Downhole casing auger for removal of paraffin from oil and gas wells

Abstract

An apparatus and method for removing paraffin from a casing in a borehole of an oil/gas well without using pressure from the well. The apparatus may include a shaft with a plurality of flights wound around the shaft in a spiral pattern. The apparatus may include a coupling on one end for attachment to a drilling string. The method may include lowering the apparatus into the casing down to a paraffin cake lodged in the borehole. The apparatus may be used dislodge paraffin using the flights to cut the paraffin, an end of the apparatus, impact the paraffin, or both. Then the dislodged paraffin may be collected on the flights and lifted out of the casing for disposal.

What is claimed is: 
     
         1 . An apparatus for removing paraffin, the apparatus comprising:
 a longitudinal member having a first end and second end and configured for insertion in a casing of a borehole;   a plurality of flights welded around the outer surface of the longitudinal member in a spiral pattern, wherein each of the plurality of flights have a width that extends substantially to an inner surface of the casing; and   a coupler in mechanical communication with the second end configured to attach the apparatus to a drilling string.   
     
     
         2 . The apparatus of  claim 1 , wherein the longitudinal member is tubular. 
     
     
         3 . The apparatus of  claim 2 , further comprising a piercer disposed on the first end of the longitudinal member. 
     
     
         4 . The apparatus of  claim 3 , wherein the piercer comprises one or more openings configured to allow fluid pumped through the longitudinal member to be released by the piercer. 
     
     
         5 . The apparatus of  claim 2 , wherein the longitudinal member has one or more openings in its surface disposed proximate to the first end. 
     
     
         6 . The apparatus of  claim 2 , wherein the longitudinal member has one or more openings in its surface disposed between two of the plurality of flights. 
     
     
         7 . The apparatus of  claim 1 , wherein the longitudinal member is made of steel. 
     
     
         8 . The apparatus of  claim 1 , wherein the plurality of flights are formed from a continuous piece of metal. 
     
     
         9 . A method for removing paraffin from a casing of a borehole for an oil/gas well comprising the steps of:
 inserting an apparatus in the casing of the borehole down to contact with a paraffin cake, where the apparatus comprises:   a longitudinal member having a first end and second end and configured for insertion in the casing of the borehole;   a plurality of flights welded around the outer surface of the longitudinal member in a spiral pattern that extends from the longitudinal member substantially to an inner surface of the casing; and   a coupler in mechanical communication with the second end configured to attach the apparatus to a drilling string;   rotating the apparatus to cut and dislodge paraffin from the paraffin cake with the plurality of flights; and   lifting the apparatus with the dislodged paraffin to the surface.   
     
     
         10 . The method of  claim 9 , further comprising the step of:
 removing a production tubing from the casing prior to inserting the apparatus.   
     
     
         11 . The method of  claim 9 , further comprising the step of:
 impacting the paraffin cake with the apparatus.   
     
     
         12 . The method of  claim 9 , wherein the longitudinal member is tubular and further comprising the step of:
 injecting a fluid into the paraffin cake through the apparatus, wherein the fluid is selected to loosen, melt, or dissolve the paraffin cake.   
     
     
         13 . The method of  claim 9 , further comprising the step of:
 removing the dislodged paraffin from the apparatus.