
After devastating South Florida during August 25, 1992, Hurricane Andrew struck Gulf of Mexico facilities the following day. Sustained winds were 140 mph with gusts to 160 mph, and significant wave heights were 35-40 feet. About 700 platforms were exposed to hurricane force winds. 241 platforms and 83 pipeline segments incurred substantial damage.
All workers had been evacuated from the offshore facilities without incident. Surface and subsurface safety systems performed as intended, and there were no uncontrolled flows from production wells. According to respondents to a JP Kenny survey for MMS, 2698 valves were closed during the storm as follows:
valve type | activated | failed |
subsurface safety valves | 716 | 0 |
master surface safety valves | 729 | 5 |
wing surface safety valves | 460 | 0 |
pipeline shutdown valve | 415 | 0 |
pipeline check valve | 378 | 0 |
The five MSSV failures were at facilities directly in the path of the eye in an area where the storm damage was most severe.
The valve performance reporting was associated with a research project and was thus voluntary. It’s therefore important to give credit to the companies that participated (a number of which no longer exist): Amoco, Aquila Energy, BP, Chevron, Four Star O&G, Gulfstream, Houston Expl., Kerr-McGee, Mobil, Pennzoil, Samedan, Shell, Sonat, Stone, Tennessee Gas PL, Texaco, and Unocal.
Also, in reviewing the survey responses it’s clear that there was some confusion about what to report. Most facilities were completely shut-in well ahead of the storm’s arrival and the survey requests information on valves that were shut-in (presumably automatically) during the hurricane. Reporting was therefore inconsistent, and the total number of shut-in valves was under-reported.
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