needle seal

[marcoabelius]

I'm trying to improve a fluid application gun. The sealing I'm using for the needle (diameter 2,5mm) starts to leak after about 10 million strokes. It is a spring energized seal.
Does anyone know seals which have a longer lifetime? I have a fluid pressure up to 80 bar and a temperature of max. 200°C.

 

[DPeddle]

This is a tough question to answer without knowing the specifics of what design and materials you are using today. There are good FKM elastomers that will take alot of abuse at up to 200°C, but its hard to make any material or design recommendations beyond that.

 

[marcoabelius]

It is a spring energized seal with a sharp sealing lip. Material is a PFTE-compound.
Our supplier has recommended a special design with two or three sealing-lips, which will hopefully have a longer operation time!