A HIPPS Safety System (High-Integrity Pressure Protection System) protects critical processes in plant sections as chemical facilities or oil refineries from impermissible overpressures. The HIPPS Safety System provides reliable protection of downstream equipment before it is subject to pressure above design pressure. As a result the equipment is protected against damages such as bursting of pipes. For this reason the HIPPS Safety System is considered as barrier between high and low pressure system of an installation and can alternatively be designed as mechanical or electrical HIPPS Safety System.

Figure 1

The KÜHME HIPPS Safety System is a robust mechanical unit, which intervenes in the pneumatic control circuit of the Safety Shut-Off Valve (QCV = Quick Closing Valve). Therefore it is a very compact and cost economic solution compared to an complex electronically HIPPS arrangement which is much more expensive because of the additional field wiring or electronic data analysis.

Components of the KÜHME HIPPS System are two (2) or three (3)KUEHME Schnellschlussventil mit HIPPS Funktion EN 2 specially designed KÜHME Pilot Valves (PV) as well as one pressure filter regulator. The number of Pilot Valves is depending upon the requested safety level.

Two out of Three Circuit (2oo3) – with 3 PVs:
If already 2 of the 3 Pilot Valves record an overpressure, the Quick Closing Valve will react immediately within less than 1 second.
Refer to Figure 1

One out of Two Circuit (1oo2) – with 2 PVs:
According to this arrangement Quick Closing Valve will be automatically operated if 1 of the 2 Pilot Valves will record an overpressure.
Refer to Figure 2

The Pilot Valves are 3/2 solenoid valves, which in normal mode release the pass of the control medium to the actuator of the Quick Closing Valve (QCV). They are fitted with a measuring chamber, which is directly connected with the pipeline. Through this connection the upstream pipeline pressure is recorded very accurately. If this pipeline pressure exceeds the preset value of the pilot valve, it switches over. As a result the actuator of the Quick Closing Valve is vented and reliably cuts of the medium supply in the main pipeline within less than one second.

The reset of the pilot valve can only be performed after decrease of the pipeline pressure.

This HIPPS-Control Unit is one example out of the wide program of modular options that can be combined KÜHME Valves.

Figure 2