The standard configuration of HIPPS has all subcomponents supplied loose. The minimum scope of supply consists of: actuated HIPPS valves, initiators, logic solver cabinet or equivalent mechanical system, and partial stroke device. As a minimum, SIL certification of the whole system and IFAT (Internal Factory Acceptance Test) are part of scope of supply. Based on pneumatic or hydraulic configuration other components may be added: hydraulic power unit, interlocking manifold etc.
Selecting one integrator to supply the whole HIPPS makes a one stop-one shop procurement approach possible, minimizing technical risks.
The HIPPS safety loop is designed and tested in a functional safety simulation through an IFAT (Integrated Factory Acceptance Test), minimizing site technical issues.
ATV HIPPS TUV Certified Functional Safety engineers provide functional safety engineering support from early project phases to periodic SIL revalidation.
The valve is the main component of the safety loop. Based on application, fluid composition and process requirements different types of valves may be suitable: Gate Valve, Ball Valve, Axial Valve. ATV HIPPS is able to choose the best option within ATV brand wide product basket or with any valve supplier based on customer’s preference.
The actuator is an important component of the safety loop. The most suitable actuation for HIPPS are Hydraulic and Pneumatic actuation based on available power supply. Self-acting actuation is an option as well when no power supply is available. Electric actuation is less common. ATV HIPPS can supply actuators from the market or its own actuators.
The logic solver is a very important component of the safety loop. Programmable or Solid State Logic Solvers are available based on SRS and Customer SIL goals. SIL 3 or 4 equipment is available in the market based on customers’ requirement and preference. An additional logic solver-free solution is available, using traditional mechanical HIPPS systems.
The pressure transmitters are the most common and suitable initiators of the safety loop. A pressure transmitter is an electronic instrument sensing the process fluid pressure and generating a 4-20mA signal to the logic solver, according to the calibration range. The recommended configuration is 2oo3.
Partial Stroke Device
The partial stroke device is a must in order to increase and keep required SIL levels. A certain number of partial stroke tests per year could be necessary to comply with SIL requirements. It depends on the reliability data of the final element components and the installation architecture. Different technical solutions are available.
The interlocking manifold allows safer operation of initiators. The interlocking manifold allows the system to isolate and vent the lines of only one initiator at a time, via a predetermined sequence in order to avoid spurious trips or problems due to misoperation. Special attention is required for selections based on process fluid composition.
Hydraulic Power Unit
Hydraulic power units are normally mounted on the skid close to HIPPS valves. Accumulators for emergency strokes are installed on the valves or on the skid. Various configurations in terms of pumps and pump logics available.