Exhaust braking is the installation of a valve between the engine exhaust pipe outlet and the muffler intake pipe, when the exhaust brake does not work, the valve pad is in the open position, does not affect the normal operation of the engine, when the exhaust brake is active, the valve flap slot slowers, so that the engine in the exhaust travel, the exhaust gas due to the valve flap closed exhaust channel is compressed,
Increased exhaust back pressure for the engine to increase the engine pressure volume P-V. Currently reliable, technologically advanced and widely used are electromagnetic-air pressure-controlled or vacuum-controlled exhaust braking systems. Electromagnetic -air pressure controlled exhaust braking is mainly used in air brake vehicles with compressed air as energy.
The latter is vacuum-powered on hydraulic brake vehicles.
Characteristics of exhaust braking The size of the exhaust brake back pressure directly affects the effect of exhaust braking. The exhaust brake back pressure is related to the displacement, compression ratio and speed of the engine. The higher the exhaust brake back pressure and the greater the pump gas loss, the better the braking effect, the greater the reduction speed of the exhaust brake. The size of the exhaust brake reduction speed is proportional to the braking torque, transmission and rear axle speed ratio of the engine output, and inversely proportional to the total weight of the vehicle, the rolling radius of the tyre, and the transmission efficiency.