Apparatus for increasing productivity by cutting openings through casing, cement and the formation rock

摘要

A perforator to increase conductivity of a deposit bearing region of oil, gas, and/or water saturating a rock formation having a wellbore hole therethrough and, thus, increase production by cutting elongated openings (slots) through casing, cement bond and formation rock. The perforator is attached to the bottom end of a string of drill pipes. The string of drill pipes are connected to a surface raising and lowering device for raising and lowering the string of drill pipes into a wellbore hole. A pump pumps an abrasive liquid into the perforator through the string of drill pipes. The perforator has telescoping nozzles and double jet nozzles. The abrasive liquid is jetted at a high velocity out of the telescoping jet nozzles and the double jet nozzles. By shifting the perforator with the raising and lowering device while pumping the abrasive liquid into the perforator, slots are cut in the casing, cement bond and formation rock along wellbore axis. A stream of abrasive liquid ejected from the telescopic jet nozzle penetrates and deepens the slot made by a stream of abrasive liquid ejected from double jet nozzles. The abrasive liquid returns to the surface of the well in the annulus between the casing and the string of drill pipes to the wellhead and exits the annulus through the side outlet.