Specs & Brochures



Crosby HSL Safety Valve

Crosby Style HSL is a full nozzle reaction type safety valve designed for saturated and superheated steam service.

The design is suitable for set pressures to 725 psig [50 barg] and temperatures to
1000°F [538°C], with high capacities, two choices of inlet flange ratings and a simplicity of design to facilitate ease of maintenance.

The Crosby HSL valve design meets the requirements of ASME Code Section I, Power Boilers and relieving capacities are certified by the National Board of Boiler & Pressure Vessel Inspectors. Style HSL may also be used in steam service applications covered by ASME Code Section VIII requirements.

Crosby HSL Safety Valve Features & Benefits:

  • FLEXI-DISC® seat design: recessed for pressure and temperature equalization. Ensures a flat and tight seal.
  • High coefficient of discharge: results in the most economical valve selection.
  • Replaceable full nozzle design: facilitates ease of maintenance and longer service life. Nozzle removal requires no special tools.
  • Seat tightness: FLEXI-DISC seat capable of containing system pressure at 94% of set pressure. Standard seat tightness testing conducted at 93% of set pressure.
  • Single bonnet design: allows set pressure changes without the need to change-out any components besides the spring.
  • Back pressure limit: 27.5% of set pressure

Crosby HSL Specifications:

Saturated and superheated steam service
Inlet sizes: 11/4" to 6" flanged
Inlet ratings: CL 300#, CL 600#
Outlet rating: CL 150#
Maximum set pressure: 725 psig [50 barg]
Temperatures to 1000°F [538°C]
Orifices: F through Q
Blowdown: 4%
Back pressure limit: 27.5% of set pressure
Capacity certification: ASME Boiler & Pressure Vessel Code Section I and VIII

Certification and type approvals

  • ASME Boiler and Pressure Vessel Code Section I and VIII
  • National Board of Boiler and Pressure Vessel Inspectors Capacity Certifications
  • Canadian Registration Number
  • Pressure Equipment Directive (97/27/EC) (ISO 4126-1) (CE)
  • China Manufacturing License (TS)

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