How compressed-air valves for trucks units and trailers work
The market for new and reconditioned components to repair trucks and trailers has expanded greatly over the years. In this article we look at how air brake valves work and why they are essential for trucks.
Compressed-air brake valves for trucks:
Pneumatic braking systems use compressed air to control the devices for disposing of accumulated kinetic energy on vehicles over 3.5 T: they intervene during movement, transforming it into thermal energy to cause braking.
This is why air brake valves on trucks (tractor) and trailers become essential for regulating the air transfer in the circuit, which reaches the brakes themselves in a few seconds.
Compressed air is produced by the compressor, which is connected to the dryer via a pressure regulator. The dryer removes water vapour from the compressed air by discharging it into the atmosphere through the 4-circuit protection valve, which limits the pressure inside even if one of them fails.
Trucks and trailers: how pedal-controlled braking works
The foot resting on the brake pedal actuates the tractor’s air distributor from the reservoirs through the ABS control solenoid valve to the automatic brake corrector and finally to the Tristop Cylinder service brake.
When the trailer is also present, its air distributor comes into play to allow the air to reach the automatic brake corrector and the ABS relay valve, passing through the release and adapter valve.
Braking management of the trailer is directly linked to the load: depending on the load, the system activates the adaptive air brake valve.
Truck parking and emergency brake
In the parking brake system, however, other air brake valves are involved: in this case, the air flows from the dedicated reservoir, to the holding valve, to the handbrake valve and the relay valve, and ends up in the pre-loaded spring of the Tristop Cylinders.
When the parking brake valve is activated, the Tristop springs are completely vented and therefore the trailer is braked with the flexible connecting hose.
But there is another indispensable component in the braking systems of trucks and trailers: this is the emergency brake, which is able to kick in promptly in the event of a failure of the service brake circuits.
Industrial brake valves: the most important ones
In the past, pneumatic brake systems were prone to blockages due to air leaks, but thanks to the evolution of mechanics, the modern brake valve system also assists in cases of pressure drops.
Here are the most important air brake valves:
- Pressure Control Valves – useful in cases of pressure drop
- Connecting Couplings – they join the tractor’s braking system with that of the trailer
- Protection Valves – indispensable in the presence of various circuits
- Trailer Servodistributor – adjusts the braking system
- Solenoid Valve – maintains pressure in the Brake Chamber
- Relay Valves – reduce braking duration and response threshold
- Leveling Valves – adjust the pressure in pneumatic suspension bellows according to the load
- Truck Servo Clutch – reduces activation force and makes driving comfortable
- Pressure Regulator – automatically regulates the pressure in the system by protecting pipes and valves from impurities
- Automatic Brake Corrector – adjusts braking force based on load
- Release Valves – open the braking system to move uncoupled trailers
- Pressure Relief Valves – limit the pressure to the pre-set value
- Brake Distributor – gradually supply and exhaust air from the Tractor Brake Chamber
- Bleed Valve – protects the system from condensation
GGN always offers guaranteed products and a complete line of air brake valves for trucks and trailers, thus offering customers both cost and efficiency advantages and reducing waiting times.
