Progressing cavity pump in which rotor depth can be determined without disassembly of above ground equipment, and methods, systems and tools relating to same

Abstract

An improved progressing cavity pump, methods of making the same, methods of using the same, and methods of retrofitting conventional progressing cavity pumps are disclosed. The improved progressing cavity pump has an improved polished rod, which is connectable to a slider tool, that enables the rod string, including the pump's rotor to be lowered in the production tubing without requiring disassembly of the above ground equipment. Preferably, the slider tool functions to extend the length of the improved polished rod, and the connection between the slider tool and the improved polished rod is preferably configured to ensure that the outside diameter of the connection is no larger than the passageways of the above ground equipment it needs to pass through, when it is lowered. Also disclosed is an improved polished rod clamp. An indicator which enables an operator on the ground to visually determine whether a progressing cavity pump is operating, or whether it is operating correctly is also disclosed.

What is claimed is: 
     
         1 . A polished rod for suspending a rod string in a production tubing of a progressing cavity pump, said polished rod comprising:
 an elongate body defining a first end and a second end;   a threaded connector at said first end, said first threaded connector being positioned coaxially inward of said elongate body, and having a diameter less than a diameter of said elongate body;   a second threaded male portion positioned on said elongate body at said second end, said second threaded male portion being configured to connect to a second rod string component; and   a shoulder on said first end between said diameter of said elongate body and said diameter of said threaded connector.   
     
     
         2 . The polished rod as claimed in  claim 1 , further comprising a first threaded male portion positioned on said elongate body at said first end, said first threaded male portion being configured to connect to a first rod string component. 
     
     
         3 . The polished rod as claimed in  claim 1 , wherein said threaded connector extends from said first end. 
     
     
         4 . The polished rod as claimed in  claim 1 , wherein said threaded connector recedes into said first end. 
     
     
         5 . The polished rod as claimed in  claim 1 , wherein said elongate body is cylindrical. 
     
     
         6 . The polished rod as claimed in  claim 1 , wherein said elongate body has a standard polished rod length. 
     
     
         7 . The polished rod as claimed in  claim 6 , wherein said standard polished rod length is from about 6 feet to about 60 feet, inclusive. 
     
     
         8 . The polished rod as claimed in  claim 1 , wherein said first or second string component is a rod coupler, a sucker rod, or an endless rod reel. 
     
     
         9 . The polished rod as claimed in  claim 1 , wherein said diameter of said threaded connector is from about ¾ inch to about 2 and ½ inches, inclusive. 
     
     
         10 . The polished rod as claimed in  claim 1 , wherein said diameter of said second threaded male portion is from about ½ inch to about 1 and ½ inches, inclusive. 
     
     
         11 . A progressing cavity pump comprising:
 said polished rod defined by  claim 1 ;   said rod string suspended from said polished rod in said production tubing;   said rod string including a rotor; and   said production tubing including a stator.   
     
     
         12 . A method of making the progressing cavity pump of  claim 11 , the method comprising the steps of:
 providing a conventional progressing cavity pump having a conventional polished rod; and   replacing said conventional polished rod with said polished rod defined in  claim 1 .   
     
     
         13 . An indicator for use with a polished rod installed in a progressing cavity pump, said indicator comprising:
 a body defining two ends;   a connector attached to one of said two ends, said connector being sized and shaped to removably attach to a free end of said polished rod; and   a marker attached to the other of said two ends;   wherein when attached to said one end of said polished rod, said connector helps to protect said one end from damaging effects of the environment, and said marker indicates to an operator whether the progressing cavity pump is operating.   
     
     
         14 . The indicator as claimed in  claim 13 , wherein said connector is sized and shaped to connect to said threaded connector of said polished rod defined in  claim 1 . 
     
     
         15 . The indicator as claimed in  claim 13 , wherein said marker has a polygonal shape, or a three-dimensional shape. 
     
     
         16 . The indicator as claimed in  claim 15 , wherein said marker has a circular shape, a rectangular shape, a square shape, a triangular shape, a polygonal shape, a spherical shape, a cylindrical shape, or a conical shape. 
     
     
         17 . A slider tool for use with said polished rod defined in  claim 1 , said slider tool comprising:
 an elongate body defining a first end and a second end, said first end being sized and shaped to be gripped by, held by, or attached to, above ground equipment of said progressing cavity pump;   a threaded connector at said second end, said threaded connector of said slider tool being positioned coaxially inward of said elongate body of said slider tool, and having a diameter less than a diameter of said elongate body of said slider tool;   a shoulder on said first end between said diameter of said elongate body of said slider tool and said diameter of said threaded connector of said slider tool;   wherein said threaded connector of said slider tool is adapted to threadingly engage said threaded connector of said polished rod; and   wherein said slider tool permits an operator to lower said polished rod in said production tubing without disassembling said above ground equipment.   
     
     
         18 . The slider tool as claimed in  claim 17 , wherein said elongate body of said slider tool has a diameter that is equal to or less than said diameter of said polished rod. 
     
     
         19 . The slider tool as claimed in  claim 17 , wherein said threaded connector of said slider tool extends from said second end of said slider tool. 
     
     
         20 . The slider tool as claimed in  claim 17 , wherein said threaded connector of said slider tool recedes into said second end of said slider tool. 
     
     
         21 . The slider tool as claimed in  claim 17 , wherein said threaded connector of said slider tool and said threaded connector of said polished rod are adapted to form a connection that is sized and shaped to pass through a stuffing box of said progressing cavity pump. 
     
     
         22 . The slider tool as claimed in  claim 17 , wherein when said threaded connector of said slider tool threadingly engages said threaded connector of said polished rod, said shoulder of said slider tool abuts said shoulder of said polished rod. 
     
     
         23 . The slider tool as claimed in  claim 17 , wherein said first end is sized and shaped to be gripped by, held by, or attached to, a flush-by or service rig. 
     
     
         24 . A polished rod clamp comprising:
 a pair of clamp members adapted to clamp a polished rod therebetween, each said clamp member having at least two apertures;   at least two bolts, each said bolt being adapted to pass through said apertures from one of said pair of clamp members to the other of said pair of clamp members; and   at least two extended nuts, each said extended nut being adapted to secure to one of said at least two bolts, to clamp said polished rod between said pair of clamp members;   wherein each of said at least two extended nuts has a length greater than a conventional nut, causing said at least two extended nuts to project out from a side of said clamp member by an increased distance to facilitate installation and removal of said polished clamp by a user with conventional tools in the field.   
     
     
         25 . The polished rod clamp as claimed in  claim 24 , wherein said at least two extended nuts each have a length in a range of about ¾ inch to about 1 and ½ inches, inclusive. 
     
     
         26 . A kit comprising:
 said polished rod defined in  claim 1 ; and   said slider tool defined in  claim 17 .   
     
     
         27 . The kit according to  claim 26 , further comprising at least one of the polished rod clamp as defined in  claim 24  and the indicator as defined in  claim 13 . 
     
     
         28 . A method of making the polished rod defined in  claim 1 , said method comprising the steps of:
 providing a conventional polished rod having an elongate body having two ends; and   machining one end of said conventional polished rod to form said threaded connector at said one end, said threaded connector being positioned coaxially inward of said elongate body of said conventional polished rod, and having a diameter less than a diameter of said elongate body of said conventional polished rod.   
     
     
         29 . The method as claimed in  claim 28 , wherein said machining step forms said threaded connector to extend from said one end. 
     
     
         30 . The method as claimed in  claim 28 , wherein said machining step forms said threaded connector to recede into said one end. 
     
     
         31 . A method of checking or setting a depth of said rotor of the progressing cavity pump of  claim 11 , said method comprising the steps of:
 providing said slider tool as defined in  claim 17 ;   connecting said threaded connector of said slider tool to said threaded connector of said polished rod;   connecting said first end of said slider tool to said flush-by or service rig;   raising said slider tool with said flush-by or service rig enough to unseat, and enable removal of, a polished rod clamp attached to said polished rod;   removing said polished rod clamp from said polished rod;   lowering said slider tool with said flush-by or service rig until said rotor reaches a reference point;   raising said slider tool with said flush-by or service rig by a predetermined space-out distance;   installing said polished rod clamp on said polished rod;   lowering said slider tool with said flush-by or service rig to seat said polished rod clamp; and   disconnecting said slider tool from said polished rod.   
     
     
         32 . A method of flushing the progressing cavity pump of  claim 11 , said method comprising the steps of:
 providing said slider tool as defined in  claim 17 ;   connecting said threaded connector of said slider tool to said threaded connector of said polished rod;   connecting said first end of said slider tool to said flush-by or service rig;   raising said slider tool with said flush-by or service rig to free said rotor from said stator;   flushing said production tubing with a desired fluid to fee debris build up in said stator;   lowering said slider tool with said flush-by or service rig to seat a polished rod clamp attached to said polished rod; and   disconnecting said slider tool from said polished rod.   
     
     
         33 . A method of retrofitting a conventional progressing cavity pump having a conventional polished rod, said method comprising the steps of:
 connecting said conventional polished rod to a flush-by or service rig;   raising said conventional polished rod with said flush-by or service rig towards limit of travel imposed by above ground equipment;   disassembling above ground equipment to free said conventional polished rod from said production tubing to enable its removal from said conventional progressing cavity pump;   disconnecting said conventional polished rod from said rod string and removing said conventional polished rod from said conventional progressing cavity pump;   connecting said polished rod as defined in  claim 1  to said rod string;   reassembling said above ground equipment; and   lowering said polished rod in said production tubing with said flush-by or service rig.