Linear electric motor for an oilfield pump

Abstract

An oilfield pump employing a linear electric motor. The linear electric motor replaces a conventional crankshaft or hydraulic techniques for driving a plunger of the pump. This may reduce the number of equipment parts and amount of maintenance expenses associated with the operation of oilfield pumps. Furthermore, the use of a linear electric motor may also increase the precision and control over the fluid delivery provided by the pump assembly.

1 . An oilfield pump assembly comprising:
 a plunger for reciprocating relative to a chamber to direct a fluid therefrom; and   a linear electrical motor coupled to said plunger for the reciprocating.   
   
   
       2 . The oilfield pump assembly of  claim 1  further comprising a fluid end to house the chamber, the chamber coupled to a cylinder of the linear electric motor to accommodate a rear of said plunger. 
   
   
       3 . The oilfield pump assembly of  claim 2  wherein said linear electric motor comprises a stator adjacent the cylinder to electromagnetically actuate linear movement of said rear. 
   
   
       4 . The oilfield pump assembly of  claim 3  wherein said stator comprises an array of magnets and cooling fins. 
   
   
       5 . The oilfield pump assembly of  claim 3  wherein said rear comprises:
 a ferrous core; and   an outer layer of bands selected from a group consisting of copper and iron.   
   
   
       6 . The oilfield pump assembly of  claim 3  wherein said movement is substantially frictionless. 
   
   
       7 . The oilfield pump assembly of  claim 1  wherein the reciprocating is to direct the fluid to a well at an oilfield for a well services operation thereat. 
   
   
       8 . The oilfield pump assembly of  claim 7  wherein the well services operation is one of drilling, fracturing, cementing, and dosing. 
   
   
       9 . The oilfield pump assembly of  claim 7  wherein the oilfield pump assembly is a first oilfield pump assembly coupled to the well, the well coupled to a second oilfield pump assembly for obtaining fluid therefrom. 
   
   
       10 . The oilfield pump assembly of  claim 2  wherein said fluid end is one of a triplex configuration and a singular configuration. 
   
   
       11 . An oilfield pump assembly comprising:
 a plunger for reciprocating relative to a chamber to direct a fluid therefrom;   a primary linear electric motor coupled to said plunger for the reciprocating; and   a secondary linear electric motor coupled to said primary linear electric motor for increased power of the reciprocating.   
   
   
       12 . The oilfield pump assembly of  claim 11  wherein the increased power of the reciprocating is to direct the fluid under a pressure of more than about 15,000 PSI. 
   
   
       13 . The oilfield pump assembly of  claim 12  wherein the reciprocating is to direct the fluid to a well for a fracturing operation thereat. 
   
   
       14 . An oilfield pump assembly comprising:
 a primary pump fluid end;   a secondary pump fluid end;   a plunger for reciprocating between a chamber of said primary pump fluid end and a chamber of said secondary pump fluid end to direct fluid from the chambers; and   a linear electric motor disposed between said primary pump fluid end and said secondary pump fluid end and coupled to said plunger for the reciprocating.   
   
   
       15 . The oilfield pump assembly of  claim 14  wherein the reciprocating is to direct the fluid to a well for a drilling operation thereat. 
   
   
       16 . A method of performing a well services operation in a well at an oilfield, the method comprising:
 powering a linear electric motor with an electric power source at the oilfield, the linear electric motor coupled to a plunger; and   employing the linear electric motor to reciprocate the plunger relative to a chamber to direct a well services fluid therefrom and to the well.   
   
   
       17 . The method of  claim 16 , wherein the well services operation is one of drilling, fracturing, cementing, and dosing. 
   
   
       18 . The method of  claim 16 , wherein the well services operation comprises cementing a borehole casing, and wherein the well services fluid comprises a cement slurry. 
   
   
       19 . The method of  claim 18  further comprising:
 driving the cement slurry into the borehole casing through a cementing pipe terminating within the borehole casing; and   forcing the cement slurry into a space between the borehole casing and a wall of the well for stabilization of the borehole casing.   
   
   
       20 . The method of  claim 19  wherein said driving and said forcing occur under pressurization of between about 1,500 PSI and about 15,000 PSI. 
   
   
       21 . The method of  claim 18  wherein said powering delivers between about 150 KW and about 600 KW to the linear electric motor. 
   
   
       22 . The method of  claim 18  wherein the linear electric motor operates at between about 200 Hp and about 800 Hp. 
   
   
       23 . The method of  claim 18  wherein the linear electric motor operates in an electromagnetic polyphase manner.