49
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
50. Emulsification
‐ This occurs due to water contamination; also, contamination with
grease, fatty oils, varnish, paint and rust preventers containing fatty
products can also promote emulsification.
- The presence of an emulsion can be detected by a general
cloudiness of the sample. Salt water emulsifies very easily and
should be avoided.
- Water entrained in the oil supplied to a journal bearing can lead
to loss of oil wedge, rub and failure.
Fresh water contamination whilst not in itself dangerous can lead
to rusting. The iron oxides catalyses the oil to form sludge's. Theg y g
additives in the oil can leach out to change the water into an
electrolyte.
- Salt water contamination is very serious as it causes tin oxidey
corrosion, and also leads to electrochemical attack on the tin
matrix in the white metal. The sea water act as then electrolyte.
A major problem of water within a lub oil is where the mix enters aA major problem of water within a lub oil is where the mix enters a
bearing, here it is possible for the water to be adiabatically heated
causing it to flash off collapsing the oil wedge.3/14/2014 50
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
51. THERMAL DEGRADATION:
Under high temperatures an oil is liable to thermal degradation
which causes discoloration and changes the viscosity. Additives
cannot change an oils susceptibility to this degradation.cannot change an oils susceptibility to this degradation.
RECHARGING
When recharging no more than 10 % of the working charge shouldWhen recharging no more than 10 % of the working charge should
be topped up due to heavy sludgeing that can occur due to the
heavy precipitation of the sludge.
EP ADDITIVE OILS
Can assist in healing of damaged gear surfaces but should be used
as a temporary measure only due to risk of side effects.as a temporary measure only due to risk of side effects.
3/14/2014 51
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
52. Contamination of Lube oil in Diesel Engine:Contamination of Lube oil in Diesel Engine:
Water
Water from,
1 bil '1.bilge's
2.Jackets
3.Sea via coolers
4.leaky seals or washing in purifiers
5.Condensation
Problems caused by water contamination,Problems caused by water contamination,
•Water leads to corrosion especially if there is sulphur
present due to fuel contamination
forms emulsions which are not capable of withstanding•forms emulsions which are not capable of withstanding
high loads
•removes water soluble additives when centrifuged out
•leads to possible bacterial attack
3/14/2014 52
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
53. Fuel
May be heavy residual or light diesel/gas oil and can be sourced toMay be heavy residual or light diesel/gas oil and can be sourced to
faulty to cylinder combustion or faulty seals on fuel p/ps.
Problems
Increases viscosity for hfo reduces viscosity for D O- Increases viscosity for hfo, reduces viscosity for D.O.
- Reduces flashpoint
- Introduces impurities such as sulphur
Dil t l b il h i l titi- Dilutes lub oil when in large quantities.
Solid impurities
b f th li d b ti ti l l fcarbon from the cylinder combustion process, particularly of
importance with trunk piston engines but also for crosshead engines
with inefficient diaphragm. The carbon can lead to restrictions and
f f Sblockages of oil ways causing bearing failure. Straight mineral oils
hold 1% carbon in suspension, dispersant oils hold about 5%.
3/14/2014 53
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
54. Bacterial attack:
Certain bacteria will attack oil but water must be present TheCertain bacteria will attack oil but water must be present. The
bacteria may exist in a dormant state in the oil but water is
required if they are to reproduce.. The bacteria digest the oil
causing breakdown emulsions to be formed, acidity
increases, dead bacteria block filters and corrosive films form
on working surfaces.on working surfaces.
In summary their must be three essential conditions for
microbiological growth;
1 There must be a source of carbon present in the oil1. There must be a source of carbon- present in the oil
2. There must be some bacteria or fungal spores present-
these are almost universally present in the atmosphere.
3. There must be free water present.
3/14/2014 54
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
55. Two other factors which encourage the growth of bacteria:
1. A slight acidity in the water (pH 5 or 6) and
2. A slightly raised temperature (20 to 40oC) which can lead to2. A slightly raised temperature (20 to 40 C) which can lead to
rapid growth.
Biocide additives are available but they are not always compatible
with other desired additives and can lead to large organicwith other desired additives and can lead to large organic
blockages if treated in the machinery. The best solution is to avoid
the presence of water. If mild attack takes place the oil may be
heated in the renovating tank to above 90oC for 24hrs before being
returned to the sump via the centrifugal separator. For a severe
attack the only solution is complete replacement of the charge y p p g
followed by sterilization of the system. It may be noted that on
replenishment the bacteria may be present in a dormant state in
the new chargethe new charge.
3/14/2014 55
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
56. LUBRICATION FEATURES OF A LARGE DIESEL ENGINELUBRICATION FEATURES OF A LARGE DIESEL ENGINE
• In some engines such as long and super long stroke engines, the
piston is not directly connected to the crank pin via a connectingpiston is not directly connected to the crank pin via a connecting
rod.
• The piston has a piston rod extending from the bottom of theThe piston has a piston rod extending from the bottom of the
piston.
• The piston rod is then connected to the connecting rod at the
h d b icrosshead bearing.
• The crosshead bearing has a to and fro motion and therefore a
continuous hydrodynamic film cannot formcontinuous hydrodynamic film cannot form.
• Therefore oil has to be pumped to the crosshead bearing at a
predetermined pressure in order to take the loads of compression
56
and combustion.
• The crosshead is connected to the crank pin via a connecting rod.3/14/2014
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
57. Piston
Piston rod
Piston rings
Piston skirt
Pl tf ti li d Piston rod
Stuffing box
Platform separating cylinder
from crank case
Crosshead, crosshead
bearing (reciprocating)
Connecting rod
Oil pumped at
a certain
pressure
Crank pin, bottom end
bearing (rotatory motion)
Journal journal bearing
57
Journal, journal bearing
(rotatory motion)
Web
3/14/2014
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
58. Problems caused by stuffing box leakage oil enteringProblems caused by stuffing box leakage oil entering
crankcase:
Low speed engines are particularly at risk from crankcase
l b i t t i ti d b li d il d i t thlubricant contamination caused by cylinder oil drainage past the
piston rod gland and combustion products. This can lead to
severe damage of engine crankcase components and reduction
of life of oil which is normally expected to last the lifetime.
There has been a general increase in the viscosity and Base
number of crankcase oils over recent years particularly fory p y
engines built since the early 1980's. Increased alkalinity, viscosity
and insolubles, fuel derived elements such as vanadium and oil
additive derived elements such as calcium, suggest that theadditive derived elements such as calcium, suggest that the
contamination is from the cylinder oil drainage.
Deterioration of the crankcase oil has led to the expensive
necessity of replacing up to 50% of the sump this is particularlynecessity of replacing up to 50% of the sump, this is particularly
of concern as it is often only a temporary measure.
3/14/2014 58
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
59. Four causes are put forward:Four causes are put forward:
1. New crankcase oil contaminated with new cylinder oil-unlikely
2. Cylinder oil drainings being recycled and returned to the sump-very
likely as it is a common practice to purify oil leaking through the gland,y p p y g g g ,
tests done on this purified oil found high amounts of insolubles.
3. Leakage past rod gland- very likely, high pressure scavenge air can
blow cylinder oil and dirt past the top scrapper ring and sealing ringsy p p pp g g g
into the piston rod drain tank, and even possibly directly into the sump.
A problem that worsens with age and wear.
4. Leakage of exhaust valve lubrication system-unlikely
The most likely cause for contamination is leakage past the
piston rod. It is seen that maintenance of the stuffing box is of the
utmost importance. Tell tales and drainage lines should be proved free
and use of oil drained from the uppermost drain should not be allowed
even after purification due to the high level of contamination which can
destroy the properties of the oil in the sump.
3/14/2014 59
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
60. Cylinder liner lubricationCylinder liner lubrication
The type of Cyl. Lub oil required will depend upon the cylinder
conditions and the engine design e.g crosshead or trunk piston.
Ho e er the propert req irements are basicall the same b t illHowever, the property requirements are basically the same but will
vary in degree depending upon the fuel and operating conditions.
In some engines, lubricating oil in the cylinder is different from the oil
supplied to the other bearings.
The cylinder oil contains additives to withstand the high temperatures
and contaminants from combustion products.
The oil is slightly basic in nature to counter the acids formed from
combustioncombustion.
Scraper rings spread the oil over the liner surface.
Lub. oil is usually injected between the two scraper rings.
Oil is injected at a predetermined period during the downward stroke.O s jected at a p edete ed pe od du g t e do a d st o e
Before starting, oil is pumped into the liner by manual priming
methods.
After starting, the oil pump is driven by the engine through a cam
shaft
60
shaft.
3/14/2014
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
61. CYLINDER LUB OIL PROPERTIESCYLINDER LUB OIL PROPERTIES
Normal properties required are:
1 adequate viscosity at working temperature so that the oil1. adequate viscosity at working temperature so that the oil
spreads over the liner surface to provide a tough film which
resists the scraper action of the piston rings
2. the oil must provide an effective seal between the rings and
liliner
3. only a soft deposit must be formed when the oil burns
4. alkalinity level (total base number or TBN) must match the
acidity of the oil being burntacidity of the oil being burnt
5. detergent and dispersant properties are required in order to hold
deposits in suspension and thus keep surfaces clean
Behaviour depends upon the temperature of the liner, piston crown
d i t i TBN d d t l l li k d Thiand piston rings. TBN and detergency are closely linked. This can
have an adverse effect when running on lighter fuels with lower
sulphur content for any period of time. Coke deposits are can
increase.
3/14/2014 61
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
62. Cylinder liner
Compression rings
Scraper rings
Oil i j i
p g
Oil injection passage
Piston
Injection points
Cylinder oil
pump/lubricator
Handle
62
Camshaft
3/14/2014
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
63. Trunk type engine (no piston rod)‐
Splash type lubricationSplash type lubrication
Piston ringsCylinder liner Piston rings
Gudgeon pin
y
Oil is picked up by the webs
while rotating, and splashed
onto the piston and liner
Crank pin, bottom end
bearing (rotatory
motion)
Connecting rod
Journal, journal bearingJournal, journal bearing
(rotatory motion)
Web extension
63
Web
Web extension
Oil
3/14/2014
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
66. Distribution within a journal bearing
If the maximum radial clearance is Cr
then Cr = e + Hm
where e is the eccentricity between the shaft
and bearing centre line and Hm is the minimumand bearing centre line and Hm is the minimum
clearance (oil film thickness)
an eccentricity factor can be calculated from
n = e / Cr
Factors involved with the eccentricity factor n
are:
minimum oil film thickness,
journal attitude angle- journal attitude angle,
pressure distribution,
peak pressure angle,
friction,friction,
horsepower loss and
oil flow through the loaded region.
The latter three determine the temperature of
the bearing which for high speed bearings can
be a limiting factor.
3/14/2014 66
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
68. Lubrication systemLubrication system
• TG‐ Temperature gauge
• PG‐ Pressure gauge
ENGINE Shaft
TG PG
Bearings
Cooler
PG
PG
TG
Storage tank Pump
Filter
PG
68
68
Filter
3/14/2014
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
69. Engine sump
ENGINE Shaft Bearing
C ti f
Storage tank/sumpPump
Connection for
filling the tank
• The storage tank usually forms the bottom-most compartment of the engine.
strainer
• It is also sometimes known as the sump.
• Oil from the sump is usually transported to the bearings by an engine driven
pump or an independently electric motor driven pump that transports the oil top p p y p p p
the journal bearings.
• Through passages drilled in the crank shaft and webs, it is transported to the
crank pin.
69
p
• Usually a strainer is provided on the suction side of the pump to prevent large
contaminant particles from damaging the pump and bearings.
3/14/2014
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
70. Oil cooler‐ tube and shell type
Oil in
TG
TG
TG
PG
Water in Water out
Oil out
TG
PG PG
PG
Oil out
• In this case, cooling water flows through the tubes.
• Oil flows in the shell around the tubes and passes the heat to the water• Oil flows in the shell around the tubes and passes the heat to the water.
• The in/out temperatures of the oil and water are to be monitored.
• Oil pressure is always kept above water pressure to prevent water
70
contamination of oil
• However, if there is a leak oil is lost and the sump level is therefore to be
monitored regularly3/14/2014
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
71. Engine lubrication system
Some adverse situations:
• TG- Temperature gauge
• PG- Pressure gauge
Some adverse situations:
•Oil inlet pressure to engine LOW
•Oil outlet temperature from engine HIGH
ENGINE Shaft
TG PG
•Oil outlet temperature from cooler HIGH
Cooler
Bearings
PG
TG
PG
TG
71
71
Storage tank Pump
Filter
3/14/2014
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
72. Properties ideal for bearings:
1 Soluble for high speed fluid film hydrodynamic1. Soluble for high speed fluid film hydrodynamic
lubrication, hence, low viscosity with reduced oil film
friction.
2. moderate bearing loads
3. improved heat transfer behavior
4. corrosion protection
5. cooling
6 low friction6. low friction
7. good low temperature viscosity
8. good high temperature viscosity8. good high temperature viscosity
3/14/2014 72
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
73. PROPERTIES IDEAL FOR GEAR CASE:
• high film strength to prevent metal to metal contact.
H hi h i i dh i i lidi dHence, high viscosity adhesive to resist sliding and
centrifugal forces
• corrosion protectionp
• cooling
• reduces friction
• good low tempo viscosity• good low tempo viscosity
• good high tempo viscosity The thicker the oil film the
greater the cushioning against shocks. Also less tendency
f it f ti b h d li ti i kfor pit formation by hydraulic action in cracks,
• sound damping properties with cushioning effects
• antifoam propertiesp p
3/14/2014 73
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh
74. Turbine oilTurbine oil
Compromise between above two requirements
1. Generally a good quality refined mineral oil derived
f ff i b t k d ith ifrom paraffanic base stock used with various
additives including EP additives for highly loaded
gearing.
2. Anti-foaming properties important
3/14/2014 74
Mohd. Hanif Dewan, Senior Engg. Lecturer,
International Maritime Academy, Bangladesh