Leading Edge of Well Abandonment and Workover Method Revolution for Sidetrack Drilling Preparation in Mahakam

Abstract

Mahakam is an oil and gas field concession area managed by Pertamina Hulu Mahakam which has production for more than 50 years and has been classified as a brownfield because of the marginal reserved and declining production profile. In order to increase the economic value of the drilling process, sidetrack drilling has been introduced into Mahakam area to utilize non-producing well slot in the existing platform instead of building a new one. To carry out sidetrack drilling, the well abandonment and workover operation are done to prepare the old well slots. Revolution of method is initiated to conquer challenges to the more economical operation. Use of rigless unit using hydraulic workover unit and well intervention remote unit, plug and cut wireline technology, cement plug through existing tubing completion, cut and pull tubing / casing using fishing tool, improve well integrity by cementing through annulus casing, wireline gauge ring for checking casing clearance and other initiatives have been introduced to ensure the success of the sidetrack drilling preparation operation. The positive impact of the method is shown by the last milestone on the well abandonment and workover operation delivery within 3.5 days using rigless unit. It breaks the fastest record in Offshore Mahakam Field operation with 90% efficiency in well duration and cost. This achievement has become the leading edge innovation which brings significant economic value for the future development in Mahakam.