BRAKE BINDING Brake binding is a

phenomenon of binding of

wheels by brake blocks

when the loco pilot’s brake

valve is in release position.

• Train running heavy with push back

tendency.

• Train does not move during starting

on prescribed notch/current.

• Rise in temperature and emission of

smoke from affected wheels.

• Unusual sound due to binding of

wheels by brake blocks.

• Skidding of wheels on rail.

SIGNS & SYMPTOMS

MAIN CAUSES

• Defective DV/mal functioning of DV.

• Air leakage from DV, AR, Dirt

collector, angle COC and branch

pipes.

• Jamming of brake cylinder piston.

• Jamming of brake gear levers, pins,

brake beam hangers etc.

• Hand brake is in applied condition.

1) BRAKE PIPE

2) FEED PIPE

3) BRAKE CYLINDER

4) AUXILARY RESERVIOR

5) ISOLATION COCK WITH FILTER

6) DISTRIBUTOR VALVE

7) CONTROL RESERVIOR

8) ISOLATING COCK

9) CHECK VALVE WITH COCK & ISOLATING COCK

10) CUT OFF ANGLE COCK

11) HOSE COUPLING FOR BRAKE PIPE

12) HOSE COUPLING FOR FEED PIPE

13) EMERGENCY BRAKE VALVE

14) MANUAL RELEASE

15) PASS.EMERGENCY ALARAM VALVE ASSEMBLY

16) PRESSURE GAUGE

SCHEMATIC DIAGRAM FOR AIR BRAKE

BRAKE BINDING

ON ONE TROLLY

ON BOTH TROLLEYS

ONLY ONE TROLLY AFFECTED

Binding with BK.Cyl in

release condition Binding with BK.Cyl in

operative condition

Rotate SAB

SAB rotating SAB stuck up

Release BK

rigging by

rotating

SAB

Release BK

rigging by

removing palm

end pin

Dummy BK cyl. Work

train upto destination

Binding with BK.Cyl in operative condition

Operate QRV of DV

If BK cyl. released

Isolate BK cyl.

isolating cock

Isolate FP & AR isolating cock,

Isolate the DV and pull QRV

If piston

releases

If BK cyl. Does not release

Leave DV in isolate

condition

If piston does not

release

Isolate BK cyl. And pull

drain plug of BK cyl

QRV

ROTATE TO

ISOLATE DV

BOTH TROLEYS AFFECTED

Operate QRV of DV

If piston released

Isolate BK

cyl. & DV

Isolate FP & AR isolating

cock, isolate DV & Pull

QRV again

If piston does not

release

If piston

released

Leave DV in

isolating

condition

If piston does not

release

Open AR drain

cock & if piston

does not release

Isolate both cyl.&

open drain plug

of BK cyl.

ROTATE TO

ISOLATE DV

QRV

BMBS TROLLEYS AFFECTED

BRAKE PIPE

PRESSURE GAUGE

FEED PIPE

PRESSURE GAUGE FP

ANGLE COCK

ALARAM PULL CHAIN

SCHEMATIC DIAGRAM OF

BMBS AIR BRAKE SYSTEM

GD’S

EVB

BP

ANGLE COCK

AR

ISOLATING

COCK

AR

BP

ISOLATING COCK

BRAKE PIPE

FEED PIPE

PEAV

ISOLATING COCK

PEAV

CR DV

QRV

ISOLATING HANDLE

BC ISOLATING COCK

BC BC

DRAIN COCK

STEPS TO RELEASE

BRAKE BINDING

STEP-1

STEP-2

Close isolating cock of

BP & FP branch pipe line

Isolate DV by moving the

handle from vertical to

horizontal position & secure

BP

FP

STEP-3 Release DV by pulling QRV

till all the air escaped

Through DV

STEP-4 Close both bogie brake

Isolating cocks

STEP-5

Pull out the clutch &

rotate spindle rod

clock wise to

release the piston

FOR SLR

COACHES

Check hand brake and

ensure gap between

wheel and brake block.

Reset the PEAV & if not

success isolate the

PEAV isolating cock

IF ACP ON

COACHES

AIR BARKE SYSTEM ON LHB COACHES

(Axle Mounted Disc Brake)

Axle mounted

brake disc

Brake

calipers

Brake Pads

Brake

Cylinder

AIR BRAKE SYSTEM ON LHB COACHES

Principle characteristics of brake system:

Application time: 3-5 SEC

Release time: 15-20 SEC

BRAKE INDICATORS

BRAKE APPLIED BRAKE RELEASED

QRV

HANDLE

QRV

DV

Pull QRV handle to release control

reservoir pressure. If brakes released

brake indicator will turn red to green.

SAB WABCO BRAKE CONTROL PANEL

FEED PIPE

ISOLATING

COCK

CDTS

ISOLATING

COCK

BOGIE-1

ISOLATING

COCK

BOGIE-2

ISOLATING

COCK

KNORR BREMSE BRAKE CONTROL PANEL

KNORR BREMSE BRAKE CONTROL PANEL

FEED PIPE

ISOLATING

COCK

CDTS

ISOLATING

COCK

BOGIE-1

ISOLATING

COCK

BOGIE-2

ISOLATING

COCK

SAB WABCO BRAKE CONTROL PANEL

FEED PIPE

ISOLATING

COCK

Turn the FP cock horizontal to

vertical to Isolate feed pipe supply

to aux. reservoir.

75 lt. AR

For CDTS 125 lt. AR for

brake system

AR

Drain cock

Open the drain cock of Aux. reservoir to

discharge the full pressure then close it.

The brake indicator will turn to green if

brake binding is due to pneumatic failure.

SAB WABCO BRAKE CONTROL PANEL

BOGIE-1

ISOLATING

COCK

BOGIE-2

ISOLATING

COCK

Isolate bogies by isolating both bogie cut out

cock, put FP in service and work the train.

The affected coach will run as piped vehicle.

FEED PIPE

ISOLATING

COCK

RESETING OF ACP

ACP RESETING PROCEDURE

SALIENT FEATURES &

WORKING PRINCIPLE OF

BMBS WAGON

GENERAL DESCRIPTION OF BMBS

The equipment consists of a transversely mounted

pneumatic actuator (Brake Cylinder) with a self-

contained, double acting slack adjuster, two brake

beams, two bell crank levers and interconnecting push

rods. The hand brake arrangement is available as a

mechanical model with two flexible hand brake cables.

The pneumatic actuator is 10” in diameter for application

on high friction brake shoe (K type) on casnub type

bogies. The system consists of a unique design with two

pneumatic actuators to deliver reliable braking

performance and is light in weight. It fits into any

standard IR casnub bogie and uses 58mm thick brake

shoes.

SALIENT FEATURES :-

1- Use of Two no’s of 10” Dia brake cylinders with automatic

load sensing device.

2- Use of 58 mm thick K type non asbestos composite

brake block.

3- Piston stroke of 56(+6,-0) mm in empty condition and 62

(+6,-0) mm in loaded condition is required to maintain.

4- Application of loads is at the ends the brake beam

instead of centre resulted no chances of bending of brake

beams.

5- Cylinder is with double acting slack adjustment feature

with constant piston stroke resulting is uniform brake

performances even as the brake shoes and wheels wears.

6- Total slack adjusting capacity is 500 mm including

brake block wear, wheel wear and all clearances.

7- All cylinders are equipped with an automatic piston

stroke indicator.

8- Replacement of the brake head is quickly and easy

by removal by only one pin.

9- Provision of mechanical hand brake system with the

use of two no’s stainless hand brake cables pulled

through standard hand brake rigging.

10- Easy fitment of bogie mounted cylinder on any

standard bogies without making any modifications.

ADVANTAGES OF BMBS OVER CONVENTIONAL

BRAKE SYSTEM

1-SAB is eliminated providing in built slack adjuster to

take up slack automatically.

2- Brake Rigging completely eliminated.

3- Wt of BK system Reduced approx: 300 Kg resulting

more carrying capacity.

4- E/L system Modified to Automatic Load sensing hence

there is no L/E handle.

5- Mechanical efficiency ( Brake percentage) Increased

to 47.6% ( was 43.8% in case of BOXN)

6- Push Rod of conventional type eliminated BK rigging

eliminated so there was a low chance of hanging

parts in Train.

7- Braking Distance decreased.

8- Wheel wear is Reduced due to use of K-Type 58 mm

thick composite BK Block.

9- Speed of Train Increased due to better control.

10- Reliability of BK system is increased.

11- Low Maintenance Cost.

12- No need of Detachment of wagons in en route when

BK pipe Damage.

13- Cylinder is mounted parallel to the brake beam and

transfer forces through the bell cranks.

14- Improves the efficiency and alignments of the

braking forces with the wheels which reduced the

wear of shoes and wheels.

15- Use of pressure regulated load sensing device,

installed between body and bogie under frame act on

15 psi to maintain normal sensor arm travel of 95 mm.

16- Use of single stage distributor valve (conventional

type).

17- Use of Two bell crank levers and two Inter

connecting Push rods, to transmit braking force from

bk cyl. to wheel through primary and secondary brake

beams.

Brake cylinder with double acting

slack adjustment feature.

DV in service

Piston stroke

indicator

When BP reduced, piston moves outward

and the indicator comes out from the BC.

DV in isolated condition and manually

Released…

Piston moves inside

and the indicator also moves inside.

APM (EL-60 Valve)

Automatically changes the BC pressure, 3.8kg/cm2 /

2.2kg/cm2 depending upon loaded / empty

condition. Installed between Distributor Valve and

Brake Cylinder. Physical contact of lever with side

frame only during braking.

Mounted on under frame, takes Deflection

of Bolster taken against side frame.

Individual bogie can be isolated by isolating the

corresponding bogie COC.

Normal position

of bogie COC

Individual bogie can be isolated by isolating the

corresponding bogie COC.

Isolated position

of bogie COC

During single pipe operation the FP can be

isolated by FP COC.

Isolated position

of FP COC

DV

Provision of mechanical hand brake

system with the use of two numbers

stainless hand brake cables pulled

through standard hand brake rigging in

one trolley only.

Mechanical arrangement for

Hand brake.

DV

To apply hand brake rotate the wheel

towards DV. (on either side)

As an indication the piston stroke

indicator will comes out.

DV

To release hand brake rotate the wheel

opposite to DV. (on either side)

As an indication the piston stroke

indicator will go inside.

To ensure the hand brake application

check the brake blocks are griping on

the wheel of corresponding trolley .