Piston valves

3 models in this family

Review the listed models and configurations in this family, then select one for a quotation request.

Selected model

Standard piston valve

Request this configuration Chat on WhatsApp

Standard piston valve with a cast-steel body, forged-steel bonnet and stainless-steel piston. The piston travels between reinforced-graphite sealing rings: the lower ring provides in-line sealing, while the upper ring provides external sealing and seals the body-to-bonnet region. Spring washers beneath the bonnet fasteners maintain compression on the rings. Handwheel operation, a lantern bush and replaceable sealing components form part of the design. The carbon-steel series includes NPT, socket-weld and flanged arrangements.

021 7773 8993 0993 809 9391

Selected model specifications

Body	Cast steel
Bonnet	Forged steel
Piston	Stainless steel
Main sealing rings	KXGT reinforced graphite
Seal loading	Spring washers at bonnet fasteners
Nominal size range	DN 6–50 / NPS 1/4–2
Connection arrangements	NPT / SW / Flanged
Carbon-steel series ratings	ISO PN20 / Class150; ISO PN40; ISO PN50 / Class300
Operation	Manual handwheel

Models and configurations

Select a configuration. The family image changes only when the model has a distinct illustration.

Standard piston valveBody: Cast steel · Bonnet: Forged steel · Piston: Stainless steel · Main sealing rings: KXGT reinforced graphite · Seal loading: Spring washers at bonnet fasteners · Nominal size range: DN 6–50 / NPS 1/4–2 · Connection arrangements: NPT / SW / Flanged · Carbon-steel series ratings: ISO PN20 / Class150; ISO PN40; ISO PN50 / Class300 · Operation: Manual handwheelStandard piston valve with a cast-steel body, forged-steel bonnet and stainless-steel piston. The piston travels between reinforced-graphite sealing rings: the lower ring provides in-line sealing, while the upper ring provides external sealing and seals the body-to-bonnet region. Spring washers beneath the bonnet fasteners maintain compression on the rings. Handwheel operation, a lantern bush and replaceable sealing components form part of the design. The carbon-steel series includes NPT, socket-weld and flanged arrangements.

Pressure-balanced piston valvePiston arrangement: Pressure balanced · Nominal size range: DN 65–200 / NPS 2 1/2–8 · Bonnet: Cast steel · Sealing rings: Graphite and reinforced graphite · Guidance assembly: Guide stem, lantern bush and flow-guidance cone · Seal loading: Spring washers · Stuffing arrangement: Screwed · Operation: Manual handwheel and stem nutPressure-balanced piston valve for the larger-size arrangement within the piston-valve family. Its internals include a piston, guide stem, flow-guidance cone, and graphite and reinforced-graphite ring assemblies. A cast-steel bonnet is secured by bolted fasteners and spring washers. Handwheel operation is transmitted through the stem and stem nut. A screwed stuffing arrangement, lantern bush, pressure rings and supporting components guide the piston and sealing assembly.

Double-sealing piston valveSealing mechanism: Ring-to-piston contact plus metal cone-to-cone contact · Body and bonnet: Cast steel · Piston-mounted ring: High-temperature-resistant, plastically deformable · Additional rings: Reinforced graphite · Nominal size range: DN 15–50 / NPS 1/2–2 · Pressure designation: ISO PN40 / PN50 · End connections: Socket-weld or flanged · Service: Saturated steam and steam/condensate mixtures · Service pressure limit: 42 barDouble-sealing piston valve for saturated steam and steam/condensate mixtures. It forms two in-line sealing contacts: contact between the ring and piston, and a metal cone-to-cone contact between the disc and seat. The piston-mounted ring is a high-temperature-resistant, plastically deformable type; reinforced-graphite rings are also included. The body and bonnet are cast steel. This arrangement covers DN15 to DN50, ISO PN40 and PN50, with socket-weld or flanged ends, and a stated pressure limit of 42 bar for the steam/condensate service.