VALVE SEAL
Description
A valve stem seal (VSS) is the seal assembled in the engine head together with the valve guide, preventing the engine oil from flowing into the engine head combustor. Valve stem seals must be both leak-proof and permeable at the same time. The reason for this apparent contradiction is through controlled leakage. The valve stem seal allows a carefully defined amount of engine oil from the cylinderhead into the combustion chamber allowing a necessary lubrication of the rotating valve stem in the valve guide.
Application
None
Materials
None
TECHNICAL DATA
TECHNICAL DATA
| Temperature | None -30°C/+100°C |
| Pressure | None 30 MPa |
| Speed | None 1.0 m/s |
| Medias | None Mineral hydraulic oils |
MATERIALS
MATERIALS
NONE
Polyurethane is a material that has the elastic properties of rubber. The proportion in its composition (diisocyanate, polyol, chain extender) is determined by its properties. This material is characterised by a strong mechanical resistance, good wear resistance, high elastic modulus, good flexibility and a very good ozone and oxidation resistance.
| Chemical resistance | Pure aliphatic hydrocarbons (propane, butane) Mineral oils and greases Silicone oils and greases Water up to +50°C |
|---|---|
| Compatibility issue | Ketones, esters, ethers, alcohols and glycols Hot water, steam, alkalis, amines and acids |
| Temperature range | -30°C/+90°C -30°C / +110°C with our PUHT (short term peak at 150°C) |