Reaching Deep Reservoir Targets Using Solid Expandable Tubulars
For years operators have been forced to set drilling liners prematurely due to downhole conditions such as lost circulation and abnormally pressured formations. The conventional solutions for running unplanned casing strings have prevented some operators from reaching the well’s projected target with sufficient casing inside diameter (ID). Not only has this conventional solution been a hindrance to maintaining sufficient IDs, it has proved unsuccessful when aiming for certain ultra -deep reservoir targets. Reduced hole size may lead to an inaccurate evaluation of the reservoir or prevent the reservoir from being produced efficiently. Solid expandable tubulars add flexibility and versatility to operators’ casing programs when encountering abnormal downhole restraints and obstacles. Additional casing strings can be proactively incorporated into the well program making the odds of reaching the target more realistic. With recent technological advancements, solid expandable tubulars are providing the added benefit of obtaining the optimum available casing ID when a drilling liner is needed. The expanded liner ID, approximately 10 to 20% above conventional liners, can put drilling programs back on track in a cost-effective manner. Solid expandable tubulars can and have been the difference between sidetracking or plugging the well altogether. Having a solid expandable tubular contingency string on standby gives an operator the added option of pushing a given hole section even further than planned when pursuing deep reservoirs. This paper discusses how using solid expandable tubulars improve an operator’s ability to reach a proposed well target successfully. Insight into the industry’s growing acceptance of using solid expandable tubulars in the initial engineering of a well is included, along with the economical benefits of using this technology not only as a contingency casing string but also as a primary casing string.