What Is Air Brake Tubing?

Air brake tubing is a piping component used in commercial vehicle air brake systems. It is designed to transmit compressed air so that air pressure can be delivered to braking devices.

Heavy-duty vehicles such as trucks, trailers, buses, and articulated vehicles commonly use air brake systems as their primary braking method. These systems mainly consist of an air compressor, air reservoirs, control valves, braking devices, and connecting tubing.

Air brake straight tubing is typically installed in fixed chassis piping and is commonly manufactured from Polyamide (Nylon) to provide stable pressure resistance and reliable environmental adaptability.

Main Standards for Air Brake Tubing

Commercial vehicle air brake tubing is primarily classified by vehicle market into two major standard systems: DIN 74324 (Europe) and SAE J844 (North America).

Both standards define dimensional specifications, material performance, and related technical requirements for air brake tubing to ensure safe and stable operation of air brake systems during vehicle operation.

DIN 74324 (European Market)

DIN 74324 is a commercial vehicle air brake tubing standard developed in Germany and is mainly used in European trucks, buses, and trailers. Its dimensional specifications are based on the metric system.

SAE J844 (North American Market)

SAE J844 is an air brake tubing standard developed by the Society of Automotive Engineers and is mainly used in North American trucks and trailers.

This standard adopts the inch-based dimensional system and classifies tubing into Type A and Type B according to application conditions.

Comparison Between DIN 74324 and SAE J844

DOT FMVSS 106 and Air Brake Systems

In the North American market, commercial vehicle air brake systems are typically required to comply with DOT FMVSS 106.

DOT FMVSS 106 is a vehicle brake system safety regulation that mainly defines performance, testing, and identification requirements for brake hoses and related components. Air brake tubing compliant with SAE J844 may be used in vehicle brake systems that meet DOT FMVSS 106 requirements.

Further Reading

→ DOT Air Brake Fittings

→ Commercial Vehicle Brake Coiled Tubing

→ DOT Brake Tubing Applications in Commercial Vehicle Systems