Wellhead HIPS with Automatic Testing and Self-Diagnostics

a technology of protection system and wellhead, applied in the direction of survey, instruments, borehole/well accessories, etc., can solve the problems of environmental pollution, and high cost of replacement, and the topside pressure of the wellhead may exceed the maximum allowed pressure,

US20120221295A2Active Publication Date: 2012-08-30SAUDI ARABIAN OIL CO
7 Cites 4 Cited by

Patent Information

Authority / Receiving Office
US · United States
Patent Type
Applications(United States)
Current Assignee / Owner
Publication Date
2012-08-30

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
  • Figure 3
    Figure 3
Patent Text Reader

Abstract

A method for diagnostics of a high integrity protection system (HIPS) for protection of a pipeline downstream of a wellhead includes: monitoring for initiation of an automatic trip or manual safety shutdown or full shut-off test; determining the process safety time (PST) that elapses between the time at which the upstream pressure reached the trip setpoint and the time at which the upstream pressure reaches the maximum allowable piping pressure (MAPP) of the downstream pipeline; and verifying that the safety critical isolation valves stroked to the fully closed position within ½ PST and that the downstream pressure did not exceed the MAPP. If the verification is successful, no action is required, whereas if the verification shows that either of those parameters are not met, then the HIPS signals an alarm to operators, and in the case of a manual safety shutdown or full shut-off test, resets the pressure trip setpoint to a lower level.
Need to check novelty before this filing date? Find Prior Art

Description

RELATED APPLICATION

[0001] This application is a Continuation-in-Part of U.S. patent application Ser. No. 11 / 648,312 filed on Dec. 29, 2006, which is incorporated herein by reference.FIELD OF THE INVENTION

[0002] The present invention relates to a method and an apparatus for the operation and testing of a high integrity protection system (HIPS) connected to a wellhead pipeline system. BACKGROUND OF THE INVENTION

[0003] In the oil and gas industry, wellhead topside pressure may exceed a maximum allowed pressure within production fluid pipelines downstream of the wellhead due to degraded pipe wall thickness or cost limitations that prevent the installation of full-rated piping. It is therefore necessary that such pipelines be protected against excessive pressure that might rupture the pipe, which would cause environmental pollution and be very expensive to replace. A conventional system used to protect pipelines from over-pressure is the high integrity protection system (HIPS). This i...

Examples

Embodiment Construction

[0043] Referring to FIG. 1, a high integrity protection system (HIPS) 10 is installed in proximity to a wellhead in a piping system to convey a pressurized fluid product, such as oil or gas, from the wellhead 102 to a remote host location via pipeline 104. The HIPS has an inlet 1 connected to the wellhead piping 102 and an outlet 2 connected to piping system 104 through which the liquid product enters and exits the HIPS 10. The HIPS is preferably skid-mounted for delivery to the site of the wellhead and is provided with appropriate flanges and adapters, if necessary, for attachment to the inlet and outlet to the oil field piping.

[0044] Two sets of surface safety valves (SSVs) 11, 12 and 13, 14 are in fluid communication with the inlet 1 and the outlet 2 are thereby operable as a flowline for the fluid product. Each set of SSVs, identified and referred to as SSV-1 and SSV-2, has two SSVs 11-12 and 13-14, respectively, which are connected in series. The SSVs close automatically in th...