Abstract

With the objective to drill two wells shared from one conductor with independent wellhead and completion, ADNOC Offshore drilling team pioneered for the first time in Umm Lulu field and ADNOC UAE the Conductor sharing drilling technique. Which is to drill two wells from one single conductor in wellhead tower. Well planning technique drilling 42" hole and run 36" conductor, then install lower male connector and run conductor Down Hole Guide (DHG) assembly to be a guide for both two wells. Land the DHG on the lower male connector. Install upper male connector, which is equipped with two well slots for drilling the two wells. Drilling 1st 16" hole and run 13 3/8" casing and cemented. Skid over second slot and drill second hole 16" and run and cement 13 3/8" casing and carry out top up cement job for both hole up to surface inside 36" conductor. Install casing head housing for each well. Then each well could be drilled as per normal procedures.

Well executing process.

Well challenges:

Drilling large hole 42" hole with 42" bit and BHA.

Run 36" conductor and conductor sharing DHG and keep aligned for accessibility of BHA and casing Nudge 16" hole for both two wells at centre-to-centre distance 8" safely without collision issue.

Run two 13 3/8" casing strings in 36" conductor and cement same up to surface.

Complete drilling well UL-056 from slot A, drilled 12 ΒΌ" hole section to TH-I ABS, run 9 5/8" casing and perform cement job to surface, drilled 6" hole (linerless design) and land in TH II then continued drilling horizontal drain to TD, Run completion and deliver the well. Suspend the other well in slot B at 13 3/8" casing with securing the well with abandonment cap and as per ADNOC offshore policy.

You can access this article if you purchase or spend a download.