Valve cage

A valve cage is a component of a valve that surrounds and supports the valve’s movable parts, such as the valve plug and stem. The valve cage helps to guide the valve plug and stem, ensuring that they move smoothly and precisely. It also helps to prevent damage to the valve body or other components.

The STP valve cage is made of cobalt alloy. This type of valve cage is often used in high-temperature, high-pressure, and corrosive environments where other materials would quickly degrade. STP valve cages are commonly found in applications such as steam turbines, gas turbines, and chemical processing plants.

STP is a brand name for cobalt-chromium alloys known for their exceptional wear resistance, high-temperature performance, and corrosion resistance. STP alloys are often used in applications requiring extreme resistance, such as aerospace and energy industries.

CObalt Alloy Chemical Composition

• 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 19  C: 1.5-2.0%, Mn: ≤1.0%, Si: ≤1.0%, Cr: 29.5～32.5%, Ni: ≤3.0%, Mo: -,  W: 9.5～11.5%, 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%