1. INTRODUCTION

1.1 About Indian Railway

Railways were introduced in India in April 1853. The train was first time run

between Mumbai to Thane. This distance was approximately 34km. Indian

railways is biggest setup of Asia and 4thposition of world industry. Sixteen

lakhs population associated with Indian Railway. The railway board was

established in 1905. Indian Railway is divided into 16 zonal railways. Each zonal

railway is headed by General Manager. These zonal railways are governed by

Railway Board. CRB is head person of Railway Board and he is responsible to

Ministry of Railway. CRB meets time to time with Minister of Railway and

discuss the Railway matters and takes the decisions about Railway matters.

The following organizations and offices are attached with Railway boardi.

i. RDSO

ii. Training center & Recruitments Board

iii. Zonal Railways

iv. Production units

v. Other units

1.2 Meaning of coding used:

S.No. Coding Meaning

1 BOXR Open box wagons with Screw coupling

2 BOXT Open box wagon with Transition couplers

3 BOXC box wagon with CBC at both ends and also

with CBC at one end and transition coupler at

other end.

4 BOXS Open box wagon with swing cum flap doors and sliding roof.

5 BOI Bogie open ore wagon with St. CBC (Open

Wagon Gondola)

6 BOY Bogie open ore wagon with St. CBC (CASNUB

Bogie)

7 BOXN BOXN Bogie open Box wagon with pneumatic brake

8 BOB

Bogie open wagon, hopper

9 BOBC Bogie open wagon, hopper with centre discharge

10 BOBS Bogie open wagon, hopper with side discharge

11 BOBX

Bogie open wagon, hopper with center and side

discharge

12 BOBR

Bogie open bottom rapid discharge hopper wagon

1.3 History of freight Stocks

The term freight stock means and includes all rolling stock other than coaching

stock and locomotives irrespective of contents and whether attached to a passenger

or goods train. The term wagon applies only to freight stock. Indian railways have

different types of wagons to transport different commodities like coal, cement, fertilizers,

ores, food grains, petroleum products, iron and steel and other finished products.

To cater for the transportation requirements various types of wagons having

different features are available.

During pre-independence period, British firms M/s Rendol, Palmer and Triton were

involved in providing design and development of freight stocks for Indian

Railways. During their 75 years of association with the Indian Railways they

provided design of 25 types of wagons (4-wheeler and bogie wagons) for carrying

different types of commodities. These wagons were having low axle load (16.3t) and low

pay load to tare weight ratio (ranging from 1.09 to 2.64) and were, thus, able to carry

very low volume for commodities, for example 4-wheeler wagon maximum 22 tonnes,

bogie wagon maximum 45 tonnes. These wagons were fitted with plain bearings,

vacuum brake system and screw coupling. The reliability was low along with high

ineffective and extensive maintenance requirements.

Design of 9 wagons for different applications was developed for Indian Railways

by various designers all over the world. Some of the important wagons are BOBS,

development by M/s ISW and M/s TALBOT, Germany, BWS by M/s Swiss Car Elevator

and M/s Hitachi, Japan, BWT by M/s Deutscher, East Germany, TBT by M/s CRDA, Italy

in the year 1960‟s.In 1957, Research Designs and Standards Organization of Indian

Railways was rimed by merging Central Standard Office and Railway Testing and

Research Center. The responsibility of design and development of freight stock for

Indian

Design development of freight stock has taken place in following phases–

Along with these, a large number of the types of wagons were also developed using

above bogie to cater for specific requirements of various commodities.

1.4 Background of Bogies

The first bogie wagons were introduced in 1956-57 when BOBS wagons were

imported from M/S Talbot West Germany. These were cast steel, planked bogies with un-

damped secondary suspension system.

In 1960 BOX wagons with UIC design bogies were put in service, These are capable of

higher speed, need less frequent attention and heavier trains could be formed.

Covered wagons like BCX with UIC bogies were also introduced.

In 1961-62, RDSO'S investigation revealed that there was a need for damping in

the bogies. Accordingly three types of bogies with friction damping and plank-less

cast steel construction were imported. These three bogies were the Amsted

Ride Control, National C-1 and Sumitomo SM-3bogies.

In addition to the above, RDSO has developed a new design of planked Cast

steel bogie with friction damping. The new design was introduced in 1980 -84 and called

CASNUB Bogie, which was also subsequently upgraded into seven versions. The

length of this wagon is less than the BOX wagons for the same load carried and hence

still heavier trains (with a certain fixed length due to operational considerations) could

be formed. BOXN wagons were introduced with CASNUB bogies to cope with the

increasing demands for heavier trainload and better average speeds. Covered wagons

with CASNUB bogies like BCN and BCNA were developed which run at high speeds and

form heavy trains. Well, hopper, flat and tank wagons with bogie are also

available. Different wagons are designated by different codes based upon design

features and use. Swing motion bogie is under development phase likely to be introduced

up to April 2010.

Its figure has given below:-

1.5 Criteria of classification of freight stocks

Freight stock includes all goods wagons i.e. all rolling stock other than coaching

stock, irrespective of what they carry and whether they are attached to passenger or

goods trains. Indian Railways freight stocks are broadly classified either according to its

under-gear or according to utility.

1.5.1 According to its under-gear.

1. Four Wheeled Wagon.

a. Conventional Wagon.

b. Cast steel bogie

c. Tank Wagon.

2. Bogie stock wagon:

a. Cast steel bogie.

b. Diamond frame bogie.

c. UIC fabricated bogie.

d. CASNUB bogie.

1.5.2 According to its utility

a) Open wagon.

b) Covered bogie.

c) Flat Wagon.

d) Hopper Wagon.

e) Well Wagon.

f) Container Wagon.

g) Tank wagon.

h) Explosive Wagon.

i) Brake Van.

2. DESIGN FEATURES OF FREIGHT STOCK

2.1 Structural details of freight stocks

The structural details of Freight stocks discus as under-

2.1.1 Wagon Body

The super structure attached to the under frame of freight stocks called

Wagon Body. It consists of body side and ends with their supporting structures

such as stanchions and copings, roof structures, carlines and roof sheets in

the case of covered wagons, hoppers and their supporting members in the case

porting saddles in the case of tank wagons. Doors, Door fittings, louvers for

ventilation and various fittings such as cleats, handles, hooks, footsteps and

ladders also form the part of the body.

2.1.2 Sides

Sides are made up of side panels and side stanchions which are attached to the

under frame by crib angles and body brackets. They include top copings;

intermediate copings if any, doors, door-fittings had holds tarpaulin cleats

and label-holders. Additional fittings on covered wagons are rain protection

angles above swing doors. door striking plates and anti bleeding device below the

flap doors Cattle wagons are also fitted with side louvers, beat-bar fittings and

wainscot boards.

2.1.3 Ends

Ends are similar in construction to sides in that they consists of end panel, end

stanchions, top copings and in some cases, intermediate copings. Attachment to the

under frame is by means of end floor angles and through the stanchions. Covered

wagons are provided with ventilation at the upper end of body ends. Corner

stanchions connect the ends with sides. Open wagons have reinforcing angles

at each end together with reinforcing gussets and corner pressings at the

corner. Ends of cattle wagon include wainscot boards.

2.1.4 Roof

Roofs of covered wagons consist of roof sheets and carlines. Roof sheets are

invariably much thinner than the sheets used for the body sides and end panels.

2.2 Under frame

The main members of typical conventional B.G. freight stocks under frame as

under.

i. Sole bar

ii. Head stock.

iii. Longitudinal bar

iv. Cross bars

v. Diagonals

vi. Floor

vii. Crib angle

viii. End angle

ix. Gusset plates & knee The type and size of a particular under frame are

very intimately related to the type and design of a wagon, as it constitutes

the main load bearing sub assembly for the vehicle structure,

therefore take into account the quantum and pattern of loading on

the vehicle. The overall dimensions and design of this structure,

therefore take into account the quantum and pattern of loading on

the vehicle as well as the consideration of the track, which determine

the permissible wheel base and whether a 4-wheeler or a bogie wagon

would be required for the purpose of carrying the required load.

Accordingly while designing an under frame the loading per meter run

is also taken into account as this is to be permitted by the type of

track available. The strength of under frame is also governed by

the buffing and impact loads and the shunting speeds permitted for

the marshalling of the goods stock. In the case of bogie wagons the

load transfer is carried out to the bogie frame by means of a pivot

arrangement and thus the bogie frame also assumes an equally

important function.

Fig.: Under frame BOXN Wagon

The other major sub assemblies fitted to the under frame are as under.

i. Buffer sub assembly

ii. Draw gear / CBC sub-assembly

iii. Axle guards and tie rod arrangement

iv. Container locking/anchoring arrangement (on container flats only)

v. Side stanchion & lashing chains

vi. Door operating mechanism on hopper wagons

vii. Top center pivot.

The under frame is build up of suitable rolled and pressed steel sections

strengthened by gusset plates, knees etc. Under frame of bogie wagons has

strong cross members known as bolsters for fitting upper centre pivot casting

which rests on the bogie pivot. It is a general practice to provide a positive camber

in the under frame to obviate any chances of sagging after loading in service. This

is necessary since the under frame of a bogie wagon is considerably longer

than that of a four-wheeled wagon. Trusses are provided as additional

strengthening member to avoid sagging of under frame.

2.3 Suspension

The suspension of a wagon includes the wheels bearings, axle boxes, spring, spring

links and spring brackets/scroll irons. In the case of a four wheeled wagons, the

suspension is mounted directly under the wagon under frame, whereas in

the case of bogie stock, the under frame is carried on the bogies which in turn are

supported by the springs, bearings and wheels.

The suspension system is required to cushion the riding of a vehicle on the

rails, take care of irregularities in the track and dynamic phenomena arising out of

various parasitic movements of the vehicle.

2.3.1 Four wheeler suspension

In four-wheeler wagons, the loads transmitted in the conventional arrangement via

the sole bar, scroll iron and shackles and shackle plates to the springs and thence

to the axle box, axle box key plates, bearings, journal and wheel and to the rails.

2.3.2 Eight wheeler suspension

In the suspension system of the 8-wheeled wagons, the load is transmitted to the

rails through bogie truck. Each truck consists of side frames, bolster suspension

components, wheels axles, axle boxes and other fitting such as brake gear,

trimmer etc. At present time following four types of bogies are in service :-

i. Cast steel bogie

ii. Diamond frame bogie

iii. Box bogie ( UIC Type)

iv. CASNUB Bogie

v. Swing motion bogie- Presently it is developmental phase.

2.3.2.1 Four-wheeled cast steel bogie with travel springs and snubbing

device CASNUB Bogie

There is different version of CASNUB Bogie as under:-

i. CASNUB-22W

ii. CASNUB-22W ( Retrofitted)

iii. CASNUB-22W(M)

iv. CASNUB-22NL

v. CASNUB-22NLB

vi. CASNUB-22NLM

vii. vii CASNUB-22HS

2.3.2.1.(A) Salient features of CASNUB bogie

Cast steel H frame bogies

Floating bolster

Secondary suspension with helical coil spring

Wedge type load proportional friction snubbing

Unit type fabricated brake beam

Anti rotation lugs provided between bogie bolster and

side frames.

Tapered cartridge type roller bearing axle box.

Constant up gradation of CASNUB bogie resulted in seven versions. They are

stated above.The first three are having wide jaw whereas rests have narrow jaw.

CASNUB 22W and CASNUB 22 W (M) have IRS type centre pivot in which centre

pin is provided on bogie itself. In order versions hemispherical centre pivot is

provided in which centre pin is provided on wagon under frame. Roller type side

bearer is in CASNUB 22 W version and spring loaded side bearers is in

CASNUB 22 HS version. Other versions have metal inserted rubber pad type

side bearer CASNUB22 W (M) has suspended type brake beam and other

version have guided or sliding type brake beam. A fig of CASNUB bogie is given

below

Fig.: CASNUB bogie

2.3.2.1. (B) Application of CASNUB bogie

These bogies are fitted on following freight stocks:-

i. BOXN

ii. BCN

iii. BRN

iv. BTPN

v. BOBRN etc.

2.3.2.2 Swing motion bogie

Swing motion bogie is under development phase likely to be introduced up to

April 2010. Its figure has given below:-

3.0 Braking System

Braking system used in wagons are of two types

i. Automatic vacuum brake system

ii. single pipe graduated release Air brake system

3. 1 Automatic vacuum brake system

Automatic vacuum brake system has following components

i. Vacuum cylinder suspended by tunion from under frame

ii. Piston and piston rod.

iii. Brake shaft.

iv. Brake rigging consisting mainly of pull rods and levers.

v. Hand brake (lever or screw type).

A number of improvements such as empty load device. automatic slack

adjuster and quick application-quick release valves have been introduced to

improve effectiveness of vacuum brake system. The vacuum brake system derives

its braking force from the atmospheric pressure acting on lower side of the piston

while a vacuum is maintained over the piston. The vacuum is created in the

system by ejector or exhauster provided in the locomotive.

The vacuum cylinder is divided by piston and rolling ring into two air tight

chambers called upper chamber and lower chamber. The volume of upper

chamber is kept as possible by providing a dome. The release valve is connected to

train pipe by flexible siphon pipe, the lower end of piston rod is connected to brake

shaft arm.

When vacuum is created release valve allows withdrawal of air from both

chambers and piston by its own weight comes to rest on the bottom of the cylinder

and are brakes are released. When vacuum in the train pipe is destroyed air enters

into the lower chamber, raising the piston. At this time upper chamber is disconnec

ted by rolling ring. So vacuum is still there in upper chamber. The brake shaft arm

is lifted with the movement of the piston and the brake shoes are jammed against

the tread of wheel with the help of brake rigging. The release valve when

operated allows air admission to upper chamber so that pressure is equalized on

both sides of piston and brakes are released.

A fig of automatic vacuum brake is given below:-

3. 2 Air brake system

Single pipe graduated release air brake system is used in air braked wagons.

The main components of this system are :-

i. Brake Cylinder

ii. Auxiliary reservoir

iii. control reservoir

iv. Distributor valve

v. Train pipe (brake pipe) and branch pipe

vi. Brake rigging

Brake pipe which runs throughout the length of the train has air pressure at 5

kg/sq.cm. The compressed air is supplied by compressor /expresser in the

locomotive and the brake pipes of adjacent wagons are joined by using flexible

coupling. For application of brakes, the air pressure is reduced. The drop

in pressure being proportional to the braking effort required. The drop in pressure

is sensed by the distributor valve (DV) which allows compressed air from

the auxiliary reservoir into the brake cylinder and results in brake application.

when the discharge of air from the brake pipe is stopped, the pressure of 5

kg/sq.cm. is restored and DV cuts off supply of air to the brake cylinder, thereby

releasing the brakes. The brake cylinder develops a maximum air pressure of

3.8kg/sq.cm. The reservoir is charged from brake pipe.

During application of brakes the auxiliary reservoir gets disconnected from the

brake pipe. The auxiliary reservoir has capacity of 100 liters capacity whereas

control reservoir is of 6 liters capacity. A fig of Single pipe graduated release air

brake system is given below

3. 3 Draw and Buffing Gear

There are two main arrangements of draft and buffing gear in use on

broad gauge. The older arrangement consists of a screw coupling with side

buffers, the draft load being transmitted through the screw coupling. draw hook

and draw hook springs while the buffing forces are taken by the side buffers. The

other arrangement is that of a centre buffer coupler which transmits both draft

and buffing loads. In addition to these transition CBC is also there in some

wagons. These wagons can be coupled to both St. CBC and screw coupling

wagons. The wagons having transition CBC are also provided with side

buffers.

3.4 Special type of wagons

i. Tank wagon

ii. DMT ( Departmental material truck)

iii. Well wagon

iv. Defense wagon

v. Turbine loading wagon

Here discuss only salient feature of tank wagons. There details as under:-3.6.1

Structure of Tank Wagons Tank wagons from a special class of Non-pulled

rolling stock. They are classified according to the product carried by the tank

and its design. Tank wagons fall in the following categories:-

i Tank as pressure vessels

ii Tank for corrosive liquids.

iii Tank for petrol and other highly inflammable products

iv Tank for middle distillates of petroleum.

3.5 Design feature of main type freight stocks

3.7.1 Design features of box wagons (Vacuum brake system)

i. BOX wagon was first introduced on INDIAN RAILWAY in 1960. The special

Features of the wagons are indicated below :-

1. Length over CBC 13716 mm

2. Overall width 3137 mm

3. Approximate tare wt. 25.4 tones

4. Gross weight 81.28 tones

ii. U.I.C. Bogie frame

This bogie is designed for an axle load of 20.3 tones. It has a fixed bolster

with only primary suspension incorporating 4 laminated springs. Bogie

frame is of fully welded plate construction and as such it is very easy to

repair by welding.

iii. Roller bearing & axle boxes

BOX wagons are fitted with double row cylindrical roller bearing suitable for 130

mm dia. journals. Normally these roller bearing need to attention from POH to

POH excepting topping up of grease during the schedule maintenance i.e. ROH

repair (18 months after POH/ROH). Introduction of roller bearing has

eliminated the incidence of hot axle to a great extent and has enabled the

wagon to run a long distance without any hindrance with a higher speed.

iv. Centre buffer coupler

Box wagons are fitted with center buffer coupler of knuckle type with rubber draft

gear. This introduction of CBC over conventional draw bar and buffer has

facilitated the hauling of heavier train and easy coupling and uncouplin g of

wagons within a very little time.

v. Empty load box device

These are fitted to BOX wagons to give higher leverage ratio (1:13) for

automatic adjustment of slack between brake blocks and the wheels as also to

restrict the maximum travel of piston rods.

These are fitted to BOX wagons to give higher leverage ratio (1:13) for automatic

adjustment of slack between brake blocks and the wheels as also to restrict

the maximum travel of piston rods.

Piston stroke: Empty condition - 114 to140 mm

Loaded condition - 165 to 190 mm

3.6 Design features of BOX-N wagon (Air brake system)

There are increasing demands for heavier train load, better average speeds

and higher throughput. Keeping these objectives in view the BOX-N wagon

(Broad Gauge Bogie Open Wagon Type) has been inducted in the fleet of

Rolling stock. The objective of heavier train load has been achieved by reducing

the length and by increasing the width the height of the wagon proportionately so

that maximum carrying capacity of a wagon remains same. The reduction in the

length has helped to accommodate more number of wagons in the rake. Now there

are 58 BOX-N wagons in one rake instead of 45 Nos. of BOX wagons, having

almost same carr ying capacity.

To increase through put, the BOX-N wagons are running at high speed and are

having heavier load i.e. up to 9000 tones. (In case of heavy haul trains.)

The BOX-N wagons were introduced in Indian railway 1982. Indian railways were

adopted air brake system 1968 for BOI wagons. The wagons are running in

close circuit of 7500 KMs or 30 day which ever earlier with intensive

examination/repairs every round trip at base depot.

To meet the growth of bulk traffic, a new design of bogie open wagon type BOX-N

has been evolved. This wagon exploits fully the permissible track loading

density to the maximum possible value of 7.59t/m and therefore permits operation

of 4500 t. train loads within the existing loop length of 686 metre. The special

features of this wagon are as under :-i. Cast Steel Bogie with load proportional

frictional damping and IRS spherical pivots

The wagon has been fitted with CASNUB 22 W bogie and a modified CASNUB

22W(M) bogie and incorporates load proportional friction damping with the

aid of snubber. This bogie is fitted with IRS spherical pivots.

ii.Standard tapered cartridge Roller Bearings

The wagon is fitted with standard cartridge type tapered roller bearing in order to

improve its capability for coping with lateral thrusts encountered on curves.

iii. Single Pipe Air Brake System

Since this wagon is being used on unit train operation in heavier train loads and

operating on higher speeds, the conventional vacuum brake system has been

replaced with the Single pipe graduated release air brake so that the

emergency braking distance is within the limit of 1.2 km.

iv. High Tensile Centre Buffer Coupler along with Higher Capacity Draft Gear In

order to permit the operation of heavier train loads, the strength of the

coupler has been up rated by change of material. The dimensional details

of the coupler, however, have remained unchanged and the new design of

high tensile coupler is fully interchangeable with the standard centre buffer

coupler. This up rated version of centre buffer coupler has a designed

capacity of 120 t in tension (draft force) and 270 t. in compression (buffing

force).

Further, in order to undertake the operation of long trains without excessive

damage, a new design of draft gear with higher energy absorption capacity has

been incorporated on these couplers. These draft gears incorporate friction

component along with a rubber pad/steel springs.

v. Body Construction

The various sub-assemblies of the body construction, viz. wagon sides, wagon ends

and under-frame assemblies is fully welded. These subassemblies are assembled on

the under-frame by riveting. Three doors have been provided on the side of

the wagon to permit manual on loading during emergency.

4.0 DEFECT AND FAILURE ANALYSIS OF FREIGHT

STOCK

4.1 Definition of defectsDuring intensive examination in the yard, the wagons are

detached from the rake where components are not within the prescribed tolerance

limit for maintenance. These defective wagons are then brought to depot for

repairs.

4.2 Method of reporting of defects

While examining the BOXN empty rake each and individual wagon numbers are

noted by the J.E. (C&W) with the damages and deficiencies there of, both in the

J.E. (C&W) diary and on Intensive book. The wagons warranting

detachments for attention in the depot are marked specially and a memo sent to

traffic department for information.

The wagon numbers so recorded are transferred from Intensive register into

trip register as well as in the history card. History card is provided with columns

for trip recording on one side, and the details of repairs attended in depot on the

other side.

This way each and individual wagon is monitored every day and hence by

looking at history card at a glance we can determine the number of failures with

detail and duration, at the same time the frequency of trip also can be calculated.

A format regarding billing attached Annexure I.

After pasting damage labels on the wagons at yard requiring attention in

depot, the same are placed in the depot repair line nominated for specific repairs

as under:-

Light repairs

Heavy repairs

ROH/wagons requiring lifting

The defective wagon numbers are recorded and are given to the yard staff

for shunting.

4.3.3 Classification of defects

They are divided in 6 groups and as under-

Wheel and Axel Defects

Bogie Defects

Wagon Defects

Draft Gear Defects

Brake Gear Defects

Air Brake Defects

4.4 Definition of failure

In case of wagons, normally there is no failure enroots except those wagons where

due to unsafe conditions; they are detached from the trains. Such wagons are very

few.

4.5 Analysis of failures of freight stocks

For all wagons failures a failure report is to be prepared by the DME and

submitted to the zonal headquarters. Cases of material failures are investigated

further by a "Chemist and Metallurgist" and a report is published. Cases of

bad workmanship and mismanagement by driving care are taken up on the basis of

depot records. Failure cases which result in accidents are considered to be of very

serious nature and a scale of punishment has been laid down for such cases.

A system also exists for screening repeated failures. If wagons suffer the same

problem three times in a short period then such cases are brought to the notice of

the ROH depot in charge and inspecting officials.At the national level the Research

Design and standards organization (RDSO Lucknow) maintains, Depot wise,

Rly. wise and cause wise analysis of all wagons failures and publishers

annual reports. Roller bearing failures of wagons are reviewed annually at the

national level by RDSO but the general health of the wagon fleet is

commented on only by Neutral control wing of the Indian Railways

Conferences

Association (IRCA).All cases of suggestions for change of design or

materials are brought to the consideration of the RDSO for analysis and

ordering nationwide changes. Some changes in design and materials are also

done by respective railways or ROH Depot on experimental or experience

basis.Proper failure reporting and analysis is an important activity for

ensuring proper maintenance and quality checking of components leading to

improved performance. Feed back is needed for making design improvement also.

5.0 REPAIR OF FREIGHT STOCK

5.1 Introduction

Wagons which are under repairs for an entire calendar day is infective. The

current target for ineffective wagon is 4%. The actual “Ineffective” of freight

stocks are marginally higher. Due to large fleet of wagons with variety it is

not possible to discuss the maintenance practice prescribed for each type of

wagons. The area where maintenance is required to be minimized the defects

and failure of wagon hence wagons are maximum utilized for traffic.

In the case of different types of defect created after service of stock in

mentioned components:-

Repairs to wagon body.

Repairs to under frame.

Repairs to suspension.

Repairs to Bogies.

Repairs to Brake Gear components.

Repairs to Draw & Buffing gears.

5.2 Repairs to Wagon Body

For all types of wagons the superstructure attached on to the under frame

comes under wagon body. It consists of body side & ends with their

supporting structures such as stanchions & copings, roof structure, carlines

and roof sheets in case of covered wagons, hopers & their supporting

members in case of hopper wagons & tank barrels, cladding, if any, and

supporting saddles in the case of tank wagons. Door, door fittings, louvers for

ventilation & various fittings such as cleats, handles, hooks, footsteps and ladders

also forma part of the body.

Indian Railways aim at preventive maintenance to minimize the defects &

failure of Wagon bodies and enhance the life of wagons.

The following items are checked and repaired whenever needed:

Corrosion of panel, floor plates & roof plates.

Puncturing of panels due to improper loading.

Bulging of ends due to shifting of loads.

Tearing of panels, fracture of stanchions and shearing of rivets due to

severe

impacts and shifting of loads.

Corrosion of end floor angles & crib angles.

Bulging of sides after prolonged service.

Slackening of rivets due to the combined effect of ageing, corrosion and,

wear

and tear.

Wearing out of door hinges.

Damage to door fittings because of wear and tear or mishandling.

Distortion of door mainly because of mishandling failure of welded joints.

Distortion or cracking of stanchions and other structural members because

of

abnormal load, e.g. those due to defective clamping on tipplers.

Wear and tear or breakage of miscellaneous fittings such as ladders,

cleats, label-holders etc.

5.3 Repairs to under frame

The main under frame of a wagon generally consists of 2 outer longitudinal

member‟s viz., sole bars and two headstock which are strengthened by 2

middle longitudinal and various cross members. The diagonals & gusset

plates protect the under frame against diagonal deflection and help in

absorbing and distributing the buffing loads over different members. Gussets

and knees are provided at critical locations to impart additional strength to the

joints. The whole structure is so designed that various loads are uniformly

distributed and no single member had to bear excessive load than designed

for. Various rolled sections are generally used under frame members. Channel

Sections are generally used for Headstock and sole bars for facilitating fitment of

axle guards & buffers. Riveting is generally used for joining the under frame

members. In case of the bogie wagons, the under frame has comparatively

stronger cross members known as bolster for fitting that upper centre pivot casting

which rests on the bogie pivot.

The under frame and all its members are necessarily to be rue and square and

conforming to manufacturing tolerances. All under frames are given an initial

camber at the time of manufacture so that under actual loading conditions, these

do not so. In case of bogie wagons, trusses are also provided as additional

strengthening members to avoid sagging of the under frame.

Since the under frame constitutes the main load bearing member in the wagon

which is subjected to static loads as well as dynamic impacts owing to the

unevenness in the track, wagon under frames are, therefore, checked for the

following items and repaired wherever needed :-

Buffer sub-assemblies and draw gear are within certain minimum and

maximum dimensions.

Buffer/CBC height is checked and maintained correctly.

Buffer springs are not ineffective, otherwise buffing load will have to be

directly taken by the under frame members leading to extensive.

All the rivets, especially those of axle guards, scroll irons, headstock &

knees joining the main members are checked for looseness and breakage

and replaced by sound ones at the time to POH.

The horizontal cracks in the under frames, are gauged out the welded.

The vertical cracks are strengthened by patching.

Any deflection of the members of the under frame in the form of

sagging or buckling is attended to and rectified.

Bending or cracking of the sole bars are attended to alignment of the

under frame is checked at various planes.

In case of 4 wheeler wagons, the correct location of the scroll iron

is very important for ensuring correct running of the wagons. So important

fittings like scroll irons, horn cheeks, buffer etc. are checked with

respect to important datum planes.

Degusting and cleaning of the under frame and its fitting is done.

Head stocks which are excessively damaged/bent are repaired both in

case of 4-wheelers and bogie wagons.

5.4 Repairs to Suspension

The suspension of a wagon includes the wheels, bearing, axle boxes or

adapters, springs, spring links & spring brackets/scrolls irons. In the case

of 4-wheeled wagons, the suspension is mounted directly under the wagon

under frame whereas in the case of bogie stock, the under frame is carried on the

bogies, which in turn are supported by springs, bearings & wheels. The suspension

system is required to cushion the riding of a vehicle on the rails, take care of the

irregularities in the trackand dynamic augments arising out of various parasitic

movements of the vehicle on the track. The following defects which could arise

during service are attended to:-

(A) Defects in scroll iron

Rivets loose, deficient or broken.

Scroll iron cracked or broken.

Scroll iron shifted or out of alignment.

Eye hole worn/oversize or oval.

(B) Defects in Shackle Pins

Worn out in dia. beyond permissible limits.

Broken/cracked.

Bent

Deficient or of wrong size.

Having excessive lateral clearances in its assembly.

Manufactured out of sub-standard material.

(C) Defects in Shackle Pins

Elongation of holes.

Cracks/fractures.

(D) Defects in Axle Guard Horn Cheek Assembly

Excessive wear of the axle guards.

Axle guard not square to the sole bar, both on its side and main face.

Axle guard expanded beyond permissible limits or bent.

Rivets broken/deficient or slack.

Bridle bar broken/deficient or improperly secured.

(E) Defects in Axle Boxes

Axle Box visibly worn.

More than one loose liner.

Axle Box cracked below the journal center.

Axle box broken.

Deficient back plate or dust shield.

Back top cover plate on BG wagons deficient.

Integrally cast back plate broken.

Hot box.

Axle Box overdue oiling/ or overdue repacking.

Axle box face plate broken/ insecurely fastened or gaping.

Axle box face plate deficient or with a rivet broken.

(F) Defects in Journals

Worn out collar shoulder.

Ovality on the Journal.

Tapering on the Journal

Scored Journals.

Flanges sharp/deep/thin.

Too insufficient radii at the root of flange.

Gauge slack/light.

Cracked or broken.

Slack tyres

(G) Defects in Wheel Assembly

Wheels reached condemning limits.

Flat places/skidded.

Too insufficient radii at the root of flange.

Gauge slack/light.

Cracked or broken.

Slack tyres

5.5 Repairs to Bogie

There are four types of IRS bogies, i.e.,

(i) Four wheeled Cast Steel bogie.

(ii) Four wheeled diamond frame bogie.

(iii) Four wheeled Fabricated UIC type Box bogie.

(iv) Four wheeled CASNUB bogie with long travel springs, friction snubbing

device, centre pivot and side bearer assembly. Bogies usually require attention for

the following places:

Alignment of the Bogies

i. Longitudinally

ii. Transversally

iii. Diagonally.

Corrosion & excessive pitting of spring planks. Side frames & bolsters-

cracked/distorted or pitted heavily. Uneven wear on the concave & convex

surfaces of the pivots. Spring plate corroded. Rivets of the spring plank loose. Free

height of springs reached condemning limit/springs found broken or cracked.

Cracking of the sole plate of UIC bogies above the horn

gap stiffener.

Breakage of the laminated bearing springs of UIC bogies.

Wear of Friction shoes.

Wear or various mating surfaces, like side frame,

autorotation lug, pedestal sides etc.

5.6 Repairs to Brakes Gear components

Vacuum as well as Air brake has been provided on various type of freight stocks.

The main components of brakes as under-

Brake cylinder

D.V.

SAB

Long pull rod etc.

During maintenance of freight stocks, It is required to more care has taken in

above components. Hence Reliability of freight stocks will be enhanced.

5.7 Repairs to Draw & buffing Gears

Screw coupling with side buffers in which draft load is transmitted through the

screw coupling; draw hook and draw hook springs while the buffing forces are

taken up by the side buffers.

Centre buffer coupler which transmits both draft and

buffing Loads.

There being straight CBCs & Transition type CBCs.

The buffing gear constitutes a vital equipment for the

protection of the entire wagon against damages due to

impacts.

Repairs to the various components of buffing gear are required as follows:-

Wear on the plunger on the buffing face or at the portion

of the body where it rubs against the casting.

Bending of plunger face.

Bending/cracking of buffer casing.

Bending of spindle/damage to its threads/cracking of

spindle at the cotter way.

The draw gear also constitutes a vital sub-assembly of the wagon & helps

in transmitting the tractive efforts of a loco to the individual wagons. It has to

perform this function smoothly without causing any damage to the wagon

structure. Repairs to the various components of draw gear both conventional

as well as couplings are required as under:

Wearing of hooks beyond prescribed limit.

Wear on shackle pin hole.

Wear of the shackle of screw coupling at both the eyes and

on the bend where it rubs against the hook of draw bar.

Excessive wear on trunion & Trunion nut and shackle pin.

Repairs to the various components of the CBC are required as follows:

Shank bent out of alignment with the head.

Full knuckle throw, lockset, lock-to-lock (anti-creep)

and locking functions unsatisfactorily.

Wearing of shank wear plates.

Cracking of head in the knuckle side wall.

Excessive distance between the nose of the knuckle and the

guard arm.

Knuckle nose wear stretch & cracks.

6.0 CONCLUSION

With the end of day 20, my training at BOX-N(Andal) also came to a completion. It was a

huge learning curve for me, especially as being a raw hand, I got my first opportunity to

see the practical side of things and learn various aspects of Indian Railways. For this I

would like to express my gratitude to the management at BOX-N(Andal. for having

allowed me to take my training at their company, especially Mr. D. Banerjee(SSE)

Estren Railway Andal. I would also like to express my gratitude to the various Officers

assigned to me during the training period.