Kingston

Kingston 234 vertical in-tank check valves and 226 vertical in-line check valves

Coverage 1/4"–1 1/4" NPT, in-tank and in-line styles, up to 225°F

Vertical compressor tank and line check valves in a range of inlet/outlet thread combinations.

KNG-Series ASME safety relief valves (e.g. KNG560, KNG570, KNG740 side-outlet)

Coverage Receiver-mounted ASME relief valves: brass body (standard compressed-air service), stainless body (wash-down / corrosive / food-zone service), carbon steel for higher-pressure service. Connection sizes 1/2 in–3 in. Air set pressures to approximately 300 PSI on industrial-air models. Side-outlet and standard-outlet configurations available across the KNG range. Steam-rated and higher-pressure variants exist for non-air service.

Kingston's KNG-Series is the receiver-mounted ASME relief line in the SPC portfolio — the valve sized to the air receiver it protects. The series comes in 1/2 in through 3 in connections in brass, carbon steel, and stainless-steel bodies; brass is the standard for compressed-air service and stainless is specified for wash-down or corrosive environments. Air-service set pressures run up to roughly 300 PSI on the industrial-air models, which covers standard receiver MAWP ranges. KNG valves are ASME and National Board certified (Section VIII for unfired pressure vessels) and most carry a manual test lever for the annual lift test. Relieving capacity is published per orifice and set pressure: the KNG740-748 receiver-protection range spans six orifice letters — D (.126 in²), E (.217 in²), F (.353 in²), G (.554 in²), H (.923 in²), and J (1.418 in²) — and air SCFM capacity (ASME Section VIII) scales with both. At a 100 PSI set pressure the orifices deliver 253 / 436 / 708 / 1112 / 1852 / 2846 SCFM respectively; at 200 PSI, 476 / 820 / 1333 / 2093 / 3487 / 5356 SCFM; and at the 300 PSI air maximum, 699 / 1204 / 1958 / 3073 / 5121 / 7867 SCFM. Capacities are rated at 3 PSI or 10% over set pressure (whichever is greater). Per the Controls and Components 2026 Catalog (p.84-89), Kingston also offers a hard-seat high-flow safety relief valve line (118CSS series) plus additional Kingston relief valve series — 1/4"–1/2"+ NPT, rated up to 400°F, for ASME code applications to 300 PSI, with a hard-seat design for higher-temperature service on pumps, intercoolers, and aftercoolers; precision-machined brass body, stainless ball, pull-ring test.

Why Kingston here Kingston is the receiver-protection standard — a deep ASME-certified range that covers the 1/2 in–3 in receiver outlet ports and the set-pressure span of standard industrial air receivers, with brass and stainless body options for clean and corrosive service. It pairs naturally with the air-receiver category: every ASME receiver needs a code-stamped relief valve, and Kingston's published National Board certification gives the customer the documentation an inspector asks for. Where the application is a receiver-mounted port rather than a compressor-head connection, Kingston is the brand to promote.