News

3 well interventions at NEDMAG by snubbing unit

December 2013 – February 2014, NEDMAG salt solution mining, Veendam , the Netherlands

Well Engineering Partners completed successfully three Hydraulic Workover Snubbing Operations (HWO). In the 7 weeks, 2 wells were brought back into production and in third well the completion was retrieved as deep as possible. All was done under approximately 120 bar high wellhead pressure. All workover operations were carried out with a Hydraulic Workover Unit (HWU) of Balance Point Control.

Each well had a different scope:

1) Well 1: the injection point was raised above the production point in order to regain production.

2) Well 2: the 7” x 5” production string was retrieved and wireline measurements were performed.

3) Well 3: the damaged 5” x 4 ½” was retrieved and recompleted with a drillable 5” x 4 ½” completion.

In the first well the 3 ½” tubing string was pulled out of the hole. Then the 5” x 4 ½” tubing was lifted up 20m. Perforating guns were run through the lifted tubing string and the 7 5/8” casing was perforated between. After perforations the 5” x 4 ½” tubing was landed back to its original depth and the 3 ½” tubing string was run back into the hole. After the 3 ½” was successfully hung off, the unit was moved to the 2nd well.

At the 2nd well the 4 ½” dilution string was pulled out of the hole. Then the 7” part of the casing string was plugged and pulled out of the hole. With a fishing job with a mechanical cutter the remaining 5” fish was cut as deep as possible and retrieved to surface. After the well was cleared a detailed wireline survey (cement, caliper, etc.) was carried out. The well was suspended by a 7” suspension string.

The HWU moved to the 3rd well. Initially the 3 ½” dilution string was pulled out of the hole. Then the well was killed with floating mud cap and kill mud. After this, the 5” x 4 ½” completion was retrieved. Wireline investigations confirmed good well integrity. A 5” x 4 ½” completion with drill-in BHA was run in hole and drilled from 1700 m to 1900m. A wireline memory tool was used for directional measurements during drilling. At TD, the BHA was severed with a wireline severing tool.