We are planning for the retrieval of a 3½ dual-bore completion. I wonder if anyone has used, or has an approved design for, a test tool for dual-bore rams. The operation is likely to be of relatively short duration so the plan is for testing on the stump rather than on the well.
Simply make a couple of blind test-subs, with reasonable OD and screw onto the lower end of 2 x 3 1/2" tubing joints. With the BOP mounted on its test stump, lower the tubing joints/ test subs through the open dual-tubing rams, Close the rams and p/test from below. The tubing joints may move upwards, until the test sub is supported below the closed dual-tubing rams.
As I indicated to Dave T, the issues we had with UMC dual completions were:
- we needed a set of 'orientation rams', mounted in a ram cavity above the dual-tubing rams, which had to be closed first, to ensure that the dual tubing strings were correctly orientated to allow the dual tubing rams to close, otherwise the dual tubing rams won't be able to close on misaligned tubing strings.
- we got 'Salvasens' to develop a set of special dual-slips & elevators, which enable us to hydraulically separate the tubing strings at the rotary table to ease the use of the powers tongs, with the close spacing of the dual strings in the slips.
I am unsure of your specific application and scope of work, but I may be able to advise further if requested.
We had used 2-7/8" dual bore rams many times before. But it requires quite some arrangement to separate the two tubings, otherwise it could be crashed. Depending on the facility of the Rig, it could be done on the stump.