Swing check valve with pressure seal - UNIFLOW Fig. 31 | Comeval

Comeval UNIFLOW Fig. 31 – Swing Check Valve, Pressure Seal

The Comeval UNIFLOW Fig. 31 is a pressure seal swing check valve designed for high-pressure pipelines. The disc opens with flow and closes automatically when the differential pressure drops or reverses. No actuator is required. Metal-to-metal sealing is standard, with a pivoted disc construction suitable for steam, gases, compressed air, and industrial networks with high pressure ratings.

Versions and Pressure Classes

Product range covers DN50–DN900 / 2"–36" and PN16–PN420 / ANSI Class 150–2500. Technical drawings for Fig. 31 show Class 1500, DN50–DN400 variants, with RF, RTJ, or BW end connections.

Construction Materials

Main metallurgy options:

• Stainless cast: CF8, CF8M, CF3, CF3M
• Carbon / low-temp steel: A216 WCB, A352 LCB
• Alloy steels: WC1, WC6, WC9, C5, C12

Seats and discs are supplied with hard facing. Gaskets are stainless steel with graphite for relevant versions.

Standards

Design per API 6D / BS 1868, face-to-face per ASME B16.10, flanges per ASME B16.5, welding ends per ASME B16.25, and testing per API 598. Product certifications include PED Module H and EAC.

Application Guidance

Suitable for high-pressure steam, condensate, boiler feedwater, gases, compressed air, hydrocarbons, and thermal fluids. Final selection depends on pressure-temperature rating, corrosion, trim, and seat leakage requirements.

FAQ

When is a pressure seal swing check selected?
For high pressure classes where swing check with metal seat and pressure seal construction is required.

What is needed before ordering?
Specify class, DN/NPS, RF/RTJ/BW ends, body material, trim, temperature, media, and minimum flow for stable disc opening.