The MS API 6A check valve incorporates a metal-to-metal seal for high-pressure, high-temperature environments where elastomer seals cannot be used. Primary applications for the MS check valve are high-pressure mud choke manifolds and high pressure Christmas tree injection and kill lines. The MS Check Valve can be used with oil, gas, water, or drilling fluids and are available in all temperature and material classes as well as product specification levels (PSL) as specified in API 6A. It is available in standard pressure ratings from 3,000 to 20,000 psi and bore sizes from 1 13/16 to 7 1/16 in.


  • Metal-to-metal seals, offering advantages over elastomeric seals in applications where chemical and well fluids contact the sealing areas and extreme temperatures are a factor
  • Streamlined valve seat for low turbulence and improved body longevity
  • Forged steel construction leveraging Cameron quality
  • Uniformity through conformance to API 6A requirements for end-to-end measurements and available flanged connections, butt weld connections, or both
  • Low-maintenance operation—no lubricated parts and no routine maintenance required


MS Check Valves Standard Sizes and Pressure Ratings

Size, in 3,000 psi 5,000 psi 10,000 psi 15,000 psi 20,000 psi
1-13/16 N/A N/A X X X
2-1/16 X X X X N/A
2-9/16 X X X X X
3-1/16 X X X X X
4-1/16 X X X X N/A
5-1/8 X X X N/A N/A
7-1/16 X X X N/A N/A

Pressure-down rating may be required for service temperatures greater than 250 degF [121.1 degC].