Historically, operators used solid expandable tubulars as contingencies to mitigate unexpected hole problems, minimize loss of hole size and to meet project objectives. However, some operators quickly realized that by incorporating this technology into their initial field development and workover plans, previously untapped reserves could be brought online.

An operator in India combined solid expandable tubulars with sidetracking operations to reach additional reserves with optimized hole size in several offshore wells. Sidetracking out of a milled window results in loss of hole size with consecutive casing strings bringing further reductions. In this common scenario, the operator could be faced with drilling the drain hole with slimhole tools that drastically reduce the flow area and limit logging and drilling equipment availability.

Planning the application of solid expandables through the milled window in these vertical wells allowed the operator to economically extract previously unswept reserves. With conventional technology they were faced with exiting out of the 9-5/8 in. casing and setting 7 in. and 4-1/2 in. liners to isolate problematic and depleted zones above the pay zone. The pay zone would be drilled using 3-3/4 in. slimhole tool strings that placed restrictions in the outflow of the reservoir and compromised the workover program economics.

This paper will discuss how the planned-in use of expandable tubulars enabled the operator to sidetrack and recomplete poor-producing vertical wells into horizontal wellbores. This approach allowed the operator to maintain optimum drain hole that resulted in a five-fold increase in daily oil production. The paper will describe the complimentary technologies used with the solid expandables and the lessons learned in the first two wells. The operator/contractor relationship will also be discussed regarding project management of multi-well workover programs for both offshore and onshore fields.

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