Casing Hanger Mandrel Seal Isolation with Mac-Seal
Challenge:
KCI were requested by a major UK Oil and Gas Operator to provide an isolation on a Vetco Wellhead due to A to B Annulus communication. The Well is a gas lift design and the A Annulus gas pressure was charging the B Annulus.
Severe freezing was witnessed on the external body of the 9 5/8” Casing Spool when venting down the B Annulus indicating that there was a significant gas leak path causing the external icing on the wellhead.
The well was shut-in due to this major Well Integrity issue.
Solution
Test medium fluid was injected into the Casing Hanger assembly to confirm the leak path – Leak verified. 1.8 Litres of Mac-Seal 02 was deployed into the 9-5/8” Casing Hanger Mandrel Void to establish the isolation. 0.5 Litres of Mac-Seal 01 (thinnest viscosity) was deployed to isolate the split or damaged BT Seal
assembly. Once the Mac-Seal had cured the 9-5/8” Casing
Hanger Mandrel Void was tested using the A & B Annuli pressures. With full Gas Lift pressure on the A Annulus, the B Annulus was successfully vented off with no pressure build-up or external freezing witnessed on the external body of the wellhead.
Result
The Isolations were successful and the well was brought back online safely. Our customer was extremely satisfied with our safe, effective & efficient Isolation. This value adding, rigless isolation operation saved the well owner from a potentially time consuming and costly well workover or lost production from a long term suspension.