摘要 |
A high integrity protection system (HIPS) for the protection of a piping system downstream of a wellhead has an inlet connected to the wellhead and an outlet connected to the downstream piping system and includes: two sets of series-connected surface safety valves (SSVs) in fluid communication with the inlet, the two sets being in parallel fluid flow relation to each other, each set of SSVs consisting of two SSVs in series, either one or both of the two sets of SSVs operable as a flowpath for fluids entering the inlet and passing through the HIPS outlet to the piping system; two vent control valves (VCVs), each of which is connected to piping intermediate each of the two series-connected SSVs, each of the VCVs being in fluid flow relation to each other, each set of SSVs consisting of SSVs in series, either one or both of the two sets of SSVs operable as a flowpath for fluids entering the inlet and passing through the HIPS outlet to the piping system; two vent control valves (VCVs), each of which is connected to piping intermediate each of the two series connected SSVs, each of the VCVs being in fluid communication with a vent line, whereby, upon opening of a VCV, process pressure between the two SSVs is vented; a signal-generating safety logic solver, in accordance with preprogrammed safety and operational protocols; and pressure sensing transmitters attached to piping upstream of the HIPS outlet. The HIPS performs independent, tight shut-off tests of each of the series-connected SSV sets and all valves are closed in the event of an electrical and/or hydraulic system failure.
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