VC-150 Swing Check Valve

A bolted cover swing check valve sized on actual flow rather than line size, so the disc sits fully open instead of fluttering against the stop.

Sized against the actual flow so the disc holds fully open instead of fluttering

Bolted cover gives access to disc and hinge without removing the valve

Renewable hinge pin bushes rather than a pin running in the body

Optional lever and weight or lever and spring for pump discharge lines

Specifications

Design standard: API 6D / BS 1868 / ASME B16.34
Nominal size: DN50 – DN600 (NPS 2 – 24)
Pressure class: Class 150 / 300
Body material: ASTM A216 WCB, A351 CF8M, A352 LCB
Trim material: 13Cr or hardfaced seat and disc facings
End connection: Raised face flange to ASME B16.5, butt weld to B16.25
Operating temperature: -29 °C to +425 °C (WCB body)
Face-to-face: ASME B16.10
Mounting position: Horizontal, or vertical with upward flow
Test practice: Shell and seat to API 598

Product detail

Check valves fail more often from being oversized than from being worn out. A swing check needs enough flow to hold the disc firmly against the backstop; below that velocity the disc hovers, the hinge pin wears and the valve starts to slam on every reversal. The VC-150 is supplied against the flow you actually have, which sometimes means a smaller valve with reducers rather than a line size valve.

Construction

Bolted cover with a spiral wound gasket, so the disc and hinge can be inspected without cutting the valve out of the line. The hinge pin runs in renewable bushes, and the disc is free to rotate slightly so the seating contact does not always land in the same place.

Slam and damping

On pump discharge lines with a long column of liquid behind the valve, a plain swing disc can close hard enough to shock the line. An external lever and weight or a lever and spring is available to bring the disc closer to its seat before flow reverses. If reverse flow develops quickly, a dual plate or axial nozzle check is a better fit and we will say so.

Orientation

Horizontal lines, or vertical lines with upward flow only. Fitted on a downward flow line the disc will not close under its own weight. The arrow on the body is the flow direction, and it is worth checking before the flanges are torqued.