API Standard Flange Swing Check Valve

AFlange Swing Check Valve is a specific and widely used type of Check Valve. Its primary function is to automatically prevent the reverse flow of media in a pipeline system, allowing flow in only one direction.Its core mechanism features a disc (or flap) that swings on a hinge or trunnion. Under forward flow pressure, the disc swings open; when the flow stops or reverses, the disc swings closed by gravity and backflow pressure to form a seal.

As a professional manufacturer with integrated production control and a rigorous quality system, Wenzhou Chenyu supplies high-quality Flange Swing Check Valves. These valves are manufactured to international standards (such as API, ASME) using various material grades, ensuring reliable performance for demanding applications in industries like petrochemicals, power generation, and metallurgy.

Main Specification of the Product

Flange Swing Check Valve Applications

• Oil & Gas: Used in transmission pipelines, pump discharges, and compressor stations.

• Chemical & Petrochemical Plants: Protects pumps and reactors in lines carrying corrosive media.

• Power Generation: Installed in boiler feedwater, cooling water, and steam lines.

• Metallurgy & Heavy Industry: Provides reliable unidirectional flow for systems with high-temperature water, thermal oil, and other industrial fluids.

Main Advantage of Flange Swing Check Valve

1. High Pressure & Large Size Capability: The extensive size (2" to 48") and pressure (150 to 2500 LB) range meets requirements from process lines to main transmission pipelines.

2. Reliable High-Pressure Sealing: The 2500 LB rating, combined with the pressure self-sealing bonnet option, ensures superior sealing integrity under extreme pressure.

3. Durability & Low Maintenance: Robust construction and proven material combinations ensure a long service life with minimal maintenance, even with frequent cycling and pressure fluctuations.

4. Broad Service Compatibility: The material spectrum, from carbon steel to duplex, allows it to handle water, steam, oil, corrosive chemicals, and cryogenic media.

5. Fully Certified Reliability & Interchangeability: Full compliance with international standards for design, face-to-face dimensions, end connections, and testing (API 598) guarantees reliable performance and global system interchangeability.

Technical Specifications

Main dimension:CALSS 150LB

CALSS 300LB

CLASS 600LB

CLASS 900LB

Structure & Design of Flange Swing Check Valve

• Body & Ends: Features Flanged (FLG) or Butt Weld (BW) connections, suitable for systems from standard to ultra-high pressure (up to 2500 LB).

• Disc & Arm: Employs a classic swing check design where the disc pivots on an external hinge pin for swift opening and closing.

• Bonnet Types: Available with a Pressure Self-sealing Bonnet (ideal for high pressure, where seal improves with internal pressure) or a Bolted Bonnet, catering to different pressure classes and maintenance needs.

• Design Compliance: Manufactured in strict accordance with ASME B16.34 / BS1868 to ensure structural integrity.

Flange Swing Check Valve Material Selection

• Carbon Steel: WCB, WCC (general service), LCB, LCC (low-temperature service).

• Cast Iron: GG25 (Gray Cast Iron), GGG40 (Ductile Iron) for low-pressure, non-corrosive media.

• Stainless Steel & Special Alloys:

  • CF8 (304), CF8M (316): For a wide range of corrosive chemicals.

  • 2205 & Duplex Stainless Steel: Offers excellent resistance to chloride stress corrosion cracking, suitable for seawater and harsh chemical environments.