Patent ID: 8936091
Filing Date: 2015-01-20
Classification: E21B,Y10T

Abstract:
1. A well jet assembly for degassing coal beds, the well jet assembly comprising a pump arranged in a flow string going in a well through coal beds, characterized in that the pump being a jet pump and arranged in an inner cavity of the lower portion of the flow string, which lower portion goes through coal beds and has a length is greater than a depth of occurrence of a bottom boundary of a lowermost coal bed, and a lower support ring with a filter-type shoe attached via a sub, to a lower part of the lower support ring, the lower support ring being arranged on a lower portion of the flow string below the bottom boundary of the lowermost coal bed, an upper support ring with drain ports is arranged on the flow string higher, above a top of an uppermost coal bed, a packer is arranged on an outer surface of the flow string under the drain ports and above the top of the uppermost coal bed, and a body of the jet pump is arranged on the lower support ring, said body provided with: a seat for installing a removable insert with a nozzle and a mixing chamber with a diffuser, a channel for draining a mixture of a working fluid and pumped out fluid, and a channel for supplying a fluid pumped out of a well, and having a check valve arranged therein, wherein the body of the jet pump being connected, in its upper part, with the lower part of a pipe for supplying a working medium, said pipe being provided with a sealing element, said sealing element being arranged on the upper support ring and an input hopper for receiving the removable insert.