PROJECT REPORT

BCNHL WAGON

(BOGIE CLOSED WAGON HEAVY LOADED)

A PROJECT REPORT

Submitted by

MRIDUL MORRIS LAKRA

in partial fulfillment for the certificate

of

SUMMER TRAINING

in

PRODUCTION AND INDUSTRIAL DEPARTMENT

MODERN INDUSTRIES

G.T. ROAD, SAHIBABAD

JANUARY-FEBRUARY 2010

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MODERN INDUSTRIES, G.T. ROAD, SAHIBABAD

BONAFIDE CERTIFICATE

Certified that this project report “BCNHL (BOGIE CLOSED WAGON

HEAVY LOADED)” is the bonafide work of “MRIDUL MORRIS LAKRA” who carried out the project work under my supervision.

SIGNATURE SIGNATURE

<<Name>> <<Name>> HEAD OF THE DEPARTMENT SUPERVISOR

<<Academic Designation>>

<<Department>> <<Department>>

<<Full address of the Dept & College >> <<Full address of the Dept & College >>

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CONTENTS

1. About industry Page 4

2. Introduction Page 6

3. Standard features of wagon Page 7

4. Flow process of wagon designing Page 8

5. Cutting Page 9

6. Pressing Page 11

7. Welding processes used during fabrication Page 13

8. Center sill Page 18

9. Underframe Page 21

10. Body end Page 25

11. Body side Page 28

12. Roof Page 31

13. Door Page 34

14. Wheel mounting Page 36

15. Braking system Page 38

16. Final assembly Page 41

17. Shot blasting Page 43

18. Quality check test Page 44

19. References Page 47

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ABOUT INDUSTRY

It was in year 1941, the country’s industrial revolution was yet to come, when Modern Industries was founded in the form of Lantern Factory, as a fledgling business enterprise of young India. Since then Modern Industries has gone into a transformation of expanding and diversifying from re-rolling of Iron and Steel, Oxygen gas manufacturing and Textile to Wagon building.

Railway Wagon production was started in the year 1960. After the initial trail order of CR Wagons, later developing CRT Wagon, Modern Industries has been in the service of Indian Railways ever since. As Indian Railways modernized, and expanded in its fleet of Wagons both in terms of quantity and carrying capacity, they have tried their best to incorporate the same for their continued service to Indian Railways.

Modern Industries are the first in the country to be awarded the prestigious contract to manufacture stainless steel BOSN’CR’. The wagon floor, sides and ends are made of stainless steel, SS409(M), developed by SAIL at the Alloy Steel Plant-Salem, which controlled micro alloy addition using a new process technology.

Today Modern Industries has emerged as a leader in the manufacture of railway wagons of almost all types for its customers – an operation that it pioneered in 1961.

PRODUCTS OF COMPANY:-The company has been supplying all types of Railways Wagons to Indian Railway System for the last 40 years. Their product range includes all types of covered wagons, open wagons, tank wagons, flat wagons and hopper wagons both manually operated as well as pneumatically operated side and/or bottom discharge doors. The company has got capacity of manufacturing 1200 different types of 8-wheeler wagons per annum.

TYPES OF WAGONS:-

BTPN BOBYN

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(Tank wagon for liquid consignment) (Stone Ballast Wagon)

BCNHL BOST

(Stainless Steel Wagon) (High Sided Bogie Open Wagon) 

BCNA BOBYRN

(Water tight covered wagon) (Hopper Coal Wagon)

BLLA/B CONCOR FLAT WAGON BRNA

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INTRODUCTION

BCNHL (BOGIE CLOSED WAGON HEAVY LOADED):-

This project report illustrates the manufacturing and fabrication process of the BCNHL wagon. It is completely closed wagon which is generally used for the transportation of food grain, fertilizer and bag quantities around the country.

INTRODUCTION TO BCNHL WAGON:

This wagon was designed at 22.9t axle load in 2006. The design was made byCRF section and stainless steel materials.

Advantages of using stainless steel as base material:-1. Reduction in tare weight -more payload2. Less corrosion3. Less fuel consumption in empty running4. Less requirement of loco, crew & path 5. Extra line capacity available6. Less incidences of out of course repair 7. Reduction in turn around time of wagons due to less detentions8. Throughput enhancement

Broad Gauge bogie wagon type BCNHL having maximum axle load of 22.9 tonn has been designed by RDSO to increase the throughput over the existing BCNAHSM1 design (axle load 22.32tonn). The payload to tare ratio for BCNHL wagon is 3.4 as compared to 2.63 of existing BCNAHSM1 wagon. BCNHL wagon is useful for the transportation of bagged commodities of cement, fertilizers, foodgrain etc. The design incorporates filament of Casnub 22HS Bogies, High tensile (non transition type centre buffer coupler), Single Pipe Graduated Release air brake system. Now as an advancement twin pipe air brake system is developed.

Some assigned characteristics of BCNHL wagon are as following:-

1. Maximum axle load (loaded) 22.9 t.2. Maximum axle load ( Empty ) 5.2 t3. Maximum C.G height from Rail level (loaded) 2327mm4. Maximum C.G height from Rail level (Empty) 1134mm5. Maximum braking force at rail level 10 % of per axle axle load

The provisional speed certificate for operation of 22.9t axle load BCNHL wagon shallRemain valid up to 5 years from date of issue or before date of issue of the FinalSpeed Certificate which ever is earlier.

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STANDARD FEATURES OF ‘BCNHL’ WAGON

1. Length over head stock (mm) 100342. Length over couplers (mm) 109633. Length inside (mm) 100344. Width inside/Width Overall (mm) 3345/34505. Height inside/Height(max.) from RL. 3024/43056. Bogie centers (mm) 71537. Journal length × dia. (mm) 144x2788. Journal centers (mm) 22609. Wheel dia. on tread (New/Worn) (mm) 1000/90610. Height of C.B.C. from R.L. (mm) 110511. C.G. from R.L. (empty) (m) 113412. C.G. from R.L. (loaded) (m) 232713. Floor area (Sq.M) 33.5614. Cubic Capacity (Cu.M) 92.5415. Maximum axle load (tonne) 22.916. Tare Weight (tonne) 20.817. Pay load (tonne) 70.818. Gross load (Pay+Tare) (tonne) 91.619. Ratio gross load/Tare 4.420. Ratio (Pay load to tare) 3.421. Track Loading density (tonnes/meter) 8.3522. No. of wagons per train 5823. Brake System Air Brake24. Coupler carbon buffer coupler25. Bearing R.B.26. Maximum Speed (Loaded) 65 kmph27. Maximum Speed (Empty)

A BCNHL wagon is a closed type wagon which has following main parts- Underframe Centre Sill Roof Body end End side Wheels Bogie Braking system

All these parts are separately made and assembled together to construct a wagon. The flow process for constructing a wagon is as following:-

Firstly Underframe is completely build and is provided with fluring, gearing and then it is inspected by RDSO people and after clearing the test further assembling is done.

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FLOW PROCESS OF A BCNHL WAGONRAW MATERIAL

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SHOT BLASTING

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PAINT

CUTTINGPLASMA CUTTINGSHEAR CUTTINGCNC CUTTINGPRESSINGPOWER PRESSDROP HAMMERWELDINGMIG WELDINGARC WELDINGASSEMBLYUNDERFRAMEBODY SIDEDOORSBODY ENDROOFBRAKING SYSTEM8

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DISPATCH

CUTTING

PLASMA CUTTING:-

Plasma cutting is a process that is used to cut steel and other metals of different thicknesses (or sometimes other materials) using a plasma torch. In this process, an inert gas (in some units, compressed air) is blown at high speed out of a nozzle; at the same time an electrical arc is formed through that gas from the nozzle to the surface being cut, turning some of that gas to plasma. The plasma is sufficiently hot to melt the metal being cut and moves sufficiently fast to blow molten metal away from the cut.

The HF Contact type uses a high-frequency, high-voltage spark to ionise the air through the torch head and initiate an arc. These require the torch to be in contact with the job material when starting, and so are not suitable for applications involving CNC cutting.

The Pilot Arc type uses a two cycle approach to producing plasma, avoiding the need for initial contact. First, a high-voltage, low current circuit is used to initialize a very small high-intensity spark within the torch body, thereby generating a small pocket of plasma gas. This is referred to as the pilot arc. The pilot arc has a return electrical path built into the torch head. The pilot arc will maintain itself until it is brought into proximity of the workpiece where it ignites the main plasma cutting arc. Plasma arcs are extremely hot and are in the range of 25,000 °C (45,000 °F).[1]

Plasma is an effective means of cutting thin and thick materials alike. Hand-held torches can usually cut up to 2 in (48 mm) thick steel plate, and stronger computer-controlled torches can cut steel up to 6 inches (150 mm) thick. Since plasma cutters produce a very hot and very localized "cone" to cut with, they are extremely useful for cutting sheet metal in curved or angled shapes.

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CNC PLASMA CUTTING:-

Plasma cutters have also been used in CNC (computer numerically controlled) machinery. Manufacturers build CNC cutting tables, some with the cutter built in to the table. The idea behind CNC tables is to allow a computer to control the torch head making clean sharp cuts. Modern CNC plasma equipment is capable of multi-axis cutting of thick material, allowing opportunities for complex welding seams on CNC welding equipment that is not possible otherwise. For thinner material cutting, plasma cutting is being progressively replaced by laser cutting, due mainly to the laser cutter's superior hole-cutting abilities.

In recent years there has been even more development in the area of CNC Plasma Cutting Machinery. Traditionally the machines' cutting tables were horizontal but now due to further research and development Vertical CNC Plasma Cutting Machines are available. This advancement provides a machine with a small footprint, increased flexibility, optimum safety, faster operation.

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PRESSING

HYDRAULIC PRESS:-

Hydraulic press is used for the bending purpose. It can provide force up to 100 tons to 300 tons. Oil is used for generating force by compressing it. Oil is pulled by the motor from the reservoir and is distributed using distributor into the machine. Oil forces the plunger on the workpiece over the die. Oil is used because any other fluid might jam the pipes.

POWER HAMMER:-

Power hammer is used for shaping the workpiece. It can generate force up to 4 tons. A motor is arranged such that it uses electricity to move the hammer by generating steam. This steam pushes the hammer. Hot workpiece is used for hammering purpose.

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DROP HAMMER:-

The use of 'Drop Hammers' in manufacturing parts has been in use since the dawn of the Industrial Age. The process begins with the design of the part being laid up on a mold, transferred to the 'male and female dies' and then mounted to the drop hammer. After the inserting a piece of sheet stock between the dies and highly skilled operators will adjust the 'hammer' for the proper impact and timing to produce the part without cracking or thinning of the material.

Hammer is made up of stainless steel with higher carbon content. After switching the machine when rope is pulled manually, hammer is lifted up the machine and when rope is released then hammer falls down with a great impact and thus provides the required shape. This hammer can provide a force up to 6 tons.

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WELDING PROCEESES USED DURING FABRICATION

Modern industry is basically a fabrication and assembling company. To do the same, various types of welding techniques are used like arc welding, MIG welding, and SMAW welding. Therefore, in the following section of this report, a brief introduction of these welding techniques is given.

WELDING:-Welding is a fabrication process that joins materials, usually metals of thermoplasts, by causing coalescence. This is often done by melting the work pieces and adding a filler material from a pool of molten material that cools to become a strong joint. Sometimes pressure is used along with heat to produce the weld. Therefore, a welding process is “a materials joining process which produces coalescence of materials by heating them to suitable temperatures with or without the application of pressure of by the application of pressure alone and with or without use of filler material”.

ARC WELDING:- Arc welding is one of several fusion processes for joining metals. By applying intense heat, metal at the joint between two parts is melted and caused to intermix directly, or more commonly, with an intermediate molten filler metal. Upon cooling a metallurgical bond is created.

The arc welding process involves the creation of a suitable small gap between the electrode and the workpiece. When the circuit is made, large current flows and an arc is formed between the electrode and the workpiece. The resulting high current causes the workpiece and the electrode to melt. The electrode is consumable and includes meta for the weld, a coating which burns off to form gases which shield the weld from air and flux. When the weld solidifies a crust is formed from the impurities created in the weld process (slag). This is easily chipped away.

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ARC WELDING CIRCUIT:-The basic arc welding circuit is shown in following fig. An AC or DC power source, fitted with whatever controls may be needed, is connected by a work cable to the workpiece and by a “hot” cable to an electrode holder of some type, which a electrical contact with the welding electrode.

An arc is created across the gap when the energized circuit and the electrode tip touches the workpiece and is withdrawn, yet still within close contact. The arc produces a temperature of about 6500ºC at the tip. This heat melts both the base metal and the electrode, producing a pool of molten metal sometimes called a “crater”. The crater solidifies behind the electrode as it is moved along the joint. The result is a fusion bond.

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DEFETS OF ARC WELDING:-On the basis of working condition and operators skills there can be following defects in an arc welded part:-

1. OVERLAP:-When there is excessive molten metal either due to high temperature, slow working rate, or inappropriate electrode with low melting point then metal comes out of the root and cause defect. This is known as overlap.

2. UNDERCUT:-It is a serious welding defect in which unfilled holes or gaps are left in the root of the metals to be welded. It happens due to wrong working angle of torch, high current then the rate one, or because of high welding speed.

3. POROSITY:-In this defect, there are minute holes in the welded portion. It can be due to-

Improper gas flow Material does get solidifies properly By holding torch either to far or to close. High welding speed

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4. SPATTER:-This is the scattering of molten metal of workpiece while welding. It occurs mainly due to high current or varying welding speed.

5. CRATER:-It is the line defect in welding. Sometime welded portion gets break along a line, it is called crater. It mainly occurs due to wrong electrode or improper torch handling.

GAS METAL ARC WELDING (GMAW)/MIG:-Metal inert gas arc welding (MIG) or more appropriately called as gas metal arc welding (GMAW) utilizes a consumable electrode and hence, the term metal appears in the title.

The typical setup for GMAW (or MIG) is shown in fig. The consumable electrode is in the form of a wire reel which is fed at a constant rate, through the feed rollers. The welding torch is connected to the gas supply cylinder which provides the necessary inert gas. The electrode and the workpiece are connected to the welding power supply. The power supplies are always of the constant voltage type only. The current from the welding machine is changed by the rate of feeding of the electrode wire.

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DEFECTS OF MIG WELDING:-On the basis of working condition and operators skills there can be following defects in an arc welded part:-

1. OVERLAP:-When there is excessive molten metal either due to high temperature, slow working rate, or inappropriate electrode with low melting point then metal comes out of the root and cause defect. This is known as overlap.

2. UNDERCUT:-It is a serious welding defect in which unfilled holes or gaps are left in the root of the metals to be welded. It happens due to wrong working angle of torch, high current then the rate one, or because of high welding speed.

3. POROSITY:-In this defect, there are minute holes in the welded portion. It can be due to-

Improper gas flow Material does get solidifies properly By holding torch either to far or to close. High welding speed

4. SPATTER:-This is the scattering of molten metal of workpiece while welding. It occurs mainly due to high current or varying welding speed.

5. CRATER:-It is the line defect in welding. Sometime welded portion gets break along a line, it is called crater. It mainly occurs due to wrong electrode or improper torch handling.

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In a BCNHL wagon, various parts are welded as prescribed following:-

Centre sill SMAW welding Side body MIG welding Roof MIG welding End body MIG welding Underframe SMAW welding Crossbar MIG welding Door MIG welding

During welding in a BCNHL wagon various welding techniques are used like flat welding, horizontal welding, vertical welding, overhead welding, etc. But it is always preferred to weld as flat welding. So wherever possible, by using manipulators, workpiece is so adjusted that it can be welded as flat or horizontal. It increases the efficiency of worker and it is also safe to do so.

Wagon fixed in a manipulator

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CENTER SILL

General Description DataS.NO LOCATION NOMINAL

DIMENSIONS & ALLOWABLE

DEVIATION(mm)1 Length A1 10034,+7,-3

A22 Height and width of

end centre sillC1 327±1.5C2 530,+1.5,-0

3 Height and width of centre sill

C3 270±1.5C4 477,+1.5,-0

4 Draft gear pocket X 625.5,+0,-1.5Y 327±1.5

5 Bow 1 in 600

DESCRIPTION:-

Centre sill is the part is bears all the weight of the wagon. It is in 3 separate parts which are welded together. Each part is made of 2 separate Z sections, which are welded together. Z-section are welded after they have been drilled and finished for assembling rivets in them in later stage.

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On the two ends it has Centre filler which actually takes the weight of whole wagon. Each centre filler has Bolster which is fixed with the wheel of wagon. Stepners are provided to give strength to the structure.

3 finished center sill set

Z-sections Center part of center sill

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End part of center sill showing center filler

Fixture of a center sill

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UNDERFRAME

General Description DataS.NO. LOCATION NOMINAL

DIMENSIONS & ALLOWABLE

DEVIATION(mm)1 Length over head

stockA1 10034,+7,-3A2

2 Width over Solebar B1 3350±3B2B3B4B5

3 Distance between bolster bogie centre

C1 7153,+5,-2C2

4 Distance between side bearers centre

E1 1474±2E2

5 Diagonal difference over headstock

D1 ≤5D2

6 Camber 10,+0,-3

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DESCRIPTION:-

Main parts of Underframe are:-1. Booster: -

It bears the weight of wheels.2. Crossbar: -

This supports roof’s and body’s weight.3. Rib:-

It provides strength to center sill.4. Channel (4):-

These are fixed in the assembly to strengthen the Underframe.5. Head stock (4):-

It supports the body end weight.6. Solebar (2):-

It supports the body side weight.7. Special crossbar, Equalizer, Safety loop and Lever bracket (1 small and 1 big):-

These are provided to for air brake assembly.8. empty load:-

It take care of braking system while on load or on no load condition.9. Side barrier plate:-

It is for proper balancing of the wagon. It is on two side of bolster and has 10. Anchor, Plate and Draft:-

It is an assembly which is for connecting two wagons with each other.

Springs Anchor, Spring, and Plate

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Underframe Structure

Safety Loop, Channels, Crossbars, Solebar, and Equalizer

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Casting Bolster and Side barrier plate

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BODY END

General Description DataS.NO. LOCATION NOMINAL

DIMENSIONS & ALLOWABLE

DEVIATION(mm)1 Width over corner

stanchionA 3366±3

2 Distance between end wall centre to ventilator centre

B 411±1.5

3 End wall overall height

C1 3041±3C2

4 Distance between corner angle to outer

stanchion C.L.

D1 861±1.5D2

5 Distance between C.L. of body end to outer stanchion C.L.

E1 822±1.5E2

6 Distance between floor plate top to

centre of end

F 1023±1.5

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stiffening pressing7 Distance between

end coping to centre of end stiffening

pressing

G 1024±1.5

8 Distance between end coping to roof

top

H 985±1.5

9 Distance between corner roof car line edge to ventilator

top

J 230±1.5

DESCRIPTION:-

Body end is just for covering up the end sides of the wagons. It has a base plate of 2.5mm thickness of stainless steel. Various pressings are provided for strength purpose. There Ventilators on both the body ends of a wagon.

Body end with Ventilator and Pressings

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Fixture of Body End

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BODY SIDE

General Description DataS.NO. LOCATION NOMINAL

DIMENSIONS & ALLOWABLE

DEVIATION(mm)1 Distance between

floor sheet top to the top of coping

A1 2047±3A2

2 Overall stanchion height

B1 2059±3B2B3

3 Door opening horizontal

C1 1204, +0,-3C2

4 Door opening vertical

D1 1985,+0,-3D2

5 Distance over corner stanchions

E 10050,+7,-3

6 Diagonal difference over corners

F1 ≤5F2

7 Distance between corner stanchion to

end stanchion centre

J1 858±3J2

8 Centre distance between stanchion

to stanchion

L1 595±3L2L3L4

9 Distance between side stanchion

centre line to door

M1 939±3M2

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stanchion end10 Distance between

side stanchion centre line to door

stanchion end

H1 834±3H2

11 Body side sheet height

K1 1905±3K2K3

12 Distance between door link frame to corner stanchion

N1 1648±1N2

13 Distance between corner stanchion to

door centre

P1 2399±1P2

DESCRIPTION:-

Body side of BCNHL type wagon posses 3 different parts assembled together. Base plate is of 2.5mm thickness. Doors openings are left where doors are assembled in a later stage. In sides also pressings are provided for strength purpose

Body Side Fixture

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Body Side

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ROOF

General Description DataS.NO. LOCATION LOCATION NOMINAL

DIMENSIONS & ALLOWABLE

DEVIATION(mm)1 Distance between

roof top to top of side top coping

E1 985±3E2

2 Distance between corner roof carline

C1 10050,+7,-3C2

3 Roof inside width D1 3335±3D2D3

4 Diagonal difference over corner

F1 ≤5F2

5 Centre distance between stanchion

to stanchion

J1 595±3J2J3J4

6 Centre distance between stanchion

to stanchion

L1 641.5±3

L2

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L3L4

7 Centre distance between stanchion

to stanchion

H1 794.5±3H2

8 Distance between corner stanchion to

stanchion centre

K1 858±3K2

9 Centre distance between stanchion

to stanchion

M1 900±3M2

DESCRIPTION:-

Roof is a stainless steel rigid structure which has two main parts viz. car line and coffin line. There are 6 car lines and 8 coffin lines. Sheet used is of 1.6mm thickness. Supporting pressings are used to gain strength.

Roof Structure

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Fixture of Roof

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DOORS

General Description DataS.NO. LOCATION NOMINAL

DIMENSIONS & ALLOWABLE

DEVIATION(mm)1 Distance between

hinge centre to door edge

A1 859±1.5A2 872±1.5

2 Distance between door link bracket

frame edge to door edge

B1 743±1.5B2 756±1.5

3 Center distance between door bracket hinge

C1 305±0.5C2

4 Diagonal difference D1 ≤335

over corner D25 Center distance

between door hingeE1 86±0.5E2

6 Distance between door link bracket frame top to door

hinge bracket center

H1 45±0.5H2

7 Distance between door link bracket frame top to door hinge bracket top

G1 63±0.5G2

8 Gap between door F 3±0.5

DESCRIPTION: -Doors of a BCNHL are of stainless steel. These doors are of Slider type and whole assembly has pressings, lock, and Sliding arrangement. MIG welding is used for its assembly.

Doors

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WHEEL MOUNTING

Wheel mounting is the procedure of assembling bearing on wheels. Basic procedure of wheel mounting is as following:-

1. First of all, take bearing out of packing and mount it on the wheel set.2. Clean up the mounting space of axle of wheel with paint remover.3. Now check axle journal, dust guard and seal ring.4. Provide a coat of anti rust compound on axle and dust guard.5. Use press fit lubricant on axle before mounting the bearing.

PROCEDURE:-a) REMOVAL:-

Remove the axle end cap by removing the cap screws. Replace all locking plates. Replace axle end caps that are distorted, cracked or damaged. Inspect the cap screw threads. Cap screws that are damaged, distorted, or cracked or that cannot be tightened to the required torque must be replaced.

b) INSTALLATION:- Check axle journal, fillet, dust guards, seal wear ring grooves and upset

ends before applying bearing.

Apply a moderate to hard coating of approved anti rust compound to the axle and dust guard fillets up to wheel hub before the bearings are applied.

Coat the axle journal with an approved press-fit lubricant prior to applying bearing.

Press the bearings on the axle journal and allow the pressure to build up to the specified on the packing. Verify that there is adequate press ram travel to ensure proper seating of bearing. Mount bearings with fitted design backing ring; class E, F or G on an axle with tolerance dust guard diameter, where possible, to provide a press fit. Check the baring seating on a bearing that has non fitted design backing ring by attempting to insert a 0.050µ feeler gauge between the backing ring and axle fillet. If the feeler gauge can be inserted more than 1/8 inches, the bearing is not properly seated.

Apply the axle end caps and tighten the cap screws with a torque wrench. Recheck each cap screw several times until the cap screws do not move when the specified torque is applied.

Lock the cap screws by bending all of the locking plate tabs flat against the sides of the cap screw heads.

Check the bearing lateral play with a dial indicator mounted on a magnetic base. Revolve the several times while forcing the bearing cup towards the

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wheel hub pull the cup away from the wheel hub the bearing lateral play should be between 0.025 µ to 0.432 µ. If a tapered roller bearing rotates freely by rotating with hand, but indicates less than 0.025 µ lateral on the dial indicator, the application is satisfactory for the service.

GENERAL DATA:-

Bore diameter of cylinder 160mm Diameter of dust guard 178.562mm to 178.613mm Required pressure 350kg/cm2

Journal diameter 144.539mm to 144.564mm

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After wheel mounting process, wheel are assembled in the wagon. In this process, firstly bogie is assembled to wheel as shown in figure. Then wagon is lifted by crane and putted over the wheels such that bolster is rightly fitted at its place in wagon. After this, wheels and wagon are tightened together by rivets.

BRAKING SYSTEM

Air braking system for a BCNHL wagon has following main units:-

Main pipe Distributor valve Control chamber Brake cylinder Empty load adjuster Slack adjuster Lever mechanism Auxiliary pipe

Slack Adjuster Auxiliary reservoir

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Distributor valve and Control Brake cylinder

Chamber

Lever assembly parts Empty load adjuster

Shoe brakes

BRAKING PROCESS:-Main pipe is the only common pipe in train and is connected to DP lever in engine room. Function distributor valve is to distribute air in different braking accessories. Control valve controls the air pressure at 5kg/cm2. Brake cylinder is the unit with a piston to which main brakes are connected by a lever mechanism. Empty load adjuster plays it its role when wagon is empty. Slack adjuster maintains clearance between shoe brake and

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wheels up to 5.9mm and thus it controls the sensitivity of the braking system.. Auxiliary pipe provides extra air needed to maintain air pressure in auxiliary reservoir.

When DP leer is pulled in the engine then air flow is the main pipe in al the wagons. This main pipe is connected to the distributor valve which distributes air in auxiliary reservoir, brake cylinder and control chamber. Now when DP lever is pulled, pressure difference is created between auxiliary reservoir and brake cylinder. It causes piston to moves outwards. This outward movement of the piston is transferred to the slack adjuster and then finally to the brakes. Control chamber controls air pressure in distributor valve which in turn controls the air pressure in rest unit. Brakes are applied within 18-30 seconds after applying the brakes.

Empty load adjuster is used when wagon are unloaded. It has a lever which is moved and the pressure in brake cylinder is reduced to 3.6kg/cm2. This reduces braking force delivered by brake shoe to the wheel.

Each wagon is also provided with hand brake system which is used for manual braking. It has braking wheel at one end corner of the wagon. When this wheel is moved then by lever mechanism piston of the brake cylinder is pulled out and thus brakes are applied as discussed above.

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FINAL ASSEMBLY

General Description DataS.NO. LOCATION NOMINAL

DIMENSIONS & ALLOWABLE DEVIATION

1 Coupler height from R.L.

A1 1105,+0,-5A2

2 Floor height from R.L.

B1 1273±3B2

3 Length inside L1 11034,+7,-3L2

4 Width inside C1 3345±3

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C2C3

5 Height inside(floor level t top)

D1 2980±3

6 Length over coupler face

E1 10963,+8,-3E2

7 Side bearer clearance

- Nill

8 Overall width F1 3450±3

F2F3

9 Distance between bogie centers

G 7153±3

10 Overall height from R.L.

H1 4305±3

11 Door opening vertical

J1 1985,+0,-3J2

12 Door opening horizontal

K1 1204,+0,-3K2K3

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SHOT BLASTING

Shot blasting is the process of cleaning the assembled wagon basically for painting purpose. In this process, 1mm grit particles strike the wagon surface with a force of 75psi. After this process, 5 layer painting is done on the wagon surface to protect it from rusting.

After shot blasting and painting, wagon is inspected by RDSO quality managers and then dispatched in the main line.

Shot blasting chamber

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QUALITY CHECK TESTS

A wagon is tested by using both destructive and non-destructive techniques. Destructive techniques include compressive strength test while non-destructive tests are radiography test, water testing, visual inspection. All these tests are explained in the following sections.

RADIOGRAPHY TEST (RT):-It is a non-destructive test which is used for testing the quality of the welds in the various parts. In this test, X-rays are incident on the parts to be checked and a film is obtained as a result. This film is observed in the lab using special techniques and defects in welding are identified.

RT Machine

DI-PENETRATION TEST:-It is a non-destructive test generally used for testing the welds. This test follows the following process:-

FLORESCENT APPLICATION: - The florescent is applied all over the workpiece and it is left for 10-15 minutes. During this time, florescent gets penetrated in the porosity or pinholes.

CLEANING: - After 10-15 minutes, workpiece is rubbed and cleaned with a piece of cloth.

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DEVELOPER: - After cleaning the workpiece, developer is applied over the workpiece. After its application, florescent reappears on the surface at the point of defects and thus defects are easily visible.

1.COMPRESSIVE STRENGTH TEST:-Compressive strength is done at the last stage wagon construction process. For this test, two wagons are constructed one known as sample wagon and other is test wagon. These two are exact copies of each other. One of these is used for the test purpose. Wagon is fixed in the testing area and a load of 250 ton is applied along the axis of centre sill. Sensors are fixed on the body to note the deflection parts. Results are observed by RDSO authorities and implements are made as required. Since it is destructive test therefore, wagon under test gets crushed and observations are made on the sample wagon.

Setup for test

Load providing machine

WATER TESTING:-It is non-destructive testing technique. In this test, wagon is put under a water shower and leakages are identified in the body. It is mainly for identifying leakages in the roof and defects are removed by welding.

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Water testing unit

VISUAL INSPECTION:-It is done when wagon is completely constructed and is inspected overall for any left over defects. These are corrected at the spot and wagon is discharged in the main line.

BRAKING SYSTEM TEST:-

Braking system test is done to check the sensitivity of the brakes and any leakages in the pipes. In this test, 5kg/cm2 is provided in the main line of the braking system using a pressure generator. When air is fed then by ideal conditions, brakes should be applied is within 3 seconds. If it is not so then it is made corrected

.Pressure generating unit

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REFERENCES

RDSO data sheets Wikipedia Google

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