VOCATIONAL SUMMER TRANING SUBMITTED TO: SUBMITTED BY: Mr. RAJBALI SADIK HUSAN WM & Principal of Roll No: 08ME43 BTC , Railway Workshop B.Tech.(ME) IIIrd Yr. Izatnagar, Bareilly F.E.T. MJPRU,BAREILLY N.E. RAILWAY BAREILLY WORKSHOP IZATNAGAR, BARILLY INDIAN RAILWAY This project would have been just a dream without a guidance and support of our CWM Mr.M P SINH & AW M/C WM Mr.RAJBALI Their role has been instrumental in the knowledge and experience that I have gained in the past 4 weeks at MECHANICAL WORKSHOP of NORTH EASTERN RAILWAY, IZATNAGAR BAREILLY. I owes my heartiest thanks to him. I would also like to thanks Mr.DC DUBEY (S.E), for giving me helpful tips at every stage. I feel blessed to be working with their team. I am grateful to the management of our college for providing all kinds of possible support, ensuring that Ichieve success in my work. Further I would like to deliver my special thanks to Mr. Ranjan Dutta (JE), Mr. Parvej Alam (INSP) and all other whose guides us with us full information. I have tried our best to learn and written briefly in my project. Indian Railways Departmental Undertaking of The Ministry of Railways, Government of Type India Rail transport Industry 16 April 1857 Founded New Delhi, Delhi, India\ Headquarters India Area served Rail transport, Cargo transport, Services, Products more... 88,355 crore (US$19.7 billion) (2009-10) Revenue 9,595 crore (US$2.14 billion) (2009-10) Net income Republic of India (100%) Owner(s) 17 Railway Zones Divisions CONTENTS: INTRODUCTION OF B.G. COACHES. AIR BRAKE SYSTEM & BOGIE WITH BRAKE GEAR MACHINES USED IN MACHINE SHOP & WHEEL SHOP CARRIAGE WORKS IN IZATNAGAR WORKSHOP INTRODUCTION OF B.G. COACH In India mainly three types of Railway coaches are running which are on the base of there guage. Broad Guage Meter Guage Narrow Guage In Izatnagar workshop Overhauling of M.G. & B.G. Coaches and locomotives are performed In India slip coach refers to a coach that is designated to terminate its journey at a station prior to the final destination of the rest of the train. The more accurate term is sectional carriage. The coach or coaches are left behind after being detached from the rest of the train. In India this is done only after the train comes to a halt; the vacuum and brake connections have to be tested before the rest of the train can leave. The term 'slip coach' is from an earlier era, however. A long time back it was the practice in the UK to uncouple some cars or coaches on the run, without stopping (this was called 'slipping' the coaches), at some stations. In such an operation, the slip coach had its own special guard who controlled the detachment, and then braked the coach as it travelled under its own momentum towards the platform at the station. This avoided delays for the main part of the train which did not have to stop at the station. This practice continued for quite some time in the UK (until the 1960s), and slip coach usually refers to this practice in British terminology. But in India the term has come to mean coaches that are detached even though they are not slipped on the run. E.g., 5014 Ranikhet Exp. from Kathgodam has 2 SL coaches and one AC-2T coach that are slip coaches for Dehradun. These are detached and attached to the 4265 Mail. Another slip coach (SL) for Jammu Tawi is detached and attached to the 3151 Express. A through coach is like a slip coach, except that it is later re-attached to another train after being detached from the first one. Thus, the passengers in the coach do not have to change trains for their destination, even if no through train exists for that route. 63,140 total kilometers covered. 8,702 passenger trains. 6,856 railway stations. 14 million passengers a day General layout of a B.G. Coach AIR BRAKE SYSTEM The ability of the railway vehicle to safely stop from the maximum speed within the specified braking distance under any conditions is one of the most important safety features. There is a rule saying that "any vehicle may start moving but every vehicle must stop". Prior to the introduction of air brakes, stopping a train was a difficult business. In the early days when trains consisted of one or two cars and speeds were low, the engine driver could stop the train by reversing the steam flow to the cylinders, causing the locomotive to act as a brake. However, as trains got longer, heavier and faster, and started to operate in mountainous regions, it became necessary to fit each car with brakes, as the locomotive was no longer capable of bringing the train to a halt in a reasonable distance. The introduction of brakes to railcars necessitated the employment of additional crew members called brakemen, whose job it was to move from car to car and apply or release the brakes when signaled to do so by the engineer with a series of whistle blasts. Occasionally, whistle signals were not heard, incorrectly given or incorrectly interpreted, and derailments or collisions would occur because trains were not stopped in time. Brakes were manually applied and released by turning a large brake wheel located at one end of each car. The brake wheel pulled on the car's brake rigging and clamped the brake shoes against the wheels. As considerable force was required to overcome the friction in the brake rigging, the brakeman used a stout piece of wood called a "club" to assist him in turning the brake wheel. In the air brake's simplest form, called the straight air system, compressed air pushes on a piston in a cylinder. The piston is connected through mechanical linkage to brake shoes that can rub on the train wheels, using the resulting friction to slow the train. The mechanical linkage can become quite elaborate, as it evenly distributes force from one pressurized air cylinder to 8 or 12 wheels. The pressurized air comes from an air compressor in the locomotive and is sent from car to car by a train line made up of pipes beneath each car and hoses between cars. The principal problem with the straight air braking system is that any separation between hoses and pipes causes loss of air pressure and hence the loss of the force applying the brakes. This deficiency could easily cause a runaway train. Straight air brakes are still used on locomotives, although as a dual circuit system, usually with each bogie (truck) having its own circuit. Two types of air brake system are : 1.Single Pipe System: 2:Twine pipe system pipe System Brake system types most frequently used for railway vehicles: Pneumatic (air pressure) brake, Electromagnetic rail brake, Hydraulic brake, Dynamic brake. Introduction The air brake is the standard, fail-safe, train brake used by railways all over the world. In spite of what you might think, there is no mystery to it. It is based on the simple physical properties of compressed air. So here is a simplified description of the air brake system. Basics A moving train contains energy, known as kinetic energy, which needs to be removed from the train in order to cause it to stop. The simplest way of doing this is to convert the energy into heat. The conversion is usually done by applying a contact material to the rotating wheels or to discs attached to the axles. The material creates friction and converts the kinetic energy into heat. The wheels slow down and eventually the train stops. The material used for braking is normally in the form of a block or pad. The vast majority of the world's trains are equipped with braking systems which use compressed air as the force to push blocks on to wheels or pads on to discs. These systems are known as "air brakes" or "pneumatic brakes". The compressed air is transmitted along the train through a "brake pipe". Changing the level of air pressure in the pipe causes a change in the state of the brake on each vehicle. It can apply the brake, release it or hold it "on" after a partial application. The system is in widespread use throughout the world. The Principal Parts of the Air Brake System The diagram shows the principal parts of the air brake system and these are described below. Compressor The pump which draws air from atmosphere and compresses it for use on the train. Its principal use is is for the air brake system, although compressed air has a number of other uses on trains. See Auxiliary Equipment. Main Reservoir Storage tank for compressed air for braking and other pneumatic systems. Driver's Brake Valve The means by which the driver controls the brake. The brake valve will have (at least) the following positions: "Release", "Running", "Lap" and "Application" and "Emergency". There may also be a "Shut Down" position, which locks the valve out of use. The "Release" position connects the main reservoir to the brake pipe . This raises the air pressure in the brake pipe as quickly as possible to get a rapid release after the driver gets the signal to start the train. In the "Running" position, the feed valve is selected. This allows a slow feed to be maintained into the brake pipe to counteract any small leaks or losses in the brake pipe, connections and hoses. "Lap" is used to shut off the connection between the main reservoir and the brake pipe and to close off the connection to atmosphere after a brake application has been made. It can only be used to provide a partial application. A partial release is not possible with the common forms of air brake, particularly those used on US freight trains. "Application" closes off the connection from the main reservoir and opens the brake pipe to atmosphere. The brake pipe pressure is reduced as air escapes. The driver (and any observer in the know) can often hear the air escaping. Most driver's brake valves were fitted with an "Emergency" position. Its operation is the same as the "Application" position, except that the opening to atmosphere is larger to give a quicker application. Feed Valve To ensure that brake pipe pressure remains at the required level, a feed valve is connected between the main reservoir and the brake pipe when the "Running" position is selected. This valve is set to a specific operating pressure. Different railways use different pressures but they generally range between 65 and 90 psi (4.5 to 6.2 bar). Equalising Reservoir This is a small pilot reservoir used to help the driver select the right pressure in the brake pipe when making an application. When an application is made, moving the brake valve handle to the application position does not discharge the brake pipe directly, it lets air out of the equalising reservoir. The equalising reservoir is connected to a relay valve (called the "equalising discharge valve" and not shown in my diagram) which detects the drop in pressure and automatically lets air escape from the brake pipe until the pressure in the pipe is the same as that in the equalising reservoir. The equalising reservoir overcomes the difficulties which can result from a long brake pipe. A long pipe will mean that small changes in pressure selected by the driver to get a low rate of braking will not be seen on his gauge until the change in pressure has stabilised along the whole train. The equalising reservoir and associated relay valve allows the driver to select a brake pipe pressure without having to wait for the actual pressure to settle down along a long brake pipe before he gets an accurate reading. Brake Pipe The pipe running the length of the train, which transmits the variations in pressure required to control the brake on each vehicle. It is connected between vehicles by flexible hoses, which can be uncoupled to allow vehicles to be separated. The use of the air system makes the brake "fail safe", i.e. loss of air in the brake pipe will cause the brake to apply. Brake pipe pressure loss can be through a number of causes as follows: A controlled reduction of pressure by the driver A rapid reduction by the driver using the emergency position on his brake valve A rapid reduction by the conductor (guard) who has an emergency valve at his position A rapid reduction by passengers (on some railways) using an emergency system to open a valve A rapid reduction through a burst pipe or hose A rapid reduction when the hoses part as a result of the train becoming parted or derailed. Angle Cocks At the ends of each vehicle, "angle cocks" are provided to allow the ends of the brake pipe hoses to be sealed when the vehicle is uncoupled. The cocks prevent the air being lost from the brake pipe. Coupled Hoses The brake pipe is carried between adjacent vehicles through flexible hoses. The hoses can be sealed at the outer ends of the train by closing the angle cocks. Brake Cylinder Each vehicle has at least one brake cylinder. Sometimes two or more are provided. The movement of the piston contained inside the cylinder operates the brakes through links called "rigging". The rigging applies the blocks to the wheels. Some modern systems use disc brakes. The piston inside the brake cylinder moves in accordance with the change in air pressure in the cylinder. Auxiliary Reservoir The operation of the air brake on each vehicle relies on the difference in pressure between one side of the triple valve piston and the other. In order to ensure there is always a source of air available to operate the brake, an "auxiliary reservoir" is connected to one side of the piston by way of the triple valve. The flow of air into and out of the auxiliary reservoir is controlled by the triple valve. Brake Block This is the friction material which is pressed against the surface of the wheel tread by the upward movement of the brake cylinder piston. Often made of cast iron or some composition material, brake blocks are the main source of wear in the brake system and require regular inspection to see that they are changed when required. Many modern braking systems use air operated disc brakes. These operate to the same principles as those used on road vehicles. Brake Rigging This is the system by which the movement of the brake cylinder piston transmits pressure to the brake blocks on each wheel. Rigging can often be complex, especially under a passenger car with two blocks to each wheel, making a total of sixteen. Rigging requires careful adjustment to ensure all the blocks operated from one cylinder provide an even rate of application to each wheel. If you change one block, you have to check and adjust all the blocks on that axle. Triple Valve The operation of the brake on each vehicle is controlled by the "triple valve", so called because it originally comprised three valves - a "slide valve", incorporating a "graduating valve" and a "regulating valve". It also has functions - to release the brake, to apply it and to hold it at the current level of application. The triple valve contains a slide valve which detects changes in the brake pipe pressure and rearranges the connections inside the valve accordingly. It either: recharges the auxiliary reservoir and opens the brake cylinder exhaust, closes the brake cylinder exhaust and allows the auxiliary reservoir air to feed into the brake cylinder or holds the air pressures in the auxiliary reservoir and brake cylinder at the current level. The triple valve is now usually replaced by a distributor - a more sophisticated version with built-in refinements like graduated release. OPERATION ON EACH VEHICLE Brake Release This diagram shows the condition of the brake cylinder, triple valve and auxiliary reservoir in the brake release position. The driver has placed the brake valve in the "Release" position. Pressure in the brake pipe is rising and enters the triple valve on each car, pushing the slide valve provided inside the triple valve to the left. The movement of the slide valve allows a "feed groove" above it to open between the brake pipe and the auxiliary reservoir, and another connection below it to open between the brake cylinder and an exhaust port. The feed groove allows brake pipe air pressure to enter the auxiliary reservoir and it will recharge it until its pressure is the same as that in the brake pipe. At the same time, the connection at the bottom of the slide valve will allow any air pressure in the brake cylinder to escape through the exhaust port to atmosphere. As the air escapes, the spring in the cylinder will push the piston back and cause the brake blocks to be removed from contact with the wheels. The train brakes are now released and the auxiliary reservoirs are being replenished ready for another brake application. Brake Application This diagram (left) shows the condition of the brake cylinder, triple valve and auxiliary reservoir in the brake application position. The driver has placed the brake valve in the "Application" position. This causes air pressure in the brake pipe to escape. The loss of pressure is detected by the slide valve in the triple valve. Because the pressure on one side (the brake pipe side) of the valve has fallen, the auxiliary reservoir pressure on the other side has pushed the valve (towards the right) so that the feed groove over the valve is closed. The connection between the brake cylinder and the exhaust underneath the slide valve has also been closed. At the same time a connection between the auxiliary reservoir and the brake cylinder has been opened. Auxiliary reservoir air now feeds through into the brake cylinder. The air pressure forces the piston to move against the spring pressure and causes the brake blocks to be applied to the wheels. Air will continue to pass from the auxiliary reservoir to the brake cylinder until the pressure in both is equal. This is the maximum pressure the brake cylinder will obtain and is equivalent to a full application. To get a full application with a reasonable volume of air, the volume of the brake cylinder is usually about 40% of that of the auxiliary reservoir. Lap The purpose of the "Lap" position is to allow the brake rate to be held constant after a partial application has been made. When the driver places the brake valve in the "Lap" position while air is escaping from the brake pipe, the escape is suspended. The brake pipe pressure stops falling. In each triple valve, the suspension of this loss of brake pipe pressure is detected by the slide valve because the auxiliary pressure on the opposite side continues to fall while the brake pipe pressure stops falling. The slide valve therefore moves towards the auxiliary reservoir until the connection to the brake cylinder is closed off. The slide valve is now half-way between its application and release positions and the air pressures are now is a state of balance between the auxiliary reservoir and the brake pipe. The brake cylinder is held constant while the port connection in the triple valve remains closed. The brake is "lapped". Lap does not work after a release has been initiated. Once the brake valve has been placed in the "Release" position, the slide valves will all be moved to enable the recharge of the auxiliary reservoirs. Another application should not be made until sufficient time has been allowed for this recharge. The length of time will depend on the amount of air used for the previous application and the length of the train. Emergency Air Brake Most air brake systems have an "Emergency" position on the driver's brake valve. This position dumps the brake pipe air quickly. Although the maximum amount of air which can be obtained in the brake cylinders does not vary on a standard air brake system, the rate of application is faster in "Emergency". Some triple valves are fitted with sensor valves which detect a sudden drop in brake pipe pressure and then locally drop brake pipe pressure. This has the effect of speeding up the drop in pressure along the train - it increases the "propagation rate". Emergency Reservoirs Some air brake systems use emergency reservoirs. These are provided on each car like the auxiliary reservoir and are recharged from the brake pipe in a similar way. However, they are only used in an emergency, usually being triggered by the triple valve sensing a sudden drop in brake pipe pressure. A special version of the triple valve (a distributor) is required for cars fitted with emergency reservoirs. Distributors A distributor performs the same function as the triple valve, it's just a more sophisticated version. Distributors have the ability to connect an emergency reservoir to the brake system on the vehicle and to recharge it. Distributors may also have a partial release facility, something not usually available with triple valves. A modern distributor will have: a quick service feature - where a small chamber inside the distributor is used to accept brake pipe air to assist in the transmission of pressure reduction down the train a reapplication feature - allowing the brake to be quickly re-applied after a partial release a graduated release feature - allowing a partial release followed by a holding of the lower application rate a connection for a variable load valve - allowing brake cylinder pressure to adjust to the weight of the vehicle chokes (which can be changed) to allow variations in brake application and release times an inshot feature - to give an initial quick application to get the blocks on the wheels brake cylinder pressure limiting auxiliary reservoir overcharging prevention. All of these features are achieved with no electrical control. The control systems comprise diaphragms and springs arranged in a series of complex valves and passages within the steel valve block. Distributors with all these features will normally be provided on passenger trains or specialist high- speed freight vehicles. Two Pipe Systems A problem with the design of the standard air brake is that it is possible to use up the air in the auxiliary reservoir more quickly than the brake pipe can recharge it. Many runaways have resulted from overuse of the air brake so that no auxiliary reservoir air is available for the much needed last application. Read Al Krug's paper North American Freight Train Brakes for a detailed description of how this happens. The problem can be overcome with a two-pipe system as shown in the simplified diagram below. The second pipe of the two-pipe system is the main reservoir pipe. This is simply a supply pipe running the length of the train which is fed from the compressor and main reservoir. It performs no control function but it is used to overcome the problem of critical loss of pressure in the auxiliary reservoirs on each car. A connecting pipe, with a one-way valve, is provided between the main reservoir pipe and the auxiliary reservoir. The one-way valve allows air from the main reservoir pipe to top up the auxiliary reservoir. The one-way feature of the valve prevents a loss of auxiliary reservoir air if the main reservoir pressure is lost. Another advantage of the two-pipe system is its ability to provide a quick release. Because the recharging of the auxiliaries is done by the main reservoir pipe, the brake pipe pressure increase which signals a brake release is used just to trigger the brake release on each car, instead of having to supply the auxiliaries as well. Two pipe systems have distributors in place of triple valves. One feature of the distributor is that it is designed to restrict the brake cylinder pressure so that, while enough air is available to provide a full brake application, there isn't so much that the brake cylinder pressure causes the blocks to lock the wheels and cause a skid. This is an essential feature if the auxiliary reservoir is being topped up with main reservoir air, which is usually kept at a higher pressure than brake pipe air. Needless to say, fitting a second pipe to every railway vehicle is an expensive business so it is always the aim of the brake equipment designer to allow backward compatibility - in much the same way as new computer programs are usually compatible with older versions. Most vehicles fitted with distributors or two-pipe systems can be operated in trains with simple one-pipe systems and triple valves, subject to the correct set-up during train formation. Self Lapping Brake Valves Self lapping is the name given to a brake controller which is position sensitive, i.e. the amount of application depends on the position of the brake valve handle between full release and full application. The closer the brake handle is to full application, the greater the application achieved on the train. The brake valve is fitted with a pressure sensitive valve which allows a reduction in brake pipe pressure according to the position of the brake valve handle selected by the driver. This type of brake control is popular on passenger locomotives. Other Air Operated Equipment On an air braked train, the compressed air supply is used to provide power for certain other functions besides braking. These include door operation, whistles/horns, traction equipment, pantograph operation and rail sanders. BOGIE MOUNTED BRAKE GEAR GENERAL In order t of slack adjuster failure as well as problemsassociated with cast iron brake blocks, adesign of brake system incorporating 8"size two cylinders on each bogie alongwith ‘K’ type high friction compositebrake blocks has been introduced. DESIGN FEATURES OF THESYSTEM This type of system is exactly similar tothe standard air brake system except forthe following: Four cylinder of 8" size is providedfor each coach in place of twocylinders of 14" in standard air brake system. These cylinders havebuilt in single acting slack adjusterfor taking the slack created betweenwheel and brake block on account of wheel / brake block wear. Mountingof cylinders is done on either side of the bogie frame in between centrallongitudinal members connecting thebogie transom to the headstocks.Each cylinder controls the brakingon one wheel set. Each cylinder hasa piston take up stroke of 32 mm andadjustment capacity of 305 mm High friction composite brake blocksof ‘K’ type have been used.d) Bogie brake rigging has beenmodified to incorporate a totalmechanical advantage of 7.644 perbogie for non-AC coaches and 8.40per bogi e for AC coaches. Curved profile pull rods have beenused to interconnect leverscontrolling braking one wheel set.These pull rods provided with oneadditional hole for the adjustment of slack between wheel and block afterspecified amount of wear.f) Since brake cylinders have beenmounted on the bogie frame, 15mm.bore pneumatic pipeline has beenlaid over bogie frame to interconnect the brake cylinders of onebogie. Output pipe line of distributorvalve has been connected to bogiepneumatic line through flexiblehoses to provide flexibility toalround dynamic movement.603 COMPOSITE BRAKE BLOCK General Low friction composite brake blockshave the following benefits: Reduced braking distance due touniform co-efficient of friction. Reduced weight Reduction in the replacement of brake blocks vis a vis cast iron due tohigher wear life in train operation. Reduced wear and tear of brakerigging. Reduced noise during braking. Characteristics of composition brakeblocks Composition of material The composition of materialconstituting the brake blocks must bechosen to give the best balancebetween : The braking characteristics The wear and service life of blocks Wear on the running surface of thewheels The effect on adhesion between therail and wheel Requirement concerning friction REQUIRED MACHINES FOR MACHINE SHOP & WHEEL SHOP INTRODUCTION: In Izatnagar Railway N.E. mechanical workshop are mostly common maschines are used in the operations of machine and wheel shops. Some operations of machine shop are operated in the wheel shop and vice versa. The work of machine shop is to machine the parts required for POH work as per drawing and instruction. In this shop mass removel process are executed with the help of different types of machines These machines perform following operations during the POH of locomotives and coaches in the IZATNAGAR RAILWAY WORKSHOP with the use of many types of machines. Types of machining operation There are many kinds of machining operations, each of which is capable of generating a certain part geometry and surface texture. Turning A cutting tool with a single cutting edge is used to remove material from a rotating workpiece to generate a cylindrical shape. The speed motion in turning is provided by the rotating workpart, and the feed motion is achieved by the cutting tool moving slowly in a direction parallel to the axis of rotation of the workpiece operations are operations that rotate the workpiece as the primary method of moving metal against the cutting tool. Lathes are the principal machine tool used in turning. Drilling It is used to create a round hole. It is accomplished by a rotating tool that is typically has two or four cutting edges. The tool is fed in a direction parallel to its axis of rotation into the workpart to form the round hole. Boring The tool is used to enlarge an already available hole. It is a fine finishing operation used in the final stages of product manufacture. Milling A rotating tool with multiple cutting edges is moved slowly relative to the material to generate a plane or straight surface. The direction of the feed motion is perpendicular to the tool's axis of rotation. The speed motion is provided by the rotating milling cutter. The two basic forms of milling are: Peripheral milling Face milling Knurling Knurling is a manufacturing process, typically conducted on a lathe, whereby a visually attractive diamond-shaped (criss-cross) pattern is cut or rolled into metal. This pattern allows hands or fingers to get a better grip on the knurled object than would be provided by the originally smooth metal surface. Occasionally, the knurled pattern is a series of straight ridges or a helix of "straight" ridges rather than the more-usual criss-cross pattern. Knurling may also be used as a repair method: because a rolled-in knurled surface has raised-up areas surrounding the depressed areas, these raised areas can make up for wear on the part. In the days when labor was cheap and parts expensive, this repair method was feasible on pistons of internal combustion engines, where the skirt of a worn piston was expanded back to the nominal size using a knurling process. As auto parts have become less expensive, knurling has become less prevalent than it once was, and is specifically recommended against by performance engine builders. Knurling can also be used when a high precision component will be assembled into a low precision component, for example a metal pin into a plastic molding. The outer surface of the metal pin is knurled so that the raised detail 'bites' into the plastic irrespective of whether the size of the hole in the plastic closely matches the diameter of the pin. Chamfering Chamfering is part of the process of hand-crafting a parabolic glass telescope mirror. Before the surface of the disc can be ground, the edges must first be chamfered to prevent chipping. This can be accomplished by placing the disc in a metal bowl containing silicon carbide and rotating the disc with a rocking motion. The grit will thus wear off the sharp edge of the glass. Grinding Grinding is an abrasive machining process that uses a grinding wheel as the cutting tool Facing A lathe can be used to create a smooth, flat, face very accurately perpendicular to the axis of a cylindrical part. First, clamp the part securely in a lathe chuck. Then, install a facing tool. Bring the tool approximately into position, but slightly off of the part. Always turn the spindle . before turning it on. This ensures that no parts interfere with the rotation of the spindle. Move the tool outside the part and adjust the saddle to take the desired depth of cut. Then, feed the tool across the face with the cross slide. The following clip shows a roughing cut being made; about 50 thousandths are being removed in one pass. If a finer finish is required, take just a few thousandths on the final cut and use the power feed. Be careful clearing the ribbon-like chips; They are very sharp. Do not clear the chips while the spindle is turning. After facing, there is a very sharp edge on the part. Break the edge (205kB) with a file. Parting A parting tool is deeper and narrower than a turning tool. It is designed for making narrow grooves and for cutting off parts. When a parting tool is installed, ensure that it hangs over the tool holder enough that the the holder will clear the workpiece (but no more than that). Ensure that the parting tool is perpendicular to the axis of rotation and that the tip is the same height as the center of the part. A good way to do this is to hold the tool against the face of the part. Set the height of the tool, lay it flat against the face of the part, then lock the tool in place. When the cut is deep, the side of the part can rub against sides of the groove, so it's especially important to apply cutting fluid. In this clip, a part is cut off from a piece of stock. Treading & Chasing: Taps and dies are cutting tools used to create screw threads, which is called threading. A tap is used to cut the female portion of the mating pair (e.g., a nut). A die is used to cut the male portion of the mating pair (e.g., a screw). The process of cutting threads using a tap is called tapping, whereas the process using a die is called threading. Both tools can be used to clean up a thread, which is called chasing. Cutting tool . Different machines used in Machine shop & Wheel shop are: 1. Radial drill machinE 2. Centre lathe machine 3. Horizontal Boring machine 4. Vertical boring machine 5. Horizontal milling machine 6. Vertical milling machine 7. Slotting machine 8. Capstan lathe 9. Turret lathe 10.Different types of CNC machines 11.Wheel turning lathe 12.Wheel axle lathe 13.CNC turning centre 14.Combination lathe machine 15.Wheel lathe 16.Brake lathe etc….. Lathe (metal) Center lathe with DRO and chuck guard. Size is 460 mm swing x 1000 mm between centers A metal lathe or metalworking lathe is a large class of lathes designed for precisely machining relatively hard materials. They were originally designed to machine metals; however, with the advent of plastics and other materials, and with their inherent versatility, they are used in a wide range of applications, and a broad range of materials. In machining jargon, where the larger context is already understood, they are usually simply called lathes, or else referred to by more-specific subtype names (toolroom lathe, turret lathe, etc.). These rigid machine tools remove material from a rotating workpiece via the (typically linear) movements of various cutting tools, such as tool bits and drill bits Parts of lathe machine are: Drilling Machine: Drilling Machine is somewhat special purpose machine and somewhat general purpose machine. I am calling it special purpose machine because it is used for drilling related operation and general purpose because it can perform many operations like that of driPrinciple of Drilling Machine Parts of Drilling Machine: There are various kinds of Drilling Machine depending on their use. 1. Drilling Head. 2. Feeding Mechanism. 3. Supporting Column. 4. Chuck or Tool Holder. 5. Drive Mechanism. 6. Work Table with Tee Slots. Types of Drilling Machine: Here are some kinds of drilling machines. Sensitive Drilling Machine. Upright Drilling Machine. Radial Drilling Machine. Multiple Spindles Drilling Machine. Deep Hole Drilling Machine. Portable Drilling Machine. Automatic Drilling Machine. Operations Performed on Drilling Machine: Drilling Machine can perform various machining operations which are related to drilling. 1. Drilling. 2. Tapping. 3. Reaming. 4. Counter Sinking. 5. Counter Boring. 6. Boring. 7. Tee Slot Cutting. 8. Grinding. CNC lathe / CNC turning center: Its machine is mainly used in wheel shop for turning of wheel profil in Izatnagar workshop. CNC lathe with milling capabilities An example turned vase and view of the tool turret CNC lathes are rapidly replacing the older production lathes (multispindle, etc.) due to their ease of setting and operation. They are designed to use modern carbide tooling and fully use modern processes. The part may be designed and the toolpaths programmed by the CAD/CAM process, and the resulting file uploaded to the machine, and once set and trialled the machine will continue to turn out parts under the occasional supervision of an operator. The machine is controlled electronically via a computer menu style interface, the program may be modified and displayed at the machine, along with a simulated view of the process. The setter/operator needs a high level of skill to perform the process, however the knowledge base is broader compared to the older production machines where intimate knowledge of each machine was considered essential. These machines are often set and operated by the same person, where the operator will supervise a small number of machines (cell). The design of a CNC lathe has parts are still recognizable, the turret holds the tools and indexes them as needed. The machines are often totally enclosed, due in large part to Occupational health and safety (OH&S) issues. With the advent of cheap computers, free operating systems such as Linux, and open source CNC software, the entry price of CNC machines has plummeted. Swiss-style lathe / Swiss turning center A view inside the enclosure of a CNC Swiss-style lathe/screw machine. For work requiring extreme accuracy (sometimes holding tolerances as small as a few tenths of a thousandth of an inch), a Swiss-style lathe is often used. A Swiss-style lathe holds the workpiece with both a collet and a guide bushing. The collet sits behind the guide bushing, and the tools sit in front of the guide bushing, holding stationary on the Z axis. To cut lengthwise along the part, the tools will move in and the material itself will move back and forth along the Z axis. This allows all the work to be done on the material near the guide bushing where it is more rigid, making them ideal for working on slender workpieces as the part is held firmly with little chance of deflection or vibration occurring. This style of lathe is also available with CNC controllers to further increase its versatility. Most CNC Swiss-style lathes today use one or two main spindles plus one or two back spindles (secondary spindles). The main spindle is used with the guide bushing for the main machining operations. The secondary spindle is located behind the part, aligned on the Z axis. In simple operation it picks up the part as it is cut off (aka parted off) and accepts it for second operations, then ejects it into a bin, eliminating the need to have an operator manually change each part, as is often the case with standard CNC turning centers. This makes them very efficient, as these machines are capable of fast cycle times, producing simple parts in one cycle (i.e. no need for a second machine to finish the part with second operations), in as little as 10–15 seconds. This makes them ideal for large production runs of small-diameter parts. Additionally, as many Swiss lathes incorporate a secondary spindle, or 'sub-spindle', they also incorporate 'live tooling'. Live tools are rotary cutting tools that are powered by a small motor independently of the spindle motor(s). Live tools increase the intricacy of components that can be manufactured by the Swiss lathe. For instance, automatically producing a part with a hole drilled perpendicular to the main axis (the axis of rotation of the spindles) is very economical with live tooling, and similarly uneconomical if done as a 'secondary operation' after machining by the Swiss lathe is complete. A 'Secondary operation' is a machining operation requiring a partially completed part to be secured in a second machine to complete the manufacturing process. Generally, advanced CAD/CAM software uses live tools in addition to the main spindles so that most parts that can be drawn by a CAD system can actually be manufactured by the machines that the CAD/CAM software support. Combination lathe / 3-in-1 machine A combination lathe, often known as a 3-in-1 machine, introduces drilling or milling operations into the design of the lathe. These machines have a milling column rising up above the lathe bed, and they utilize the carriage and topslide as the X and Y axes for the milling column. The 3-in-1 name comes from the idea of having a lathe, milling machine, and drill press all in one affordable machine tool. These are exclusive to the hobbyist and MRO markets, as they inevitably involve compromises in size, features, rigidity, and precision in order to remain affordable. Nevertheless, they meet the demand of their niche quite well, and are capable of high accuracy given enough time and skill. They may be found in smaller, non-machine-oriented businesses where the occasional small part must be machined, especially where the exacting tolerances of expensive toolroom machines, besides being unaffordable, would be overkill for the application anyway from an engineering perspective. Mini-lathe and micro-lathe Mini-lathes and micro-lathes are miniature versions of a general- purpose center lathe (engine lathe). They typically have swings in the range of 3" to 7" (70 mm to 170 mm) diameter (in other words, 1.5" to 3.5" (30 mm to 80 mm) radius). They are small and affordable lathes for the home workshop or MRO shop. The same advantages and disadvantages apply to these machines as explained earlier regarding 3- in-1 machines. As found elsewhere in English-language orthography, there is variation in the styling of the prefixes in these machines' names. They are alternately styled as mini lathe, minilathe, and mini-lathe and as micro lathe, microlathe, and micro-lathe. Wheel lathe A lathe for turning the wheels of railway locomotives and rolling stock. Brake lathe A lathe specialized for the task of resurfacing brake drums and discs in automotive or truck garages. CARRIAGE WORKS IN IZATNAGAR WORKSHOP CARRIAGE WORKS: Following carriage works are operated under the carriage shop 1:Inspection 2:Corrosion 3:Furnishing 4:Paintig 5:Braking System 1:Inspection The Indian Railways serve as the principal mode of passenger transport in the country. It therefore, needs well maintained coaching stock for transportation of coaching traffic efficiently, safely and punctually. The productivity of a network like that of the Railways depends, to a large measure, on its fleet of coaches being well maintained. An effective and efficient coach maintenance system should have timely preventive maintenance to avoid occurrence of predictable defects, apart from attending to repairs promptly, so as to keep the coaches fit for traffic and to provide the desired riding quality, passenger comfort and safe running condition. Further, detention of rolling stock for maintenance should be kept to the barest minimum. All Passenger Coaching Vehicles (PCVs) owned by individual Railways, are allotted by the Chief Mechanical Engineer to a base depot for primary maintenance and a base workshop for periodical overhaul (POH) and special repairs. As the basic maintenance of coaches is done in workshops during POH, special efforts are necessary to ensure good workmanship and to assure quality of repair during POH in workshop so that the coaches give reliable service on line. 2:Corrosion Corrosion is the disintegration of an engineered material into its constituent atoms due to chemical reactions with its surroundings. In the most common use of the word, this means electrochemical oxidation of metals in reaction with an oxidant such as oxygen. Formation of an oxide of iron due to oxidation of the iron atoms in solid solution is a well-known example of electrochemical corrosion, commonly known as rusting. This type of damage typically produces oxide(s) and/or salt(s) of the original metal. Corrosion can also refer to other materials than metals, such as ceramics or polymers, although in this context, the term degradation is more common. In other words, corrosion is the wearing away of metals due to a chemical reaction. Many structural alloys corrode merely from exposure to moisture in the air, but the process can be strongly affected by exposure to certain substances (see below). Corrosion can be concentrated locally to form a pit or crack, or it can extend across a wide area more or less uniformly corroding the surface. Because corrosion is a diffusion controlled process, it occurs on exposed surfaces. As a result, methods to reduce the activity of the exposed surface, such as passivation and chromate- conversion, can increase a material's corrosion resistance. However, some corrosion mechanisms are less visible and less predictable. Rust, the most familiar example of corrosion. CORROSION IN RAILWAY The most common form of corrosion of rails is atmos-pheric corrosion, resulting from the wetting and drying process. The atmospheric corrosion of rails results in uni-form corrosion. Corrosion will be more severe for longer moisture residence time and frequent wetting and drying. Uniform corrosion will be aggravated in the presence of chloride ions, because they destabilize the protective rusts on the surface 9 . For this reason, rails laid near coastal re-gions are more prone to atmospheric corrosion, warrant-ing more frequent replacement than rails in a dry climate. Of far more importance, from both economic and safety perspectives, is the enhanced corrosion that takes place at certain localized locations. There are two origins for the occurrence of localized corrosion in Indian rails. The first cause is due to leakage of current in electri-fied railway systems 10 . Intense corrosion attack take life of C– Mn steel-based rail to nearly half its expected life 2 (A. Jain and P. Funkwal, unpublished). An analysis of rail renewal in India for 2006– 2007 (A. Jain and P. Funkwal, unpublished) indicates that only 32% of the replacement of rails took place after completion of normal expected life of the rails. Data show that 37% of the rails undergo replacement due to corrosion before their estimated service life, whereas only 16% of the rail replacement is due to wear and 15% due to rail-weld fail-ure (A. Jain and P. Funkwal, unpublished). Modern rails are normally eutectoid steels, i.e. high carbon steels containing about 0.70–0.80 wt% carbon. These steels possess a fully pearlitic microstructure, which provides a good combination of strength, hardness and ductility. However, the presence of a high amount of cementite in pearlite renders the structure susceptible to corrosion 3 . This article highlights the recent rail steel development activities focused on corrosion prevention of rails for the Indian railways, undertaken as a academia–industry– user (IIT Kanpur–Steel Authority of India (SAIL)–Indian Railways) collaborative research programme, to develop a novel rail steel of relatively improved corrosion per-formance than the standard rail steel currently in use. Under the aegis of the Technology Mission for Railway Safety (TMRS), initiated by the Ministry of Railways, the three institutions were brought together to find a solution to the acute corrosion problem faced by Indian Railways. The research team from IIT Kanpur was instrumental in planning the rail steel compositions and was responsible for carrying out experimental studies. The work was completed with additional efforts put together by the industrial partner, Bhilai Steel Plant (SAIL), which was responsible for manufacturing the rail steel plates on an experimental basis as well as manufacturing the actual novel corrosion-resistant rail. In this context, the different forms of corrosion that are noted in rails and the rail fastening system, especially under Indian conditions, will be first considered in this article. rovidedSome relevant experimental details related to corrosion performance of actual rail samples will also be p. TYPES OF CORROSION 1:Galvanic corrosion Galvanic corrosion occurs when two different metals electrically contact each other and are immersed in an electrolyte. In order for galvanic corrosion to occur, an electrically conductive path and an ionically conductive path are necessary. This effects a galvanic couple where the more active metal corrodes at an accelerated rate and the more noble metal corrodes at a retarded rate. When immersed, neither metal would normally corrode as quickly without the electrically conductive connection (usually via a wire or direct contact). Galvanic corrosion is often utilized in sacrificial anode. What type of metal(s) to use is readily determined by following the galvanic series. For example, zinc is often used as a sacrificial anode for steel structures, such as pipelines or docked naval ships. Galvanic corrosion is of major interest to the marine industry and also anywhere water can contact p] Pitting corrosion 2:Pitting corrosion The scheme of pitting corrosion Certain conditions, such as low concentrations of oxygen or high concentrations of species such as chloride which compete as anions, can interfere with a given alloy's ability to re-form a passivating film. In the worst case, almost all of the surface will remain protected, but tiny local fluctuations will degrade the oxide film in a few critical points. Corrosion at these points will be greatly amplified, and can cause corrosion pits of several types, depending upon conditions. While the corrosion pits only nucleate under fairly extreme circumstances, they can continue to grow even when conditions return to normal, since the interior of a pit is naturally deprived of oxygen and locally the pH decreases to very low values and the corrosion rate increases due to an auto-catalytic process. In extreme cases, the sharp tips of extremely long and narrow corrosion pits can cause stress concentration to the point that otherwise tough alloys can shatter; a thin film pierced by an invisibly small hole can hide a thumb sized pit from view. These problems are especially dangerous because they are difficult to detect before a part or structure fails. Pitting remains among the most common and damaging forms of corrosion in passivated alloys, but it can be prevented by control of the alloy's environment. . 3:Microbial corrosion Microbial corrosion, or bacterial corrosion, is a corrosion caused or promoted by microorganisms, usually chemoautotrophs. It can apply to both metals and non-metallic materials, in both the presence and lack of oxygen. Sulfate-reducing bacteria are common in lack of oxygen; they produce hydrogen sulfide, causing sulfide stress cracking. In presence of oxygen, some bacteria directly oxidize iron to iron oxides and hydroxides, other bacteria oxidize sulfur and produce sulfuric acid causing biogenic sulfide corrosion. Concentration cells can form in the deposits of corrosion products, causing and enhancing galvanic corrosion. Accelerated Low Water Corrosion (ALWC) is a particularly aggressive form of MIC that affects steel piles in seawater near the low water tide mark. It is characterised by an orange sludge, which smells of Hydrogen Sulphide when treated with acid. Corrosion rates can be very high and design corrosion allowances can soon be exceeded leading to premature failure of the steel pile. Piles that have been coating and have cathodic protection installed at the time of construction are not susceptible to ALWC. For unprotected piles sacrificial anodes can be installed local to the affected areas to inhibit the corrosion or a complete retrofitted sacrificial anode system can be installed. Affected areas can also be treated electrochemically by using an electrode to first produce chlorine to kill the bacteria, and then to produced a calcareous deposit, which will help shield the metal from further attack. 3:Furnishing Furnishing is the process of decoration of different passenger using acceceries in the bogies. Changing the sheets, fans, washers , etc. during POH of trains is called furnishing process. Decorative Laminated Sheet PVC Flooring Rexine for Berths Ironically , in the decision taken for increased periodicity, it was also decided that the Bogie shall be sent by the divisions to the Repair Workshops every 9 months. Earlier the coaches along wih the bogie was comming to the workshop for POH when the material used was not yet upgraded. However, with th introduction of upgraded material in the bogie, the POH/ IOH i.e maimtainance required at the repair Workshops should have increased beyond 12 moths . However, inspite of introduction of upgraded material, the maintainance requirement of the bogie has been reduced to 9 months , much lower than the 12 months which was earlier the case when non upgraded material was bieng used. Why should a bogie com for IOH in the eworkshop in 9 months which has upgraded material which is supposed to last for 2 POH cycles i.e 36 months. 4:Paintig Painting is the important part of carriage shop during overhauling period. Painting is done mainly in the shell portion of the coaches. B.G. coach is required more painting works then other types of coaches. Its prevents the material from corrosion and used for decorates the rail components. 5:Braking System Brakes are used on the cars of railway trains to enable deceleration, control acceleration (downhill) or to keep them standing when parked. While the basic principle is familiar from road vehicle usage, operational features are more complex because of the need to control multiple linked carriages and to be effective on vehicles left without a prime mover. Clasp brakes are one type of brakes historically used on trains. During overhauling period defected braking system equipments are replaced and coated by anticorrosive materials.