Introduction to HIPPS
HIPPS is an abbreviation of “High Integrity Pressure Protection System”. HIPPS systems are applied to prevent over-pressurisation of a plant by shutting-off the source of the high pressure. In traditional systems over-pressure is dealt with through relief systems. Relief systems have obvious disadvantages such as release of (flammable and toxic) process fluids in the environment and often a large footprint of the installation. With the increasing environmental awareness relief systems are no longer an acceptable solution.
HIPPS is applied to prevent over-pressurisation of a plant or pipeline by shutting off the source of the high pressure.
HIPPS provides a technically sound and economically attractive solution to protect equipment in cases where:
• High-pressures and / or fl ow rates are processed
• The environment is to be protected.
• The economic viability of a development needs improvement
• The risk profile of the plant must be reduced
HIPPS is an instrumented safety system that is designed and built in accordance with the IEC 61508 and IEC 61511 standards.
What is HIPPS?
The international standards IEC 61508 and 61511 refer to safety functions and Safety Instrumented Systems (SIS) when discussing a device to protect equipment, personnel and environment.
Older standards use terms like safety shut-down systems, emergency shut-down systems or last layers of defence. A system that closes the source of over-pressure within 2 seconds with at least the same reliability as a safety relief valve is usually called a HIPPS.
A High Integrity Pressure Protection System is a complete functional loop consisting of:
• The sensors, (or initiators) that detect the high pressure
• The logic solver, which processes the input from the sensors to an output to the final element
• The final elements, that actually perform the corrective actions in the field by bringing the process to a safe state. The final element consists of a valve, actuator and possibly solenoids.
- High pressures and / or flow rates are processed
- The environment is to be protected
- The economic viability of a development needs improvement
- The risk profile of the plant must be reduced
Overview of HIPPS
- The initiators that detect the high pressure. These initiators may be electronic or mechanical.
- For electronic HIPPS, a logic solver, which processes the input from the initiators to an output to the final element.
- The final elements, that actually perform the corrective action in the field by bringing the process to a safe state. The final element consists of a valve and actuator and possibly solenoids or mechanical initiators.
Two types of HIPPS
1. Integral mechanical HIPPS – using mechanical initiators
- Integrated safety loop to IEC 61508 / EN 12186
- Safe and simple
- Option not requiring external energy (stand-alone HIPPS)
- No wiring required
- Set point accuracy < 1%
- System to SIL 3 or 4
- Third party validated failure data
- Integrated safety loop to IEC 61508 and 61511
- No limit on distance between transmitters and final element
- Communication with Plant Safety System
- Possibility of integrated monitoring
- Hard-wired solid-state logic solver
- High integrity manifold block for safer operation
- System to SIL 3 or 4
HIPPS System: 1002 Electronic HIPPS system
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