Safety Shut-Off Valves
This Pressure Protection System is designed to protect equipment downstream of a pressure reducing station in a gas distribution system. It consists of a trunnion mounted ball valve complete with actuator and control system supplied in a self-contained and compact unit. It is installed in the pipeline, upstream of the pressure reducing station. If there is an excessive rise (PP-A Type) / rise or fall (PP-B Type) of pressure downstream of the station due to an equipment or operational malfunction, it will react by shutting off the supply of high pressure gas.
Ball Valve
- Trunnion mounted
- Two piece or three piece construction
- Double block and bleed in open and closed position
- Antistatic device
- Sealant injection system
Actuator
- Double acting Scotch Yoke
- Yoke design optimized to give increased torque output in breakout/reseat position
- Low friction self-lubricating PTFE piston seals as standard
- Nickel plated steel alloy drive shaft and hardened steel alloy yoke assembly
- All bearing surfaces lubricated for life
- Lapped and anodized cylinder bores
- Acetylic resin drive shaft bearings
- Anodized actuator body to prevent external corrosion
- Weatherproof
Control Cabinet
- Diverter valve for balancing up and down stream pressures on the pipeline valve
- Filter to ensure the control components are supplied with clean gas
- Regulator to control the gas supply pressure to the actuator
- Pressure switch to provide shut down signal on sensing rising/falling downstream pressure
- Directional control valve, with manual push button, closes valve on receipt of shut down signal
- All control components are tubed together using stainless steel tube and fittings
- All control components are housed in a weatherproof cabinet