Patent Publication Number: US-2016245410-A1

Title: Shaft seal assembly

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     Applicant Inpro/Seal LLC, a limited liability company organized under the laws of the state of Delaware and the United States of America, requests entry into the National Phase in the United States by and through this application which is based on PCT Patent Application, assigned serial number PCT/US2014/058325, filed on Sep. 30, 2014, which is incorporated by reference herein in its entirety. 
     FIELD OF THE INVENTION 
     The present invention relates to a shaft seal assembly with multiple embodiments. In certain embodiments, the shaft seal assembly may be used as a product seal between a product vessel and a shaft therein. 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     No federal funds were used to create or develop the invention herein. 
     REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISK APPENDIX 
     N/A 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order that the advantages of the invention will be readily understood, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered limited of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings. 
         FIG. 1  is a perspective exterior view of the shaft seal assembly. 
         FIG. 2  is an exterior end view of the shaft seal assembly with the shaft element aligned. 
         FIG. 3  is a sectional view of a first embodiment of the shaft seal assembly, as shown in  FIG. 2  and mounted to a housing. 
         FIG. 3A  illustrates the first surface seal-shaft integrity during angular and radial shaft alignment. 
         FIG. 3B  illustrates second surface seal-shaft integrity during angular and radial shaft alignment. 
         FIG. 4  is an exterior end view with the shaft misaligned. 
         FIG. 5  is a sectional view of the first embodiment as shown in  FIG. 3  with both angular and radial misalignment of the shaft applied. 
         FIG. 5A  illustrates first seal-shaft integrity allowed by articulation during angular and radial shaft misalignment. 
         FIG. 5B  illustrates second seal-shaft integrity allowed by articulation during angular and radial shaft misalignment. 
         FIG. 6  is a sectional view of a second embodiment of the shaft seal assembly as shown in  FIG. 2 . 
         FIG. 7  is a sectional view of a third embodiment as shown in  FIG. 2 . 
         FIG. 8  is a perspective view of a fourth embodiment as mounted to a vessel wall. 
         FIG. 9  is a cross-sectional view of a first embodiment of the pressure balanced shaft seal assembly mounted to a housing wherein the shaft is in alignment. 
         FIG. 9A  is a detailed view of the portion of the first embodiment of the pressure balanced shaft seal assembly adjacent the vent wherein the shaft is in alignment. 
         FIG. 9B  is a detailed view of the portion of first embodiment of the pressure balanced shaft seal assembly adjacent the fluid return pathway wherein the shaft is in alignment. 
         FIG. 10  is a cross-sectional view of the first embodiment of the pressure balanced shaft seal assembly shown during shaft misalignment. 
         FIG. 10A  is a detailed view of the portion of the first embodiment of the pressure balanced shaft seal assembly adjacent the vent wherein the shaft is misaligned. 
         FIG. 10B  is a detailed view of the portion of the first embodiment of the pressure balanced shaft seal assembly adjacent the fluid return pathway wherein the shaft is misaligned. 
         FIG. 11  is a cross-sectional view of a second embodiment of the pressure balanced shaft seal assembly wherein the shaft is in alignment. 
         FIG. 12  is a cross-sectional view of a third embodiment of the pressure balanced shaft seal assembly wherein the shaft is in alignment. 
         FIG. 13  is a cross-sectional view of another embodiment of a bearing isolator (or shaft seal assembly) configured with a rotor. 
         FIG. 14  is a cross-sectional view of a portion of yet another embodiment of a bearing isolator (or shaft seal assembly) configured with a rotor. 
         FIG. 14A  is a cross-sectional view of the portion of the embodiment of a bearing isolator shown in  FIG. 14  with the shaft misaligned and/or radially displaced. 
         FIG. 15  is a partial cross-sectional view of the embodiment of a bearing isolator shown in  FIG. 13  wherein the shaft is misaligned and/or radially displaced. 
         FIG. 15A  is a detailed view of a portion of the embodiment bearing isolator shown in  FIG. 15 . 
         FIG. 16A  is an exterior face view of an illustrative embodiment of a multi-hole shaft seal assembly, wherein certain hidden surfaces are shown with broken lines. 
         FIG. 16B  is a cross-sectional view of the embodiment of a multi-hole shaft seal assembly shown in  FIG. 16A  along line A-A. 
         FIG. 17A  is an exterior face view of one embodiment of a sealing member that may be used with various embodiments of a multi-hole shaft seal assembly. 
         FIG. 17B  is a cross-sectional view of the embodiment of a sealing member shown in  FIG. 17A  along line K-K. 
       
         
           
             
                 
              
                 
                     
                 
                 
                   DETAILED DESCRIPTION - ELEMENT LISTING (FIGS. 1-12) 
                 
              
             
             
                 
                 
                 
              
                 
                     
                   Description 
                   Element No. 
                 
                 
                     
                     
                 
                 
                     
                   Shaft 
                    1 
                 
                 
                     
                   Fixed stator 
                    2 
                 
                 
                     
                   Fixed stator (part-line) 
                    2a 
                 
                 
                     
                   Labyrinth seal 
                    3 
                 
                 
                     
                   Radiused face 
                    3a 
                 
                 
                     
                   Floating stator 
                    4 
                 
                 
                     
                   Fluid return pathway 
                    5 
                 
                 
                     
                   Shaft seal clearance 
                    6 
                 
                 
                     
                   First o-ring 
                    7 
                 
                 
                     
                   Anti-rotation pin 
                    8 
                 
                 
                     
                   Vent 
                    9 
                 
                 
                     
                   Anti-rotation groove (floating stator) 
                   10 
                 
                 
                     
                   Spherical interface 
                   11 
                 
                 
                     
                   Anti-rotation pin 
                   12 
                 
                 
                     
                   Second o-ring 
                   13 
                 
                 
                     
                   Labyrinth seal pattern grooves 
                   14 
                 
                 
                     
                   First o-ring channel 
                   15 
                 
                 
                     
                   Cavity for anti-rotation device (fixed stator) 
                   16 
                 
                 
                     
                   Axial face of labyrinth seal 
                   17 
                 
                 
                     
                   Axial face of floating stator 
                   18 
                 
                 
                     
                   Second o-ring channel 
                   19 
                 
                 
                     
                   First clearance between floating stator/fixed stator 
                   20 
                 
                 
                     
                   Second clearance between floating stator/fixed stator 
                   21 
                 
                 
                     
                   Throttle groove 
                   22 
                 
                 
                     
                   Labyrinth pattern annular groove 
                   23 
                 
                 
                     
                   Sleeve 
                   24 
                 
                 
                     
                   Shaft seal assembly 
                   25 
                 
                 
                     
                   Throttle (alignment skate) 
                   26 
                 
                 
                     
                   Floating stator annular groove 
                   27 
                 
                 
                     
                   Labyrinth seal passage 
                   28 
                 
                 
                     
                   Floating stator passage 
                   29 
                 
                 
                     
                   Housing 
                   30 
                 
                 
                     
                   Angle of misalignment 
                   31 
                 
                 
                     
                   Bearings and bearing cavity 
                   32 
                 
                 
                     
                   Mounting bolts 
                   33 
                 
                 
                     
                   Vessel wall 
                   34 
                 
                 
                     
                   Pressure balanced shaft seal assembly 
                   40 
                 
                 
                     
                   Labyrinth seal interior face 
                   42 
                 
                 
                     
                   Floating stator interior face 
                   44 
                 
                 
                     
                   Pressure balancing annular channel 
                   46 
                 
                 
                     
                   First radial interface 
                   47a 
                 
                 
                     
                   Second radial interface 
                   47b 
                 
                 
                     
                   Fixed stator annular groove 
                   48 
                 
                 
                     
                   Annular groove radial-interior surface 
                   48a 
                 
                 
                     
                     
                 
              
             
           
         
       
     
    
    
     DETAILED DESCRIPTION 
     Before the various embodiments of the present invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that phraseology and terminology used herein with reference to device or element orientation (such as, for example, terms like “front”, “back”, “up”, “down”, “top”, “bottom”, and the like) are only used to simplify description of the present invention, and do not alone indicate or imply that the device or element referred to must have a particular orientation. In addition, terms such as “first”, “second”, and “third” are used herein and in the appended claims for purposes of description and are not intended to indicate or imply relative importance or significance. Furthermore, any dimensions recited or called out herein are for exemplary purposes only and are not meant to limit the scope of the present disclosure in any way unless so recited in the claims. 
       FIGS. 1-5  provide various views of a first illustrative embodiment of the shaft seal assembly  25  that allows for sealing various lubricating solutions within bearing housing  30  and/or preventing ingress of contaminants to the housing  30 , which may be configured as a bearing housing.  FIGS. 6 and 7  provide alternative illustrative embodiments of the shaft seal assembly  25  wherein sealing fluids are used. Applicant herein defines sealing fluids to include at least both liquids and vapors. Applicant considers air, nitrogen, water and steam as well as any other fluid that may work with the proposed shaft seal assembly to provide a pressurized fluid barrier for any and all embodiments disclosed herein to be within the purview of the present disclosure. The gas or fluid chosen may be based at least upon process suitability with the product to be sealed. 
       FIG. 1  is a perspective exterior view of the first illustrative embodiment of a shaft seal assembly  25  arranged and engaged with a shaft  1  inserted through the fixed stator  2  of shaft seal assembly  25 .  FIG. 2  is an exterior end view of the shaft seal assembly with shaft  1  aligned within the shaft seal assembly  25 . 
       FIG. 3  is a sectional view of a first embodiment of the shaft seal assembly  25  shown in  FIG. 2  illustrating that the shaft seal assembly  25  may be configured as a labyrinth seal for retaining lubrication solution within the bearing cavity  32  of housing  30  and/or preventing ingress of contaminants into the housing  30 . The shaft  1  shown in  FIG. 3  may experience radial, angular or axial movement relative to the fixed stator  2  or a portion thereof at various times. The fixed stator  2  of the shaft seal assembly  25  may be engaged with a housing  30  via any suitable method and/or structure, including but not limited to flange-mounted or press-fit. The shaft seal assembly  25  may also be used in applications with a rotating housing and stationary shaft. (Not shown) As required by the particular application of the shaft  1  and/or shaft seal assembly  25 , the shaft  1  may be allowed to move freely in the axial direction in relation to the shaft seal assembly  25 . 
     A labyrinth seal  3  having an interior surface may be positioned adjacent shaft  1 . A defined clearance  6  may exist between the interior surface of said labyrinth seal  3  and the shaft  1 . A radiused surface  3   a  may be configured such that it is opposite the interior surface of the labyrinth seal  3 . The radiused surface  3   a  of the labyrinth seal  3  and the interior of the floating stator  4  may be configured to form a spherical interface  11 . O-ring channels  15  and o-rings  7  may be disposed to cooperate with the radiused surface  3   a  of the labyrinth seal  3  to seal (or trap) fluid migration through, between and along engaged labyrinth seal  3  and floating stator  4  while maintaining a spherical interface  11 , which spherical interface  11  may allow limited relative rotational movement (articulation) between labyrinth seal  3  and floating stator  4 . 
     o-ring channels  15 , as shown, may be machined into the floating stator  4  and may be positioned at the spherical interface  11  with labyrinth seal  3 . O-ring channels  15  may be configured such that they are annular and continuous in relation to labyrinth seal  3 . The o-ring channel  15  and o-ring  7  may also be placed in the labyrinth seal  3  adjacent the spherical interface  11 . In certain embodiments, o-rings  7  may be constructed of materials that are compatible with both the product to be sealed and the preferred sealing fluid. O-ring channels  15  and o-rings  7  are but one possible combination of structures that may be used to seal various potions within the shaft seal assembly  25 . Any other structures and/or method suitable for the particular embodiment of a shaft seal assembly  25  may be used without limitation. 
     Strategically placed anti-rotation pin(s)  12  may be inserted into anti-rotation grooves  10  and may serve to limit relative rotational movement between labyrinth seal  3  and floating stator  4 . A plurality of anti-rotation grooves  10  and pins  12  may be placed around the radius of the shaft  1 . If the shaft seal assembly  25  is used in combination with a sealing fluid, strategic anti-rotation pins  12  may be removed allowing corresponding anti-rotation grooves  10  to serve as a fluid passage through vent  9  and lubricant return  5 , one illustrative embodiment of which is shown in  FIG. 7 . Additionally, the relationship of the diameters of anti-rotation pins  12  and anti-rotation grooves  10  may be selected to allow more or less angular misalignment of the shaft  1 , respectively. For example, a relatively small-diameter anti-rotation pin  12  used with a large-diameter anti-rotation groove  10  would allow for greater relative movement of the labyrinth seal  3  in relation to the floating stator  4  in response to angular misalignment of shaft  1 . A labyrinth seal  3  is one possible embodiment of a sealing structure that may be used adjacent to the shaft  1  within the shaft seal assembly  25 . However, other structures and/or methods may be used to achieve similar functionality without limitation. 
     An annular channel may be formed within fixed stator  2  and may be defined by clearance  20  and  21  as allowed between the exterior of said floating stator  4  and the interior of the fixed stator  2  of shaft seal assembly  25 . The annular channel of fixed stator  2  is highlighted as A-A′ in  FIG. 2 . The annular channel of the fixed stator  2  may be formed with interior surfaces that are configured such that they are substantially perpendicular to said shaft  1 . The exterior surfaces of the floating stator  4 , which may be substantially encompassed within the annular channel of the fixed stator  2 , may cooperatively engage with the first and second interior perpendicular faces of the fixed stator  2 . An inner interface may be formed by the first (shaft seal assembly  25  inboard side) perpendicular annular channel surface of the fixed stator  2  engaging with the first (inboard side) perpendicular face of the floating stator  4 . An outer interface may be formed by the second (shaft seal assembly  25  outboard side) perpendicular annular interior channel surface of the fixed stator  2  engaging with the second (outboard side) perpendicular face of the floating stator  4 . O-ring channels  19  and o-rings  13  may be disposed therein and may cooperate with the surfaces of floating stator  4  that are in perpendicular to relation to shaft  1 . These o-rings  13  may function to seal (or trap) fluid migration between and along engaged floating stator  4  while allowing limited relative rotational movement between floating stator  4  and fixed stator  2 . Floating stator  4  and fixed stator  2  are one possible embodiment of cooperatively engaged portions of a shaft seal assembly  25  that may be configured to allow relative motion between the portions in at least one dimension, and which may be used in combination with labyrinth seal  3  within the shaft seal assembly  25 . However, other structures and/or methods may be used to achieve similar functionality without limitation. 
     o-ring channels  19  may be configured such that they are annular and continuous in relation to shaft  1 . In an embodiment not shown herein, the o-ring channels  19  and o-rings  13  may be placed in the body of the floating stator  4  rather than the fixed stator  2 . It is contemplated that for many applications it may be optimal to place those o-ring channels  19  and corresponding o-rings  13  in similar proximal relation. In certain embodiments, o-rings  7  may be constructed of materials that are compatible with both the product to be sealed and the preferred sealing fluid. o-ring channels  15  and o-rings  7  are but one possible combination of structures that may be used to seal various potions within the shaft seal assembly  25 . Any other structures and/or method suitable for the particular embodiment of a shaft seal assembly  25  may be used without limitation. 
     Strategically placed anti-rotation pin(s)  8  may be inserted into anti-rotation groove(s)  16  and may serve to limit both relative radial and rotational movement between floating stator  4  and interior side of fixed stator  2 . A plurality of anti-rotation grooves  16  and pins  8  may be placed around the radius of the shaft  1 . The relationship of the diameters of anti-rotation pins  8  and anti-rotation grooves  16  may also be selected to allow more or less angular misalignment of the shaft. For example, a small-diameter anti-rotation pin  8  and large-diameter fixed stator anti-rotation groove may allow for greater relative movement of the labyrinth seal  3  in response to angular misalignment of shaft  1 . 
     The labyrinth pattern seal grooves  14  may be pressure equalized by venting through one or more vents  9 . If so desired, the vents  9  may be supplied with a pressurized sealing fluid such that the sealing fluid over-pressurizes the labyrinth area  14  and shaft seal clearance  6  to increase the efficacy of shaft seal assembly  25 . A spherical interface  11  between the labyrinth seal  3  and the floating stator  4  may be configured to allow for angular misalignment between the shaft  1  and fixed stator  2 . O-ring channels  19  are annular with the shaft  1  and, as shown, may be machined into the fixed stator  2  and positioned at the interface between the fixed stator  2  and floating stator  4 . O-ring channel  19  may also be placed in the floating stator  4  and may be engaged with o-rings  13 , which may be configured to provide sealing contact with the fixed stator  2 . 
       FIG. 3A  illustrates seal-shaft integrity during angular and radial shaft  1  alignment. This view highlights the alignment of the axial face  17  of the labyrinth seal  3  and the axial face  18  of the floating stator  4 . Particular focus is drawn to the alignment of the axial faces  17 ,  18  at the spherical interface  11  between the floating stator  4  and labyrinth  3 .  FIG. 3B  illustrates the shaft-seal integrity during angular and radial shaft  1  alignment at the surface opposite that shown in  FIG. 3A . This view highlights the alignment of the axial faces  17 ,  18  of labyrinth seal  3  and floating stator  4 , respectively, for the opposite portion of the shaft seal assembly  25  as shown in  FIG. 3A . Those of ordinary skill in the art will appreciate that because the shaft  1  and the illustrative embodiments of a shaft seal assembly  25  are of a circular shape and nature, the surfaces are shown  360  degrees around shaft  1 . Again, particular focus is drawn to the alignment of the axial faces  17 ,  18  at the spherical interface  11  between the labyrinth seal  3  and floating stator  4 .  FIGS. 3A and 3B  also illustrate the first defined clearance  20  between the floating stator  4  and the fixed stator  2  and the second defined clearance  21  between the floating stator  4  and fixed stator  2  and opposite the first defined clearance  20 . 
     In  FIGS. 2, 3, 3A and 3B , the shaft  1  is not experiencing radial, angular or axial movement with respect to a housing  30 . Accordingly, in the illustrative embodiments the width of the defined clearances  20  and  21 , which may be substantially equal, may indicate little movement or misalignment upon the floating stator  4 . 
       FIG. 4  is an exterior end view of the shaft seal assembly  25  with the rotatable shaft  1  misaligned therein.  FIG. 5  is a sectional view of the first embodiment of the shaft seal assembly  25  as shown in  FIG. 3  with both angular and radial misalignment of the shaft  1  applied. The shaft  1  as shown in  FIG. 5  is also of the type that may experience radial, angular or axial movement relative to the fixed stator  2  (and/or housing  30 ) of the shaft seal assembly  25 . 
     As shown at  FIG. 5 , the defined radial clearance  6  of labyrinth seal  3  with shaft  1  may be maintained even though the angle of shaft misalignment  31  has changed. The shaft  1  still may be allowed to move freely in the axial direction even though the angle of shaft misalignment  31  has changed. The arrangement of the shaft seal assembly  25  may allow the labyrinth seal  3  to move with the floating stator  4  upon introduction of radial movement of said shaft  1 . 
     The labyrinth seal  3  and floating stator  4  may be secured together by one or more compressed o-rings  7  or any other suitable structure and/or method. Rotation of the labyrinth seal  3  within the floating stator  4  may be prevented by anti-rotation members, which may include but are not limited to screws, anti-rotation pins  8 , or similar devices to inhibit rotation. The pins as shown in  FIGS. 3, 3A, 3B, 5, 6 and 7  are one structure for preventing rotation of the labyrinth seal  3  and floating stator  4 . However, any other suitable structure and/or method may be used to achieve similar results without limitation. 
     Lubricant, sealing fluid, or other media may be collected and drained through a series of one or more optional drains or lubricant return pathways  5 . The labyrinth seal  3  may be pressure-equalized by venting through one or more vents  9 . If so desired, the vents  9  may be supplied with pressurized air or other gas or fluid media to over-pressurize the labyrinth seal  3  to increase seal efficacy. The combination of close tolerances between the cooperatively engaged mechanical portions of the shaft seal assembly  25  and pressurized sealing fluid may inhibit both product and contaminant contact with the internals of the shaft seal assembly  25 . The spherical interface  11  between the labyrinth seal  3  and the floating stator  4  may be configured to allow for angular misalignment between the shaft  1  and fixed stator  2 . O-ring channel  19  and o-ring  13 , which may be disposed therein, may cooperate with the opposing faces of the floating stator  4 , which may be configured such that they are substantially in perpendicular relation to the rotational axis of the shaft  1 . In this manner, the o-rings  13  may cooperate with the floating stator  4  to seal (or trap) fluid migration between and along the floating stator  4  while allowing relative radial movement between stator  4  and fixed stator  2 . 
       FIG. 5A  illustrates seal-shaft integrity allowed by the shaft seal assembly  25  during angular and radial shaft  1  misalignment. This view highlights the offset or articulation of the axial faces  17  of the labyrinth seal  3  may have in relation the axial faces  18  of the floating stator  4  for a first portion of the shaft seal assembly  25 . Particular focus is drawn to the offset of the axial faces  17 ,  18  at the spherical interface  11  between labyrinth seal  3  and floating stator  4 . 
       FIG. 5B  illustrates seal-shaft integrity for a second surface, opposite the first surface shown in  FIG. 5A , during angular and radial shaft misalignment. This view highlights that during misalignment of shaft  1 , axial faces  17 ,  18 , of the labyrinth seal  3  and floating stator  4 , respectively, may not be aligned but instead move (articulate) in relation to each other. The shaft-to-seal clearance  6  may be maintained in response to the shaft  1  misalignment and the overall seal integrity may not be compromised because the seal integrity of the floating stator  4  to fixed stator  2  and the floating stator  4  to labyrinth seal  3  may be maintained during shaft  1  misalignment. Those of ordinary skill in the art will appreciate that because the shaft  1  and shaft seal assembly  25  may be circular in shape and nature, the surfaces are shown  360  degrees around shaft  1 .  FIGS. 5A and 5B  also illustrate the first clearance or gap  20  between the floating stator  4  and the fixed stator  2  and the second clearance or gap  21  between the floating stator  4  and fixed stator  2  and opposite the first clearance or gap  20  during relative movement (other than rotational) between the shaft  1  and the housing  30 . 
     In  FIGS. 4, 5, 5A and 5B , the shaft  1  is experiencing radial, angular, or axial movement during rotation of the shaft  1  and the width of the gaps or clearances  20 ,  21  are shown as having changed in response to that movement as compared to the gaps or clearances  20 ,  21  depicted in  FIGS. 3, 3A and 3B . The change in dimensions of clearance  20 ,  21  indicate the floating stator  4  may move in response to the movement or angular misalignment of shaft  1 . The shaft seal assembly  25  may allow articulation between axial faces  17 ,  18 , maintenance of spherical interface  11  and radial movement at first and second clearance,  20 ,  21 , respectively, while maintaining shaft seal clearance  6 . 
       FIG. 6  is a sectional view of a second embodiment of the shaft seal assembly  25  as shown in  FIG. 2  for over-pressurization with alternative labyrinth seal pattern grooves  14 . In this embodiment, the labyrinth seal pattern grooves  14  may be comprised of a friction-reducing substance such as polytetrafluoroethylene (PTFE), wherein the friction-reducing substance may be configured such that it forms a close clearance to the shaft  1 . PTFE is also sometimes referred to as Teflon®, which is manufactured and marketed by Dupont. PTFE is a plastic with high chemical resistance, low and high temperature capability, resistance to weathering, low friction, electrical and thermal insulation, and high lubricity. Carbon or any other materials without limitation may be substituted for PTFE to provide the necessary sealing qualities and lubricous qualities for labyrinth seal pattern grooves  14 . 
     Pressurized sealing fluids may be supplied to over-pressurize the lubricious labyrinth pattern  26  as shown in  FIG. 6 . The pressurized sealing fluids may be introduced to the annular groove  23  of the throttle  26  through one or more inlets. Throttle  26  may also be referred to as “an alignment skate” by those of ordinary skill in the art. Throttle  26  may allow the labyrinth seal  3  to respond to movement of the shaft  1  caused by the misalignment of the shaft  1 . The pressurized sealing fluid may pass through the close clearance formed between the shaft  1  and labyrinth seal  3  having throttle  26 . The close proximity of the throttle  26  to the shaft  1  also may create resistance to the sealing fluid flow over the shaft  1  and may cause pressure to build up inside the annular groove  23 . Floating annular groove  27  in cooperation and connection with annular groove  23  also may provide an outlet for excess sealing fluid to be bled out of shaft seal assembly  25  for pressure equalization or to maintain a continuous fluid purge on the shaft sealing assembly  25  during operation. An advantage afforded by this aspect of the shaft sealing assembly  25  is its application wherein “clean-in place” product-seal decontamination procedures are preferred or required. Examples would include food grade applications. 
       FIG. 7  illustrates shaft seal assembly  25  with the anti-rotation pin  12  removed to improve visualization of the inlets. These would typically be comprised of, but are not limited to, a series of ports, inlets or passages about the circumference of the shaft seal assembly  25 .  FIG. 7  also illustrates that the shape and pattern of the labyrinth seal  3  may be varied from one embodiment of the shaft seal assembly  25  to the next. The shape of throttles  26  may also be varied as shown by the square profile shown at throttle groove  22  in addition to the circular-type  26 . Also note that where direct contact with the shaft  1  is not desired, the shaft seal assembly  25  may be used in combination with a separate sleeve  24  that would be attached by varied means to the shaft  1 . 
       FIG. 8  shows that another embodiment of the shaft seal assembly  25  wherein the shaft seal assembly  25  has been affixed to a vessel wall  34 . The shaft seal assembly  25  may be affixed to vessel wall  34  through securement members (e.g., including but not limited to mounting bolts  33 ) to ensure improved sealing wherein shaft  1  is subjected to angular misalignment. The mounting bolts  33  and slots (not numbered) through the shaft seal assembly  25  exterior are one structure and method of mounting the shaft seal assembly  25  to a housing  30 . However, any suitable structure and/or method may be used without limitation. 
     In certain applications, especially those wherein the process side of shaft seal assembly  25  (generally the area to the left of the shaft seal assembly  25  as shown in  FIGS. 3-3B and 5-7 ) is at an increased pressure, it is desirable for the shaft seal assembly  25  to be configured to balance the pressure experienced by the shaft seal assembly  25  in the axial direction. A pressure balanced shaft seal assembly  40  that balances the pressure (in the axial direction) that the product applies to the labyrinth seal interior face  42  and floating stator interior face  44  is shown in  FIGS. 9-12 . 
     In the first embodiment of the pressure balanced shaft seal assembly as shown in  FIGS. 9-10B , the shaft sealing member (i.e., the labyrinth seal  3  in combination with the floating stator  4 ) includes a pressure balancing annular channel  46 . Save for the pressure balancing annular channel  46 , the pressure balanced shaft seal assembly  40  may operate in generally the same manner as the shaft seal assembly  25  shown in  FIGS. 1-8  and described in detail above. That is, the floating stator  4  may be positioned in the fixed stator annular groove  48 . The first clearance between floating stator/fixed stator  20 , which in the embodiments pictured herein may be between the floating stator radial-exterior surface  45  and the annular groove radial-interior surface  48   a  (shown in  FIGS. 9A and 9B ), may account at least for radial perturbations of the shaft  1  with respect to the housing  30 . The spherical interface  11  between the floating stator  4  and the labyrinth seal  3  may account at least for angular perturbations of the shaft  1  with respect to the housing  30 . 
     The pressure balancing annular channel  46  may be formed in the floating stator  4  adjacent the first radial interface  47   a  between the floating stator  4  and the fixed stator  2 , as shown in  FIGS. 9-10  for the first embodiment. As shown in the various embodiments pictured herein, the first radial interface  47   a  between the floating stator  4  and the fixed stator  2  may be adjacent the portion of the fixed stator  2  fashioned with the cavity for anti-rotation device  16 . That is, the axial face of the floating stator  4  that is positioned within the fixed stator  2  and furthest from the process side of the pressure balanced shaft seal assembly  40 . A second radial interface  47   b  between the floating stator  4  and fixed stator  2 , which may be substantially parallel to the first radial interface  47   a,  may be positioned closer to the process side of the pressure balanced shaft seal assembly  40  as compared to the first radial interface  47   a.    
     In many applications the optimal radial dimension of the pressure balancing annular channel  46  may be substantially similar to the radial dimension of the floating stator interior face  44  so that the area of the floating stator  4  acted upon by the product and the area of the floating stator  4  acted upon by the sealing fluid may have relatively equal surface areas. In such a configuration, the axial forces may generally balance if the product and the sealing fluid are pressurized to approximately the same value. Accordingly, the optimal radial dimension of the pressure balancing annular channel  46  may depend on the design characteristics of the entire system, and the radial dimension of the pressure balancing annular channel  46  may be any suitable amount for a particular application, whether greater or less than the radial dimension of the floating stator interior face  44 . The axial dimension of the pressure balancing annular channel  46  may also vary depending on the design characteristics of the entire system, including but not limited to the specific sealing fluid that is used, the product pressure, and the pressure of the sealing fluid. In some applications the optimal axial dimension of the pressure balancing annular channel  46  will be  0 . 005  of an inch, but may be greater in other embodiments and less in still other embodiments. 
     The pressure balancing annular channel  46  may allow sealing fluid introduced into the first clearance between floating stator/fixed stator  20  (from where the sealing fluid may enter the pressure balancing annular channel  46 ) to act upon the floating stator  4  in an axial direction. Typically, the process side of the pressure balanced shaft seal assembly  40  (generally the area to the left of the pressure balanced shaft seal assembly  40  as shown in  FIGS. 9-12 ) experiences forces from the process fluid acting upon the labyrinth seal interior face  42  and floating stator interior face  44 . These forces are most often due to the pressure generated by the rotating equipment to which the shaft  1  is coupled. For example, if the shaft  1  is coupled to a fluid pump generating seventy pounds per square inch (psi) of head pressure, the process side of the pressure balanced shaft seal assembly  40  may be pressurized to approximately  70  psi. This pressurized fluid may act upon the labyrinth seal interior face  42  and floating stator interior face  44 , and consequently urge the labyrinth seal  3  and floating stator  4  in the axial direction away from the process side of the pressure balancing shaft seal assembly  40  (i.e., generally to the right side of the drawing as depicted in  FIGS. 9-12 ). By contrast, sealing fluid located in the pressure balancing annular channel  46  may urge the labyrinth seal  3  and floating stator  4  in the axial direction toward the process side of the pressure balancing shaft seal assembly  40 , which may substantially cancel the axial force the product exerts upon the pressure balancing shaft seal assembly  40 , depending on the design of the sealing fluid system. 
       FIGS. 11 and 12  show a second and third embodiment of the pressure balanced shaft seal assembly  40 , respectively. The second and third embodiments of the pressure balanced shaft seal assembly  40  generally correspond to the second and third embodiments of the shaft seal assembly  25  as shown in  FIGS. 7 and 8  and described in detail above. However, as with the first embodiment of the pressure balanced shaft seal assembly  40  as shown in  FIGS. 9-10B , the second and third embodiments include a pressure balancing annular channel  46 . 
     The various embodiments of the pressure balanced shaft seal assembly  40  pictured and described herein may be formed with a fixed stator  2  and floating stator  4  that may be comprised of two distinct portions. These embodiments may facilitate assembly of the pressure balanced shaft seal assembly  40  since in the embodiments pictured herein the majority of the floating stator  4  may be positioned within the fixed stator  2 . When installing a pressure balanced shaft seal assembly  40  according to the first embodiment (as pictured in  FIGS. 9-10B ), the first portion of fixed stator  2  (i.e., the portion adjacent the process side of the pressure balanced shaft seal assembly  40 ) may be affixed to a housing  30 . Next, the floating stator  4  and labyrinth seal  3  may be positioned as a singular assembled piece (wherein the components forming the spherical interface  11  have been preassembled) between the shaft  1  and the first portion of the fixed stator  2 . The placement of the floating stator  4  and labyrinth seal  3  within the fixed stator  3  may forms the second axial interface  47   b  between the fixed stator  2  and floating stator  4 . Finally, the second portion of the fixed stator  2  (i.e., the portion furthest from the process side of the pressure balanced shaft seal assembly  40 ) may be positioned adjacent to and affixed to the first portion of the fixed stator  2 . The positioning of the second portion of the fixed stator  2  subsequently may form the first radial interface  47   a  between the fixed stator  2  and floating stator  4 . 
     Alternatively, the floating stator  4  and labyrinth seal  3  may be separately positioned within the fixed stator annular groove  48 . For example, after the first portion of the fixed stator  2  has been affixed to the housing  30 , the first portion of the floating stator  4  may be positioned within the fixed stator annular groove  48 . The placement of the first portion of the floating stator  4  within the fixed stator annular groove  48  may form the second axial interface  47   b  between the fixed stator  2  and floating stator  4 . Next, the labyrinth seal  3  may be positioned adjacent the shaft  3 , the placement of which may form a portion of the spherical interface  11  between the floating stator  4  and labyrinth seal  3 . Next, the second portion of the floating stator  4  may be positioned adjacent the first portion of the floating stator  4  and affixed thereto with a plurality of anti- rotation pins  8 , which may complete the spherical interface  11  between the floating stator  4  and labyrinth seal  3 . Finally, the second portion of the fixed stator  2  may be affixed to the first portion of the fixed stator  2  with a plurality of bolts, rivets, or other fasteners without limitation, the placement of which may form the first axial interface  47   a  between the floating stator  4  and fixed stator  2 . Any suitable securing members known to those skilled in the art may be used to affix the first and second portions of the floating stator  4  to one another or to affix the first and second portions of the fixed stator  2  to one another in any embodiments of a shaft seal assembly  25  or pressure balanced shaft seal assembly  40  without limitation. 
     
       
         
           
               
            
               
                   
               
               
                 ELEMENT LISTING (FIGS. 13-15A) 
               
            
           
           
               
               
               
            
               
                   
                 Description 
                 Element No. 
               
               
                   
                   
               
               
                   
                 Shaft 
                  10 
               
               
                   
                 Bearing isolator 
                  18 
               
               
                   
                 Housing 
                  19 
               
               
                   
                 Rotor 
                  20 
               
               
                   
                 Stator 
                  30, 31a 
               
               
                   
                 Fixed stator 
                  31 
               
               
                   
                 Passage 
                  40, 40a 
               
               
                   
                 Spherical surface 
                  50, 51 
               
               
                   
                 Clearance 
                  52 
               
               
                   
                 Frictional seal 
                  60 
               
               
                   
                 Flange unit 
                  61a 
               
               
                   
                 Center point 
                  80 
               
               
                   
                 Conduit 
                  99 
               
               
                   
                 Fluid 
                 100 
               
               
                   
                 Pin 
                 101 
               
               
                   
                 Annular recess 
                 102 
               
               
                   
                   
               
            
           
         
       
     
       FIG. 13  shows another embodiment of a bearing isolator  18  (or shaft seal assembly) mounted adjacent a shaft  10 . The shaft  10  may extend through the bearing isolator  18  and/or the housing  19 . A source of gas or fluid,  100  which may include but is not limited water, gas, vapor and/or lubricant, may also be in communication with the bearing isolator  18  via conduit  99 . The rotor  20  may be affixed to the shaft  10  by means by a frictional seal  60 , which may be configured as one or more o-rings. The rotor  20  may be configured to follow the rotational movement of the shaft  10  because of the frictional engagement of the seals  60 . The passages  40  and  40   a  may be configured as shown but will not be described in detail here because such description is already understood by those of ordinary skill in the art. 
     A pair of corresponding spherical surfaces  50  and  51  may be used to create a self-aligning radial clearance  52  between the rotor  20  and the stator  30  prior to, during, and after use. This clearance  52  may be maintained at a constant value even as the shaft  10  becomes misaligned during use. Various amounts and direction of misalignment between the centerline of the shaft  10  and the housing  19  are illustrated in  FIGS. 15-17 . An annular recess  102  between the stator  30  and fixed stator  31  may allow the bearing isolator  18  to accommodate a predetermined amount of radial shaft displacement. 
     In the embodiments shown herein, the spherical surfaces  50 ,  51  may have a center point identical from the axial faces of both the rotor and stator  20 ,  30 , respectively. However, the spherical surfaces  50 ,  51  may be radially, and/or as shown, vertically spaced apart. These spherical surfaces  50 ,  51  may move radially in response to and/or in connection with and/or in concert with the radially positioning of other components of the bearing isolator  18 . Typically, if the shaft  10  becomes misaligned with respect to the housing  19 , the rotor  20  may consequently become misaligned with respect thereto, and then the spherical surfaces  50 ,  51  and/or the stator  30 , moving radially within the annular recess of the fixed stator  31 , may compensate for the misalignment. 
       FIGS. 15 and 15A  illustrate that in one embodiment of the bearing isolator  18 , the rotor  20  may move with respect to the stator  30 ,  31  as shaft  10  is misaligned with respect to housing  19  through the interaction between spherical surfaces  50 ,  51 . Such relative movement to help to ensure the distances between the center points of the rotor  20  and stator  30  and a fixed point on the housing  19  are constant or relatively constant during use. 
     In the embodiment of the bearing isolator  18  shown in  FIGS. 14 and 14A , the spherical surfaces  50 ,  51  may be positioned on a fixed stator  31  and stator  31   a,  respectively, rather than on the rotor  20  and stator  30 . Still referring to  FIGS. 14 and 14A , this design may allow the rotor  20  and stator  31   a  to move with respect to the fixed stator  31 , flange unit  61   a,  and/or housing  19 . The rotor  20 , stator  31   a,  and fixed stator  31  may move radially with respect to the flange unit  61   a  (and consequently with respect to the housing  19 ) as best shown in  FIG. 14A . In this embodiment of the bearing isolator  18  there may be a very minimal amount of relative rotation between the spherical surfaces  50 ,  51 . 
     The embodiment of the bearing isolator  18  shown in  FIGS. 14 and 14A  may provide for controlled radial movement of the fixed stator  31 , stator  31   a,  and/or rotor  20  with respect to flange unit  61   a,  which flange unit  61   a  may be engaged with a housing  19 . Rotational movement of the fixed stator  30  with respect to the flange unit  61   a  may be prevented by anti-rotational pins  101 . The fixed stator  31  may be frictionally secured to the flange unit  61   a  using a frictional seal  61 , which may be made of any material with sufficient elasticity and frictional characteristics to hold the fixed stator  31  in a fixed radial position with respect to the flange unit  61   a  but still be responsive to the radial forces when the shaft  10  is misaligned. Changes to the radial position of the fixed stator  31 , stator  31   a,  and/or rotor  20  and the resulting positions thereof (as well as the resulting position of the interface between the fixed stator  31  and stator  31   a ) may occur until the radial force is fully accommodated or until the maximum radial displacement of the bearing isolator  18  is reached. 
     Referring now to  FIGS. 15 and 15A , in operation the rotor  20  may be moved radially as the shaft  10  becomes misaligned with respect to the housing  19 . Radial movement of the spherical surfaces  50 ,  51  between the stator  31   a  and fixed stator  31  may result from this pressure.  FIG. 15  shows potential resultant radial movement of center point  80  as the shaft  10  is misaligned. During normal operation, the shaft  10  is typically horizontal with respect to the orientation shown in  FIG. 15 , as represented by line A. As the shaft  10  becomes misaligned in a manner represented by line B, the center point  80  may move to a point along line A″. As the shaft  10  becomes misaligned in a manner represented by line B′, the center point  80  may move to a point along line A′. However, in other shaft  10  misalignments, the radial positions of the rotor  20 , stator  30 , and/or fixed stator  31  may be constant and the spherical surfaces  50 ,  51  may compensate for the shaft  10  misalignment. From the preceding description it will be apparent that the bearing isolator  18  may provide a constant seal around the shaft  10  because the distance between the spherical surfaces  50 ,  51  may be maintained as a constant regardless of shaft  10  misalignment of a normal or design nature. 
     The physical dimensions of the spherical surfaces  50  and  51  may vary in linear value and in distance from the center point  80 , depending on the specific application of the bearing isolator  18 . These variations will be utilized to accommodate different sizes of shafts and seals and different amounts of misalignment, and therefore in no way limit the scope of the bearing isolator  18  as disclosed herein. Additionally, and suitable structure and/or method for engaging various elements with one another either rotationally, fixedly, or with various degrees of freedom of motion therebetween may be used with the shaft seal assembly  18  without limitation, including but not limited to screws, bolts, pins, chemical adhesives, interference fits, and/or combinations thereof. 
     
       
         
           
               
            
               
                   
               
               
                 ELEMENT LISTING (FIGS. 16-17) 
               
            
           
           
               
               
               
            
               
                   
                 Description 
                 Element No. 
               
               
                   
                   
               
               
                   
                 Shaft seal assembly 
                 10 
               
               
                   
                 Shaft 
                 12 
               
               
                   
                 Fastener 
                 14 
               
               
                   
                 Fixed stator 
                 20 
               
               
                   
                 Fixed stator seal groove 
                 20a 
               
               
                   
                 Main body 
                 21 
               
               
                   
                 Face plate 
                 22 
               
               
                   
                 Face plate pin recess 
                 22a 
               
               
                   
                 Face plate seal groove 
                 22b 
               
               
                   
                 Inlet 
                 24 
               
               
                   
                 Annular recess 
                 26 
               
               
                   
                 Seal 
                 28 
               
               
                   
                 Floating stator 
                 30 
               
               
                   
                 Floating stator seal groove 
                 30a 
               
               
                   
                 Radial exterior surface 
                 32 
               
               
                   
                 First pin recess 
                 33 
               
               
                   
                 Pin 
                 34 
               
               
                   
                 Second pin recess 
                 35 
               
               
                   
                 Second pin recess enlarged portion 
                 35a 
               
               
                   
                 Floating stator annular groove 
                 37 
               
               
                   
                 Concave surface 
                 38 
               
               
                   
                 Sealing member 
                 40 
               
               
                   
                 Recess 
                 42 
               
               
                   
                 Radial bore 
                 44 
               
               
                   
                 Radial bore inlet 
                 44a 
               
               
                   
                 Radial bore outlet 
                 44b 
               
               
                   
                 Radial interior surface 
                 46 
               
               
                   
                 Convex surface 
                 48 
               
               
                   
                   
               
            
           
         
       
     
     Another embodiment of a shaft seal assembly  10  is shown in  FIGS. 16A &amp; 16B . This embodiment is similar to the embodiment of the shaft seal assembly  25  described above and shown in  FIGS. 1-12 . The shaft seal assembly  10  may include a fixed stator  20 , floating stator  30 , and a sealing member  40 , as shown. In the pictured embodiment, the sealing member  40  may be positioned adjacent a shaft  12  that is rotatable with respect to the shaft seal assembly  10  and/or housing. Accordingly, a rotational interface may exist between a radial interior surface  46  of the sealing member  40  positioned adjacent the shaft  12  and an exterior portion of the shaft  12 . In other embodiments of the shaft seal assembly  10  not pictured herein, the sealing member  40  may be engaged with the shaft  12  such that it rotates therewith (e.g., the shaft seal assembly  10  may be configured with a rotor). In such an embodiment, a rotational interface may exist between a concave surface  38  of the floating stator  30  and a convex surface  48  of the sealing member  40 . Accordingly, the scope of the shaft seal assembly  10  as disclosed herein extends to shaft seal assemblies  10  in which the sealing member  40  does or does not rotate with a shaft  12 . 
     The embodiment of the shaft seal assembly  10  shown in  FIGS. 16A &amp; 16B  may include a fixed stator  20  that may be securely mounted to a housing (not shown in  FIGS. 16A &amp; 16B ) by any suitable methods and/or structure. The fixed stator  20  may include a main body  21  and a face plate  22  that may be engaged with one another via one or more fasteners  14 . It is contemplated that a fixed stator  20  formed with a main body  21  and face plate  22  may facilitate ease of installation of the shaft seal assembly  10  in certain applications. In such applications, the main body  21  may be affixed to the housing, the sealing member  40  and floating stator  30  may be positioned appropriately, and then the face plate  22  may be secured to the main body  21 . However, the scope of the present disclosure is in no way limited by the specific mounting and/or installation method of the shaft seal assembly  10 . 
     The fixed stator  20  may be formed with an annular recess  26  into which a portion of the floating stator  30  and/or sealing member  40  may be positioned. A predetermined clearance between the radial exterior surface  32  of the floating stator  30  (as well as the axial exterior surfaces thereof) and the interior surfaces of the annular recess  26  may be selected to allow for a predetermined amount of relative radial and/or axial movement between the fixed stator  20  and floating stator  30 . At least one pin  34  (which may be radially oriented as in the embodiment shown in  FIGS. 16A &amp; 16B ) may be engaged with the floating stator  30  at a second pin recess  35 , and a portion of the pin  34  may extend into a recess  42  formed in the sealing member  40 . Additionally, other pins (not shown, but which may be axially oriented) also may be engaged with the floating stator about a first pin recess  33 , and a portion of that pin may extend into a face plate pin recess  22   a.  In the illustrative embodiment shown in  FIGS. 16A &amp; 16B , the pins  35  may mitigate relative rotation between the floating stator  30  and the sealing member  40 . Axially oriented pins (not shown) may mitigate relative rotation between the floating stator  30  and the fixed stator  20 . The axial interfaces between the floating stator  30  and fixed stator  20  may be sealed with seals  28 , which seals  28  may be positioned in fixed stator seal grooves  20   a  and/or face plate seal grooves  22   b.  The seals  28  may be configured as o-rings, but may be differently configured in other embodiments of the shaft seal assembly  10  without limitation. 
     The floating stator  30  may also be formed with a concave surface  38  in a radial interior portion thereof. This concave surface  38  may form a semi-spherical interface with a corresponding convex surface  48  formed in the radial exterior portion of the sealing member  40 . Accordingly, the shaft seal assembly  10  shown in  FIGS. 16A &amp; 16B  may accommodate shaft  12  misalignment, shaft  12  radial movement, and shaft  12  axial movement with respect to the shaft seal assembly  10  and/or equipment housing in an identical and/or similar manner to that previously described for the shaft seal assemblies  25  shown in  FIGS. 1-12 . 
     The illustrative embodiment of the shaft seal assembly  10  also may include various fluid conduits for applying a sealing fluid to the shaft seal assembly  10 . The fixed stator  20  may be formed with one or more inlets  24  for introduction of a sealing fluid to the shaft seal assembly  10 . The inlet  24  may be in fluid communication with the annular recess  26  formed in the fixed stator  20 , which annular recess  26  may be in fluid communication with one or more radial passages (not shown) formed in the floating stator  30  and extending from the radial exterior surface  32  thereof to the concave surface  38  thereof. Alternatively, or in addition to the one or more radial passages, the second pin recess  35  formed in the floating stator  30  may be configured to allow a specific amount of sealing fluid to traverse the length of the second pin recess  35  in a radially inward direction. The radially interior terminus of the second pin recess  35  may be formed with a second pin recess enlarged portion  35   a.  Alternatively, the floating stator  30  may be formed with a floating stator annular groove  37  on the concave surface  38  thereof. These radial passages, second pin recess  35 , second pin recess enlarged portion  35   a,  and/or floating stator annular groove  37  may serve as a conduit for sealing fluid from the annular recess  26  of the fixed stator  20  to the convex surface  48  of the sealing member  40 . Accordingly, the scope of the shaft seal assembly  10  is not limited by the specific combinations of fluid conduits disclosed herein, but extends to all configurations of fluid conduits that may supply a sealing fluid to the sealing member  40 . 
     The fixed stator  20  and/or seals  28  between the fixed stator  20  and floating stator  30  may be configured so that the majority of sealing fluid introduced to the inlet  24  passes through the floating stator  30  (by any fluid conduit configuration, as explained above) in a radially inward direction. The semi-spherical interface between the floating stator  30  concave surface  38  and the sealing member  40  convex surface  48  may be sealed with seals  28 , which seals  28  may be positioned in floating stator seal grooves  30   a  and/or sealing member seal grooves (not shown). The seals  28  may be configured as o-rings, but any suitable structure and/or method may be used without limitation. The floating stator  30 , sealing member  40 , and/or seals  28  therebetween may be configured so that the majority of sealing fluid exiting the floating stator  30  passes through the sealing member  40  through a plurality of radial bores  44  in a direction from the convex surface  48  of the sealing member  40  to the radial interior surface  46  thereof (i.e., in a generally radially inward direction, such that the sealing fluid exits the shaft seal assembly  10  adjacent the shaft  12 ). 
     The fixed stator  20 , floating stator  30 , and/or sealing member  40  may be configured such that the fluid conduits formed therein allow the majority of sealing fluid to exit the shaft seal assembly  10  from an area between the sealing member  40  and shaft  12  at a predetermined rate for a given set of operation parameters (e.g., sealing fluid viscosity, pressure, and/or volumetric flow rate, rpm of shaft  12 , etc.). The illustrative embodiment of the shaft seal assembly  10  may be formed with thirty two (32) radial bores  44  in the sealing member  40  in corresponding pairs equally spaced about the circumference of the sealing member, which is best shown in  FIGS. 17A &amp; 17B . Each radial bore  44  may be formed with a radial bore inlet  44   a  adjacent the convex surface  48  and a radial bore outlet  44   b  adjacent the radial interior surface  46 . However, in other embodiments of the sealing member  40  not shown herein, the sealing member  40  may be configured with differently configured radial bores  44 , different numbers of radial bores  44 , and/or different relative positions of radial bores  44  without limitation. 
     It is contemplated that the configuration of radial bores  44  shown in the embodiment of a sealing member  40  pictured in  FIGS. 17A and 17B  may be more efficient than other configurations in that a lower volumetric flow rate of sealing fluid may be required for a given set of operational parameters when compared to the prior art. Additionally, the smooth, generally cylindrical configuration of the radial interior surface  46  may create a pressurized fluid barrier between the shaft  12  and the sealing member  40  at the interface thereof (e.g., a “lift-off” seal). This may lead to a nearly frictionless shaft seal assembly  10  with no and/or minimal contact between the shaft  12  and the sealing member  40  during operation. However, in other embodiments, different numbers, spacing, and/or configurations of the fluid conduits in the fixed stator  20 , floating stator  30 , and/or sealing member  40  may be used without departing from the spirit and scope of the shaft seal assembly  10  as disclosed and claimed herein. 
     In light of the present disclosure, it will be apparent to those skilled in the art that the configuration of fluid conduits disclosed herein may be adapted to create a pressurized fluid barrier between any interface at which two elements are rotating with respect to one another, such as the articulated seal disclosed in U.S. Pat. No. 7,090,403. U.S. Pat. No. 7,090,403 is incorporated by reference herein in its entirety, and discloses embodiments of a shaft seal assembly having a spherical rotational interface between a rotor and a floating stator (such as those shown in  FIGS. 13, 15, and 15A ) and embodiments of a shaft seal assembly having a generally non-rotating spherical interface between two portions of a stator (such as those shown in  FIGS. 14 and 14A ). Accordingly, the scope of the shaft seal assembly  10  as disclosed herein is not limited by the location and/or type of rotational interface the shaft seal assembly  10  is configured to accommodate. 
     For example, in an embodiment not pictured herein, the stator  30  of an embodiment similar to that shown in  FIGS. 13, 15, and 15A  may be configured with one or more generally narrow diameter radial bores (which may be generally similar to those shown in the embodiment in  FIGS. 17A and 17B ). Those radial bores may be configured so as to provide fluid from an external source (which may be in fluid communication with passage  40 ) to the interface between spherical surfaces on the stator portions  31 ,  31   a  (which may be configured as a concave surface on stator  31  and a convex surface on stator  31   a ). Alternatively, the stator  31  may be configured with radial bores that serve to provide fluid from an external source (which may be in fluid communication with passage  40 ) to the interface between stator  31   a  and rotor  20 , which may be a rotational interface having a labyrinth seal pattern and/or one or more seals (which may be configured as o-rings) therein. 
     The specific configuration and/or physical dimensions of the various features of the fixed stator  20 , floating stator  30 , and/or sealing member  40  (e.g., the radial dimension of the annular recess  26 , the surface area of the concave surface  38  and/or convex surface  48 , the diameter, length, and orientation of the radial bores  44 , etc.) may vary depending on the specific application of the shaft seal assembly  10 . These variations may be utilized to accommodate different sizes of shafts  12  and/or shaft seal assemblies  10  and different amounts and/or types of relative movement between a shaft  12  and shaft seal assembly  10 . 
     The materials used to construct the shaft seal assemblies  10 ,  25  and various elements thereof will vary depending on the specific application, but it is contemplated that bronze, brass, stainless steel, or other non-sparking metals and/or metallic alloys and/or combinations thereof will be especially useful for some applications. Accordingly, the above-referenced elements may be constructed of any material known to those skilled in the art or later developed, which material is appropriate for the specific application of the shaft seal assembly  10 ,  25 , without departing from the spirit and scope of the shaft seal assemblies  10 ,  25  as disclosed and claimed herein. 
     Having described the preferred embodiments, other features of the shaft seal assemblies  10 ,  25  will undoubtedly occur to those of ordinary skill in the art, as will numerous modifications and alterations in the embodiments as illustrated herein, all of which may be achieved without departing from the spirit and scope of the shaft seal assemblies  10 ,  25  disclosed herein. Accordingly, the methods and embodiments pictured and described herein are for illustrative purposes only. 
     It should be noted that the shaft seal assemblies  10 ,  25  are not limited to the specific embodiments pictured and described herein, but are intended to apply to all similar apparatuses and methods for accommodating shaft(s) misalignment with respect to a housing and/or shaft seal assembly  10 ,  25 , whether the misalignment is angular, radial, and/or axial; and for configuring a shaft seal assembly  10  to create a pressurized fluid barrier between a rotating element and a non-rotating element. Modifications and alterations from the described embodiments will occur to those skilled in the art without departure from the spirit and scope of the shaft seal assemblies  10 ,  25 .