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Well integrity issues Mature oil and gas wells and abandoned wells attract various well integrity issues. One example of this is a long-abandoned well which has re-pressurized and started to leak through a "cracked" or poor cement job, creating the potential for an environmental disaster. A recent survey by the Petroleum Safety Authority (PSA) Norway revealed that 18 percent of the wells studied in the Norwegian Continental Shelf have some form of weakness/uncertainty regarding well integrity. Lack of well integrity can have disastrous safety consequences, with a blow out being the worst case scenario, if the operator does not have a full overview of well condition at all times. Environmental and financial pressures of using rubber seals have raised questions about the integrity and longevity of this technology. Mature or abandoned wells are susceptible to leaks and increases in pressure, making a reliable downhole seal even more crucial. Metal seals are especially advantageous as the seal provides a complete metal barrier in the well. A metal barrier is extremely durable and reliable even with changing downhole conditions, and will certainly reduce the risk of any environmental issues. The MTM seal enables operators to confidently develop reservoirs that up to now have presented real problems. In addition to the technical advantages, the seal will also provide a commercial benefit as one seal is suitable for any downhole condition regardless of temperature, pressure, corrosive environment or chemicals injected, thus significantly reducing stock levels. Caledyne has developed permanent as well as retrievable bridge plugs which qualify to the highest standards of extreme high temperatures and pressures.
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