Abstract

The complexity of typical completions in Handil & Bekapai fields, i.e. dual completions in deviated wells to produce selectively 2 to 6 productive layers, leads to very delicate and expensive workovers.

In order to increase oil and gas gain, as well as to increase water-injection points without having to pull out the existing completion string, a light workover (LWO) system has been applied in both fields. LWO operations (which include additional perforations, isolation of perforations or communication by cementation, gravel packing) may involve either slickline wireline, electrical wireline, snubbing, cementing / gravel packing units or any combination of the above, but neither drilling nor work-over unit is involved. LWO's are the last chance to produce a zone having insufficient potential to justify economically a Heavy Work Over.

Since 1986 TOTAL Indonesie has performed successfully more than 50 LWO jobs which have obtained an additional cumulative production of more than 2.4 million barrels oil and 7.0 billion SCF gas and an additional 3.5 million barrels injected water.

The total cost for such jobs was 2.6 million USD or an average of 50 000 USD / LWO. Compared to heavy WO's (pulling out the existing completion string & running in hole a new one) which cost between 0.75 to 2 million USD each, LWO is really the cheapest solution as long as the WO goal is achieveable.