In mid-March DI specialists have carried out work on the isolation zone of drilling mud in the well No.103 of the Olympic field.

While drilling at a depth of 1729m with 8-1/2" bit the drilling company NPP Burenie encountered a problem of drilling mud total loss. The angle at this depth was 3 degree.

The loss zone was already well studied and familiar for drilling company. Due to that it was decided to fully reveal the problem area without circulation using the underreamer RRM-216/241.

- Drilling was continued to a bottom 1833m.

- Then it was carried out the caliper log job for the reamed interval.

- Based on caliper data it was decided to run the Profile Liner with length 99.4 m to isolate the interval 1714-1813,4 m

- Profile liner was set in the planned interval by creating a differential pressure in drill string 15MPa (2250 PSI).

- Next was made the reaming of Profile Liner using an auxiliary tools - Reamer RSH-196, RSH-208, RSH-216 and RSH-217, 5.

After installation of the profile liner the circulation was restored to 100% and ensure free passage of BHA with 8-1/2" bit.

At the moment it's continuing drilling of the well No.103 of Olympic field.