DISC BRAKE SYSTEM:

Axle Mounted Disc Brake System is being utilized in LHB type coaches equipped with FIAT types of bogies. In this types of brake system 2 nos. disc (640mm dia and 110 mm width) per axle are mounted. To actuate brake on each disc, Brake calipers (with brake pads of dia 35 mm) are mounted on bogie with 10’ dia brake cylinder.

Working principle:

The basic principle of axle mounted disc brake system is similar to conventional air brake system but the difference is only that the breaking occurred on discs instead of wheel trade in conventional system. As per Reduction of pressure in BP simultaneously pressure rises in brake cylinder and brake actuator actuates the brake pads which clasps with brake disc. As the discs are mounted on axle resulting wheels to stop.

MAIN COMPONENTS OF DISC BRAKE SYSTEM:
  • Control PanelBogie Equipments
  • Anti-skid system.
  • Flex ball cable arrangement ( for parking brakes )(Used only for Generator & SLR coaches).
CONTROL PANEL CONSISTS OF :
  • Distributor valve with suitable relay valves.
  • Control reservoir.
  • Air reservoirs – 2 nos. – 125 liters: for Air Brake- 75 liters: for Toilet System Stopcock – 2 nos. ( For Bogie isolation)
  • Isolating cock – 2 nos. ( For F.P. & Toilet circuits)
  • Filter (Dirt Collector) – 2 Nos.
  • Check valve.
  • Test fitting – 4 nos (B.P., F.P., B.C. & C.R.)
  • Pressure switch.
BOGIE EQUIPMENT CONSISTS OF :
  • Brake Disc.
  • Brake Caliper Unit comprising of Brake Cylinder.
  • Brake Caliper.
  • Brake Pads.
  • Indicators
  • Emergency Brake Accelerators with cock.
  • Emergency brake cable pull box.
  • Emergency brake valve.
  • Angle cock
  • Brake hose coupling (F.P. & B.P.).
ADVANTAGES:
  • Reduction in wheel wears resulting the increase in wheel life.
  • Fewer chances of wheel skidding due to break binding as WSP system is adopted.
  • The coefficient of friction is increased (i.e. 0.35) resulting from better braking.
  • Better controlling of the train due to the fitment of actuator valve which senses faster brake application and reduces the braking time in entire rake.(Braking distance is only 1200 m with 18 coaches and 160 kmph speed.)
  • The quick application of brake through ACP as the choke dia is increased from 08 mm to 19 mm.
  • Direct Isolation of the main component i.e. DV, CR, BC, AR etc is possible through the control panel.
  • Provision of standby cut off angle cock of BP and FP resulted enroute trouble can be tackled easily.
DISADVANTAGES:
  • Frequent replacement of Brake Disc due to cracks.
  • Critical maintenance due to fitment of electronic equipments.
  • Availability of spare as dump valve, accelerator valve, WSP system, microprocessor unit is critical.
  • Resetting of ACP is time taking in section as it is possible only with the same coach and compartment from where a chain is being pulled.