Internal expanding sealing components (Type NM)

Price :

Performance and Purpose:

Comprised of sealing ring, fan-shaped supporting blocks and fan-shaped angles, this is mainly used by hydrostatic testing machines for pressure testing of steel pipes. As it is designed to test steel pipe from its inner diameter, when testing, the sealing ring will expand to enclose the pipe inner diameter to achieve the purpose of sealing. Its test head is smaller than type D or C and production cost is lower as well. It is applicable to the pressure testing of casings, tubings, natural gas pipes and other steel pipes.



  1. Lip Optimization: under peripheral pressure, the lip and groove surface fit more closely, and the higher the pressure, the better the lip sealing.
  2. The fan-shaped supporters, in the premise of increasing the strength of the sealing ring, can shrink and expand in radial direction with the sealing ring.

Working conditions:

Compliant for use with several standards about hydraulic testing requirements including API 5CT-2018, ISO11960:2011 Petroleum and natural gas industries—Steel pipes for casing or tubing, GB/T9711.1-2011, GB/T9711.2-2011; GB8163 – 2008 for seamless steel tubes; GB/T3092-2008 for welded steel pipes.

Working pressure: ≤ 60 M Pa

Working temperature: -20℃~+80℃

Working medium: water, emulsion, hydraulic oil

Material: Polyurethane