Manual Hold-Open Device with Limit Switches | SLB

Manual Hold-Open Device with Limit Switches

Manual valve operation in absence of control pressure

Schlumberger Oilfield Services

Cameron's manual hold-open device is designed for use with actuated gate valves sized 3 in and smaller in diameter with internal valve pressure up to 10,000 psi.

This hold-open device is used to manually operate the valve when control pressure is not available. The device threads directly to the top of the actuator. Rotating the handwheelproduces enough torque to overcome the actuator spring force and mechanically open the valve.

A hydraulic boostershould be used on high-pressure valves or any instance where the surface safety valve (SSV) must be manually opened and the maximum torque of this device is exceeded. This is to be used as a hold-open device only.

Compact, simple design

The space-saving design incorporates both the manual hold-open device and limit switches in one assembly, significantly reducing the overall length. The device is easy to install or remove by simple hand rotation on top of the actuator threaded boss. The upper and lower limit switches are easily and accurately adjusted by external jam nuts, thus eliminating trial and error settings.

Specifications
Manual Hold-Open Device
Service All applications
Max. torque, lbf.ft 195
Revolutions per in 5
Product weight, lbm [kg] 21 [9.5]
Shipping weight, lbm [kg] 25 [11.4]
Limit Switch Assembly
Manufacturer General equipment GO switch
Model Series 70, Model 75
Conduit outlet, in NPT 1/2 to 14
Type Single pole, double throw (SPDT)
Outlet position Bottom of enclosure
Certification British Approval Service for Electrical Equipment in Flammable Atmospheres (BESEEFA) and European Committee for Electrotechnical Standardization (CENELEC)
Manual Hold-Open Device with Limit Switches