BASIC TRAINING CENTER

Lalgarh, Bikaner

30 Day Practical Training Report20th may to 19th June 2009

Submitted By:Ankit Joshi

B.Tech. 3rdyear, M.E.Gyan Vihar School of Engineering &

Technology

Submitted To:

Mr. Ananjay Mishra Mr. Gopal SharmaAsstt. Prod. Eng Sr. Instructor, B.T.C.

N.W. Railway, Workshop, N.W. Railway, Workshop,Lalgarh, Bikaner Lalgarh, Bikaner

Gyan Vihar School of Engineering & Technology

Practical Training Report-2009At Railway work shop Bikaner

ACKNOWEDGEMENT

I am very thankful to all section Engineers, Forman, machine operators and my Shri Gopal Sharma S.E. who is guided me all through my practical training period at this prestigious work shop of North Western Railway, Lalgarh, Bikaner.

Indian RailwaysIndian Railways

TypeDepartmental Undertaking of The Ministry of Railways, Government of India

Founded 26 April 1853

Headquarters New Delhi, India

Area served India

Key people

Union Railway Minister:Mamata BanerjeeMinisters of State for Railways :E. Ahamed and K.H. MuniyappaChairman, Railway Board:S.S. Khurana.[1]

Industry Railways and Locomotives

Services Rail transport

Revenue▲ Rs. 107.66 billion (US$19.13 billion)[2]

Employees 1,406,430 (2007)[3]

ParentMinistry of Railways, Government of India

Divisions16 Railway Zones (excluding Konkan Railway)

Website www.indianrailways.gov.in

Indian Railways (Hindi: भारतीय रेल Bhāratīya Rail), abbreviated as IR (भारे), is the state-owned railway company of India, which owns and operates most of the country's rail transport. It is overseen by the Ministry of Railways of the Government of India.

Indian Railways has one of the largest and busiest rail networks in the world, transporting over 18 million passengers and more than 2 million tonnes of freight daily. It is the world's largest commercial or utility employer, with

more than 1.4 million employees. The railways traverse the length and breadth of the country, covering 6,909 stations over a total route length of more than 63,327 kilometres (39,350 mi). As to rolling stock, IR owns over 200,000 (freight) wagons, 50,000 coaches and 8,000 locomotives.

Railways were first introduced to India in 1853. By 1947, the year of India's independence, there were forty-two rail systems. In 1951 the systems were nationalised as one unit, becoming one of the largest networks in the world. IR operates both long distance and suburban rail systems on a multi-gauge network of broad, metre and narrow gauges. It also owns locomotive and coach production facilities.

History

A plan for a rail system in India was first put forward in 1832, but no further steps were taken for more than a decade. In 1844, the Governor-General of India Lord Hardinge allowed private entrepreneurs to set up a rail system in India. The East India Company (and later the British Government) encouraged new railway companies backed by private investors under a scheme that would provide land and guarantee an annual return of up to five percent during the initial years of operation. The companies were to build and operate the lines under a 99 year lease, with the government having the option to buy them earlier.

Extent of Great Indian Peninsular Railway network in 1870. The GIPR was one of the largest rail companies at that time.

Map of the Madras and South Mahratta Railway lines

Two new railway companies, Great Indian Peninsular Railway (GIPR) and East Indian Railway (EIR), were created in 1853-54 to construct and operate two 'experimental' lines near Bombay and Calcutta respectively. The first train in India had become operational on 22 December 1851 for localised hauling of canal construction material in Roorkee. A year and a half later, on 16 April 1853, the first passenger train service was inaugurated between Bori Bunder in Bombay and Thane. Covering a distance of 34 kilometres (21 mi), it was hauled by three locomotives, Sahib, Sindh, and Sultan.

In 1854 Lord Dalhousie, the then Governor-General of India, formulated a plan to construct a network of trunk lines connecting the principal regions of India. Encouraged by the government guarantees, investment flowed in and a series of new rail companies were established, leading to rapid expansion of the rail system in India. Soon various native states built their own rail systems and the network spread to the regions that became the modern-day states of Assam, Rajasthan and Andhra Pradesh. The route mileage of this network increased from 1,349 kilometers (838 mi) in 1860 to 25,495 kilometres (15,842 mi) in 1880 - mostly radiating inland from the three major port cities of Bombay, Madras, and Calcutta. Most of the railway construction was done by Indian companies. The railway line from Lahore to Delhi was done B.S.D. Bedi and Sons (Baba Shib Dayal Bedi), this included the building of the Jamuna Bridge. By 1895, India had started building its own locomotives, and in 1896 sent engineers and locomotives to help build the Uganda Railway.

At the beginning of the twentieth century India had a multitude of rail services with diverse ownership and management, operating on broad, metre and narrow gauge networks.In 1900 the government took over the GIPR network, while the company continued to manage it. With the arrival of the First World War, the railways were used to transport troops and foodgrains to the port city of Bombay and Karachi en route to UK, Mesopotamia, East Africa etc. By the end of the First World War, the railways had suffered immensely and were in a poor state. In 1923, both GIPR and EIR were nationalized with the state assuming both ownership and management control.

The Second World War severely crippled the railways as rolling stock was diverted to the Middle East, and the railway workshops were converted into munitions workshops. At the time of independence in 1947, about 40 per

cent of the railways then went to newly-created nation of Pakistan.A total of forty-two separate railway systems, including thirty-two lines owned by the former Indian princely states, were amalgamated as a single unit which was christened as the Indian Railways. The existing rail networks were abandoned in favour of zones in 1951 and a total of six zones came into being in 1952.

As the economy of India improved, almost all railway production units were 'indigenised' (produced in India). By 1985, steam locomotives were phased out in favour of diesel and electric locomotives. The entire railway reservation system was streamlined with computerisation between 1987 and 1995.

Organisational structure

A schematic map of the Indian Railways network, showing the various zones.

Indian Railways is a department owned and controlled by the Government of India, via the Ministry of Railways rather than a private company. As of May 2009 , the Railway Ministry is headed by Mamata Banerjee, the Union Minister for Railways and assisted by two ministers of State for Railways. Indian Railways is administered by the Railway Board, which has six members and a chairman.

Railway zones

The headquarters of the Indian Railways in New Delhi

Indian Railways is divided into zones, which are further sub-divided into divisions. The number of zones in Indian Railways increased from six to eight in 1951, nine in 1952, and finally 16 in 2003. Each zonal railway is made up of a certain number of divisions, each having a divisional headquarters. There are a total of sixty-seven divisions.

The Kolkata Metro is owned and operated by Indian Railways, but is not a part of any of the zones. It is administratively considered to have the status of a zonal railway.

Each of the sixteen zones, as well as the Kolkata Metro, is headed by a General Manager (GM) who reports directly to the Railway Board. The zones are further divided into divisions under the control of Divisional Railway Managers (DRM). The divisional officers of engineering, mechanical, electrical, signal & telecommunication, accounts, personnel, operating, commercial and safety branches report to the respective Divisional Manager and are in charge of operation and maintenance of assets. Further down the hierarchy tree are the Station Masters who control individual stations and the train movement through the track territory under their stations' administration.

Sl. No   Name   Abbr.   Date

Established   Headquarters   Divisions  

1. Central CR November 5, 1951 Mumbai

Mumbai, Bhusawal, Pune, Solapur, Nagpur

2. East Central ECR October 1,

2002 HajipurDanapur, Dhanbad, Mughalsarai, Samastipur, Sonpur

3. East Coast ECoR April 1, 2003 Bhubaneswar

Khurda Road, Sambalpur, Visakhapatnam

4. Eastern ER April, 1952 Kolkata Howrah, Sealdah, Asansol, Malda

5. North Central NCR April 1, 2003 Allahabad Allahabad, Agra,

Jhansi

6. North Eastern NER 1952 Gorakhpur Izzatnagar,

Lucknow, Varanasi

7. North Western NWR October 1,

2002 Jaipur Jaipur, Ajmer, Bikaner, Jodhpur

8. Northeast Frontier NFR 1958 Guwahati

Alipurduar, Katihar, Lumding, Rangia, Tinsukia

9. Northern NR April 14, 1952 Delhi Delhi, Ambala,

Firozpur, Lucknow, Moradabad

10. South Central SCR October 2,

1966 Secunderabad

Secunderabad, Hyderabad, Guntakal, Guntur, Nanded, Vijayawada

11.South East Central

SECR April 1, 2003 Bilaspur, CG Bilaspur, Raipur, Nagpur

12. South Eastern SER 1955 Kolkata

Adra, Chakradharpur, Kharagpur, Ranchi

13. South Western SWR April 1, 2003 Hubli Hubli, Bengaluru,

Mysuru

14. Southern SR April 14, 1951 Chennai

Chennai, Madurai, Palakkad, Salem, Tiruchchirapalli, Thiruvanathapuram

15. West Central WCR April 1, 2003 Jabalpur Jabalpur, Bhopal,

Kota

16. Western WR November 5, 1951 Mumbai

Mumbai Central, Vadodara, Ratlam, Ahmedabad, Rajkot, Bhavnagar

Railway Production Units

A WAP5 locomotive

A diesel locomotive of Indian Railways powering Express train, that runs in Assam

The Indian Railways manufactures a lot of its rolling stock and heavy engineering components. As with most developing economies, the main reason is import substitution of expensive technology related products. This was relevant when the general state of the national engineering industry was immature.

The six manufacturing plants of the Indian Railways, called Production Units, are managed directly by the ministry. These six production units (PUs) are each headed by a General Manager (GM), who also reports directly to the Railway Board. The Production Units are:

Chittaranjan Locomotive Works, Chittaranjan Diesel Locomotive Works, Varanasi Diesel-Loco Modernisation Works, Patiala Integral Coach Factory, Chennai Rail Coach Factory, Kapurthala Rail Wheel Factory, Bangalore Rail Spring Karkhana, Gwalior

Other independent units of Indian Railways are:

Central Organization For Railway Electrification, Allahabad Central Organization For Modernization of Workshops, New Delhi

Research Design and Standards Organization (RDSO), Lucknow is the R&D division of Indian Railways and functions as the technical advisor to Railway Board, Zonal Railways, and Production Units.

Bharat Earth Movers Limited (BEML), Bangalore is an organization unrelated to the Indian Railways, however it manufactures coaches for both the Indian Railways and the Delhi Metro system.

The Central Organisation for Railway Electrification (CORE), Metro Railway, Calcutta and construction organisation of NFR are also headed by a General Manager.

Railway PSU's

Apart from these zones and production units, a number of Public Sector Undertakings are under the administrative control of the ministry of railways. These units are:

1. Dedicated Freight Corridor Corporation of India 2. Indian Railways Catering and Tourism Corporation 3. Konkan Railway Corporation 4. Indian Railway Finance Corporation 5. Mumbai Rail Vikas Corporation 6. Railtel Corporation of India – Telecommunication Networks 7. RITES Ltd.  – Consulting Division of Indian Railways 8. IRCON International Ltd.  – Construction Division 9. Rail Vikas Nigam Limited 10. Container Corporation of India 11. Rail Land Development Authority is a statutory authority formed

through an amendment of the Railways' Act, 1989 for commercial development of vacant railway land/

12. Centre for Railway Information Systems is an autonomous organisation under the Railway Board, which is responsible for developing the major software required by Indian Railways.

The Delhi Metro railway

Passenger services

A DMU Train

Indian Railways operates about 9,000 passenger trains and transports 18 million passengers daily across twenty-eight states and one union territory, Puducherry (formerly Pondicherry). Sikkim, Arunachal Pradesh, and Meghalaya are the only states not connected by rail. The passenger division is the most preferred form of long distance transport in most of the country. A standard passenger train consists of eighteen coaches, but some popular trains can have up to 24 coaches. Coaches are designed to accommodate anywhere from 18 to 81 passengers, but during the holiday seasons or when on busy routes, more passengers may travel in a coach. Most regular trains have coaches connected through vestibules. However, 'unreserved coaches' are not connected with the rest of the train via any vestibule.

Reservation against cancellation service is a provision for shared berth in case the travel ticket is not confirmed. It is a way of maximizing the number of wait-listed passengers to be accommodated in case of a cancellation.

Suburban rail

The Delhi Metro railway

Mumbai's suburban trains handle 6.3 million commuters daily.

Many cities have their own dedicated suburban networks to cater to commuters. Currently, suburban networks operate in Mumbai, Chennai, Kolkata , Delhi, Hyderabad, Pune and Lucknow. Hyderabad, Pune and Lucknow do not have dedicated suburban tracks but share the tracks with long distance trains. New Delhi, Kolkata, and Chennai have their own metro networks, namely the New Delhi Metro, the Kolkata Metro,and the Chennai MRTS, with dedicated tracks mostly laid on a flyover.

Suburban trains that handle commuter traffic are mostly electric multiple units. They usually have nine coaches or sometimes twelve to handle rush hour traffic. One unit of an EMU train consists of one power car and two general coaches. Thus a nine coach EMU is made up of three units having one power car at each end and one at the middle. The rakes in Mumbai run on direct current, while those elsewhere use alternating current.[18] A standard coach is designed to accommodate 96 seated passengers, but the actual number of passengers can easily double or triple with standees during rush hour.

Notable trains and achievements

A train on the Darjeeling Himalayan Railway

There are two UNESCO World Heritage Sites on IR — the Chatrapati Shivaji Terminus and the Mountain railways of India. The latter is not contiguous, but actually consists of three separate railway lines located in different parts of India:

The Darjeeling Himalayan Railway, a narrow gauge railway in West Bengal.

The Nilgiri Mountain Railway, a metre gauge railway in the Nilgiri Hills in Tamil Nadu.

The Kalka-Shimla Railway, a narrow gauge railway in the Shivalik mountains in Himachal Pradesh.

The Palace on Wheels is a specially designed train, frequently hauled by a steam locomotive, for promoting tourism in Rajasthan. On the same lines, the Maharashtra government introduced the Deccan Odyssey covering various tourist destinations in Maharashtra and Goa, and was followed by the Government of Karnataka which introduced the Golden Chariot train connecting popular tourist destinations in Karnataka and Goa. However, neither of them has been able to enjoy the popular success of the Palace on Wheels.

The Samjhauta Express is a train that runs between India and Pakistan. However, hostilities between the two nations in 2001 saw the line being closed. It was reopened when the hostilities subsided in 2004. Another train connecting Khokhrapar (Pakistan) and Munabao (India) is the Thar Express that restarted operations on February 18, 2006; it was earlier closed down after the 1965 Indo-Pak war. The Kalka Shimla Railway till recently featured in the Guinness Book of World Records for offering the steepest rise in altitude in the space of 96 kilometres.

A Beyer Garratt 6594 Engine seen at the National Rail Museum

The Lifeline Express is a special train popularly known as the "Hospital-on-Wheels" which provides healthcare to the rural areas. This train has a carriage that serves as an operating room, a second one which serves as a storeroom and an additional two that serve as a patient ward. The train travels around the country, staying at a location for about two months before moving elsewhere.

Among the famous locomotives, the Fairy Queen is the oldest running locomotive on the mainline (though only for specials) in the world today, though the distinction of the oldest surviving locomotive that has recently seen service belongs to John Bull. Kharagpur railway station also has the distinction of being the world's longest railway platform at 1072 m (3,517 ft). The Ghum station along the Darjeeling Toy Train route is the second highest railway station in the world to be reached by a steam locomotive.[22] The Mumbai–Pune Deccan Queen has the oldest running dining car in IR.

The Himsagar Express, between Kanyakumari and Jammu Tawi, has the longest run in terms of distance and time on Indian Railways network. It covers 3,745 km (2,327 miles) in about 74 hours and 55 minutes. The Bhopal Shatabdi Express is the fastest train in India today having a maximum speed of 150 km/h (93.7 mph) on the Faridabad–Agra section. The fastest speed attained by any train is 184 km/h (114 mph) in 2000 during test runs.

The Rajdhani Express and Shatabdi Express are the superfast, fully air-conditioned trains that give the unique opportunity of experiencing Indian Railways at its best.

Freight

A single line rail bridge

IR carries a huge variety of goods ranging from mineral ores, fertilizers and petrochemicals, agricultural produce, iron & steel, multimodal traffic and others. Ports and major urban areas have their own dedicated freight lines and yards. Many important freight stops have dedicated platforms and independent lines.

Indian Railways makes 70% of its revenues and most of its profits from the freight sector, and uses these profits to cross-subsidise the loss-making passenger sector. However, competition from trucks which offer cheaper rates has seen a decrease in freight traffic in recent years. Since the 1990s, Indian Railways has switched from small consignments to larger container movement which has helped speed up its operations. Most of its freight earnings come from such rakes carrying bulk goods such as coal, cement, food grains and iron ore.

Indian Railways also transports vehicles over long distances. Trucks that carry goods to a particular location are hauled back by trains saving the trucking company on unnecessary fuel expenses. Refrigerated vans are also available in many areas. The "Green Van" is a special type used to transport fresh food and vegetables. Recently Indian Railways introduced the special 'Container Rajdhani' or CONRAJ, for high priority freight. The highest speed notched up for a freight train is 100 kilometres per hour (62 mph) for a 4,700 metric tonne load.

Recent changes have sought to boost the earnings from freight. A privatization scheme was introduced recently to improve the performance of freight trains. Companies are being allowed to run their own container trains. The first length of an 11,000-kilometre (6,800 mi) freight corridor linking India's biggest cities has recently been approved. The railways has increased load limits for the system's 225,000 freight wagons by 11%, legalizing something that was already happening. Due to increase in manufacturing transport in India that was augmented by the increase in fuel cost, transportation by rail became advantageous financially. New measures such as speeding up the turnaround times have added some 24% to freight revenues.

CHRONICAL HISTORY

Train operations in this Western part of Rajasthan in the erstwhile Bikaner state were initially under’ Jodhpur and Bikaner State Railways’. Later when Maharaja Ganga Singh Ji Bahadur took over the reins of Bikaner state.The train operations of Bikaner state came under his patronage under the banner of ‘Bikaner State railways’. At that time there was no agreement for over-hauling of Loco coaches. Wagon and other allied stock. Foundation stone for this workshop was laid by “Maharaja Ganga Singh Ji Bahadur” on 18th March 1925 in the outskirts of Bikaner town known as Lalgarh. Over the years, the mushrooming growth of colonies in the around Bikaner and Lalgrah has resulted in amalgamation of the township with Bikaner.

The other motive to setup for this workshop was to provide employment opportunities to local inhabitants.

The functioning on 1st march 1921 i.e. within one year of its inception. This workshop remained under state Govt. up to 1.4.1949 and there after under Central Govt. up to 1.4.1950. With the recognition of Railways network, the workshop becomes a part of northern Railways W.e.f.14.4.1952.

The workshop was entrusted with qualitative and quantitative targets for maintenance of M.G. Rolling stock along with manufacture of components required for its own use and also for the division.

ACTIVITIES

The workshop was initially set up as M.G.POH Shop for Locos, Coaches and Wagons and within a short span became a premier source of repairs and manufacture of Loco, Carriage and Wagon Wheels and Components for its own use and for the division with the advent of modern technology, where diesel traction was phased out form this region Also last steam Loco 3504 YG rolled out of this workshop on 31.3.94 after IOH. The staff rendered surplus due to phasing out of steam traction has been re-deployed on the new activities.

With conversion of Jodhpur shops from M.G. to B.G.POH of air Conditioned M.G. Coaches was transferred to this work shop in 1996 and POH of non AC MC Coaches of Jodhpur division has been transferred w.e.f. July 1998.

WORK SHOP AT A GALANCE

Total Area - 141226 sq.m.Total covered area - 24292 sq. m.Track inside workshop - 2.6kms.Roads - 6760Machinery & Plants - 232Manpower - 1405Staff quarters - 340Over Head Cranes - 03 (25 m.t. 05 m.t.) under Area crane 25 m.t. - 3972 sq.m. 05 m.t. - 2905 sq.m.

Hoists/Cranes - 27Connected Load - 3300 k.w. Maximum Demand - 480 kva Contract Demand - 500 kvaTransformer capacity -1450 kvaDiesel Generating - 3 (500kva, 300kva, 125kva)Average Power Factor - 0.9

PERIODIC OVER HAULING

Periodic over hauling (P.O.H.) is a process of 18 days during which checking and repair / replacing of parts take place. Time period of POH for:

Mail Exp POH after 12 monthPassenger POH after 18 month

Procedure of POH:-

01 day Disassemble of electrical components (Carriage shop)

02 day lift, lowering and stripping. (Carriage shop)

03 day Body repair. (Welding and carpenter shop)

04 day Carpenter work. (Carpenter shop)

05 day Painting. (Painting shop)

01 day Electrical component fitting (Carriage Shop)

01 day Adjustment of all parts (Carriage shop) 01 day Vacuum testing. (Vacuum shop)

MACHINE SHOP

HEGENSCHEIDT MACHINE

Hegenscheidt wheel set lathe type 1672 is suitable for Machining the profile of newly tired or worn wheel set in locomotive and rail passengers & freight cars.

PARTS OF HEGENSCHEIDT MACHINE

1. Left hand head stock 2. Right hand head stock 3. Hegomatic tool post (left hand) 4. Hegomatic tool post (Right hand) 5. Operator’s station 6. Face plat 7. Center barrel with center 8. Axial grip driver 9. Wheel set lifting device 10. Wheel set centering device 11. Lateral tool holder 12. Double turning tool 13. Topping tool 14. Lateral positioning device 15. Lateral correcting device 16. Setting knob for profile templates 17. Copy fracer 18. Tecoplate slide 19. Feed pump 20. Feed rate setting knob 21. Optical diameter measuring arrangement 22. Driver for left hand head stock motion 23. Lubricating elements for right hand head stock and hegomatic copy tool post 24. Lubricating elements for left hand stock head

A hydraulic wheel set jack rises the wheel set into centering position where a wheel set self centering unit will taken over. In its centering position, the wheel set will be taken by lathe centers at both ends and clamped between four jaw drivers that can be centrally adjusted.

HEGENSCHEIDT WHEEL LATHE

The wheel set is driven via two planetary spur gear transmission having four manual shifts to obtain 12 faceplate speeds. The hegomatic copying slides of the machine will simultaneously start lathe work on both wheels in the set their motion being controlled by means of templates and hydraulic copying tracers.

The copying operation and subsequent retraction of the copying slide into their initial position is a faulty automatic process. The axial adjustment of the two-hegomatic copying slides relative to the mounted wheel set is effected by lateral positioning units. The radial position of two hegomatic copying slides relative to the mounted wheel set will be determined via the optical wear measuring system for the machining of the wheel set clamping type tools with reversible carbide tips will be used exclusively.

Excellent cutting efficiency and hence production capacity, machining accuracy and extended service life are ensured due to the purposeful structural configuration of the machine.

ROLLER AND BEARING SHOP

ROLLER BEARING

BEARING

A bearing is a component used to reduce friction in a machine. Bearings may be classified broadly according to the motions they allow and according to their principle of the operation.

Major types

Common motions include linear/axial and rotary/radial. A linear or thrust bearing Allows motion along a straight line, for example a drawer being pulled out and pushed in. A rotary bearing allows motion about a center, such as a wheel on a shaft or a shaft through housing. Common kinds of rotary motion include both one direction rotation and oscillation where the motion only goes through part of revolution. Essentially, bearings can reduce friction by shape, or by its material.

By shape, finds an advantage by reducing contact surface, such as using a sphere to roll anything on. By material, exploits the nature of the bearings material used. An example would typically be the various plastics that have self-lubricating properties.

Combinations of shape and properties can even employ with the same bearing. An example of this is where the cage is made of plastic, and it separates the roller/balls, which reduce friction by their shape and finish.

Principles of operation

There are at least six common principles of operation: sliding bearings, usually called “bushings”; “journal bearings”, sleeve bearings:, or plain bearings”; rolling-element bearings such as ball bearings and roller bearings; jewel bearings, in which the load is carried by rolling the axle slightly off-center; fluid bearings, in which the load is carried by a gas or liquid; magnetic bearings, in which the load is carried by a magnetic field; and flexure bearings, in which the motion is supported by a load element which bends. ADVANTAGES OF ROLLER BEARINGS:

1. Roller bearings being anti friction less efforts are requires in the comparison to frictional bearings.

2. Engine can haul heavier weight.3. The percentage of running hot is comparison to conventional bearing is

nil.4. Since there in no wear on the journals, so the life of axles is increased.’5. Due to very little lateral clearances in the roller bearings, the riding has

been comfortable. 6. Every round trip or fortnightly oiling is not to be done.7. Quick acceleration of and high speed is achieved.8. Rolling stock can be hauled at higher speeds.

A roller bearing

DISADVANTAGES OF ROLLER BEARINGS:-

1. Initial cost of roller bearings is very high.2. Its fitment on journal requires extra ordinary care and handling by

highly skilled and trained staff.3. It requires a highly dust proof room, as a very little dust particle will

fail the bearing.4. Since they are supplied in fully assembled conditioned, so complete

changing of bearing is necessary even if a part damaged.

TYPES OF ROLLER BEARING

The following three types of roller bearings are in use on wagons, coaches and engines:

1. Roller.2. Inner race.3. Outer race.4. Cage.

Cylindrical Roller Bearings

Cylindrical roller bearings are used on wagons, BEML coaches and engines. Spherical roller bearings are used on ICF coaches, some wagons and engines. Tapered roller bearings are only used on engines.

WHEEL SHOP

The wheels of new tyre undergo various operations and for this the wheel shop is further divided into the major six sections.

Axel pressing section: In this section axel and tyre (solid) made from Company are received in the work shop as separate piece. On the pressing machine they are pressed and tyre axel assembly is made. The machine used for axel pressing is hydraulic in this there are pistons which are operated through cam and cam is run with the help of motor.

These pistons create pressure due to which on jaw moves as the pressure increases. Through the movement of the jaw, the jaw applies pressure on the axel and tyre which are clumped there is a clearance between the tyre and axel is kept. The dia of the axel is kept large in thousands place of decimal and dia of the tyre is kept small.

Tyre section: The tyre used is solid but they have a limit. When their dia is reduced to 610mm, then they are rejected and are converted in to rim. Then on this, tyres made in company are brought to the work shop and machine and are mounded on the rim. These tyre are also used till there outer dia is 610mm after that they are declared comdum. After that they are removed and row tyres are mounted on it. Mounting of tyre is done is heating furnace.

Heating furnace: In this furnace the process of mounting is done, for this the machined Tyre (of required size) is heating in the open furnace. This furnace is kerosene operated means kerosene is burned fire heating. The internal dia of tyre is smaller and dia of the rim is large in thousand place of decimal. The axel and rim assembly is then inserted in the tyre and brought out. After that a ring in inserted and hammered in the slot cuts in the tyre so that at running the tyre may not run out. The clearance is kept so that the tyre and axel get fixed after cooling.

Axel testing section: After the type has been mounted on the rim the tyre and axel assemble is sent for testing to check if there is any defect. Defects may be in form of porosity, inclusions Cracks, Scratch etc, and due to the movement of type they get increased If any defeat is found in the assembly then they are rejected. The process used for testing the defect is called ultrasound testing.

Ultrasound testing: The machine used for this testing consists of a probe which is connects to the machine with the help of lead. The machine has graphed screen and other contr4olling switch for controlling the frequency etc. the machine words at 190-230 volts.Is done so that if the axel face is oval, then the priobe will not come in confect with the end face and the sound waves will not pass through the axel. The main defects are cracks, which are created at the wheel seat because the whole load is on the wheel and wheel is fitted at the wheel seat. For checking the

wheel seat angular probe is used which splits the sound waves at the required angle.Procedure: after the axel face has been greased. The probe is connected to the machine and the machine is switched on and probe is touched to the axel face. Before doing this the machine is setted at the required frequency and graphed screen is calibrated for the required length. Than the probe is touched at the face of the axel at different places. If there are any cracks, inclusions or holes the graph will proke on the screen. This shows the defect and the axel is rejected.

Zyglo testing:

1. Apply dry fluorescent liquid (FP-23) on the roller bearing spraying or immersing.2. Remove excess liquid.3. Remove excess by washing with the water.4. Dry up the roller bearing by passing hot air through blowers.5. Put the roller bearing in dry developer’s power (28-D).6. Inspect the roller bearings under ultra violet lamp. “Clean the roller bearing by washing with water and reuse is passed.

WELDING SHOP

Welding consists of the joining of two or more pieces of metal by the application of heat and sometimes of pressure.

The process can be defined according to:1. The method of joining.2. The surface to be weld.

Further, it can be differentiated as to whether it isa) By handb) By machine.

Also, whether isa) By fusion.b) By pressure.

Classification of Welding Processes:

The welding processes can be classified as under:1. Gas Welding.2. Arc Welding.3. Resistance Welding.4. Induction Welding.5. Thermal Welding.6. Forge.7. Brazing.8. Soldering.

The processes can be further be sub divided as:

A. Gas Welding:1. Oxy- Acetylene welding.2. Air - Acetylene welding.3. Oxy – Hydrogen Welding.4. Pressure – Gas Welding.

B. Arc Welding:1. Carbon electrode.2. Metal electrode.

C. Resistance Welding:1. Stop Welding.2. Seam Welding.3. Projection Welding.4. Flash Welding.

5. Upset Welding.6. Percussion Welding.

D. Induction Welding.E. Thermit Welding:

1. Pressure Thermit Welding. 2. Non-Pressure Thermit Welding.

F. Forge Welding:1. Hammer Welding.2. Die Welding.3. Roll Welding.

G. Brazing:1. Torch Brazing.2. Furnace Brazing.3. Induction Brazing.4. Resistance brazing.5. Dip Brazing.

The operations performed in the welding shops are:1. Electric Welding.2. Gas Welding.3. Gas Cutting.4. Profile Cutting.

ARC WELDINGArc welding refers to a group of welding processes that use a welding power supply to create an electric arc between an electrode and the base material to melt at the welding point. They can use either direct(DC) or alternating (AC) current, and consumable or non-consumable electrodes. The welding region is sometimes protected by some type of inert or semi-inert gas, known as a shielding gas, and/or filler material. The process of arc welding is widely used because of its law capital and running costs. This also makes it ideal for use in schools and in other public setting.

An arc welding

Equipment of arc welding

The various forms of arc welding are:

1. Electro slag welding2. Plasma arc welding.3. Fluxes-core arc welding.4. Shielded-metal arc welding.5. Gas-metal arc welding.6. Submerged-arc welding.7. Gas tungsten-arc welding.

TYPE OF GAS TORCH HEAD

The top torch is a welding torch and the bottom is a cutting torch

OXYGEN RICH BLOW TORCH FLAME:-

Oxygen Rich Butane Torch Flame

FUEL RICH BLOW TORCH FLAME:-

Fuel Rich Butane Torch Flame

Oxy-Acetylene Cutting

The oxy-acetylene cutting process is achieved by blowing away the molten material which by the combustion heat of acetylene gas and oxygen. Generally, only steel material is cut using this process and material of remarkable thickness can be cut. However, the thickness that can be cut is based on a user’s skill and the size of a torch used.

Torch for the Cutting Tip of the Torch

TOOL SHOP

Shaper Machine:-It is used principally to machine flat or plane surfaces in horizontal, vertical and angular planes. The cutting tool is mounted on the shaper head to the ram. The ram imparts a reciprocating motion to the tool, which operates over the shaper table. It is generally not used as production machine. Vertical cuts can be taken by feeding the tool with the shaper head slide. The shaper head can be set at an angle in order to take angular cuts. Shaping operation is best suited for machining complex configurations like keep internal slots and difficult contours. When tool comes into contact with the job, it digs into the job and, therefore the edges are generally not flat but slightly over curved. Due to its limited length of stroke, it is conveniently adapted to small job and best suited for surface composed of straight – line elements and for batch production. It can produce all types of surface finishes. It is also best suited for cutting keyways and splines on shafts. Principle parts of shaper are:-

(1) Ram(2) Shaper head(3) Column(4) Base(5) Cross-rail(6) Saddle and table(7) Shaper gibs

A shaper machine

Working of shaper

(1) Work table on the work seat in the vise for parallelism with the movement of ram.

(2) Squareness of vise jaws.(3) For vertical facing, the tool movement should be exactly

perpendicular to the table.(4) Proper setting of job parallelism.

Milling machine: - Milling machine the process of removing metal by feeding the work past a rotating multipoint cutter. In milling operation the rate of metal removal is rapid as the cutter rotates at a high speed and has many cutting edges. Milling machine is one of the most important machine tools in a tool room as nearly all the operations can be performed on it with high accuracy.

Milling machine augments the work of a lathe and can produce the plain and curved surfaces and also helical grooves etc. It is possible to have relative motion between work piece and cutter in any direction and thus mill surfaces having any orientation. In milling operation, the cutting edge of the cutter is kept continuously in contact with the material being cut. The cut picks up gradually only according to the design; the distinctive classification is as follows:

(1) Column and knee milling machine(2) Bed-type milling machine (3) Plano-type milling machine(4) Special purpose milling machine

Principal Parts:(1) Base (2) Column (3) Knee (4) Saddle(5) Table (6) Over arm (7) Spindle (8) Arbor

In workshop we have study about Ram type universal machine.

A milling machineRam type milling machine: - In place of ordinary type over-arm, there is ram which can slide forward and backward for the adjustment of tool position or for shifting the cutter position quickly. The cutter head is pivoted to the face of the arm and is capable of any angle adjustment between vertical and horizontal positions. This range of adjustment often makes it possible to complete jobs with one set up with out having to change the job to some other machine.

Thus the movable ram enables the throat distance to be adjusted in or out, bringing the spindle in each case as close to the column as is possible.

A ram type milling machine

Some of the most common operations which can be performed on milling machine are:

(1) All kinds of grooves; straight, spiral, vertical, and formed.(2) Splines and key ways on shafts.(3) Slots for inserting teeth in milling cutters.(4) Flats surfaces of all kinds at any angle.(5) Contours of infinite variety with straight and spiral elements.(6) Facing operations of all kinds.(7) Plate and barrel cams.(8) Forging and punch press dies.(9) Jet and steam-turbine buckets, root and buckets surfaces.

(10) Indexing operations of all kinds; gear teeth, slots, flutes in twist. Slotter Machine: - It could be considerable as a vertical shaper, having only vertical movement of ram. It is mainly used for internal machining of blind holes or vertical machining of complicated shapes which are difficult to be horizontal shaper. It is very useful for making key ways, machining in square holes, cutting of internal and external teeth on big gears, machining of dies, punches etc. the job is generally supported on round table which has a rotary feed in addition to the useful table movement in cross-direction. The stroke of slotting machines ranges from 300 to 1800 mm.

The ram can be either crank driven or hydraulically driven. Ram speeds usually range from 0.05 to 2.5 mm/stroke. Cutting action takes place in downward stroke.

Type of Slotter:(1) Puncher Slotter. (2) Production Slotter.(3) Tool-room Slotter.

A Slotter Machine

SHOCK ABSORBER SECTION

The shock absorbers are of two types:(1) Escort shock absorbers.(2) Gabriel shock absorbers.

SALIENT FEATURES

1. Escorts double acting hydraulic shock absorbers are re-condition able type facilitating maximum utility and longer life.

2. Escorts shock absorbers are used for both vertical as well as lateral applications.

3. These shock absorbers have a wide range of end mounting, making them suitable for various types of rail-vehicle.

4. They have double acting independently adjustable forces in tension and compressions to suit vehicle speed are rail condition.

5. The ground and hard chrome plated piston rod is made corrosion free to provide longer and trouble free service.

6. Special oil in these shock absorbers results in operation even at higher temperatures.

7. P.T.F.E (Poly tetra Fluro Ethylene) Sealing rings with rubber pressure rings ensure higher life and consistency in damping forces.

CONSTRUCTION

Overall dimensions of the shock absorber depend upon the space availability in the vehicle under frame, the dimensional limits and the dimensions of the mounting bracket. The end mounting are designed to suit the suspension system.

Escorts shock absorbers can group into the following sub-assemblies:-

(1) Piston rod sub – assembly.(2) Cylinder sub –assembly.(3) Casing tube sub –assembly.(4) Valve sub –assembly.(5) End mounting sub –assembly.

The bottom valve seat or the cylinder bottom seals the cylinder from the bottom as well as locates the compression valve. For TV type shock absorbers a sheet metal cage is also provided with the valve seat and the cylinder for this purpose. The compression valve remains pressed against the valve seat because of the conical spring provided.

The top of the cylinder is sealed with the help of the guide disc that is pressed in to positions by the lock ring through a round cord ring and steel pressure ring. The guide disc has a PEFE sealing ring (placed in groove, inside the bore) which seals the piston rod cylindrical surface through the guide disc bore and stops any.

Leakage of oil from the cylinder. The guide disc also has a two lip oil seal which further wipes the piston rod surface and prevents the dust from coming into the cylinder with the help of the upper lip.

A part from performing these functions the guide disc also serves as a guide to keep the piston rod in an aligned position. The cylinder (compression) valve and the piston (tension) valve are basically of the same design in all the shock absorbers. The complete shock absorbing arrangement is encased within the casing tube sub-assembly with the help of a lock ring (having external threads) which is tightened from the top. The female threads provided at the top end of the casing tube are to secure this lock ring.

The piston rod reciprocates in and out of this casing tube when the shock absorbers get subjected to shocks. The piston rod top forms the top end mounting of the shock absorber. The piston is provided with the bore space (the valve area) for the tension valve to be fitted in it.

The valve seat is sealed at the top with a small round cord ring and the piston valve is located above the valve seat and is retained in position by means of a coil pressure spring. Some small holes are provided in the piston, which converge in the valve are from different points on the upper face of the piston. The piston carries a PTFE sealing ring mounting on a rubber pressure ring on its outside diameter.

The damping valve parts are held together by a high tensile hexagonal head bolt and nut, which is locked by a special tool. The area above and below the piston in the cylinder is filled completely and the area between cylinder and casing tube partly with shock absorbers oils. The cylinder must always be full of oil while the casting tube should contain sufficient oil to keep the compression valve always immersed in oil, even in the totally extended position of the shock absorber.

PRINCIPLE OF WORKING When the shock absorbers is extended the oil above the piston in the cylinder flows through the flow openings in the piston to the valve area and then it is expelled through the openings (hopes) of the spring discs and the slots of the forward discs, when the pressure is low.

When the piton moves upward the cylinder valve is lifted up against the pressure of conical spring and the oil is drawn into the area below the piston into the cylinder form the supply area between cylinder and casing tube. The amount of oil drawn corresponds to the volume of the piston rod emerging out at the top when the piston moves downwards, the valve work in the reverse order .The oil pressure increase in the area below the piston resulting in lifting of the piston valve against the tension of the coil pressure spring.

Prior to dismantling, it is absolutely essential to thoroughly remove outside contamination such as dirt, oil, etc. from the shock absorber. This is best carried out with the aid of a cleaning fluid such as trichloroethylene using suitable trays and brass wire brushes.

S. No. COMPONENT DESCRIPTION No. 1. PISTON ROD. 12. PISTRON VALVE SUB ASSY 13. SMAL VALVE SEAT 1 4. ROUND CORD RING (SMALL) 15. INTERNAL CIRCLIP 16. COIL PRESSURE SPRING 17. SEALING RING (PISTON) P.T.F.E 1 8. PRESSURE RING (PISTON) 1 9. GUIDE DISC 110. OIL SEAL 1 11. SEALING RING (P.T.F.E.) 112. PRESSURE RING 113. CYLINDER 114. CAGE 115. CONICAL SPRING 116. CYLINDER VALVE ASSY 1 17. SEALING RING (COPPER) 118. VALVE SEAT (BIG) 119. CASING TUBE WELDED SUB ASSEMBLY 120. LOCK RING 121. SCRAPER 122. RING 123. PROTECTION COVER 124. NAME PLATE 125. RIVET 426. ROUND CORD RING (BIG) 127. DISK OF PISTON ROD 128. SPRING DOWEL PIN 1 29. RUBBER DISC 430. PLATE TOP & BOTTOM 231. TAB WASHER 232. HEX NUT 233. CAP 2

Heat Treatment – shop

Total strength of workers - 06Supervisor - 01Section engineer - 01

Heat treatment - An operation of heating and cooling of metals in the solid state to induce certain desired properties into them. Heat treatment can alter the mechanical properties of steel by changing the size and shape of the grains of which it is composed, or by changing its micro-constituents. The most commonly used operations of heat treatment are:

(1) Annealing.(2) Normalising.(3) Hardening.(4) Tempering.(5) Carburisng (case- hardening)

Heat treatment

Annealing- The softening process in which iron base alloys are heated above the transformation range, held there for a proper time and cooled slowly (at rate of 30to 150 c per hour) below the transformation-rage in the furnace itself. The success of annealing depends on controlling the formation of austenite, and the subsequent transformation of the austenite at high sub-critical temperatures.

Annealing Equipments

The objects of annealing are:

(1) To soften the metal so that it can be cold worked.(2) To reduce hardness and improve mach inability.(3) To refine grain size due to phase recrystallisation and produce

uniformity.(4) To increase ductility of metal.(5) To prepare steel for subsequent heat-treatment.(6) To relieve internal stresses.(7) To produce a desired micro-structure.

Normalizing- The process in which iron base alloys are heated 40 to 50 C above the upper transformation range and held there for a specified period (to ensure that a fully austenitic structure ins produced ) and followed by cooling in still air at the room temperature.

The objects of Normalising are:

(1) TO eliminate coarse grain structure obtained during forging, rolling and stamping and produce fine grains.

(2) To increase the strength of medium carbon steel.(3) To improve the mach inability of low carbon steel.(4) To improve the structure of weld (uniformly of structure).(5) To reduce internal stresses.(6) To achieve desired result in mechanical and electrical properties.

Hardening- The heat-treating process in which steel in heated at 20*C above the transformation range, soaking at this temperature for the considerable period to ensure through penetration of the temperature inside the component, followed by continuous cooling to room temperature by quenching in water, oil or brine solution.

The effect of work hardening

The part on which hardening process is applied:

(a) As the hardness in steel is due to carbon content only, the hardening process in carried out only on high carbon steels.

(b) It is only applied on the tool and structural steels.

Purpose of hardening:

(1) To harden the steel to resist wear.(2) To enable steel to cut other metals.

Tempering- It is defined as the reheat process, reheating being carried out under sub-critical temperatures. Such a reheating permits the trapped marten site to transform into troostite or sorbets depend on the tempering temperature.

It is an operation used to modify the properties of steel hardened by quenching for the purpose of increasing its usefulness.

The effect of tempering

Tempering is divided in to three classes:

(1) Low temperature tempering.(2) Medium temperature tempering.(3) High temperature tempering.

Case Hardening- This process is used to produce a high surface hardness for wear resistance supported by a tough, shock-resisting core.

It is the process of carburisation, i.e. saturating the surface layer of steel with carbon to about 0.9% some other process by which, case is hardened and core remains soft. The carburized steel is then heated and quenched, so

that only the surface layers will respond, and the core remaining soft and tough since, its carbon content is low.

Case Hardening for Ferrite

CARRIAGE SHOP

In carriage shop, the coaches are repaired. The coach consists:

1. Frame.

2. Dash port spring.3. Bolster spring.4. Brake lock.5. Equalizing stay.6. Brake shoe key.7. Bearing piece.8. Pivot seat.9. Brake appalling frame.10. Anchor link.

Carriage Shop

1. Frame: - It is based on which the coaches rest. The whole of the coach is on the frame.

2. Dash port spring: - It is used as a shock absorber and is also knowb as a primary shock absorber its main parts are:

1. Guide.2. upper seat spring3. Guide bush.4. Lower seat spring5. Rubber washer6. Iron washer7. Brass guide ring

In lower seat oil is filled. The oil is available by “Shell Corria” or “Servo 68”.

The assembly of lower seat is:-

1. Wire spring.2. Guide ring3. Brass ring4. Rubber washer.5. Guide cap.6. Guide lock.

The oil is lower seat 750 ml and is also filled in side bearer whose capacity is 2.5 liters. 3. Bolster spring: - It is also shock absorber but generally known as a secondary stock absorber. It has lower spring and upper spring and a simple spring mounted between them.

4. Brake lock: - This is an important element of train. These are used to stop the train.

5. Equalizing stay: - This is used to hold the brake frame and coach beam together.

6. Brake shoe key: - It is used to stop the brake shoe from running out. After the brake shoe is mounted on the brake shoe hanger the key is fitted in the holes.

7. Bearing pieces: - It is the component on which the coaches or engines turns. The bearing pieces are two in number and are kept in spacially made bones that are filled with oil.

8. Pivot seat: - It is hole structure made in trolley so the pivot of the coaches May rest in it. Ti helps to the running away of coaches. As the stack adjuster moves the brake frame is pulled and brakes are applied.

9. Anchor link: - It is used for the movement of the coaches. As the coach towns the anchor link controls the movement so that the coach may remain on track, otherwise it may down from the track.

CARPENTER SHOP

LAYOUT:-

1. Total worker - 80

2. Junior engineer I - 33. Junior engineer II - 34. Senior section Engineer - 2

MAIN PURPOSE: - In this shop the wooden fitting of plies on wall, floors etc are done. The gates are also made to replace the gates that are of on use. The machine used for cutting the wood is electric and are handy.

Machine: - Machine available in carpenter shop to perform different operations are: -

1. Circular saw machine - 22. Body band saw machine - 13. Vertical band saw machine - 24. Planer machine - 1

PAINTING SHOP

LAYOUT:- 1. Total worker - 61

2. Supervisor - 43. J.E.N. - 14. Section engineer - 15. Senior Section engineer - 1

Work shop: - In this shop painting and external maintenance is carried out in two type of schedules:-

1. A-Schedule (9 days) 2. C-Schedule (5 days)

“A” Schedule (9 days)

1st day Remove old paint.2nd day One coat of red oxide zinc chromate primer.3rd day One coat of brush filler followed by spot putty to fill up holes/dents was required.4th day Filler, second coat to (including spotting where necessary).5th day Rub down with silicon carbide water proof paper Gr.120 and 220.6th day One cote of under coat. 7th day Flat with silicon carbide water proof paper Gr-320. One coat of enamel finishing.8th day Flat with silicon carbide water proof paper Gr-400.and apply a second coat of synthetic enamel finishing9th day Lettering with golden yellow and miscellaneous work (cleaning window glasses etc.)

Working of schedule “A” is carried out after 5 years or in the poor condition or coach. In this schedule total removal of old paint and repairing.

“C” schedule (5 days)

This type is schedule is carried out on the basic of coach and is independent of tome and takes place in following manner:

1st day Cleaning with soap solution or any other cleaning solution and wash thoroughly with water touch up damaged portion with primer recommended under A schedule.

2nd day Spot putty if necessary and one coat of under coat.3rd day Flat with silicon carbide water proof paper Gr-120 and 220 and apply one coat of finishing enamel.4th day Flat with silicon carbide water proof paper Gr-400.and apply a second coat of synthetic enamel finishing5th day Lettering with golden yellow and miscellaneous work

Other works:

Internal paints - White enamel paint.Side panel - Smoke gray paint.Under frame - Bituminous paint.End panel - Black enamel paint.Trolley - Bituminous paintRoof painting - Aluminum paint.

INTIRIOR PAINTING

Newly built coaches with laminated plastic panels require painting only on the steel moldings’. The moldings should be cleaned in every POH repainted with one coat synthetic enamel. If the condition of the paint on the moulding has become thick the complete paint should be removed.

The molding should then washed thoroughly allowed to dry and repainted with one coat red oxide zinc chromate primer.

Aluminum widow frames should not be painted but should be thoroughly cleaned. Laminated panels should be polished with silicon paste or similar suitable polish to restore luster and also to provide a protective coating.

PAINTING OF PARTS

The laminated plastic seats or moulded seats of synthetic materials require no painting. They should only be thoroughly cleaned with soap solution or suitable detergent.

In case of seats made of wooden battens which have been replaced should be sand papered smooth and a coat of filler should be applied.

MARKETING OF COACHES TOGETHER

Each coach should be marked with following details:

1. Coach no. owing Railway and mechanical code if any.2. Name of base station for primary maintenance.3. No of compartments and seating capacity.4. Notices for use of alarm single, safety precautions.5. Transportation code applicable to the type of coach

Carrying capacity of OCV’s to the nearest tones up to one decimal place above actual capacity.

1. Tare weights as recorded at the time of initial building or subsequent major modifications.

2. Return date showing the month and year in which the coach is required to be returned to the owing railways workshop for POH.

3. The following legends should be stenciling of necessary particulars against eacha. Make.b. Type.c. Specific gravity.d. Corrected to temperature.e. Cell watered on.f. Cell examined on.

COMPRESSOR SECTION

1. SCREW COMPRESSOR

WORKING PRINCIPLE

The screw type air compressor is a positive displacements machine like the reciprocating type. A screw compressor has two rotors housed in a cast iron casing called “stator” instead of piston and cylinder as in reciprocating. One of the rotors is called “male rotor” and the other is called “female rotor”. Drive is usually provided to male rotor, through a set of gears. Air is admitted of one end of the rotors where the matching lobe and flute first come into mesh as the rotors turn. Continued rotation brings the line of mesh past the air inlet port and then the air in the flute of the female rotor is confined by the lobe of the male rotor and stator housing. Compression Now occurs as the rotors turn further, at that time, the far and of the compressor pocket turns forwards the discharge port and air flows out in the system. The flutes of the female rotor and the lobes of male rotor correspond respectively to the cylinder and piston of reciprocating compressor.Lubricating oil is injected into the compressor unit (here to refer as air end) which in large quantities mixes directly with the air as the rotor turn compressing the air, the lubricating oil has four functions:

a) As a coolant it takes away the heat of compression.b) Seals the leakage paths amongst the rotor and housing.c) Acts as a lubricating film between the rotors allowing one rotor to directly

drive the other without a metal contact .Alsod) Lubricates the bearings and gears.

A rotary screw compressorOPERATION

The air aspirated through the air filter is compressed in the Screw Compressor driven by an electric motor. The injected oil removes the compression heat generated. This internal cooling makes possible very low compression end

temperatures. Under normal conditions the compression end temperature amounts to approx 80*C. Oil and Air are separated by the in-line 3-stage oil separator. the separated oil is re-cooled in the oil cooler and is returned to the injection point via the micro filter .This oil circulation circuit operated solely by the pressure differential does not require any oil pump.The compressed air liberated from oil in the oil-separating cartridge, except for a very small amount of residual oil, is passed to the air after cooler via the minimum pressure on return valve.

A screw compressor

Operation of screw compressor SALIENT FEATURES OF SCREW COMPRESSOR

A) LESS MAINTENANCE: - A screw compressor has only two moving parts the rotors, which do not touch each other as they are kept apart by means of a thin film of oil and hence there is no wear and tear. No reciprocating parts

like piston, piston rings, connecting rod and no suction or discharge valves to be maintained.

B) MAXIMUM RELIBILTY: - Only two moving rotors at conservative speed provide reliability never before attained in the history of compressor industry.

C) LOW DISCHARGE TEMPERATURE: - The heat of compression is taken away from the point of origin to the cooler by the injected oil and hence discharge temperature dose not exceed 115* C thereby no carbonized oils formed in the compressor and in the system.

D) VIBRATION- FREE & LOW- NOISE: - There are reciprocating mass. It has only rotating parts which are dynamically balanced and thus it is guaranteed for quite running and vibration free operation.

E) NO LOSS IN CAPACITY: - There is no wear in the solid steel screws providing no loss in capacity or performance due to wear. The compressor will provide the some airflow no matter whatever is its age.

F) PULSATION-FREE FLOW: - The unique way the screw compress the air, it gives almost pulsation free flow, which is not in the case of reciprocating machine. Hence, a screw compressor can work without a costly item called “Air Receiver”.

A complete package of screw compressor has the following major components and systems:

1) Air end (compressor Unit)2) Compressor air-inlet system.3) Compressor discharge system4) Compressor cooling and lubrication system5) Capacity control system6) Electrical system7) Safety and protective devices.8) Instrument panel.

INITIAL START-UP PRODUCE:

The following producer is to be used to make the initial start-up of the machine:

1. Read the proceeding pages of this manual 7thoroulghly.2. Be sure that all preparations and check described in the INSTALLATION SECTION have been made.3. Fill the recommended grade of oil in the sump to the required level.4. Open the ball valve of service line slightly.5. Connect the power to the unit.6. When the power supply is given control relays should be energize and power on light glows.

If control relays does not energize causes could be 1. Single phasing- Check power2. Low voltage – check voltage.3. Phase reversal –interchange R and B of incoming when above two are

satisfactory

7. Jog the unit to check the direction of rotation. Normally this should not happen when control relay closes. However due to circumstances of single-phase prevent or malfunction (oil) short-circuited; interchange the connections of R and B or incoming.8. START the compressor and check all Parameters and function of accessories used in compressor.9. Check for possible leaks in piping.10. Check all the points mentioned in Electrical system.11. Slowly close the ball valve and check the setting on the pressure switch is set correctly. If adjustments are necessary, see Control System Adjustment in the maintenance section of this manual.12. Observe the operating temperature, if the operating temperature exceeds 115’C-cooling system or installation environment should be checked. 13. Observe return line sight glass and also note the pressure drop in the maintenance gauges.14. Open the ball valve to service line.15. Re-inspect the machine for temperature and leaks, the following day.

SUBSEQUENT START-UP PROCEDURE

On subsequent starts-up, check the proper level is visible in the oil level sight glass and simply press the start-button. When the machine is running, observe the instrument panel and maintenance indicators and gauges. To shut-off the machine; press the stop button.