Patent ID: 8205676
Filing Date: 2012-06-26
Classification: E21B

Abstract:
1. A system for cleaning water well casing of a water well having a well bore and a metal casing installed within the well bore, the casing having internal sidewalls of a given internal diameter and having at least a length thereof which is perforated to allow the flow of water from a surrounding subterranean formation, the system comprising: a non-rotating tubing string formed from a synthetic polymeric material and having a surface end and a distal end; a bearing assembly attached to the distal end of the tubing string and adapted to be lowered to a predetermined depth within the well bore, the bearing assembly having a generally tubular body with an internal flow path which provides a path for a cleaning fluid and having a central axis; a jet carrier rotatably mounted on the bearing assembly along the bearing central axis for rotation about the central axis, the jet carrier having a carrier body with a pair of outwardly extending tubular arms which extend from the carrier body generally perpendicular to the central axis of the bearing assembly and of the carrier body, each arm terminating in a spray nozzle; a source of pressurized cleaning fluid which communicates with the jet carrier for supplying fluid under pressure to the nozzles, each of said nozzles being adapted to expel the cleaning fluid against the casing internal sidewalls with an inertial force, the inertial force having an equal and opposite reactive force, at least one of the nozzles being mounted in the carrier body such that said reactive force is directionally offset from said carrier axis, thereby creating a twisting moment about the axis tending to rotate the carrier about the carrier central axis; a take up reel located at the well surface for vertically moving the tubing string and carrier within the well bore; wherein the length of the outwardly extending tubular arms on the carrier body is a predetermined distance, so that the spray nozzles located on the arms are positioned from within about ½ inch to 1½ inches from the perforations in the casing internal sidewalls in use; and wherein there are six fixed outlets on the carrier body, each having a ¼ inch type F NPT opening, and wherein a nipple is mounted in each outlet which is ¼ inch M NPT by ⅛ inch F NPT, so that the resulting assembled nozzles are ⅛ inch F NPT with an orifice size of 0.072 inch diameter and with a 25 degree spray.