Valve seat

STP alloy valve seat is made from a cobalt-chromium alloy called STP, known for its excellent wear resistance, high-temperature strength, and corrosion resistance.

• STP 1  C: 2.2～2.8%, Mn: -, Si: ≤2.0%, Cr: 29.0～33.0%, Ni: ≤3.0%, Mo: ≤1.0%,  W: 11.0～14.0%, Co: Bal., Fe: ≤3%
• STP 3  C: 2.0～2.7%, Mn: ≤1.0%, Si: ≤1.0%, Cr: 29.0～33.0%, Ni: ≤3.0%, Mo: -,  W: 11.0～14.0%, Co: Bal., Fe: ≤3%
• STP 4  C: 0.8～1.3%, Mn: ≤1.0%, Si: ≤1.5%, Cr: 28.0～32.0%, Ni: ≤3.0%, Mo: ≤1.5%,  W: 12.5～15.5%, Co: Bal., Fe: ≤3%
• STP 6  C: 0.9～1.4%, Mn: ≤1.0%, Si: ≤1.5%, Cr: 27.0～31.0%, Ni: ≤3.0%, Mo: ≤1.5%,  W: 3.5～5.5%, Co: Bal., Fe: ≤3%
• STP 12  C: 1.1～1.7%, Mn: ≤1.0%, Si: ≤1.0%, Cr: 28.0～32.0%, Ni: ≤3.0%, Mo: -,  W: 7.0～9.5%, Co: Bal., Fe: ≤3%
• STP 20  C: 2.2～3.0%, Mn: -, Si: ≤2.0%, Cr: 25.0～29.0%, Ni: ≤3.0%, Mo: ≤1.0%,  W: 14.0～19.0%, Co: Bal., Fe: ≤3%

STP alloy valve seats are typically installed by welding them into the engine’s cylinder head, where they become a permanent part of the engine.

In an internal combustion engine, the valve seat is the surface with which the engine’s valves make contact when they close. The valve seat must be hard and wear-resistant to prevent excessive wear and ensure a tight seal between the valve and the seat. STP valve seats are often used in high-performance engines because they can withstand the high temperatures and stresses generated by the engine. STP valve seats are commonly used in racing engines, aircraft engines, and other high-performance applications where durability and reliability are crucial.