Self-retaining packing nut assembly and method for a high pressure pump

Abstract

A self-retaining packing nut assembly may include a first piece having a first and a second section. The first section can be configured to engage diametrically an inside of a pump housing. The packing nut assembly may also include a second piece having a third and fourth section. The third section can engage diametrically an inner surface of the first piece. In addition, the second piece can be configured to axially adjust inside the first piece.

We claim: 
     
         1 . A self-retaining packing nut assembly, comprising:
 a first piece having a first section and a second section, wherein the first section is configured to engage an inside of a pump housing; and   a second piece having a third and fourth section, wherein the third section engages the inner surface of the first piece,   wherein the second piece is configured to axially adjust inside the first piece.   
     
     
         2 . The self-retaining packing nut assembly of  claim 1 , wherein the second piece compresses a packing located inside the pump housing. 
     
     
         3 . The self-retaining packing nut assembly of  claim 1 , wherein the first section of the first piece includes a nose that engages the inside of the pump housing. 
     
     
         4 . The self-retaining packing nut assembly of  claim 1 , wherein the second section takes the shape of a flange which engages an outside of the pump housing. 
     
     
         5 . The self-retaining packing nut assembly of  claim 1 , wherein the first section has an inner side and an outer side, wherein both the inner side and outer side are threaded. 
     
     
         6 . The self-retaining packing nut assembly of  claim 1 , wherein the second section has an inner diameter that is smaller than an outer diameter of the third section of the second piece. 
     
     
         7 . The self-retaining packing nut assembly of  claim 1 , wherein the second section includes slots, holes, or apertures configured to engage a tool so as to be assembled into the pump housing. 
     
     
         8 . The self-retaining packing nut assembly of  claim 1 , wherein the fourth section includes slots, holes, or apertures configured to engage a tool so as to be axially adjusted within the first piece. 
     
     
         9 . An apparatus, comprising:
 a housing having a bore along an axis therein;   a plunger configured to reciprocate within the bore along the axis;   packing at least partially placed between the plunger and a side of the bore;   a self-retaining packing nut assembly engaging the packing, the self-retaining packing nut assembly comprising:   a first piece having a first section and a second section, wherein the first section is configured to engage an inside of a pump housing; and   a second piece having a third and fourth section, wherein the third section engages on the inner surface of the first piece,   wherein the second piece is configured to axially adjust inside the first piece.   
     
     
         10 . The apparatus of  claim 9 , wherein the second piece compresses the packing located inside the pump housing. 
     
     
         11 . The apparatus of  claim 9 , wherein the first section of the first piece includes a nose that engages the inside of the pump housing. 
     
     
         12 . The apparatus of  claim 9 , wherein the second section takes the shape of a flange which engages an outside of the pump housing. 
     
     
         13 . The apparatus of  claim 9 , wherein the first section has an inner side and an outer side, wherein both the inner side and outer side are threaded. 
     
     
         14 . The apparatus of  claim 9 , wherein the second section has an inner diameter that is smaller than an outer diameter of the third section of the second piece. 
     
     
         15 . The apparatus of  claim 9 , wherein the second section includes slots, holes, or apertures configured to engage a tool so as to be assembled into the pump housing. 
     
     
         16 . The apparatus of  claim 9 , wherein the fourth section includes slots, holes, or apertures configured to engage a tool so as to be axially adjusted within the first piece. 
     
     
         17 . A method, comprising:
 providing a first piece having a first section and a second section;   providing a second piece having a third section and a fourth section;   fastening the third section of the second piece to the first piece;   inserting the first section of the first piece into a pump housing;   engaging first piece with the pump housing; and   axially adjusting the second piece inside the first piece to compress a packing located inside the pump housing.