Roustabout Energy International – 30.11.08

Caledus the oil and gas service sector business has started the ball rolling on the formation of a slender well alliance. The main aim of the alliance will be to offer the operating companies a joined up and integrated solution to making their wells more slender than they currently are without compromising integrity or performance. In an environment where hydrocarbon extraction costs are still relatively high and commodity prices have lowered well construction cost savings are now more desirable.

The advantages of truly slender or lean profile wells are well understood within the drilling and completions community, especially if the advantages can be gained without significant compromise. In some environments operating companies are forced to reduce the telescoping effect of their casing regimes for good technical reasons but often to the detriment of performance or significantly increased cost. The planned slender profile well can offer a number of significant advantages, from reducing cost for the same performing product through to increasing performance without increasing cost. Lean profile wells can have the same or additional numbers of planned casing seats but produce less drilled formation cuttings to dispose of without compromising the final hole size. Slender wells can consume less steel, require less cement, consume less mud, and could be drilled using a smaller capacity rig either offshore or onshore relative to the standard and accepted well design. Smaller rigs are generally accepted as lower cost regardless of prevailing rig rates. Exploration or finder wells are good candidates for lean profile casing regimes. Project development costs around lean well profiles may be lower. Infill drilling in mature basins can benefit from reduced well cost, increased pipe size at TD or access to otherwise inaccessible reserves with an acceptable pipe size. Slender lean profile wells will usually still be constructed entirely from API casing that the engineer knows the burst, collapse, and tensile ratings of and understands the corrosion and longevity issues related to those API casings given the retained completion and produced well fluids and planned life of well. Additional casing seats could be placed over troublesome zones without having to resort to expandables or an unwanted reduction in the pipe size at the zone of interest.

Caledus already owns intellectual property relating to slender well construction with its SlimWELL® liner technology and is currently in the process of early commercialisation of that standalone technology in several sizes to demonstrate to a wider audience that lean profile wells are practical. More sizes of this tried and tested technology will be introduced in the months ahead. The slender well alliance will be the formation of a group of complimentary companies that offer a solution to the final end product, the slender well, where all the critical interfaces have been considered, appropriate technologies have been identified, risk analysed, risk mitigated, tried and tested in advance to ensure that the expected benefits can be realized and the operating and longevity risks taken down to no more than a currently accepted standard well design. Several companies have already indicated a willingness to join the alliance and Caledus is expecting it to be an actively marketed set of available solutions during 2009.

Any companies interested in providing solutions to the slender well alliance should contact Caledus via www.slenderwell.com