Print this pageOPPS and HIPS
Over Pressure Protection Systems (OPPS) and High Integrity Protection Systems (HIPS) have an important role in some systems. They can be a particularly beneficial solution when the flaring is unreasonably large or when the process pressure builds quickly and excessive relief valve sizes are needed.
In general, shutdown systems can range from the simple and reasonably common high pressure, level or temperature shutdown systems to the more specialised high integrity versions. Our experience is that the design of all of these shutdown systems is far better if simulation is used. It prevents problems with the wrong set point, spurious trips and systems that are too slow to protect the plant.
Simulation studies allow a complete specification of the system and allow designers and operators to select set points that allow adequate time to shutdown whilst minimising spurious trips.
We have also worked on systems in which the specification of other items of equipment (such as valve closure times) can reduce the speed of the transient disturbance so that shutdown systems do have enough time to respond.
