Abstract:
Methods and apparatus for utilizing a valve with a pump rotor passage with a downhole production string, the pump rotor being on a rotatable rod with a bobbin moving along the rod between a position for opening the passage to fluid flow, when the bobbin is not seated on a shuttle seat, and a position for closing the passage to fluid flow, when the bobbin is seated on the shuttle seat. The pump rotor and rod are removable through the passage while leaving the pump stator in place upstream of the valve.

Description:
PRIORITY CLAIM AND INCORPORATION BY REFERENCE 
       [0001]    This application is a continuation of U.S. app. Ser. No. 14/634,598 filed Feb. 27, 2015 which claims the benefit of 62/085,633 filed Nov. 30, 2014 and which is a continuation-in-part of U.S. app. Ser. No. 14/061,601 filed Oct. 23, 2013, now U.S. Pat. No. 9,027,654, which is 1) a divisional of U.S. app. Ser. No. 13/089,312 filed Apr. 19, 2011, now U.S. Pat. No. 8,955,601 and 2) a continuation-in-part of U.S. app. Ser. No. 12/766,141 filed Apr. 23, 2010, now U.S. Pat. No. 8,545,190. All the above applications are now incorporated herein by reference, in their entireties and for all purposes. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The present invention relates to a valve for use in a downhole production string. In particular, the valve includes a pump rotor passage. 
       Discussion of the Related Art 
       [0003]    Downhole production equipment is located in hard to reach places and therefore presents significant challenges to operators during both normal and abnormal conditions. 
         [0004]    Downhole production strings may include production facilities such as a valve between a rod driven pump and pipe through which a fluid is transported or produced. For various reasons a valve, pump, and/or pipe may need to be installed in or removed from a downhole location. For example, installation and recovery of production string parts may be for one or more of normal production set up and take down, maintenance, repair, and replacement. 
         [0005]    Relocating production string parts to or from downhole stations is typically a time consuming process involving labor, equipment, and materials. With traditional production string parts, the sequence of steps required to assemble/disassemble and/or deploy/recover downhole production string parts frequently delays relocation operations. 
         [0006]    To the extent that relocation delays are reduced, less production time is lost and production or surfacing of the desired resource, such as a liquid hydrocarbon from a subterranean reservoir, is enhanced. 
       SUMMARY OF THE INVENTION 
       [0007]    The present invention provides a downhole production string valve that includes a pump rotor passage. 
         [0008]    In an embodiment, a valve for use in a downhole production string comprises: a body, a shuttle slidably inserted in the body, and a bobbin for mating with the shuttle; the valve body and shuttle provide a pump rotor passageway; and, the passageway is for receiving a rotatable rod therethrough and the bobbin is for slidably contacting the rod; wherein during normal operation of the production string a pump driven by the rod pumps fluid through the passageway and during a pump rotor removal operation a rotor of the pump is passable through the passageway. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    The present invention is described with reference to the accompanying figures. The figures listed below, incorporated herein and forming part of the specification, illustrate the invention and, together with the description, further serve to explain its principles enabling a person skilled in the relevant art to make and use the invention. 
           [0010]      FIG. 1  is a first schematic diagram of a downhole production string including a valve. 
           [0011]      FIG. 2A  is a second schematic diagram of a downhole production string including a valve. 
           [0012]      FIG. 2B  is a cross-sectional view A-A of  FIG. 2A . 
           [0013]      FIG. 3A  is a third schematic diagram of a downhole production string including a valve with a pump rotor passage. 
           [0014]      FIG. 3B  is a cross sectional view through the valve illustrating pump rotor clearance. 
           [0015]      FIGS. 4A-H  show a diverter valve that provides a pump rotor passageway in a rod driven downhole production system. 
           [0016]      FIGS. 5A-B  are flowcharts illustrating use of the valve of  FIG. 4A  and its pump rotor passageway. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0017]    The disclosure provided in the following pages describes examples of some embodiments of the invention. The designs, figures, and description are non-limiting examples of certain embodiments of the invention. For example, other embodiments of the disclosed device may or may not include the features described herein. Moreover, disclosed advantages and benefits may apply to only certain embodiments of the invention and should not be used to limit the disclosed invention. 
         [0018]    To the extent parts, components and functions of the described invention provide for exchange fluids, the suggested interconnections and couplings may be direct or indirect unless explicitly described as being limited to one or the other. Notably, indirectly connected parts, components and functions may have interposed devices and/or functions known to persons of ordinary skill in the art. 
         [0019]      FIG. 1  shows an embodiment of the invention  100  in the form of a schematic diagram. A spill or bypass valve  108  is interconnected with a pump  104  via a pump outlet  106 . The pump includes a pump inlet  102  and the valve includes a valve outlet  110  and a valve spill port  112 . In various embodiments, the inlets, outlets and ports are one or more of a fitting, flange, pipe, or similar fluid conveyance. 
         [0020]      FIG. 2A  shows a section of a typical downhole production string  200 A. The production string includes the bypass valve  108  interposed between the pump  104  and an upper tubing string  204 . In some embodiments, a casing  208  surrounds one or more of the tubing string, valve, and pump. Here, an annulus  206  is formed between the tubing string and the casing. A production flow is indicated by an arrow  102  while a backflow is indicated by an arrow  202 . In various embodiments, the bypass valve incorporates a spill port and in various embodiments the valve is operable to isolate backflows from one or more of the valve, portions of the valve, and the pump. 
         [0021]    Some embodiments of the production string include an extended tubular element  203  coupled with the upper tubing string  204 . For example, the extended tubular element may be a part of the valve or may be separate from the valve. In an embodiment, the extended tubular element is a valve body portion. The production may use a pump such as a rod driven pump with a pump drive rod  250  passing through the tubing string and interconnecting with the pump (pump interconnection is not shown). 
         [0022]      FIG. 2B  shows a cross-section A-A through the production string of  FIG. 2A . Clearance(s)  260  between the rod  250  and the extended tubular element  203  and clearance(s)  262  between the extended tubular element and the casing  208  are shown. In particular, clearance(s) between the rod and the extended tubular element may be chosen to guide the rod and as such may be less than similar clearance(s) associated with the upper tubing string. In some embodiments, guards or ribs mounted within the extended tubular element or to the rod provide stand-offs to guide the rod. 
         [0023]      FIGS. 3A-B  shows a schematic view of an end portion of a downhole production string assembly  300 A-B. The assembly includes a valve  108  interposed between a rod  250  driven pump  104  and a section of production tubing  204 . In some embodiments, a diverter valve with a rod mounted bobbin is used and in some embodiments, a progressive cavity pump is used. 
         [0024]    The pump  104  includes a pump rotor  276  having an outer periphery  284  and an outer diameter d 62  that may engage with a pump stator such as a surrounding pump stator  274 . Rotation of the pump rotor causes a fluid at the pump inlet  290  to be drawn into the pump and discharged into the valve  108 . 
         [0025]    During fluid production operation, the rod  250  turns the pump rotor  276  such that a fluid is drawn into the pump intake  290 , moves through the pump  104 , through the valve  108 , out of the valve  292 , and into the production tubing  282 . 
         [0026]    The valve  108  includes a bore or pump rotor passage  280  having a minimum diameter d 61  designed with a valve to rotor clearance c 61  that allows for passage of the pump rotor  276  having a diameter d 62  to pass through the valve. As used herein, bore refers to a passageway formed by any suitable method known to skilled artisans. 
         [0027]    During operations requiring pump rotor  276  relocation, the rod  250  which is coupled to the pump rotor is used to move the rotor through the production string components. For example, during installation, the rotor is lowered on the rod through the production tubing  204 , through the valve rotor passage  280 , and into the pump stator  274 . 
         [0028]      FIGS. 4A-H  show valve embodiments that include a pump rotor passage  400 A-H. 
         [0029]      FIG. 4A  shows diverter valve with a bobbin incorporated in a downhole production string assembly with a rod driven pump.  FIG. 4B  shows an enlarged middle portion of the valve of FIG. A in the bobbin up configuration.  FIG. 4C  shows the enlarged middle portion of the valve of FIG. A when the bobbin is down  400 C. As seen in the figures, a valve body  402  includes an upper body or stand-off  404 , a middle body  405 , and a lower body  406 . 
         [0030]    In the embodiment of  FIG. 4A , a valve  401  has a valve body  402  that extends between upper  403  and lower  407  adapters. In various embodiments, valve sizes include but are not limited to 2⅜ inch, 2⅞ inch, and 3½ inch. The lower adapter is coupled with a rod driven pump  445 , such as a progressive cavity pump, having a pump rotor  256  with a maximum outer diameter d 72  that is inserted in a pump stator  254 . In some embodiments, the pump is directly connected with the valve or a lower adapter and, in some embodiments, an optional pump connector spool  447  is interposed between the pump and the lower adapter (as shown). 
         [0031]    The upper body includes a first through hole  469 . In some embodiments, the first through hole passes through an outlet chamber  465  of an upper adapter  403 . And, in some embodiments, an inner surface of the adapter  467  is threaded. As used herein, the phrase through hole indicates a thru-hole passage. And, as persons of ordinary skill in the art will recognize, embodiments may have a through hole with a constant cross-section or a through hole of varying shape and/or cross-section as shown here. Embodiments of the adapter block a bobbin  411  from leaving the upper body  404 . In an embodiment, the bobbin is in slidable contact with a polished rod portion  419 , for example to reduce bobbin-rod friction to bobbin sliding. 
         [0032]    The middle body includes a second through hole  471 . In various embodiments, the second through hole provides or adjoins a shuttle chamber  461  and fluidly couples the valve outlet chamber  465  with a valve inlet chamber  464 . The lower body includes a third through hole  473 . In various embodiments, the third through hole passes through the inlet chamber  464 . As used herein, the term couple refers to a connection that is either of a direct connection or an indirect connection that may further include interposed components. 
         [0033]    Within the lower body  406 , a spring shoulder such as an annular spring shoulder  444  for supporting a charge spring  408  projects inwardly from a first inner bore of the lower body  472 . In some embodiments, the shoulder extends between the first inner bore of the lower body and a cylindrical spring guide  442 . 
         [0034]    And, in some embodiments, the shoulder  444  and the spring guide  442  are portions of a lower adapter  407  forming at least part of the lower body  406 . In various embodiments, an upper end of the adapter  474  has a reduced outer diameter  476  such that the spring shoulder is formed where the diameter is reduced and the spring guide is formed along the length of the reduced diameter portion of the adapter. As shown, portions of the charge spring  408  are located in an annular pocket  463  between the first inner bore of the lower body  472  and the spring guide. The adapter and lower body may be integral or fitted together as by a threaded connection  446  or another connection known to a skilled artisan. 
         [0035]    In some embodiments, a spring guide port  456  provides a means for flushing the annular spring pocket  463 . As seen, the port extends between the lower chamber  464  and the annular pocket  463 . Action of the charge spring  408  and/or pressure differentials between the pocket and the lower chamber provide a flushing action operative to remove solids such as sand that may otherwise tend to accumulate in the annular pocket. 
         [0036]    Within the middle body  405 , a middle body bore  438  is for receiving a valve shuttle  410 . The charge spring  408  is for urging the shuttle toward the valve outlet end  499 . This shuttle urging may be via direct or indirect charge spring contact. For example, embodiments utilize direct contact between a shuttle lower end  421  and an upper end of the charge spring  478 . Other embodiments utilize indirect contact such as via an annular transition ring  423  having an upper face  493  contacting the shuttle carrier lower end and a lower face  425  contacting a charge spring upper end (as shown). 
         [0037]    Near a lower end of the upper body  475 , an inwardly projecting nose  430  includes a stationery seat  432  for engaging a closure  414  encircling a shuttle upper end  413 . In various embodiments, the shuttle has a tapered upper end  417  and the closure is part of or extends from this taper. In various embodiments the seat and closure are configured to meet along a line forming an angle θ&lt;90 degrees with respect to a valve centerline y-y. Absent greater opposing forces, the charge spring  408  moves the shuttle  410  until the shuttle closure  414  is stopped against the stationery seat  432  to form a first seal  431 . 
         [0038]    The rod driven valve includes a central, rotatable, pump driving rod. The rod section shown is a lower rod section  409  with a central axis about centered on the valve centerline y-y. Not shown is this or another rod section&#39;s interface with a pump or an upper rod portion that is coupled to a rotating drive means. 
         [0039]    The lower pump driving rod  409  passes through the valve body  402 . In particular the rod passes through the first through hole  469 , through the shuttle bore  452 , and through the third through hole  473 . Like the valve of  FIG. 3A , the valve of  FIG. 4A  has a part dragged by fluid flow, the bobbin  411 . The bobbin is slidably mounted on the rod above the shuttle as shown in  FIG. 4A . The bobbin has a mounting hole for receiving the rod. Bobbin shapes include fluid-dynamic shapes suitable for utilizing drag forces operable to lift the bobbin when there is sufficient forward flow  488 . For example, the bobbin may be shaped with substantially conical ends (as shown). 
         [0040]    In an embodiment, the bobbin  411  includes a bobbin body  420  with a through hole  418  and a peripheral groove  412  defining a plane about perpendicular to the valve y-y axis. The groove is for receiving a bobbin ring  413  and the bobbin ring is for sealing a shuttle mouth  461 . In various embodiments, the bobbin body is made from polymers such as plastics and from metals such as stainless steel. And, in various embodiments, the bobbin ring is made from polymers such as plastics and from metals such as stainless steel. 
         [0041]    In some embodiments, the bobbin body  420  and ring  413  are integral and in some embodiments the bobbin has a bobbin hole insert (not shown) that is made from a material that differs from that of the bobbin body, for example, a metallic insert fitted into an outer plastic body. And, in an embodiment, the bobbin body is injection molded and a metallic bobbin ring is included in the mold during the injection molding process. 
         [0042]    As further explained below, the bobbin  411  moves along the rod  409  in response to flow through the valve, rising above the shuttle  410  when there is sufficient forward flow  488 , and falling to mate with the shuttle when there is insufficient forward flow and when there is reverse flow  489 . See also the perspective cutaway view of a similar valve  400 H of  FIG. 4H . 
         [0043]      FIGS. 4D-E  show the shuttle in a compressed spring position  400 D-E. Unlike  FIGS. 4A and 4B  showing a normal forward flow  488  through the valve  401  with the shuttle stationery seat  432  and closure  414  mated,  FIGS. 4D-E  show the shuttle  410  separated from the closure  414  during a reverse flow  489 , the charge spring  408  being compressed by movement of the shuttle toward the valve inlet end  498 . Notably, one or more sliding seals about the shuttle provide a sliding seal  435  between the shuttle  410  and a middle body bore mated with the shuttle such as the middle body bore  438 . 
         [0044]    When there is sufficient forward flow  488  through the valve  400 B, flow through the shuttle bore  452  lifts the bobbin  411  above the shuttle  410  and the charge spring  408  holds the shuttle against the valve body protruding nose  430 . With the bobbin lifted above the shuttle, flow passes freely through the shuttle bore and into the valve outlet chamber  465 . 
         [0045]      FIG. 4F  shows a valve embodiment similar to the valve of  FIG. 4A  with an upper body  404  having a length l 1 . Here, an upper adapter  403  is configured, as by guards, spokes, annular obstructions or the like, to stop the bobbin from rising beyond the upper adapter. In various applications, a suitable length l 1  may depend upon factors such as fluid viscosity, bobbin geometry, fluid flow rate ranges, and spacing between the bobbin and surrounding structures. In some embodiments, length l 1  for 4 and 6 inch valve sizes is in the range of about 2 to 10 feet. And, in some embodiments, length l 1  is in the range of about 4 to 20 times the valve size. Skilled artisans may utilize knowledge of the application and its constraints such as fluid properties to select suitable geometric variables including length l 1 . 
         [0046]    In an embodiment, the upper body  404  or an extension thereof functions as a flow tube having an internal diameter (FTID) that is greater than the internal diameter of downstream production tubing  204  (PTID). Flow tube lengths may be 2-10 feet in some embodiments, 4-8 feet in some embodiments, and about 6 feet in some embodiments. 
         [0047]    For a given rate of fluid production, the flow tube feature provides for lower fluid velocity in the flow tube as compared with production tubing fluid velocity and for managing the operation and travel of the bobbin  411 . For example, as the ratio FTID/PTID increases, the likelihood of bobbin travel into the production tubing is reduced. And, for example, as the magnitude of FTID increases, the pump flowrate required to suspend the bobbin above the shuttle  410  increases. In various embodiments, the ratio FTID/PTID is in the range of 1.05 to 1.5 and in some embodiments, the ratio FTID/PDID is in the range of 1.1 to 1.3. As skilled artisans will appreciate, choosing this ratio depends, inter alfa, on fluid properties and transport conditions. 
         [0048]    Referring to  FIG. 4C  (see detail area  4 BA of  FIG. 4B ), the rising shuttle is stopped when the shuttle closure  414  mates with the stationery seat  432  forming the body-shuttle seal  431 . Forces acting on the bobbin  411  include drag forces due to flow through the shuttle bore  452  and gravitational forces. In various embodiments, when drag forces are overcome by gravitational forces due to insufficient forward flow, the bobbin falls relative to the shuttle  410 . 
         [0049]    Notably, during an inadequate flow event, the bobbin  411  falls relative to the shuttle  410  (see  FIG. 4E  and detail area  4 CA of  FIG. 4D ), On shuttle contact, the bobbin ring closure  480  comes to rest against a shuttle mouth seat  481  forming a shuttle-bobbin seal  482  and blocking flow through the shuttle. Pressure forces at the valve outlet P 22  act on the blocked shuttle and move it toward the valve inlet  498 , a process that compresses the charge spring  408 . When the bobbin ring closure and shuttle mouth seat are mated, forward flow is substantially limited. In some embodiments, flow is stopped but for leakage such as unintended leakage. 
         [0050]    As seen, to the extent that the fluid head at the valve outlet P 22  results in a fluid head force on the shuttle sufficient to overcome resisting forces including compressing the charge spring  408 , the shuttle  410  moves toward the inlet end of the valve  498 . In various embodiments, a shuttle diameter  437 , approximated in some embodiments as a middle body bore diameter  439 , provides an estimate of the area acted on by the fluid head and thus the fluid head force. Skilled artisans will adjust valve performance by determining valve variables including a spring constant “k” (F=k*x) of the charge spring to adapt the valve for particular applications. 
         [0051]    Turning now to the spill port  428 , it is seen that forward flow  488  and the body-shuttle seal  431  associated with forward flow enable blocking of the spill port  428 . For example, the spill port may be blocked by forming an isolation chamber and/or by isolating or sealing the port  493 . When the spill port is blocked, flow entering the valve inlet  498  passes through the shuttle through bore  452 , out a shuttle mouth  461 , into the valve outlet chamber  465 , and out of the valve outlet  499 . 
         [0052]    Referring to  FIGS. 4D , it is seen that reverse flow  489  and the shuttle-bobbin seal  482  (see also  FIG. 4E ) associated with reverse flow enable opening of the spill port  428  as the shuttle  410  moves toward the inlet end of the valve  498  and the upper seal  431  is opened. When the shuttle-bobbin seal is closed, flow through the shuttle is blocked and a sliding shuttle-bore seal  435  blocks flow between the shuttle and the middle body bore  438 . However, the shuttle-body seal  431  is now open and reverse flow entering the valve can pass around the nose  479  and leave the valve  416  via the spill port  428 . 
         [0053]    In some embodiments, reverse flow  489  and/or an adverse pressure gradient (outlet pressure P 22 &gt;inlet pressure P 11 ) move the shuttle  410  toward the valve inlet end  498  by a distance within dimension S 11 . This shuttle stroke unblocks the spill port  428  allowing flow entering the outlet chamber  489  to move through a spill pocket  484  with boundaries including the middle body bore  438  and the shuttle  410  before exiting the valve body  416  via one or more spill ports  428 . And, in some embodiments, the illustrated spill port is one of a plurality of spill ports arranged around a valve body periphery  486 . 
         [0054]    The shuttle  410  of the valve  401  has a periphery  437  that seals, at least in part, against an internal bore of the valve such as the middle body bore  438 . While some embodiments provide a shuttle with a substantially continuous sealing surface (as shown) for providing a sliding seal  435 , various other embodiments provide a discontinuous sealing surface. For example, seals in the form of raised surface portions, rings in groves, snap rings, O-rings, and other suitable sealing parts and assemblies known to skilled artisans may be used. 
         [0055]      FIG. 4G  shows a schematic outline of a valve rotor passage  400 G. In particular, the figure illustrates a valve rotor passage for an end portion of a downhole production string assembly such as that of  FIG. 4A . 
         [0056]    In the figure, the dashed cylindrical space indicates a passageway  4002  of minimum diameter d 71  extending from the pump  445  and/or pump coupling spool  447  (see  FIG. 4A ) and through the valve  401  into the production tubing  204  (See  FIG. 2A ). The pump rotor  256  has a maximum outside diameter for passage d 72  such that when the rotor and passageway are coaxially arranged, a clearance c 71  exists between the rotor and the passageway (i.e., d 71 &gt;d 72 ). 
         [0057]    In various embodiments, the clearance c 71  may be referred to as or in connection with drift and may be in the range of 10 to 100 thousandths of an inch and in some embodiments in the range of 20 to 30 thousandths of an inch. 
         [0058]    Some embodiments provide a valve  401  bore that is full drifting of production tubing  204  size. That is, the valve provides a passageway that is at least as large as that of the production tubing such that, for example, a pump rotor  256  able to pass through the production tubing is also able to pass through the valve. 
         [0059]    In an embodiment, a valve portion of the passageway  4002  is defined by i) a valve upper body  404  with a valve upper body bore  429  that is equal to or greater than d 71 , a valve middle body  405  with a valve middle body nose  430  and nose bore  459  that is equal to or greater than d 71 , and a valve lower body  406  with a valve lower body bore that is equal to or greater than d 71 . 
         [0060]    In an embodiment, a valve outlet portion of the passageway  4002  is defined by a valve upper adapter  403  having a valve upper adapter bore  427  that is equal to or greater than d 71  and production tubing  204  having a production tubing bore  229  that is equal to or greater than d 71 . 
         [0061]    In an embodiment, a valve inlet portion of the passageway  4002  is defined by a valve lower adapter  407  having a valve lower adapter bore  449  that is equal to or greater than d 71  and/or a pump connector spool  447  with a pump connector spool bore  457  that is equal to or greater than d 71 . 
         [0062]      FIGS. 5A-B  provide flowcharts illustrating exemplary operating scenarios of selected embodiments of the invention  500 A-B. 
         [0063]      FIG. 5A  shows a sequence of steps for production facility installation, for example, steps for one of a new installation or an installation following a rework including removal of production tubing. 
         [0064]    First, a stator lowering assembly is assembled and installed as seen in steps  1 - 4  of  FIG. 5A . 
         [0065]    In a step numbered  1 , a pump stator (see e.g.,  254 ,  274 ) and a spool (see e.g.,  447 ) are coupled together. In a step numbered  2 , a valve (see e.g.,  108 ,  401 ) is coupled to the free end of the spool. In a step numbered  3 , production tubing (see e.g.,  204 ) is coupled to the free end of the valve. In a step numbered  4 , the stator assembly, stator first, is lowered downhole. As needed, production tubing is added to the production tubing string until sufficient production tubing has been added to reach the desired depth, typically when the pump stator is submersed in reservoir zone that is or will be flooded with liquid. Note that in some embodiments, there is no spool such that the stator and production tubing are coupled together without a spool. 
         [0066]    Second, a rotor lowering assembly is assembled and installed as seen in steps  5 - 8  of  FIG. 5A . 
         [0067]    In a step numbered  5 , a pump rotor (see e.g.,  256 ,  276 ) and a polished portion of pump driving rod (see e.g.,  419 ) are coupled together and a bobbin or valve actuator (see e.g.,  411 ) is installed on the rod. In a step numbered  6 , the rotor assembly is inserted in the free end of the production tubing (see e.g.,  204 ) and lowered downhole. Pump driving rod is added to the drive rod string as needed until the rotor meets and is inserted in the stator (see e.g.,  274 ). In a step numbered  7 , the pump rotor is spaced according to the pump manufacturer&#39;s specification. In a step numbered  8 , in preparation for the beginning of production of liquids from the reservoir to the surface, the pump drive rod is readied for rotation and then rotated to operate the pump. 
         [0068]      FIG. 5B  shows a sequence of steps for production facility equipment removal and installation, for example, steps taken when the pump rotor must be replaced. 
         [0069]    First, the pump rotor is lifted to the surface as seen in steps  1 - 2  of  FIG. 5B . 
         [0070]    In a step numbered  1 , the pump drive rod rotation is stopped and preparations are made to pull the rod (see e.g.,  409 ) to the surface. In a step numbered  2 , the rod is lifted with the attached rotor (see e.g.,  256 ,  276 ) until the rotor reaches the surface. 
         [0071]    Second, a rotor lowering assembly is assembled and installed as seen in steps  3 - 6  of  FIG. 5B . 
         [0072]    In a step numbered  3 , a new/renewed pump rotor (see e.g.,  256 ,  276 ) and a polished portion of pump driving rod (see e.g.,  419 ) are coupled together and a bobbin or valve actuator (see e.g.,  411 ) is installed on the rod. In a step numbered  4 , the rotor assembly is inserted in the free end of the production tubing (see e.g.,  204 ) and lowered downhole. Pump driving rod is added to the drive rod string as needed until the rotor meets and is inserted in the stator (see e.g.,  274 ). In a step numbered  5 , the pump rotor is spaced according to the pump manufacturer&#39;s specification. In a step numbered  6 , in preparation for the beginning of production of liquids from the reservoir to the surface, the pump drive rod is readied for rotation and then rotated to operate the pump. 
         [0073]    The present invention has been disclosed in the form of exemplary embodiments. However, it should not be limited to these embodiments. Rather, the present invention should be limited only by the claims which follow where the terms of the claims are given the meaning a person of ordinary skill in the art would find them to have.