Automotive hoses are an essential component of every vehicle. On average, each vehicle is fitted with approximately 20 metres of hose, which is vital for the smooth and efficient operation of various automotive systems. These hoses are highly flexible and are used to convey essential fluids and gases, ensuring the critical functions of the engine, fuel supply, braking and power steering systems.

The types of automotive hoses vary depending on the specific vehicle component. Automotive hoses are designed to withstand the harsh automotive environment and provide reliable transport of fluids and gases to ensure optimum performance and safety. 

Today, we’ll take an in-depth look at the various types of automotive hoses and how they are categorised.

Classified by operating environment and medium

Depending on their operating environment and function, automotive hoses can be categorised as follows: 

Fuel line:

A hose used to connect the engine to the fuel tank, fuel pump and fuel filter.

Hydraulic hoses:

Used for hydraulic hoses, brake fluid hoses and the like in automotive hydraulic systems.

Air conditioning pipes:

Hoses used to connect the refrigerant, condenser, evaporator, compressor and other components in a vehicle’s air-conditioning system.

Water pipes:

Hoses used to connect components such as the water tank, water pump, radiator and thermostat in a vehicle’s cooling system.

Exhaust pipe:

A flexible hose used to connect components such as the intake manifold, air filter and throttle body in a vehicle’s intake system.

Classification by functional system

Automotive hoses are key components of various vehicle subsystems. By system, these primarily include: hoses for the vehicle’s cooling and heating systems, fuel systems, steering systems, braking systems, air conditioning systems, intake systems, gearbox oil cooling systems, and body accessory systems.

Hoses for automotive cooling and heating systems

Hoses for automotive cooling and heating systems primarily comprise the pipework connecting the car’s radiator, heater blower, auxiliary radiator and radiator; they are generally made from synthetic rubber that is resistant to high temperatures and antifreeze [primarily ethylene propylene diene monomer (EPDM) rubber], and the working medium is antifreeze.

Hoses for automotive fuel systems

Fuel system hoses in motor vehicles comprise the connecting lines between the fuel pump, the fuel filter, the engine and the exhaust after-treatment system. They are primarily constructed from synthetic rubber resistant to fuel permeation, composite resins or copolymers of synthetic rubber and resin, combined with a reinforcing layer; the main working medium is petrol or diesel.

Automotive steering system hoses

The hoses in a vehicle’s steering system comprise the connecting lines between the reservoir (oil tank), the power steering pump and the power steering unit. They are generally constructed from synthetic rubber that is resistant to high temperatures and flexing, and feature a high-pressure-resistant reinforcement layer. Both ends of the hoses are connected to carbon steel or stainless steel metal pipes, and the working fluid is hydraulic oil (power steering fluid).

Automotive Brake System Hoses

Automotive braking system hoses primarily comprise the connecting lines for the clutch master cylinder, vacuum booster, brake calipers and air compressor. They are generally constructed from olefin-based synthetic rubber, nylon resin and carbon steel tubing fitted with metal fittings. The working medium is primarily brake fluid or compressed air. Currently, the main grades of brake fluid are DOT 3 or DOT 4.

Hoses for automotive air-conditioning systems

Hoses in automotive air-conditioning systems primarily comprise the piping connecting the air-conditioning evaporator, condenser and desiccant canister. These are generally made of pure rubber hoses or rubber/resin composite hoses, and are sometimes combined with carbon steel or light alloy pipework to form assemblies; the primary working medium is air-conditioning refrigerant. Currently, the mainstream refrigerants include 1,1,1,2-tetrafluoroethane (R134a), tetrafluoropropylene (R1234YF) and carbon dioxide, amongst others.

Automotive intake system hoses

Hoses in a vehicle’s intake system primarily comprise the connecting lines between the air filter, turbocharger, intercooler, engine and crankcase ventilation system. Operating temperatures vary considerably between hoses in different locations. The working media are high-temperature, medium-pressure mixtures of fuel vapour and air, and air.

Hoses for the automotive gearbox oil cooling system

Hoses in automotive oil-cooling systems primarily serve as connecting lines between automatic gearboxes and gearbox coolers; the main working medium is high-temperature, high-pressure gearbox lubricant.

Hoses for automotive body accessory systems

Common hoses used in vehicle body accessory systems include front and rear windscreen wiper washer hoses, which are generally made of nylon or EPDM without a reinforcing layer and are used to convey windscreen washer fluid.