High Pressure Gate Valve Made of Cast Steel

1. Basic Standards and Specifications
International standards:

● API 600 (steel gate valves for the oil and gas industry)

● ASME B16.34 (Nominal Pressure-Temperature Valve)

● ISO 10434 (bolted steel gate valves for oil and gas industry)

National Standard (GB):

● GB/T 12234 (Steel gate valves for oil and gas industry)

● JB/T 3595 (Specification for Power Plant Valves)

Russian Standard (GOST):

● GOST 3706-93 (general specifications for gate valves)

● GOST 9544-2015 (Valve Seal Standard)

2. Construction and material
(1) Valve body and main components
Valve Body Material:

● Carbon steel (WCB, WCC, A216) - suitable for general high-pressure working conditions

● Alloy steel (WC6, WC9, C5, C12A) – resistant to high temperatures and high pressures (e.g., boiler systems of power plants)

● Stainless steel (CF8, CF8M, CF3, CF3M) – resistant to corrosive environments (chemical, marine)

Gate Type:

● One-piece wedge – suitable for high temperature and high pressure, strong anti-deformation ability

● Flexible wedge – slightly deformable, better sealing

● Split wedge – suitable for media prone to scale or containing particles

(2) Seals and Gaskets
Valve seat seal:

● Metal solid seal (Stellite 6 coating) – resistant to high temperature and erosion

● Soft seal (PTFE, rubber) – suitable for low temperature or clean environments

Valve stem gasket:

● Graphite braided packing (suitable for high temperature and high pressure)

● PTFE seal (suitable for corrosive environments)

● Bellows seal (used for high-risk environments, zero leakage requirement)

3. Main characteristics
✅ High Pressure Withstand Ability: Generally suitable for 150~2500 (PN16~PN420) classes, some ultra high pressure models can reach 10,000 psi (about 690 bar).
✅ High Temperature Resistance: Depending on the material, it can withstand -29°C~593°C (stainless steel can reach 800°C).
✅ Bi-directional seal: Gate valves usually withstand bi-directional pressure and are suitable for pipelines with bi-directional fluid flow.
✅ Low flow resistance: Full bore design to reduce pressure loss.
✅ Long Service Life: High quality cast steel hardened sealing surface, suitable for heavy duty applications.