Offshore Live Well Fishing

OFFSHORE LIVE WELL FISHING

Background

To be able to perform maintenance and repairs to the wellhead and X-mass tree, the well was temporary plugged with two independent barriers. One of the barriers consisted out of a Wireline retrievable Bridge Plug which was placed inside the 5-1/2" production tubing at a depth of 12,700 ft - measured depth along hole (MDAH). Directly above the plug, a Wireline retrievable junk catcher was installed. After finishing the activities, the junk catcher and bridge plug were to be retrieved with Wireline. After several attempts to retrieve the Junk catcher the wireline pulling tool was lost in the hole. Equipment with more pull capacity was required to pull the lost pulling tool, junk catcher and plug out of the hole.

Objective

The objective was to retrieve to lost pulling tool, the juck catcher and the bridge plug from the well. Killing the well was not possible because of the bridge plug. The operation had to be conducted with great care in order to prevent any damage to the existing 5-1/2" production completion.

Execution

A HWU/Snubbing unit was selected for this offshore live well fishing operation. The first objective was to fish the lost wireline GS pulling tool. For this reason, the first Bottom Hole Assembly (BHA) consisted out of a flow-release pulling tool suitable for a JDC style fishing neck. The BHA was run on 2-7/8" drill pipe. The pulling tool parted and half of the pulling tool was recovered back to surface. A BHA consisting out of a overshot dressed with a spiral grapple, double acting Jar and accelerator was used to recover the remaining part of the wireline pulling tool. To retrieve the junk catcher, a BHA consisting out of a GS tool, single acting jar and accelerator was used. Around 30 jar actions were required to retrieve the junk catcher back to surface. After the junk catcher the bridge plug was successfully retrieved.

Results

The bridge plug, the junk catcher, and the lost pulling tool were all successfully recovered without killing the well. The production completion was not damaged. All BHA's, including jars, were stripped in and out of the live well successfully. Bad weather and extremely heavy winds (wind speeds up to 99 knots) were causing an increase in non productive time (NPT). The whole operation was carried out without any incidents or accidents.
Difference in pull capacity between Wireline, Coiled Tubing and HWU/Snubbing