Presented By,
Mathew scaria

---

[attachment=11021]
ENGINE RETARDERS
WHAT IS AN ENGINE RETARDER…….?
 ER is a supplementary brake system.
 It receives the vehicle braking system of some of the light duty braking.
NEED FOR ENGINE REARDER
 To maintain a consistent coefficient of friction between braking component.
 To increase braking efficiency.
 To decrease brake fade.
RETARDING PRINCIPLE
 Retarders means any components or system that effect braking action or slows motions.
 Working principle is the conversion of kinetic energy (that of vehicle motion) firstly into potential energy of compressed air and then released into the exhaust system as heat.
PRINCIPLES OF OPERATIONS
 Engine brake uses there distinct operation principles
1. Internal engine compression brake
2. External engine compression brake
3. Hydraulic engine brake
INTERNAL ENGINE COMPRESSION BRAKES
 It uses MEP(Mean Effective Pressure) equation to change the role of the engine.
 It compresses the air charge on the compression stroke ,then just as the power stroke is about to take place ,it releases the cylinder pressure by opening the exhaust valves.
 Wheel rotation (kinetic energy) is converted to compress the air(potential energy) and is dumped to exhaust.
INTERNAL COMPRESSION BRAKE (JAKE BRAKE)
EXTERNAL ENGINE COMPRESSION BRAKES (EXHAUST BRAKES)
 Consists of housing attached to turbine housing discharge in a turbo charger.
 Exhaust brake housing is a valve when attached ,chokes off the exhaust discharge.
 Restricting exhaust gas flow in this way once again reverses the role of the engine.
EXHAUST BRAKE ( williams brake)
INTERNAL BRAKES vs EXTERNAL BRAKES
 In internal engine compression brake ,the effective pumping stroke is the compression stroke.
 In exhaust brake ,the effective retarding stroke becomes exhaust stroke.
HYDRAULIC ENGINE BRAKES (Brake saver)
 Brake saver is a reversly operating torque converter.
 Brake saver rotor is coupled directly to rear of crankshaft inside the Brake saver housing.
HYDRAULIC BRAKE (brake saver)
BRAKE SAVER OPERATION
 Brake saver off : Housing is not charged with pressurized engine oil ,and rotor can turn freely inside the housing.
 Brake saver on : Housing is charged with pressurized engine oil ,rotor’s ability to turn is modulated by fluid resistance and the pockets. producing retarding effect.