Word forms: (regular plural) valve seats
(Automotive engineering: Vehicle components, Engine, transmission, and exhaust) The valve seat is the ring-shaped surface with which a poppet valve closes. ▶ valve
⇒ A valve seat is the part of the cylinder head that mates with the valve face. ⇒ Valve seat recession occurs when valve seats wear and the valve sink recedes into the cylinder
head. ⇒ Even when the valve is opening and shutting 12 times a second, its contact speed with
the valve seat can be as low as 0.1 meters per second.
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