29-08-2014, 11:31 AM
I have done my six months trainig at Sonalika Hoshiarpur,Punjab.I done two projects there first is on masking which is to provide temporary protection to an area while the adjacent area being worked on.As tractor require masking on various parts so the existing method used in sonalika was masking tape.Instead of using masking tape i suggest to use masking cap which is more advantages than masking tape as it require less manpower,less cost and less time consuming.My second project was on improvement of material handling of engine assembly .The tools used for this was 5'S,Kaizen,3'M technique.
SIX MONTHS INDUSTRIAL TRAINING REPORT AT INTERNATIONAL TRACTORS LIMITED HOSHIARPUR, PUNJAB. Submitted in Partial Fulfillment for award of Degree of Bachelor of Technology In Mechanical Engineering From Punjab Technical University, Jalandhar. Submitted By SOURABH ARORA 100491131051 Department of Mechanical Engineering Ludhiana College of Engineering and Technology Katani Kalan, Ludhiana. May 2014 ACKNOWLEDGEMENT Acknowledging any one in mere words is a very difficult job. I feel grateful to all the people who helped me in one way or the other during this project, with their able guidance and valuable advice. All this while, I have gained wonderful learning experience about consumer behavior, industry responses & working of an esteem global organization. I would like to thank Mr. L.D.Mittal who gave me an opportunity to do my six months training at International Tractors Limited, Hoshiarpur (Punjab). I wish to express my deep sense of indebtedness & gratitude to my esteemed guide Mr. S.K Arora for his keen interest, competent and generous help, and valuable guidance & also for his constant encouragement throughout the period of this study. I also appreciate the support of Mr. Sanjeev Arora, Mr. Manish Vats, Mr. Harwinder Singh and other staff members and the workers from whom I learnt a lot in the process of training and whose cooperation enriched me with synergistic benefits. My respect and heartiest thanks are to all my teachers- H.O.D Mr. Y.N Gupta and Training Incharge for their support and cooperation. I would like to thank my parents and my friends for their help. CONTENTS Cover page……………………..…………………………………………………. i Certificate... ii Acknowledgement... iii Contents... .. iv Materials and method…………………………………………………………v Result and discussion………………………………………………………vi Conclusion……………………...……………………………………………... vii References………..…………………………………………………………… viii Page No. Chapter 1 Introduction 1.1. Organizational Overview...1 1.2. Success Stories………………………………………...2 1.3. International Tractors Limited………………………...4 1.4. ISO 14001 & ISO 9001:2000 Certifications…………………..8 1.5. International Cars & Motors Limited…………………………10 1.6. Sonalika Agriculture Corporation……………………………..12 1.7. Joint Ventures………………………………………...13 1.8. Competitors Companies……………………………..15 1.9. Drawbacks of Competitors of Sonalika……………………..…17 Chapter 2 Tractor Assembly Shop 2.1. Introduction……………………………………………………19 2.2. Engine Assembly………………………………………………20 2.2.1. Introduction………………………………………..20 2.2.2. Operating Instruction………………………………23 2.2.3. Components of Engine……………………………..25 2.3. Differential Housing Assembly……………………...40 2.3.1. Introduction……………………………………...40 2.3.2. Main parts of differential housing………………….42 2.3.3. Testing Of Differential……………………………..46 2.4. Rear Cover Assembly…………………………………………..47 2.4.1. Introduction………………………………………….47 2.4.2. The main components of rear cover assembly……….49 2.5. Gear Box Assembly……………………………………………..52 2.5.1. Introduction…………………………………………..52 2.5.2. Main components of gearbox…………………………53 Chapter 3 Projects Undertaken 3.1. Project no. 1 3.1.1. Objective…………………………………………………….57 3.1.2. Introduction…………………………………………………57 3.1.3. Tools Used…………………………………………………..62 3.2. Project no. 2 3.2.1. Objective…………………………………………………….84 3.2.2. Introduction…………………………………………………84 3.2.3. Types Of Masking………………………………………..84 Chapter 4 Results & Discussion…………………………………….96 Chapter 5 Conclusion………………………………………………..97 References…...98 CHAPTER-1 1.1 Introduction To Organization:- Sonalika Group is contributing to green revolution in India Since 1969. Initially it started with Farm Equipments and Machinery. Brand name of the group products is "SONALIKA". Market share in Farm Equipments is 80 % in India. Group turnover is 220 Million USD (INR 1000 Crores). Sonalika Group is one of the top five tractor manufacturers in India. Apart from tractors its product line includes multi utility vehicles, three wheelers, engines , Hydraulic Systems , Casting , Forging , Brake System , Automotive components manufacturing and various farm equipments and implements. Sonalika group since the inception has tried to understand customers need to be able to facilitate them with its value for money products. The company has a state of art manufacturing facilities, spread in acres, located in the pollution free suburbs of Punjab and Himachal Pradesh. Sonalika is also an environmentally responsible corporate citizen and has developed in-house, the vehicle engines that confirm to Bharat II Norms. It is now in the process of developing the Bharat III engines for its advanced products. No wonder Sonalika products have created a niche for themselves not only in India but also in foreign markets including France, Zimbabwe and many of the South-Asian countries. An average growth rate of 30% makes it one of the fastest growing corporate in India. It also happens to be one of the very few debt free companies in the world. It employs about 2500 people including some of the renowned names in the industry. The company works on the maxims of low production cost and clean and safe environment. Such efforts have fetched the company the accreditations like ISO 9001:2000 and ISO 14001. 1.2 SUCCESS STORIES :- CMERI Govt. of India Transfers Design and Technology to Sonalika Sonalika group under the stewardship to Shri L.D. Mittal, (Chairman) has made rapid strides within a short span of 9 years. It has not only made its presence felt in the tractor Industry but has made in-roads into the market share of popular brands. Its valued and satisfied customers are multiplying and have crossed 10,0000 mark in year 2004. According to Shri Mittal, this phenomenal growth is the result of hard work coupled with dedication at all levels. On the top of it, company has never compromised on quality. This is precisely the secret of success of the company. Shri Mittal further states "We have been after a class technology so that Indian farmers get the best value for their hard earned money." MERI (Central Mechanical Engineering Research Institute ) Govt. of India, which has many first to its credit in many fields, has been helping Sonalika a lot in enriching the company with technological advancements based on their strenuous efforts and research .A function was held at the Vigayan Bhavan in New Delhi and Shri Mittal was applauded for his great contribution in farm mechanization. Shri R.A. Masheikar F.R.S. Director General, CSIR & Secretary-Govt. of India, Department of Scientific & Industrial Research stated that if there were a few more " Mr. L.D. Mittal " the country's face would be different. Shri Mittal in his short speech thanked the CMERI for the good words attribute to him and suggested that CMERI should come forward for facilitating air spraying of insecticides, improved combine Harvester and mini Tractor. These suggestions are receiving the attention of scientists across Durgapur and Ludhiana under the supervision of CMERI. On this occasion, CMERI transferred technology for Sonalika Tractors for all models ranging from 32 HP to 60 HP. Honorable Former Prime Minster Refers to Sonalika Tractor in Diamond Jubilee Celebrations of CSIR, Govt. of India Honorable Former Prime Minister, Sh. Atal Bihari Vajpayee said to the science & Technology Institutions to go to masses and make them aware of their activities while inaugurating the Diamond Jubilee celebrations of the council of Scientific and Industrial Research (CSIR). He said to CSIR to bridge the awareness gap between the people and CSIR. Former Prime Minister , said while discussing the CSIR's inventions & developments related to common man, "Today when a farmer uses the Sonalika Tractor or over two lacks women use contraceptive pill `Sahelli' for family planning or any doctor advices his malaria patient to take Emel or when a rural person uses Mark-II hand pump, how many of them know that these are inventions of CSIR".Sonalika Tractor is marching ahead on the path of success in which CSIR's contribution is very crucial. Sonalika is the only Tractor in which technology of CSIR, Govt. of India has been used and which is produced at the ultra-modern plant of global Tractor company Sonalika. Resultantly, Sonalika has become the first choice of Indian farmers. On close observation of the features of Sonalika, one will find that at one hand it is fuel efficient, on other hand it has got special position in pulling power. The number of satisfied and proud customers is increasing day by day and has crossed the figure of 100000. After all, there is something exclusive and unique so much of prestige in just 9 Years. 1.3 International Tractors Limited:- Fig 1.1 International Tractors Limited was incorporated on October 17, 1995 for the manufacture of Tractors and has since then built a distinct position for itself in the Tractor industry. ITL is manufacturing various Tractors of Sonalika brand between 30 H.P. to 75 H.P, and CERES brand between 60HP to 90HP. The Tractors manufactured by the company have secured a reputation of performance, quality and reliability in the market because of their maximum pulling power, minimum fuel consumption and Emission. all this makes ITL the fifth largest tractor selling company in India and the number one company in Nepal. These tractors are also exported to various other countries also including France, South Africa, Australia, Zimbabwe, Sri Lanka, Canada, Nepal, and Bangladesh etc. The company's marketing efforts are promoted by the network of 600 Dealers ,400 Sub dealers and 50 Stockiest supervised by various regional sales offices. Such a networking has enabled the company to grow like a well-knit family whose roots lie in its customers, who have been providing constant feedback and support to allow the company to turn their dreams into products. It is a matter of pride and honor for us that our Manufacturing Process, Quality Control Systems and Research & Development facilities are ISO- 9001:2000 Certified by the Joint Accreditation System of Australia and New Zealand. We are the first Tractor manufacturing company in the country to be accredited with ISO-14001. It bears testimony to the fact that company is having world-class R&D facilities, maintaining controls and systems of International Standards and Environmental norms. We are also the first Tractor manufacturers in the country producing 50 & 60 HP Tractors fitted with diesel engines manufactured In-House, meeting Bharat II norms of Smoke & Mass Emission. These engines have been tested and certified by ARAI, Pune. United States Environmental Norms Agency, Washington DC has also certified our Engines. These certifications enabled SONALIKA Tractors to enter into World Market. All the models of Tractors and Combines Harvesters manufactured by us are tested & approved by Central Farm Machinery and Tractors Training & Testing Institute, Budni (MP) India, (the Government of India institute authorized for issuing test reports). Recently SONALIKA Tractors have been awarded "The Best Quality Award (2002-03)" by the Govt of India. Sonalika International Tractors have also been approved for subsidy under various schemes by Ministry of Agriculture, Govt. of INDIA. A number of banks have approved Sonalika Tractor for financing and entering into a tie Up for easy financing. • ITL has been one of the first few companies to get ISO-9001, ISO-14001 and TS Certifications. • ITL got ITID (Institute of Trade & Indl. Development) Quality Excellence Award in 2002. • ITL’s market share increased to 11% (Approx.) as on 31.03.2006. The company maintained 3rd Rank in the tractor industry in terms of volume and market share. It surpassed Eicher & HMT (old Players), John Deere, New Holland and Escorts (Multinationals having long international standing). • The company has developed a diesel engine which is almost smoke free & has been approved by U.S Environment Protection Agency, Washington D.C. Company has also increased its production of diesel engine up to 100 engines a day. Fig 1.2 (annual prod.) • The company has made rapid strides in the tractor marketing and sold more than 130,000 tractors so far. • ITL is one of the first few companies to have implemented modern & sophisticated Product Data Management system called Metaphase; also it implemented Enterprise Resource Planning System – SAP way back in 2001. Fig 1.3 Fig 1.4 Fig 1.5 Fig 1.6 1.4 ISO 14001 & ISO 9001:2000 Certifications:- Sonalika has also been certified as ISO 14001 which is another golden feather in Company's Cap and another stamp of quality. It is the first Tractor manufacturing company in the country to be accredited with ISO-14001. Fig 1.7 International Tractors Ltd. with Sonalika brand of tractors have been certified as ISO 9001 issued by International Standards Organization. This certification can be earned by those organizations only who can establish and demonstrate strict compliance of quality systems prescribed under ISO 9001 as highest level of certification under which the organizations possess capabilitiesin the area of design and development and in manufacturing and marketing functions. It is indeed a great honor for the International Tractors Ltd. to have achieved this distinction that too within short span of its inception. It is the 2nd such company in India. which has received this certification The scope of registration covers design, development, production and installation. The registration is a quality mark. Sonalika has also been certified as ISO 14001 which is another golden feather in Company's Cap and another stamp of quality. Fig 1.8 1.5 INTERNATIONAL CARS AND MOTOR LTD. :- From tractor to utility vehicle 'All for one' human nature says it all. Utility, comfort, luxury and more…!! Today with the changing times, the needs and expectations of the customer are changing. He is technically well aware and economically conscious. He is not only concerned about his own safety but also about the safety of the environment. He wants a multi utility product. A product with Power and Punch. Therefore, we, at International Cars & Motors Limited developed a team that is constantly working with the dreams that vehicles inspire. Our team is exploring human ideas and desires by developing the ecstatic driving experience with intelligent technology - simple, safe and green. The BEAST in the waiting……..Rhino There's something special waiting and its Just for YOU. The whole new RHINO There's nothing more robust ! There's nothing more sporty ! There's nothing more elegant ! Stylish and roomy, just meant to cater to the requirements of YOUR Family. The Team ICML is the team of technocrats and design engineers working in the inspiring state of art environment. Every member of the team has vast experience in his or her respective field, which has enabled them to develop various prototypes in the short duration of time. Some of these have taken the final shape and are ready for launch. The Company will commence its commercial manufacturing operations at its ultra modern plant equipped with state-of-art facilities, which is under construction at Amb, Himachal Pradesh, very soon. Above is a model of harmoniously composed, simple, modern and environmental friendly plant. The objective is not only to attain top quality products, but also to meet today's requirements for productivity, safety, and environmental protection throughout the entire process of modern automobile creation - from the conceptual stage to final assembly. To add robust testing facility have been created for various kinds of quality tests and finally the road tests. The plant's location is also an advantage in itself. This is because of the income tax holiday for the industrial set-ups in the the state of Himachal Pradesh. Government also offers exemption on the excise duty on sales of vehicles from here. The cumulative effect of the above provides for substantial saving on the cost of the vehicle, which will add on the buying power of the customers. Fig 1.9 1.6 SONALIKA AGRICULTURE CORPORATION:- Fig 1.10 Fig 1.11 Fig 1.12 Multi Crop Thresher Sonalika Self Propelled Sonalika Potato Planter Sonalika Agro was established in 1971 to support the Indian farmers with mechanization technology to facilitate persistence of green revolution. Today, the company is supporting the farmers with world class farming equipment to ease the process of making the Green Revolution II, a dream come true. In the light of the company's mission, highly qualified and experienced staff is working as a family in the manufacturing facility at Hoshiarpur (Pb). This plant is equipped with advanced technology to develop, manufacture and test the modern products for the modern farmer. The company has a wide range of farm equipments and implements to facilitate the farmers in all kinds of farming activities. It has a large dealer network spread all over country and have approximately 80% share in Indian market of farm machinery .Its products are also exported to Asian & African countries through various export promotion counsels. Sonalika Agriculture Corporation manufactures the underlined implements and is having core expertise in manufacturing these: TABLE 1.1 Multi Crop Threshers Automatic Cutter (HARAMBA) Paddy Thresher Seed Cum Fertilizer Drill Maize Sheller Potato Planter Reaper Combine Harvester ETC. 1.7 JOINT VENTURES:- ITL went into collaboration with Renault agriculture of France in July 2000. Renault Agriculture is a subsidiary of the Renault Group with 51% stake owned by CLAAS, Germany. Renault Agriculture is the largest tractor manufacturing company in Europe. It produces tractors in the range of 50-250 HP, having worldwide distribution ands sales network. Fig 1.13 Renault Agriculture - ITL agreement results in the production of Ceres and Solis tractor under Sonalika brand name. With a turnover of more than € 637 billion (2002), Renault is one of the 30 largest companies in the world. Each year Renault produces over two million vehicles and employs over 140,000 people. Renault has alliance with NISSAN to complement the financial and and technical strengths bringing in synergic growth. CLAAS is a leading manufacturer of farming equipment with a global presence. It is the world market leader in forage harvester. Apart from the farming products CLAAS also produces hydraulic components and transmissions. CLAAS purchased 51% stake in Renault Agriculture in March 2003. It recorded the turnover of over 1,000 million € in the last financial year. Fig 1.14 1.8 COMPETITORS COMPANIES IN INDIA:- 1) Mahindra & Mahindra Plant: - Kandiwali (Maharashtra). 2) Tractor & farm equipment Plant: - Madurai. 3) Escorts LTD. Plant: - Faridabad (Haryana) 4) Mahindra & Mahindra (Swaraj Division) Plant: - Mohali (Punjab) 5) Hindustan machine tools LTD. Plant: - Pinjore (Haryana). 6) Tafe motors & tractors LTD Plant: - Mandideep (M.P.) 7) Fiat (New Holland tractors India pvt. LTD. Plant: - Noida (U.P.) 8) John Deer Tractors equipment LTD. Plant: - Pune (Maharastra) 9) Indofarm industries LTD. Plant: - Baddi (H.P.) 10) Force Motors Plant: - Pune (Maharastra) 11) Same Deutz Fahr Pvt LTD. Plant: - Ranipet (Tamil nadu) 12) Standard combines Pvt LTD Plant: - Barnali 13) Mahindra Gujarat tractors LTD Plant: - Baroda 14) Preet Tractors Plant: - Nabha (Pb.) 15) Ace Motors Plant: - Balabgarh Faridabad (Haryana) 1.9 DRAWBACKS OF COMPITITORS OF SONALIKA:- MAHINDRA & MAHINDRA:- This is a unbalanced tractor whose proof is that company given front weights in spite of which it gives front lifting which is very dangerous for operators. In the condition of sudden load tractor stops due to less TBU. Due to high engine RPM there is more wear and tear and needs frequent over-hauling Hydraulic operations are not performed correctly and problem of hydraulic hunting is normally observed which causes high diesel consumption and more tyre wear. Engine oil is less, which causes lesser cooling, and engine components get wear out early. TAFE:- Light weight tractor causes an increase in diesel consumption and more tyre wear. Gear section being lighter is a reason for inefficiency to trail heavy implements or trolley. Less ground clearance causes a hindrance in pudding and riding in rough terrain. Lesser wheelbase cause front lifting even on attaching a small implement. FARMTRAC:-High diesel consumption.Costly spares and high on maintenance cost.Having a lesser weight &length the tractor gives front lifting on attaching heavy implements. Rear side is light in weight causes more wear of tyre and lesser area coverage. SWARAJ:-High diesel consumption even on fewer loads.Tractors give smoke even on fewer loads.Having old technology manufacturing is continuously reducing sale.Costly spare parts and maintenance.Have gone through no changes in design and having a similar bonnet & fender gives a look like a tin box. JOHN DEERE:- Lesser wheelbase causes front lifting which is not good for driver’s security.Costly and non-availability of spare parts.At turning, there is a heavy drop in engine RPM, which cause load on engine and reduce engine life. NEW HOLLAND:-Speed reduction is not direct so power loss is grater.At turning there is a heavy drop in engine RPM which cause load on engine and reduce engine life. CHAPTER:- 2 TRACTOR ASSEMBLY SHOP 2.1 INTRODUCTION: - Tractor assembly shop is main shop of sonalika international tractor Ltd. In this shop the different machining parts, housing and other components which are finished or machined in other departments of the industry and other component which are purchased from outside are assembled here. Then assembled components like differential housing, gearboxes, rear covers, Trumpet housing and other housing are send to main line for Tractor assembly. In main Tractor assembly line tractors are send to paint shop through overhead endless chain rotating conveyor. It is supported from ceiling and has a fixed path to travel which saves valuable floor space. The arrangement is such that lifting mechanisum (with help of hook) lowers down for loading and unloading of tractors. Following are main phase of assembly: - (1) Engine assembly. (2) Differential housing assembly. (3) Rear cover assembly. (4) Gear box assembly. (5) Main line assembly phase. (6) Paint phase. (7) Assembly of accessories and inspection. 2.2 ENGINE ASSEMBLY :- Fig. 2.1 - (engine) 2.2.1 INTRODUCTION :- This is the most vital department of the industry as complete engines are assembled here. It provides a clean, tidy, dust free environment under controlled temperature conditions to the workers working on the assembly line. The assembly line is basically a belt conveyor with a series of mounting stations built upon it to mount the crankcase or engine block and carry on the assembly operations. The mounting is of such a type so the crankcase mounted on it can be swiveled to convenient angular positions while working on it. The crankcase mounted at one end of the conveyor eventually passes through each of the stages where workers keep on adding the components one by one and finally a completely assembled engine is obtained at the end of the assembly line. The components to be fitted are provided to the workers on the stands and shelves behind them. The belt conveyor keeps on moving continuously and a sensor fitted at the end of the line stops the line if any engine remains unloaded from the station at the end. Behind the assembly line there are specific machines namely: 1. Leakage test rig for water jacket cylinder head. 2. Valve lapping machine. 3. High pressure pipe cleaning machine. 4. Lube oil pump test rig. 5. Flywheel balancing machine. 6. Hydraulic press for press fitting of components. 7. Electric oven. 1. Working procedure for leakage test rig for water jacket cylinder head: • Slide the washed cylinder head onto the roller table and locate the testing ring on the dowel pin. • Drive the machine on auto cycle. • When green light glows on the tower lamp then the cylinder is ok and ready for next operation. 2. Working procedure for valve lapping machine: • Reaming the valve guide holes. • Cleaning and applying emery paste on the periphery of the valve. • Fixing up the valve onto the seat. • Placing and grinding it on the auto lap machine. • Cleaning the lapped seat and valve periphery. • Fitting up of the valves over the head. • Emery paste is used as the abrasive material and 2 cylinders can be ground at a time. 3. Working procedure for high pressure fuel pipe cleaning machine: • Cleaning medium is 20% engine oil + 80% diesel oil. • Removal of the plastic cap from the high pressure pipe and tighten it on machine holder. • Let the machine work for 10 minutes onto the high pressure line, flushing the bar at pulsating pressure. • After flushing remove the high pressure pipe and after fitting plastic cap send it for assembly. 4. Working procedure for lube oil pump test rig: • Oil pump is mounted onto the test rig. • Motor is switched on and the requisite RPM is set. • Heating of oil is carried out by switching on the heater. • Pressure and flow rate are observed on the gauges and checked as per the following table: • If the red light glows then test the leaking part of the head and reject the defective piece in inform the shift in charge. • Air pressure used: 4 kg/cm2 TABLE 2.1 Model: Pressure: Kg/cm2 Temperature: °C RPM: Flow: Lit./min. 3 cylinder 2 60 600 10±1 3 cylinder 2 60 1800 26±1 4 cylinder 2 60 600 13±1 4 cylinder 2 60 1800 36±1.5 5. Working procedure of flywheel balancing machine: Flywheel constitutes an important part of an engine balancing is as important as that for a crankshaft. An unbalanced flywheel can set vibrations in the engine and can badly damage the engine parts mainly the bearing and also increases the noise level of the engine. So a flywheel should essentially be checked for any imbalance in its configuration before mounting it up on the engine. The flywheel balancing machine detects the value of unbalance if any in any particular direction on the flywheel. The unbalance can be removed by drilling small holes in the flywheel. 2.2.2 OPERATING INSTRUCTION :- 1. Check the machine for its settings. 2. Load the flywheel without ring gear on work fixture of machine. 3. Clamp the job and ensure proper tightening. 4. Start the machine and check the amount and position of imbalance in degree of flywheel. 5. If unbalance is less than 5.4 gms for Dual Clutch (DC) and less than 4.2 gms for Single Clutch (SC), stop the machine and accept the job. 6. If unbalance is greater than 5.4 gms for DC and greater then 4.2 gms for SC stop the machine. Take the job to the graduated scale work showing unbalance (in degrees). 7. Remove the material by drilling hole of diameter 0.08 mm and up to a maximum drill depth of 40 mm. 8. Material extracted is 3.85 gms/cm of full depth. 9. Now check for unbalance again. 10. If unbalance is within specified limits accept the job. 11. Repeat the sequence for further jobs. 12. Calibration is scheduled every month. The hydraulic press is used for press fitting components like hubs, boss, gears onto shafts and so forth. Electric Ovens are provided for heating and shrink fitting of components like ring gear onto flywheel, timing gear onto crank shaft.In addition to these, a gravity roller conveyor system is used in this shop and throughout the plant for conveying the heavy components, finished and semi- finished assemblies from one place to another. Over head cranes are also installed in this shop to assist the locomotion work and lifting heavy loads. The shop is connected to the store where tested components are stored in and brought to the engine assembly shop frequently as and whenever required. 2.2.3 COMPONENTS OF ENGINE :- Cylinder Block and Crankcase: The basic framework of the engine is formed by the cylinder block. It houses the liners, which serves as bearings and guides for the piston reciprocating in them. Around the cylinders, there are passages for circulation of coolant. Cylinder block also carries lubrication oil to various components through drilled passages called oil galleries.During manufacture, the oil holes are drilled and rarely cast. Incase of curved passage, intersecting drilled holes are used. The ends of the drilled holes are sealed by plugs. At the lower end, crankcase is cast integral with the block. The function of the crankcase is to provide support for the main journals and bearings of the crankshaft, rigidly maintaining the alignment of their axes of rotation under various engine loads. Cylinder head: It is attached to the top of the cylinder block, called block deck, by means of studs fixed to the block. The gaskets are used to provide a tight leak proof joint at the interface of the head and the block. The cylinder head forms a combustion chamber above each cylinder. It also contains valve guides, valve seats, and ports, cooling water jackets and threaded holes for spark plugs or injectors. Heads are cast from cast iron or aluminum alloy. They are machined to take the various parts that are attached to or installed in the head. Oil pan or sump: Oil pan or sump forms the bottom half of the crankcase. It is attached to the crankcase through set screws and with a gasket to make the joint leak proof. Its functions are: 1. To store the oil for the engine lubricating system. 2. To collect the return oil draining from the main bearings or from the crankcase walls. 3. To serve as a container in which any impurities or foreign matter, e.g., liquid fuel, condensed water, sludge, metal particles etc. can settle down. 4. To enable the hot churned up lubricating oil to settle for a while before being circulated. 5. To provide for cooling of the hot oil in the sump by transfer of heat to the outsider air stream. The sump has shallow downward slope at the one end which merges with deep, narrow reservoir at the other end. This is done to ensure that under all conditions of vehicle running, there will be oil in the reservoir where oil pump is mounted slightly, slipped over the head of the piston, and into ring grooves cut in the piston. Manifolds: There are separate sets of pipes attached to the cylinder head which carry the air fuel mixture and the exhaust gases. These are called manifolds. The intake manifold is a set of tubes which carry air or air-fuel mixture from the throttle valves to the intake ports in the cylinder head. On in-line engines, the intake manifold attaches to the side of the cylinder head. The exhaust manifold is again a set of tubes which carries the exhaust gas from the cylinder head to the exhaust system. The manifold attaches to the head so the exhaust ports in the head align with the tube openings. An inline engine needs one exhaust manifold. The manifolds are made out of casting having smooth interior surface and rounded bends to offer minimum resistance to the flow of air or exhaust gases. Cylinder liners: The problem of cylinder wear in the engines is very acute one especially when cylinder block is made from aluminum alloy. The solution to this has been found in the use of cylinder liners, which can be replaced when these are worn out. Liners are also used to restore to its original size a cylinder block which has been rebored beyond allowable limits. They are made in the form of barrels from special alloy iron containing silicon, manganese, nickel and chromium. These are cast centrifugally. The liner may be further hardened by nitriding or chromium plating. The cylinder liners are of 2 types: The dry liners. The wet liners. • The dry liners: This type of liner is made in the shape of a barrel with flange at the top which keeps it into position. The entire outer surface bears against the cylinder block casting and hence has to be machined very accurately both from the inside and the outside. It is put in position by shrinking the liner. This introduces some stresses due to shrinkage and hence the liner bore has to be machined accurately again after the liner has been put into the cylinder casting.Too loose a liner will result in poor heat dissipation because of absence of a good contact with the cylinder block. This will result in the higher operating temperature. If the lubrication is also deficient, it may cause scuffing. Too tight a liner is even worse then the too loose case as it produces distortion of cylinder block, liner cracking, hot spots and scuffing. • The wet liner: This type of liner remains in direct contact with the cooling water on the outside and hence the entire outer surface does not require very accurate machining, but water tight joint have to be provided. At the top, the liner is provided with a flange which fits into the groove in the cylinder block. At the bottom either the block or the liner is provided with grooves, generally 3 in number. The middle groove is left empty and in the top and bottom ones are inserted packing rings made of synthetic rubber. Wet liners are sometimes coated with aluminum from outside, which makes them corrosion resistant. Piston and piston rings: Pistons are made of aluminum alloys. They weigh about 1 pound (0.454 kg). The piston is slightly smaller than the cylinder, which allows the piston to slide up and down. This is a sliding fit. Because the pistons are slightly smaller, there is a small gap or piston clearance between the piston and the cylinder wall. This gap must be closed otherwise, some of the compressed air-fuel mixture or air will leak past the pistons into the crankcase. This leakage is blowby. Excessive blowby reduces engine power, wastes fuel, and pollutes the air. To prevent excessive blowby, piston rings are installed on the pistons. The rings are split at one point. This allows them to be expanded slightly, slipped over the head of the piston, and into ring grooves cut in the piston. There are 2 types of piston rings: • Compression rings: These form a sliding seal between the piston and the cylinder wall. • Oil-control rings (or oil rings): These scrape off most of the lubricating oil splashed on the cylinder wall, and return the oil to the crankcase. Number of rings: The number of rings used on a piston varies depending upon requirement. With the modern trend of decreased engine heights, the number of rings is restricted to 3, out of which one is the oil control ring. A minimum of two of 2 compression rings are required because of the high pressure difference between the combustion chamber and the crankcase at the beginning of the power stroke. This difference may be as high as 70 atmospheres. A single piston ring cannot take such high pressure, which necessitates the use of at least 2 compression rings, which divide the pressure between themselves. Increasing the number of rings also reduces the design pressure between the rings and the cylinder walls which results in decreased wear and consequently increased life. Construction features and material: The top of the piston is called head or crown. Generally, low cost, low performance engines have flat heads. In some pistons which come quite close to the valves, the head is provided with valve relief. Pistons used in some high powered engines may have raised dome, which is used to increase the compression ratio as well as to control the combustion. Incase of piston containing part of combustion chamber in its crown, compression ratio can be controlled very accurately, but the disadvantage is that in this case much larger amount of heat has to be dissipated through the piston and the rings.Towards the top of the piston of a few grooves are cut to house the piston rings. The bands between the grooves are known as “lands”. These lands support the ring against the gas pressure and guide them so that they may flux freely in the radial direction. The part of the piston below the rings is called “skirt”. Its function is to form a guide suitable for absorbing side-thrust due to gas pressure. This side thrust is produced on account of the inclination of the connecting rod with the cylinder axis. The distance between the axis of the piston pin and the top of the piston crown is called “compression height” and determines the compression ratio for a given engine. Thus for the same engine, a piston with lesser compression height would give lesser compression ratio and vice versa. Crankshaft and flywheel: Crankshaft is the engine component from which the power is taken. It receives the power from the connecting rods in the designated sequence for onwards transmission to the clutch and subsequently to the wheels. The crankshaft is a one-piece casting or forging of heat-treated alloy steel. Counter-weights placed opposite the crankpins balance the crankshaft. The distance between the axis of the main journal and the crankpin centre line is exactly one half of the engine stroke and is called the “crank-throw”, which determines the crankshaft turning effort. Oil holes are drilled from main journal to the crankpins through crank webs to provide lubrication of big end bearings. Main bearings are lubricated from oil galleries in the cylinder block.On one of the main bearing journals usually near the flywheel end, thrust bearing is located so as to support the loads in the direction of the shaft axis. Such loads may arise due to clutch release forces, forces in the helical gear valve-timing gear train when accelerating or deceleration, forces in the gear train when driving various auxiliary components, e.g., the oil pump, water pump, supercharger, etc. or forces in the helical gear drive on front wheel driven cars. On the front of the crankshaft are mounted: (i) Timing gear or sprocket which drives the camshaft. (ii) Vibration damper. (iii) Pulley for driving the water pump, fan and the generator. On the rear end is mounted the flywheel, which serves as the energy reservoir. The flywheel also has ring gear mounted on its periphery having teeth which mesh with the pinion of the starting drive to start the engine. The flywheel also provides the frictional drive surface for the clutch-type mechanical drive. Besides, the timing marks are also usually located on the flywheel. These marks indicate the TDC piston position in degrees for cylinder no.1 and are used to determine ignition or injection timing. Flywheels are made from cast iron alloys or cast or rolled steel. Vibration dampers: The power stroke tends to twist the crankshaft. Each power stroke applies a force that may exceed 4000 pounds (18000 N) on the crankpin. This force tries to push the crankpin ahead of the rest of the crankshaft. Then, as the force on the crankshaft recedes, the crankshaft untwists. The twist-untwist action repeats with every power stroke. The action tends to create an oscillating motion in the crankshaft. This torsional vibration tends to break the crankshaft. A vibration damper (or harmonic balancer) helps control torsional vibration. The damper mounts on the front end of the crankshaft. This forms the hub to which the crankshaft pulley attaches the inertia ring is bonded through the rubber ring to the pulley. The inertia ring has a damping effect which tends to hold the crankshaft at a constant speed. This cancels the twist-untwist action. Connecting rod: The connecting rod connects the piston pin to the crankpin and converts the reciprocating motion of the piston into the rotary motion of the crankshaft. To reduce the obliquity of the rod with the cylinder axis, its length should be kept as large as possible. Reduced obliquity decreases the oscillating angular motion of the rod about its small end, thereby decreasing the piston side-thrust and improving the reciprocating balance of the engine. A combination of axial and bending stresses act on the rod in operation. The axial stresses are produced due to cylinder gas pressure (compressive only) and the inertia force arising on account of the reciprocating motion (both tensile as well compressive), whereas bending stresses are caused due to centrifugal effects. To provide the maximum rigidity with minimum weight, the main cross-section of the connecting rod is made I-section. This I-section is made to blend smoothly into the 2 rods-ends, called the small end and the big end. The small end of the rod has either a “solid” eye or a “split eye”, this end holding the piston pin. The big end works on the crank pin and is always split. In some connecting rods, a hole is drilled between 2 ends for carrying lubricating oil from the big end to the small end for lubrication of the piston pin and the piston. The connecting rods are generally made by drop forging of steel or duralium. Forged connecting rods are compact and lighter which is an advantage from inertia view point, whereas cast connecting rods are comparatively cheaper, but on account of lesser strength their use is limited to small and medium size petrol engines. Piston pin:- Piston pin or wrist pin or gudgeon pin connects the piston and the connecting rod. For lightness it is made in tubular form. It passes through the bosses in the piston and the small end of the connecting rod. It is made of low carbon case hardened steel having 0.15% carbon, 0.3% silicon, 0.5% manganese and the remainder iron. The pin is carburized, hardened by quenching and finally tempered. The piston pins are usually lapped to a very fine surface finish of about 0.1 micrometer, without which it is likely to fail very early due to fatigue caused by surface irregularities. Engine bearings: Bearings are placed in the engine where there is rotary motion between engine parts. These bearings are usually sleeve bearings that fit like sleeves around the rotating shafts. The part of the shaft that rotates in the bearing is a journal. Crankshaft and connecting-rod bearings are split into 2 parts. One half of the connecting-rod bearing fits into the connecting rod. The other half fits into the rod-bearing cap. One half of the crankshaft or main bearings fit into a semicircle machined in the cylinder block. The other half fits into the main-bearing cap. A thrust bearing limits crankshaft endplay. The thrust bearing is one of the main bearings that have flanges on its 2 sides. Flanges on the crankshaft fit close to the thrust-bearing flanges. This limits the forward and rearward movement of the crankshaft. The engine oil pump sends oil onto the bearing surfaces. The rotating crankshaft journals are supported on layers of oil. The difference between the journal diameter and the bearing diameter is the oil clearance which remains filled with oil layer in a running engine. Valve and valve trains: Each engine cylinder has at least 2 valves: an intake valve and exhaust valve. The valves are operated by a valve train. There are 2 basic types of valve trains. These are overhead camshaft with bucket tappets or rocker arms, and camshaft in block with pushrods. • Driving the camshaft: The camshaft in the block is driven either by timing gears or by sprockets and timing chain. The reason the gears are timing gears and the chains or belts are timing chains or timing belts is that they “time” the opening and closing of valves. • Camshaft timing: Camshaft timing is the relationship between the camshaft and crankshaft. The camshaft is driven by the crankshaft. Anything that affects this relationship may greatly affect engine operation. There are 4 strokes to the complete cycle of actions in the 4-stroke-cycle engine. The crankshaft must turn 2 times to turn the camshaft once, which opens each valve once. This 1:2 gear ratio is achieved by making the camshaft gear or sprocket twice as large as the crankshaft gear or sprocket. • Valve cooling: The intake valve runs relatively cool. It passes only the air-fuel mixture. But the exhaust valve passes the very hot exhaust gases. The exhaust valve may become red hot in operation, with temperatures of up to 1600°F (871°C). The valve seat and stem are cooled by the engine cooling system. Coolant circulates through the water jackets or coolant passages around the valve seat and valve guide in the cylinder head. • Rocker arm: A rocker arm is a pivot lever that transfers cam or pushrod motion to the valve stem. Many rocker arms are made of stamped steel and others are forges or cast aluminum.The pivot point of a rocker arm is usually offset from the center. This provides a rocker-arm ratio of about 1.5:1. In an upward pushrod movement of 0.250 inch (6.35 mm) forces the valve stem down 1.5 times that distance. This is 0.375 inch (9.5 mm). Because of rocker-arm ratio, the cam lobe can be smaller. However, this places a greater load on the pushrod, valve lifter, and cam lobe. • Valve lifters (tappets): In pushrod engines, the valve lifter or tappet is the part that transmits cam-lobe movement to the pushrod. The cam lobe raises the tappet which raises the pushrod. The pushrod causes the rocker arm to rock. This pushes the valve down, off its seat. Gaskets: Gaskets are used to provide a tight fitting joint be