APPARATUS AND METHOD FOR PREVENTING DAMAGE TO A DOWNHOLE PUMP IMPELLER

摘要

The present invention provides a method for preventing damage to a downhole pump impeller of a downhole pump such as a geothermal downhole pump, comprising the steps of setting a rotatable part of a downhole pump to a selected depth, monitoring the depth of the rotatable part, determining that the depth of the rotatable part has significantly changed, and taking a corrective action to return the depth of the rotatable part to said selected depth in order to prevent damage to an impeller that is liable to be caused by a change in depth of the rotatable part. The present invention is also directed to a downhole pump such as a geothermal downhole pump, comprising a line shaft, an impeller engaged with the line shaft for pressurizing fluid to be extracted from a well, and monitoring apparatus for monitoring the depth of a distal end of the line shaft in order to prevent damage to the impeller that is liable to be caused by a change in depth of the distal end.

主权项

1. A method for maintaining a downhole pump impeller of a geothermal downhole pump in a geothermal production well, comprising the steps of
locating a line shaft of the downhole pump to a selected depth in the geothermal production well, monitoring the depth of a lowermost distal end of said line shaft in the geothermal production well using a monitor positioned at a lowermost distal end of said line shaft in order to prevent damage to said impeller, determining that the depth of the lowermost distal end of said line shaft has significantly changed, and taking a corrective action to return the depth of the lowermost distal end of said line shaft to said selected depth in order to maintain and prevent damage to said impeller, wherein the depth of the lowermost distal end of line shaft distal end is monitored by directing a beam of light emitted from a housing mounted on a outer portion of the downhole pump onto a plurality of reflective elements located on the line shaft distal end, and determining whether a receiver mounted in said outer portion receives light reflected from said one plurality of reflective elements.