Shell Offshore, Inc.
Attendees:
Shell Deepwater Production
Barry C. Ellis, Seal-Tite® International
Enterra Chemical Injection Mandrel
Preheat, Inc.
Shawn Higganbotham, McMurry – Macco

This report is designed to explain the effects that were encountered when a trial application of Seal-Tite® sealant was applied to the chemical injection mandrel. The following test was performed at NOVA Technology Corporation’s Lafayette facility on October 23, 1998.

The following is a sequential chain of events:

1. Mandrel was pre-heated to 150 degrees using Pre Heat, Inc. of Broussard, Louisiana.

2. Check valves on mandrel were removed to allow the installation of an altered fitting into the inlet port of the valve. (This fitting was a 1/2″ NPT Nipple that was cut across the threads using a shop saw and then installed with a 1/2″ collar.)

3. The check valves along with a supply line from a nitrogen source were installed. (At this time McMurry installed a spring loaded 2,000 psi internal valve Macco to simulate a back pressure from FTP/flow tubing pressure.) The manifold provided by FMC was used to simulate sub-surface fittings and restrictions that may be encountered in this system.

4. The nitrogen source was opened and an immediate leak was detectable at start up on the altered fitting.

5. The severity of the leak we created was very severe and it was doubtful that we could repair that large of a leak path. We proceeded with the test to show the effects of a severe leak in a chemical injection system.

6. We proceeded to pump MB 525 through the leak path to insure that the flow stream was clean and unobstructed. No pressure build-up was encountered at the pump.

7. We then mixed a solution of Seal-Tite® and MB 525 and pumped this solution into the leak path and attempted to seal the leak.

8. The severity of this leak did not allow us to seal the leak in this altered fitting.

9. The decision to replace the altered fitting with one that would leak without alteration was made to show the effects of Seal-Tite® sealing a leak.

10. A 1/2″ NPT fitting was installed hand tight and then backed out two turns to allow a noticeable leak path when nitrogen was applied.

11. When nitrogen was applied to this fitting a very noticeable leak occurred.

12. When the pump was engaged using Seal-Tite® to pump into the leak path an immediate sealing of the leak occurred.

13. After the leak was repaired and pressure increased to 2,000 psi the internal valve opened allowing excess sealant to flow out into the tubing cavity.

14. A pressure test was done for 90 minutes against the 2,000 psi internal valve and no leak was found.

15. The internal valve was removed and a dummy valve was installed to allow increased pressure to be applied to 5,000 psi.

16. At 5,000 psi the Walther coupling provided by FMC started leaking and we were forced to reduce our pressure to 2,500 psi and monitor for leaks.

17. No leaks were found and the 2,000 psi internal valve was reinstalled and a flush procedure was applied to insure the chemical injection system was unobstructed and reusable. Upon inspection on the system it was discovered that the integrity of the Seal-Tite® seal was intact and the chemical injection system was unobstructed and usable.

18. The 2,000 psi internal valve was taken to McMurry Macco for inspection and reports indicate that the valve although had residual sealant was not affected or damaged in any way.

19. The manifold provided by FMC did not show any signs of residue in any of its components.