Patent Publication Number: US-10777935-B2

Title: Pothead retaining sleeve system, apparatus and method

Description:
BACKGROUND 
     1. Field of the Invention 
     Embodiments of the invention described herein pertain to the field of electric submersible motor power cable connections. More particularly, but not by way of limitation, one or more embodiments of the invention enable a pothead retaining sleeve system, apparatus and method. 
     2. Description of the Related Art 
     Fluid, such as natural gas, oil or water, is often located in underground formations. When pressure within a well is not enough to force fluid out of the well, the fluid must be pumped to the surface so that it can be collected, separated, refined, distributed and/or sold. Centrifugal pumps are typically used in electric submersible pump (ESP) applications for lifting well fluid to the surface. Centrifugal pumps accelerate a working fluid through a rotating impeller, which is driven by a rotating shaft. 
     The shaft&#39;s rotation is powered by an electrical motor typically located on an upstream side of a pump assembly. The motor is conventionally a two-pole, three-phase squirrel cage induction motor. The ESP power source is located at the surface of the well and is connected to the motor by insulated electrical conductors that extend up to thousands of feet alongside the ESP assembly down into the wellbore. A motor lead extension (MLE) cable, also referred to as a motor flat, is a low-profile cable that is spliced to the lower end of the main power cable, banded to the side of the ESP pump and seal-chamber section, and has a male termination for plugging or splicing into the motor electrical connection. An MLE typically has three leads or “phases.” At a connection point to the motor, the MLE phases extend through a protected electrical connector that engages with an electrical receptacle on the motor. The electrical connector is sometimes referred to in the art as a “pothead,” named after the potted or encapsulated conductors inside the electrical connector. 
     Well fluid should not contact the motor&#39;s electrical cables or electrical connections to avoid failure of the cables providing power to the motor. Failure of the power cables may cause inadequate power to the motor and failure of the motor. A conventional pothead includes a corrosion-resistant steel body filled with a number of insulating materials used within, including, for example, Polyether Ether Ketone (PEEK), an opaque organic thermoplastic polymer, which insulates the motor&#39;s electrical connections.  FIG. 1  illustrates a cross section of a pothead of the prior art. Conventional pothead  100  may be made of lead in order to prevent harmful gas such as H 2 S from permeating into motor electrical connections inside conventional pothead  100 . Three conventional phases  105  are typically arranged inside conventional pothead  100 . In any typical configuration, a conventional insulator  110  surrounds the phases to provide electrical integrity. 
     To install the power cable to the motor, the installer plugs each MLE phase into the connectors of the motor head, metal to metal. Next, the installer typically seals the connectors with insulating material such as polytetrafluoroethylene (PTFE) or the polyimide tape known as Kapton® (a registered trademark of E. I. du Pont de Nemours and Company of the United States). Finally, the installer pushes the connectors into the motor head and seals the connection. The installer inserts the ESP motor cables into conventional pothead  100  by pushing each conventional phase  105 , one at a time, into conventional insulator  110  in conventional pothead  100 . To make this process easier, pothead conventional insulator  110  has a conventional retaining sleeve  115  for each conventional phase  105 . In addition to its insulating properties, conventional retaining sleeve  115  must be rigid to aid in pushing the phase connectors into the motor head. 
     While various embodiments of potheads offer different configurations for the three phases, all suffer from a lack of space between the respective retaining sleeves for the installer to connect and tape the phases. The space between the phases is at a premium and restricted to accommodate the size of the motor head and the size of the power cable, which is often limited by the size of the annulus surrounding the assembly. Further, at the end of the pothead installation process the installer must gather the phases together and wrap them in additional insulation to save space and form a single MLE. Therefore, the retaining sleeves must be very close together. Unfortunately, this results in the space between each sleeve being inadequate to allow for properly tying-off each phase. In an attempt to work around this problem, installers tend to bend the sleeves to the side, two at a time, to have room to tie off each phase. However, bending the phases in this manner creates stress points  120  in the insulators as shown in  FIG. 1 . Stress points  120  due to bending the rigid retaining sleeves create a potential for cracking, eventual cable damage and even cable failure over time. Where damage occurs to the insulator, the electrical connectors may be left vulnerable to ingress of unwanted fluids. Stress points  120  are particularly troublesome with multi-wire cable bundles. 
     As is apparent from the above, current electrical pothead connections do not provide sufficient space for an installer to tie-off the motor phases without risk of stress and/or damage to the phases and pothead insulator. Therefore, there is a need for an improved pothead retaining sleeve system, apparatus and method. 
     SUMMARY 
     A pothead retaining sleeve apparatus, system and method is described. Illustrative embodiments generally relate to a pothead pivoting retaining sleeve. 
     An illustrative embodiment of an electric submersible motor pothead includes a pair of insulating blocks including a first insulating block adjacent to a second insulating block, each pair of insulating blocks including a conduit for each phase of a plurality of phases of a power cable, each conduit including a socket formed partially by the first insulating block and partially by the second insulating block, a phase retaining sleeve extending through each conduit, the phase retaining sleeve including a ball seated in the socket and the phase retaining sleeve pivotable in the socket around the ball. In some embodiments, the phase retaining sleeve is pivotable by pitch, yaw and roll around the ball. In certain embodiments, the phase retaining sleeve further includes a tubular portion coupled to the ball, and a channel extending through the ball and the tubular portion of the retaining sleeve. In some embodiments, a power cable phase of the plurality of phases extends through the channel, the power cable phase powering an electric submersible motor. In some embodiments, the channel at a top of the ball includes a cutout around the power cable phase. In certain embodiments, each conduit further includes a tolerance extending from the socket, the tolerance accommodating angling of the phase retaining sleeve inside the pair of insulating blocks. In some embodiments, the tolerance includes a flared inner diameter of one of the first insulating block or the second insulating block. In certain embodiments, the tolerance includes a space around a tubular portion of the retaining sleeve. In some embodiments, each phase retaining sleeve is independently pivotable. In certain embodiments, the conduits are arranged in a triangular configuration and the pair of insulating blocks are round in cross-section. In some embodiments, the electric submersible motor pothead further includes a pothead housing, the pothead housing including a seal skirt extending below the pair of insulating blocks. In certain embodiments, the conduits are arranged in a side-by-side configuration and the pair of insulating blocks are elliptical. 
     An illustrative embodiment of an electric submersible motor pothead includes a plurality of pivotable retaining sleeves, each pivotable retaining sleeve of the plurality of pivoting retaining sleeves including a ball that seats within a socket inside the electric submersible motor pothead, the ball rotatable in the socket such that each pivotable retaining sleeve is independently moveable around a spheroidal joint formed by the ball and socket. In some embodiments, each pivotable retaining sleeve of the plurality of pivoting retaining sleeves further includes a tubular portion coupled to the ball, and a channel extending through an inside of the tubular portion and the ball, wherein a phase of a power cable extends through the channel before connecting to an electric submersible motor. In certain embodiments, the channel extending through the ball includes an outwardly extending cutout forming a clearance for the phase as the ball rotates in the socket. In some embodiments, there are three phases connected to the electric submersible motor and three pivotable retaining sleeves in the plurality of pivotable retaining sleeves. In certain embodiments, the socket is formed by at least one block inside a housing of the pothead, wherein phases of a power cable extend through conduits in the block. In certain embodiments, each socket forms a portion of the conduit. In some embodiments, the at least one block is made of an insulating material. In some embodiments, the at least one block is made of a steel. In certain embodiments, there are at least two blocks aligned to form each conduit, and each of the at least two blocks forms a portion of the socket. 
     An illustrative embodiment of an electric submersible motor pothead includes a pothead for electrically connecting a power cable to an electric submersible motor, the power cable including a plurality of phases, each phase of the plurality of phases extending through a retaining sleeve, the retaining sleeve extending through a conduit formed through an insulating block secured inside the pothead, the conduit including a substantially spherical socket, the retaining sleeve including a tubular portion and a ball at an end of the tubular portion, the ball seated within the substantially spherical socket to form a ball and socket joint, and the tubular portion rotatable inward and outward around the ball and socket joint during tying off of the plurality of phases. In some embodiments, each phase of the power cable includes a conductor surrounded by a cable insulation layer, wherein the conductor is electrically coupled to a conducting pin that plugs into an electric submersible motor. In certain embodiments, the electric submersible motor is downhole and is operable to turn an electric submersible pump, and wherein the power cable extends from a power source proximate a well surface to the electric submersible motor to provide power to the electric submersible motor. In some embodiments, the ball is a spherical segment, and the socket is rounded to mate with the spherical segment. In certain embodiments, a diameter of the spherical segment is larger than a diameter of the tubular portion. In some embodiments, wherein a ratio of the diameter of the spherical segment to the diameter of the tubular portion is 1.23:1 and the retaining sleeve is rotatable outwards up to 35°. 
     An illustrative embodiment of an electric submersible motor power cable insulating apparatus, the insulating apparatus fitting within a pothead, the apparatus including a plurality of pivoting insulating sleeves, each pivoting insulating sleeve including an axially oriented shaft for accepting a power cable phase of an electric submersible pump (ESP) power cable, includes a ball joint terminating one end of the axially oriented shaft, and a central conduit traversing the length of the axially oriented shaft and ball joint, the central conduit mateable with the power cable phase, a first insulating block having a plurality of pathway openings on a first face, each opening accommodating a pivoting insulating sleeve, and a second face opposite the first face, the second face including a portion of a spherical cavity accommodating a portion of the ball joint, the opening contiguous with the portion of the spherical cavity of the first insulating block to form a pathway through the first insulating block, and a second insulating block having a first face including a cable access opening accessing the pathway through the first insulating block and a second face opposite the first face, the second face including a portion of the spherical cavity that accommodates a remaining portion of the ball joint such that when the second face of the first insulating block and the second face of the second insulating block are joined, the two second faces form a spherical cavity mateable to the ball joint of the pivoting insulating sleeve. In some embodiments, each pivoting retaining sleeve rotates up to 35° from a longitudinal axis of the pothead within the pathway opening. In certain embodiments, the pathway opening is tapered. 
     An illustrative embodiment of a method of installing a three-phase power cable into an electric submersible pump (ESP) motor head, includes splicing the three-phase power cable to expose three separate phases, placing a terminating end of each phase, one at a time, into a central conduit of an upper insulator within a pothead, passing the each phase, one at a time, through a ball joint at one end of a pivoting retaining sleeve and continuing on through an axial portion of the pivoting retaining sleeve thereby passing through a lower insulator, creating a space to connect the terminating end of a first phase of the three separate phases to a terminal connector of the ESP motor head by bending the terminating ends of a second and third phase away from the first phase by pivoting the pivoting retaining sleeve up to 35° from a central axis passing through the center of the pivoting retaining sleeve, connecting the terminating end of the first phase to a terminal connector of the ESP motor head, tying the terminating end of the first phase to the terminal connector of the ESP motor head by wrapping the connection in insulating material, repeating creating a space, connecting and tying the terminating end steps for each of the second and third phases in turn until all three phases are tied to the ESP motor head, pushing the pothead into the motor head, and sealing the pothead to motor head connection. 
     In further embodiments, features from specific embodiments may be combined with features from other embodiments. For example, features from one embodiment may be combined with features from any of the other embodiments. In further embodiments, additional features may be added to the specific embodiments described herein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Advantages of the present invention may become apparent to those skilled in the art with the benefit of the following detailed description and upon reference to the accompanying drawings in which: 
         FIG. 1  illustrates a cross-sectional view of a traditional insulator and prior art retaining sleeve of a conventional pothead. 
         FIG. 2A  is a cross-sectional view across line  2 A- 2 A of  FIG. 12  of an exemplary pothead assembly showing pivoting retaining sleeves of an illustrative embodiment in a round configuration. 
         FIG. 2B  is a cross-sectional view across line  2 B- 2 B of  FIG. 13  of an exemplary pothead assembly showing pivoting retaining sleeves of an illustrative embodiment pivoted outward. 
         FIGS. 3A and 3B  are cross-sectional views of an exemplary pothead assembly showing pivoting retaining sleeves of an illustrative embodiment in a side-by-side configuration. 
         FIG. 4A  illustrates a side view of a pivoting retaining sleeve of an illustrative embodiment. 
         FIG. 4B  illustrates an orthogonal view of a pivoting retaining sleeve of an illustrative embodiment. 
         FIG. 4C  is a cross sectional view across line  4 C- 4 C of  FIG. 4A  of a pivoting retaining sleeve of an illustrative embodiment. 
         FIG. 5  illustrates a cross-sectional view across line  5 - 5  of  FIG. 18  of a pothead assembly of illustrative embodiments including an exemplary cable phase and terminal pin. 
         FIG. 6  illustrates a perspective view of a lower insulator having ball joint sockets of an illustrative embodiment. 
         FIG. 7  illustrates an exploded view of a pothead assembly with three pivoting retaining sleeves of an illustrative embodiment. 
         FIG. 8  illustrates a perspective view of a plurality of pivoting retaining sleeves installed in a lower insulator of an illustrative embodiment. 
         FIG. 9  illustrates a perspective view of placement of an upper insulator over a plurality of pivoting retaining sleeves of an illustrative embodiment. 
         FIG. 10  illustrates a perspective view of a plurality of pivoting retaining sleeves extending through an upper and lower insulator of an illustrative embodiment. 
         FIG. 11  illustrates a bottom view of a plurality of pivoting retaining sleeves encapsulated within an upper and lower insulator of an illustrative embodiment. 
         FIG. 12  illustrates an orthogonal view of a pothead assembly with three pivoting retaining sleeves of an illustrative embodiment in a round configuration. 
         FIG. 13  illustrates a bottom view of a pothead assembly with three retaining sleeves pivoted outward in an illustrative embodiment. 
         FIG. 14  illustrates an orthogonal view of a pothead assembly with all three retaining sleeves pivoted inward in an illustrative embodiment. 
         FIG. 15A-15B  illustrate a pothead housing of an illustrative embodiment for a side-by-side configuration of phases. 
         FIGS. 16A and 16B  illustrate a cross-section of an exemplary pothead assembly showing a pivoting retaining sleeve with a cable and terminal pin of an illustrative embodiment. 
         FIGS. 17A-17B  are perspective views of a pothead of an illustrative embodiment being installed into a motor head. 
         FIG. 18  illustrates a planar view of a pothead assembly with terminal pins of an illustrative embodiment. 
         FIG. 19  is a perspective view of an electric submersible pump (ESP) assembly employing a pothead of an illustrative embodiment. 
     
    
    
     While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and may herein be described in detail. The drawings may not be to scale. It should be understood, however, that the embodiments described herein and shown in the drawings are not intended to limit the invention to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the scope of the present invention as defined by the appended claims. 
     DETAILED DESCRIPTION 
     A pothead retaining sleeve apparatus, system and method are described. In the following exemplary description, numerous specific details are set forth in order to provide a more thorough understanding of embodiments of the invention. It will be apparent, however, to an artisan of ordinary skill that the present invention may be practiced without incorporating all aspects of the specific details described herein. In other instances, specific features, quantities, or measurements well known to those of ordinary skill in the art have not been described in detail so as not to obscure the invention. Readers should note that although examples of the invention are set forth herein, the claims, and the full scope of any equivalents, are what define the metes and bounds of the invention. 
     As used in this specification and the appended claims, the singular forms “a”, “an” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to a retaining sleeve includes one or more retaining sleeves. 
     “Coupled” refers to either a direct connection or an indirect connection (e.g., at least one intervening connection) between one or more objects or components. The phrase “directly attached” means a direct connection between objects or components. 
     “Downstream” refers to the longitudinal direction with the principal flow of lifted fluid through the wellbore when the pump assembly is in operation. By way of example but not limitation, in a vertical downhole electric submersible motor, the downstream direction may be towards the surface of the well. 
     “Upstream” refers to the longitudinal direction opposite the principal flow of lifted fluid through the wellbore when the pump assembly is in operation. By way of example but not limitation, in a vertical downhole electric submersible motor, the upstream direction may be opposite the surface of the well. 
     As used in this specification and the appended claims, with respect to a pothead assembly, the “bottom” of the pothead or a pothead component means the side of the pothead or pothead component closest to the motor when the pothead is installed, without regard to whether the well in which the pothead is installed is vertical, horizontal or extends through a radius. 
     As used in this specification and the appended claims, with respect to a pothead assembly, the “top” of the pothead or a pothead component means the side of the pothead or pothead component opposite the bottom of such pothead or pothead component. 
     As used herein, the term “outer,” “outside” or “outward” means the radial direction away from the center of an electric submersible pump (ESP) power cable phase and/or the opening of a component through which the phase would extend. In the art, “outer diameter” and “outer circumference” are sometimes used equivalently. As used herein, the term outer diameter is used to describe what might otherwise be called the outer circumference or outer surface of a pothead component such as a retaining sleeve or insulator block. 
     As used herein, the term “inner”, “inside” or “inward” means the radial direction toward the center of the ESP power cable phase and/or the opening of a component through which the phase would extend. In the art, “inner diameter” and “inner circumference” are sometimes used equivalently. As used herein, the term inner diameter is used to describe what might otherwise be called the inner circumference or inner surface of a pothead component such as a pothead housing or seal skirt, or the inner surface that forms a conduit through an insulating block. 
     As used herein the terms “axial”, “axially”, “longitudinal” and “longitudinally” refer interchangeably to the direction extending along the length of a pothead from bottom to top, or vice versa. 
     As used in this specification and the appended claims, “insulator block” or “insulating block” refer interchangeably to a block inside a pothead housing that surrounds the electrical connections&#39; retaining sleeves inside the pothead. Although conventionally the “insulator block” or “insulating block” would have been made of an insulating material such as rubber or polyether ether ketone (PEEK), illustrative embodiments are not so limited and include an insulator block or insulating block made of corrosion resistant steel or another similar conductive material without regard to insulating properties. 
     For ease of description, the illustrative embodiments described herein are described in terms of an ESP assembly making use of a three-phase motor and power cable. However, the pothead of illustrative embodiments is not so limited and may be applied to any motor, with any number of phases, exposed to fluid and having a motor plug-in, splice-in, tape-in or similar electrical connection. For example, the retaining sleeve of the illustrative embodiments may be applied to submersible motors in axial-flow pumps, radial-flow pumps, mixed-flow pumps, horizontal surface pumps, and/or turbine regenerative type pumps and/or to electric motors operating other types of machines that may be submerged. 
     Illustrative embodiments provide a pivotable pothead retaining sleeve that terminates at a ball joint. Each retaining sleeve may be encased in a cylindrical space formed by an insulator, the space having a rounded socket. The ball joint of the retaining sleeve may rest in the socket. A power cable and/or power cable phase may extend through the retaining sleeve. The ball joint may pivot in the socket to permit the retaining sleeve to rotate and/or swivel around the ball joint without putting undesirable stress on the insulator or power cable. Illustrative embodiments may provide a pivoting retaining sleeve to improve installation of an ESP motor&#39;s electrical power without creating compressive force on the phases when an installer bends the phases to allow for proper tie-in. Illustrative embodiments may reduce or eliminate stress points and/or cracking of pothead insulation, which may reduce the instance of cable damage or failure. Illustrative embodiments may provide space and/or movement for an installer to tie-off the phases without risk of stress and/or damage to the phases and possibly cracking the insulators. 
     In a three-phase motor, such as an ESP induction motor, the three cable phases may be included in the pothead of one or more illustrative embodiments. For ease of description, the pothead of illustrative embodiments may be described in terms of enclosing three phases in either a side-by-side or round configuration, however, other configurations may be employed depending on the number and size of phases and space limitations. 
       FIG. 2A  and  FIG. 2B  illustrate a pothead with pivoting retaining sleeves of an illustrative embodiment arranged in a round phase configuration. Retaining sleeve  200  may be tubular in shape with ball  205  on the upper side of sleeve  200 . Ball  205  may generally be spherical in shape although ball  205  may not form a complete sphere, for example ball  205  may be a spherical segment, spheroid and/or ellipsoid. As shown in  FIG. 2A  and  FIG. 2B , ball  205  is a spherical segment, cut by a plane at its top to allow phase  500  (shown in  FIG. 5 ) to extend through ball  205 , and cut by a plane at its bottom so as to be continuous with tubular portion  400  (shown in  FIG. 4A ). Socket  210  may be a two-part socket formed partially by upper insulating block  215  and partially by lower insulating block  220 . Socket  210  may be a cavity generally spherical or ellipsoid in shape, but may not form a complete sphere and/or may be complementary to the shape of ball  205 . Ball  205  and socket  210  may mate and/or be complementary in shape such that rounded portion of ball  205  rocks within rounded socket  210  as retaining sleeve  200  pivots, rotates, rolls and/or moves in the joint. Ball  205  of retaining sleeve  200  may sit within socket  210  and be rotatable and/or pivotable inside socket  210  to form pivotable retaining sleeve  200 . 
     Housing  225  of pothead  250  may include seal skirt  230  that extends below lower insulating block  220 . Seal skirt  230  may seal the motor connection from fluid ingress. In  FIG. 2A , retaining sleeve  200  is shown parallel to longitudinal axis  255 . In  FIG. 2B , retaining sleeves  200  have been rotated outwards an angle θ around pivot point  235 . Ball  205  and socket  210  joint may allow rotation around three axes (pitch, yaw and roll) about the common pivot point  235 , although seal skirt  230  and/or lower insulating block  220  may restrict angle θ and/or the range of motion of retaining sleeve  200 . As shown in  FIG. 2B , seal skirt  230  may limit the rotation of retaining sleeve  200  inside socket  210  as retaining sleeve  200  rotates to abut the inner diameter of seal skirt  230  and/or the inner diameter of tolerance  240 . Tolerance  240  may be an outward flare of the inner diameter of the conduit through lower insulating block  220 , below socket  210 , that accommodates angling of retaining sleeve  200  as shown in  FIG. 2B . Screws  245  may compress upper insulating block  215  and lower insulating block  220  together. Upper insulating block  215  and/or lower insulating block  220  may be made of insulating material such as Polyether Ether Ketone (PEEK), rubber, ceramic, phenolic resin, thermal plastic or another similar insulating material. In some embodiments, upper insulating block  215  and/or lower insulating block  220  may be conductive and may be made of metal, such as steel. 
       FIG. 3A  and  FIG. 3B  illustrate a pothead with pivoting retaining sleeves of an illustrative embodiment showing a side-by-side (linear) phase configuration. Round and/or spherical socket  210  may be formed partially by upper insulating block  215  and partially by lower insulating block  220 . For example, each insulating block  215 ,  220  may form half of socket  210  and/or spherical socket  210  may be formed ⅓ by a first insulating block and ⅔ by the second block. In certain embodiments, socket  210  may be formed in a single insulating block. Ball  205  of retaining sleeve  200  seats within socket  210  and may be pivotable and/or rotatable therein. In the example of  FIG. 3A  and  FIG. 3B , lower insulator  220  extends beyond and/or below (lower than) pothead housing  225 , and the lower insulator  220  may limit the maximum angle θ of rotation of retaining sleeve  200 . A lead gasket  300  surrounded by an elastomeric boot  305 , which may be a molded seal made of rubber such as ethylene propylene diene monomer (EPDM) or Aflas® (a registered trademark of Asahi Glass Co. of Japan), may seal the space between the outer diameter of lower insulator  220  and the inner diameter of housing  225 . In  FIG. 3A , retaining sleeves  200  are parallel to longitudinal axis  255 . In  FIG. 3B , the retaining sleeve  200  has been rotated outward an angle θ. The side-by-side embodiment of  FIGS. 3A and 3B  may be compared and contrasted with the round and/or triangular embodiment shown in  FIGS. 2A and 2B . 
       FIGS. 4A-4C  illustrate a pivoting retaining sleeve of illustrative embodiments. Retaining sleeve  200  may generally be rigid and tubular in shape, and may be made of polyetheretherketone (PEEK), rubber, ceramic, phenolic, thermoplastic or another non-conductive material having similar properties. An end of sleeve  200  may include ball  205  that pivots within socket  210 , to form a ball and socket and/or spheroidal joint. The ball and socket joint may permit retaining sleeve  200  with phase  500  (shown in  FIG. 5 ) extending through retaining sleeve  200 , to pivot during installation of phases  500  and connection of pothead assembly  250  to motor head  1700  (shown in  FIG. 17A ). Tubular portion  400  (body) of pivotable retaining sleeve  200  may be about ¾ (or 75%) of the length of retaining sleeve  200 . Tubular portion  400  may be tubular, annular and/or shaped like a hollow cylinder. Ball joint  205  may form one end of pivoting retaining sleeve  200 . Ball  205  may be a rounded, ellipsoid and/or spherical bulb and/or protrusion at one end of retaining sleeve  200 . 
     Ball  205  may have a larger diameter than the diameter of tubular portion  400  such that ball  205  stays locked and/or does not slide out from socket  210 . The ratio of the diameter of ball  205 , the diameter of the sphere of which ball  205  forms a segment, and/or the largest diameter of ball  205  as compared to the diameter of tubular portion  400  may determine the angle, degrees and/or extent of pivot of retaining sleeve  200 . For example, to achieve a 35° cone  800  (shown in  FIG. 8 ) of movement, the ratio between the diameter of tubular portion to the diameter of ball  205  (e.g., the diameter of the sphere from which ball  205  is cut) is 1:1.23. 
     Axial opening  405  may extend the length of pivoting retaining sleeve  200  from tubular end  410  through ball  405 . Axial opening  405  may terminate in a similarly sized opening in the base of ball joint  205 , but include tapered cutout  415 , and permit phase  500  to extend through the length of retaining sleeve  200 . Illustrative embodiments may accommodate diameter variations in the power cables  1940  (shown in  FIG. 19 ) and phases  500 . Exemplary power cables  1940  of illustrative embodiments may vary from ⅛″ (3.175 mm) to ¼″ (6.35 mm), though illustrative embodiments are not so limited. Depending on the cable diameter, the diameter and/or thickness of the pivoting retaining sleeves  200  and their associated ball sockets  210  may vary to maximize effectiveness. In an exemplary, non-limiting example phase  500  may have a diameter of ¼ inch (6.35 mm), pivoting retaining sleeve ball  205  may have a radius of about 0.245″ (6.223 mm), and sleeve  200  may be about 1.260″ (3.2 cm) in length. In this example, pothead assembly  250  may be about 4.2 inches (10.668 cm) in length. 
     Ball  205  and/or axial opening  405  may include cutout  415 , as illustrated in  FIG. 4C . Cutout  415  may be a notch, angling outward and/or clearance around opening  405  extending through the top of ball  205 . Cutout  415  may ensure that as retaining sleeve  200  pivots with phase  500  extending through opening  415  of retaining sleeve  200 , retaining sleeve  200  does not cut into phase  500  and/or retaining sleeve does not otherwise damage phase  500 .  FIG. 5  illustrates a cross-sectional view of the pothead assembly  250  including phase  500  extending through pothead  250  and retaining sleeve  200 . Conductor  505  of phase  500  terminates at terminal pin  510 . Cable insulation  515  may terminate prior to terminal pin  510  to allow conductor  505  to contact terminal pin  510 . Cutout  415  provides a clearance around phase  500  as phase  500  extends through ball  205 , to permit retaining sleeve to rotate without piercing phase  500 . 
       FIG. 6  illustrates an orthogonal view of a pothead upper insulator showing ball joint sockets of an illustrative embodiment. Upper insulator  215  may have a variety of cross-sectional shapes such as elliptical or round. The portion of socket  210  formed by upper insulator  215  is shown. Apertures  600  may be for compression screws  245  to attach upper insulator  215  to lower insulator  220  when pothead  250  is assembled. In round phase  500  configurations, upper insulator  215  may have a circular or similarly rounded cross-section as shown in  FIG. 7 , for example. Whether sleeves  200  are in a round, side-by-side, or other configuration, retaining sleeves  200  of illustrative embodiments may operate in a substantially similar manner. As shown in  FIG. 7 , sockets  210  and/or conduits extending through upper insulating block  215  and lower insulating block  220  may extend through the insulating blocks  215 ,  220  from a first face through to the opposing face of each block  215 ,  220 . In  FIG. 8 , three pivoting retaining sleeves  200  are shown in a side-by-side configuration in an elliptically-shaped insulating block  215  that may be installed into pothead housing  225 . 
     Each phase  500  of a motor  1935  (shown in  FIG. 19 ) powered by cable  1940  may require one pivoting retaining sleeve  200 . Upper insulator  215  may have the rounded and/or spherical ball socket (cavity)  210  or a portion thereof for each of the pivoting retaining sleeves  200  as illustrated in  FIG. 8 . In some embodiments, for ease of illustration and so as not to obscure illustrative embodiments, this description assumes a three-phase embodiment, though illustrative embodiments are not so limited. Thus, upper insulator  215  of  FIG. 8  shows three ball sockets  210 . Each insulating block  215 ,  220  may form a portion, one-half, or about one-half the space that forms socket  210 , receives ball joint  205  and/or provides the common center  235  around which ball joint  205  may pivot. The other portion of socket  210  may be formed in lower insulator  220 . The ball sockets  210  in upper insulator  215 , lower insulator  220  and/or a combination thereof, are of largely identical and sufficient size to encompass ball joint  205 , with enough tolerance to allow ball joint  205  to rotate and/or pivot as described herein. 
       FIG. 8  illustrates three pivoting retaining sleeves  200  installed in upper insulator  215  of an illustrative embodiment. Central axis  255  may be a line parallel to the axial direction of the retaining sleeve  200  and/or the longitudinal direction through pothead  250 . Angle θ may indicate a cone  800  of rotation around central axis  255  with angle θ being an angle of offset from central axis  255 . Cone  800  may proscribe the degrees of freedom of each pivoting retaining sleeve  200 . Where tubular portion  400  of retaining sleeve  200  abuts lower insulating block  220  or skirt seal  230  when angled, angle θ may be about 20°, 30°, 35° or 40° from central axis  255 . Once positioned at about angle θ from central axis  255 , retaining sleeve  200  may pivot, rotate, and/or swivel along cone  800  and/or may be repositioned through yaw, pitch or roll, as needed. Each of the pivoting retaining sleeves  200  may rotate independently of one another, such that an installer may push two sleeves  200  in one direction and a third may be pulled in another, creating room for the installer to tie-in each phase  500  of power cable  1940  one phase  500  at a time. Sleeves  200  may move independently from one another, each sleeve  200  rotating in a distinct direction. 
       FIG. 9  illustrates placement and/or sliding of lower insulator  600  over a plurality of ball joint retaining sleeves  200 . Lower insulator  220  may have elongate openings  900  of sufficient diameter to accommodate retaining sleeve  200 , including pivoting of retaining sleeve as sleeve  200  leans in response to pivoting of ball joint  205 . In side-by-side embodiments with three phases  500 , the center retaining sleeve  200  may have an elongate opening  900  on each side and/or clearance  310  may extend between the inner diameter of lower insulating block  220  and the outer diameter of retaining sleeve  200 . Lower insulator  220  may also include ball socket  210 , the lower portion of ball socket  210  and/or a cylindrical opening terminating in a portion of ball socket  210 , to accommodate retaining sleeve  200  and/or the lower portion of ball joint  205 , with tolerances  240  to allow for independent rotation of each pivoting retaining sleeve  200  as described above. In some embodiments, elongate opening  900 , tolerance  240  and/or clearance  310  may taper outwards (flare) at about 35° to allow pivoting retaining sleeve  200  to rotate on ball joint  320  a sufficient angle θ without obstruction to create room for installation of phases  500  into motor head  1700 . 
       FIG. 10  illustrates a plurality of ball joint retaining sleeves  200  encapsulated within upper insulator  215  and lower insulator  220  of an illustrative embodiment. Retaining sleeves  200  may extend through conduits and/or pathways extending through insulators  215 ,  220 , and phases  500  may extend through retaining sleeves  200 . In this exemplar, all three pivoting retaining sleeves  200  may be parallel to central axis  255 . Tolerance  240  around each retaining sleeve  200  and/or adjacent to the bottom of socket  210  is shown in  FIG. 11 , which is a bottom view of lower insulator  220 . Tolerance  240  may permit retaining sleeve  200  to angle away from axis  255 . Apertures  600  in insulators  215 ,  220  may accommodate compression screws  245  that hold upper insulator  215  and lower insulator  220  together after assembly with pivoting retaining sleeve  200 .  FIG. 11  illustrates the manner in which ball  205  may seat within socket  210  of upper insulator  215  and lower insulator  220 , with lower insulator sliding around retaining sleeves  200  to complete socket  210 . Compression screws  245  may be employed to compress upper insulator and lower insulator  200  encasing retaining sleeves  200 , together. 
     Returning to  FIGS. 3A and 3B , socket  210  around ball  205  of pivoting retaining sleeve  200  may be a gap and/or a circular or rounded space formed by one of upper insulator  215 , lower insulator  220  or both. In some embodiments, socket  210  may be contiguous with a conduit through insulating blocks that accommodates tubular portion  400  of retaining sleeve  200  and/or phase  500 . Socket  210  may accommodate ball  205  and provide ball  205  freedom to rotate around pivot point  235  through and around cone  800 . Ball  205  and socket  210  joint may provide an angle θ around axis  255 , such as up to 30-40° from axis  255 , allowing pivoting retaining sleeve  200  to rotate, roll, pivot and/or otherwise move out of the way, with motion around central axis  255  and/or pivot point  235 , to allow an installer to tie-in other power cable phases  500 . Ball  205  in socket  210  may permit motion around three axes such as pitch, yaw and roll, with a common center (pivot point  235 ). The angle and/or size of tolerance  240 , clearance  310 , lower insulating block  220 , seal skirt  230  and/or the ratio between the outer diameters of ball  205  and tubular portion  400 , may determine the range of motion of ball  205  and socket  210  joint.  FIG. 3B  shows pivoting retaining sleeve  200  rotated out of the way by engaging ball  205  and socket  210  joint. Each phase  500  may be moved inside pivoting retaining sleeve  200  in such manner which may reduce stress on lower insulator  220 , sleeve  200  and/or phase  500 . 
     Turning to  FIG. 12 , a “round” and/or in this instance where three phases  500  are employed, triangular configuration of phases  500  is shown in a round lower insulator  220 , with all three pivoting retaining sleeves  200  parallel to axis  255 . In the embodiment of  FIG. 12 , pothead  250  may be sealed to motor head  1700  (shown in  FIG. 17A ) with elastomeric ring  260  (shown in  FIG. 2A ) placed around skirt seal  230 .  FIG. 13  illustrates a bottom view of the triangular and/or round phase configuration of  FIG. 12  with retaining sleeves  200  pivoted outward from axis  255  in a configuration that may give maximum access to all three phases  500  at once. Because of pivoting retaining sleeves  200 , reduced stress may be placed on phase  500  and/or lower insulator  220 , in this configuration, which may best accommodate the tie-in process. As shown in  FIG. 13 , phases in the triangular and/or round configuration may pivot until skirt seal  230  obstructs further pivot of retaining sleeve  200  and/or until offset is no longer desired. 
       FIG. 14  illustrates an orthogonal view of pothead assembly  250  with all three retaining sleeves  200  pivoted inward in one embodiment of the invention. This configuration of pivoting retaining sleeves  200  may allow gathering all three phases  500  together for additional insulation wrapping, as well as making the connection compact and therefore easier to push into motor head  1700  during installation.  FIGS. 15A-15B  illustrate additional views of pothead housing  225  of an illustrative embodiment for an elliptical insulator  215 ,  220  and/or a linear (side-by-side) arrangement of phases  500 . 
     Turning to  FIGS. 16A and 16B , a power cable phase  500  compatible with one or more embodiments of the invention may be an insulated electrical cable that includes conductor  505  surrounded by cable insulation  515 . In some embodiments, the cable may contain multi-wire conductors  505  each wrapped in its own insulation  515  and then bound together as phase  500 . Each motor lead extension (MLE)  1975  (shown in  FIG. 19 ) may include three phases  500  for a three-phase, squirrel cage induction motor  1935 . Conductor  505  may be copper or aluminum, for example. Cable insulation layer  515  may for example be Ethylene Propylene Diene Monomer (EPDM), rubber, polypropylene, polyethylene, or similar high temperature polymeric elastomer. In a three phase motor, such as ESP induction motor  1935 , three phases  500  may be included in pothead assembly  250  of illustrative embodiments. Insulation layer  515  of power cable  1940  may be surrounded by an extruded lead sheath and/or armor (not shown) to protect cable insulation as it extends the length of ESP assembly  1900  downhole. A lead sheath and/or armor may terminate prior to extension and/or passing of phase  500  through retaining sleeve  200 . Conducting pins  510  may extend from electrical conductor  505  and transfer current to motor  1935  through corresponding electrical receptacles in motor head  1700 . Pivoting retaining sleeves  200  of illustrative embodiments may enclose each phase  500  as it extends out the bottom of pothead  250 , and may allow an installer to beneficially maneuver each phase  500  during phase  500  tie-in.  FIGS. 16A and 16B  illustrate a cross-section of pothead assembly  250  showing pivoting retaining sleeve  200  with phase  500  and terminal pin  510  of an illustrative embodiment, with  FIG. 16A  in a pivoted orientation and  FIG. 16B  with phases  500  in a parallel orientation. 
     A method of installing the three-phase power cable  1940  into the ESP motor head  1700  includes the steps of splicing a three-phase power cable  1940  and/or MLE  1975  to expose three separate phases  500  of power cable  1940 . Next, the installer may place the terminating end of each phase  500 , one at a time, into the central conduit and/or top of socket  210  opening of upper insulator  215  within pothead housing  225 ; passing each phase  500 , one at a time, through ball joint  205  at one end of pivoting retaining sleeve  200  and continuing on through tubular portion  400  of pivoting retaining sleeve  200  thereby passing through lower insulator  220 . To create enough space to connect the terminating end of a first phase  500  to a terminal connector of ESP motor head  1700 , the installer may bend the terminating ends of a second and third phase  500  away from the first phase  500  by pivoting the corresponding retaining sleeves  200 , for example up to 35° from central axis  255 . When the space is ready, the installer may connect the terminating end of the first phase  500  to a first terminal connector of ESP motor head  1700 . Next, the installer may tie the terminating end of the first phase  500  to the first terminal connector of ESP motor head  1700  by wrapping the connection in insulating material, such as, for example, Kapton® (a registered trademark of E. I. du Pont de Nemours and Company, a U.S. Delaware corporation) tape. This method is repeated by creating a space, connecting and tying the terminating ends for each of the second and third phases  500  and/or any additional phases  500  in turn until all phases  500  are tied to ESP motor head  1700 . Finally, the installer pushes pothead assembly  250  into motor head  1700  and seals pothead  250  to motor head  1700  connection with an O-ring or similar elastomeric retaining mechanism.  FIG. 17A  and  FIG. 17B  illustrate pothead  250  assembly having pothead housing  225  of an illustrative embodiment inserted into motor head  1700 .  FIG. 18  illustrates a plan view of a pothead assembly  250  with terminal pins  155  installed of an illustrative embodiment. When all phases  500  are installed with their conductor  505  and terminal pins  510 , pothead assembly  250  may appear as seen in  FIG. 18 . 
       FIG. 19  illustrates an ESP assembly having a pothead retaining sleeve of an illustrative embodiment. ESP assembly  1900  may be located downhole in a well below surface  1905  and may extend, for example, several hundred or a few thousand feet deep. ESP assembly  1900  may be vertical, horizontal or may be curved, bent and/or angled, depending on well direction. The well may be an oil well, water well, and/or well containing other hydrocarbons, such as natural gas, and/or another production fluid from underground formation  1910 . ESP assembly  1900  may be separated from underground formation  1910  by well casing  1915 . Production fluid may enter well casing  1915  through casing perforations (not shown). Casing perforations may be either above or below ESP intake  1950 . 
     ESP assembly  1900  may include, from bottom to top, downhole sensors  1930  which may detect and provide information such motor speed, internal motor temperature, pump discharge pressure, downhole flow rate and/or other operating conditions to a user interface, variable speed drive controller and/or data collection computer in cabinet  1920 . ESP motor  1935  may be an induction motor, such as a two-pole, three phase squirrel cage induction motor. Power cable  1940  may provide power to ESP motor  1935  and/or carry data from downhole sensors  1930  to surface  1905 . ESP cabinet  1920  at surface  1905  may contain a power source  1925  to which power cable  1940  connects. Downstream of motor  1935  may be motor protector  1945 , ESP intake  1950 , multi-stage centrifugal ESP pump  1955  and production tubing  1995 . Motor protector  1945  may serve to equalize pressure and keep the motor oil separate from well fluid. ESP intake  1950  may include intake ports and/or a slotted screen and may serve as the intake to centrifugal ESP pump  1955 . ESP pump  1955  may be a multi-stage centrifugal pump including stacked impeller and diffuser stages. Other components of ESP assemblies may also be included in ESP assembly  1900 , such as a tandem charge pump (not shown) or gas separator (not shown) located between centrifugal ESP pump  1955  and intake  1950  and/or a gas separator may serve as the pump intake. Shafts of motor  1935 , motor protector  1945 , ESP intake  1950  and ESP pump  1955  may be connected together (i.e., splined) and be rotated by motor  1935 . Production tubing  1995  may carry lifted fluid from the discharge of ESP pump  1355  towards wellhead  1965 . 
     Power cable  1940  may extend from power source  1925  at surface  1905  to motor lead extension (MLE)  1975 . Cable connection  1985  may connect power cable  1940  to MLE  1975 . MLE  1975  may plug in, tape in, spline in or otherwise electrically connect power cable  1940  to motor  1935  to provide power to motor  1935 . Pothead assembly  250  may enclose the electrical connection between MLE  1975  and head  1700  of motor  1935 . Power cable  1940  may deliver power to motor  1935  through electric conductor  505  making up one or more motor phases  500 . 
     A pothead retaining sleeve apparatus, system and method has been described. Illustrative embodiments may provide pivoting of the retaining sleeves during installation providing space to tie-in the power cable phases, such as the connections in an ESP assembly. Illustrative embodiments may provide an improved ability to install the phases into the motor head without creating undue stress on the phase cables and/or insulating blocks. 
     Further modifications and alternative embodiments of various aspects of the invention may be apparent to those skilled in the art in view of this description. Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the general manner of carrying out the invention. It is to be understood that the forms of the invention shown and described herein are to be taken as the presently preferred embodiments. Elements and materials may be substituted for those illustrated and described herein, parts and processes may be reversed, and certain features of the invention may be utilized independently, all as would be apparent to one skilled in the art after having the benefit of this description of the invention. Changes may be made in the elements described herein without departing from the scope and range of equivalents as described in the following claims. In addition, it is to be understood that features described herein independently may, in certain embodiments, be combined.