Leader Check & Non-Return Valves

About the Leader check valves range

We hold the Leader agency directly. The Leader check valve range runs to 59 families, 8 mm to 950 mm, in 10 body materials.

A check valve is chosen by the way it closes, not by its bore. Swing patterns suit horizontal lines carrying clean water and close under gravity; lift and disc patterns close faster and cope with pulsating flow, at the cost of a higher pressure drop. Where a pump can reverse against a static head, closing speed is the number that matters.

The Leader range here is supplied in carbon steel WCB for steam and higher pressures, cast iron to IS 210 for larger bores on water duty, gunmetal to IS 318 LTB-2 for potable and general water service and forged carbon steel A105 on small-bore high-pressure lines, and 3 more. What the line carries, and how hot it runs, decide the body. Those two facts narrow the choice before bore, class or budget are considered at all.

Sizes span 8–25 mm, 32–50 mm, 65–100 mm, 125–200 mm and 250–950 mm. Across that range the construction changes more than once, so a size at the top of the range and one at the bottom are related products rather than the same product in two sizes.

End connections run to Flanged, Wafer and Screwed BSP (parallel). The connection has to be settled against the mating pipework before a size is ordered — a flanged valve and a screwed one are not interchangeable on an installed line.

The range is rated PN 16, Class 150, Class 300 and PN 25. Class is chosen against the duty, including any surge the line sees, rather than against the nominal system pressure alone.

Products in this range are built to API 594, BS 5154 and BS 1868 / API 6D. The standard is what a consultant writes into a specification, so it is worth quoting it on the enquiry.

Test certificates are available against the order where the product carries them. It is worth confirming the requirement before the order is placed rather than at delivery.

Send the line's orientation and whether the pump can reverse against a static head with the schedule when you enquire about check valves. Sizes and quantities alone leave the one question open that decides which valve is actually correct.

Prices are ex-GST list. Where a size is not shown, ask — the range extends beyond what is held as standard.