Oil well and method for production of oil through permafrost zone

摘要: Production oil wells for extracting warm from ground containing a permafrost zone without causing the to melt comprise pipe extending down into pool, an inner casing surrounding and running through zone, outer spaced define airgap or annulus with means, such as liquid heat exchange fluid refrigerating boiling liquid, in inhibit transfer casing. In preferred embodiments second airgap, optionally filled insulation, is provided between pipe.