Fuel hoses and pipes
Hose and pipe types
Rubber type hose
Various types available. When used for automotive applications it should comply with the relevant DIN 73379, ISO 19013 or SAE J 30 standard.
DIN 73379 includes
- type A
- type B
- type C
- type E
SAE J 30 includes
- SAE 30R6 - standard low pressure fuel hose
- SAE 30R7 - standard low pressure fuel hose
- SAE 30R9 - reinforced to handle higher pressures up to 180 psi and resist more aggressive fuels including alcohols, alcohol fuel blends, and biodiesel.
- SAE 30R10 - for applications where the hose will be submerged in the fuel - in tank.
- SAE 30R11
- SAE 30R12
Nylon pipe
Nylon pipe is often used in automotive applications. Where used in automotive aplications it should comply with DIN 73378.
Material compatibility
Care must be taken over the material compatibility of the fuel pipes and hoses and fuels to be utilised
Fuel pipe and hose diameter
The fuel system pipe and hose work has to be sized to give a sufficient flow of fuel to the engine without excessive suction being created in the suction side of the fuel supply system. Excessive suction will cause air to be drawn into the fuel system at hose joints, fuel filter gaskets (where operated in the suction side of the fuel supply system), etc.
The effects of restrictions in the fuel supply system are cumulative, a short tight restriction will not cause as much effect as a long pipe of slightly reduced diameter. The effect of doubling the diameter of a pipe or hose is to reduce the flow restriction by 16 times.
Poiseuille's Law which describes the effect of pipe diameter of flow
Clear fuel pipe and hose
Introducing sections of clear hose or pipe into the fuel system is useful for diagnosing fuel supply problems.