Abstract:
The present invention is directed toward a split retaining ring for a connection assembly adapted for connecting an instrument or other device to a vessel, such as a pressure vessel. The connection assembly includes a base, an instrument or device, and a split retaining ring wherein the split retaining ring includes overlapping end portions in order to substantially duplicate the strength and load resistance of a continuous retaining ring. The split retaining ring also includes an annular rib adapted for engaging a ferrule of the instrument or device in order to substantially sealing engage the instrument or device to the base. The retaining ring of the present invention can provide the required strength characteristics while be maintaining a thinner profile thereby making the split retaining ring compatible with a wider variety of instrumentation and devices.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This nonprovisional application claims the benefit of Provisional Patent Application Ser. No. 61/159,496 filed Mar. 12, 2009, the entire disclosure of which is incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    Pressure vessels are utilized in many industries for manufacturing products when maintaining specific temperatures and pressures is required. Industries using pressure vessels include but are not limited to pharmaceutical, chemical, food and beverage, medical, biotechnical, ethanol, dairy, water treatment, paper, cryogenic, and other industries requiring chemical or biological processing in a pressurized environment. The processes that require the use of pressure vessels often require instrumentation and other devices to measure and control operating conditions such as temperature, pressure, liquid level, and other parameters through various known instrumentation. Further, these industries may also require pressure vessels to have inlets, outlets, or ports to introduce or remove contents, obtain samples of the contents of the tank while maintaining a sterile or sealed environment, or perform other related actions. 
         [0003]    Connections utilizing a retaining ring to hold instrumentation and other devices in sealed connection with a base mounted to a pressure vessel are well known in the art. In many cases, the instrumentation and devices are configured such that a solid (i.e., continuous and non-split) retaining ring is not able to slide over the entire instrumentation or device. In such cases, it has become common to use a split retaining ring constructed of two or more sections. 
         [0004]    Split retaining ring connections, such as the NovAseptic® connector and the ASEPCONNECT™ connector, are well known in the art and utilize a base welded to the pressure vessel and a split retaining ring. The instrumentation is secured to the base by the split retaining ring that, when tightened, engages the instrument&#39;s ferrule and compresses the ferrule and an elastomeric seal against a seat in the base thereby effectuating the connection. The compression required to create the seal and connection is created using four or more threaded fasteners or bolts that can be tightened to achieve a desired compressive force and resistance. 
         [0005]    A large number of pressure vessels manufactured and in use today are outfitted with bases designed for utilizing split retaining ring connections. A shortcoming of the prior art bolted split retaining ring connection relates to the thickness of the split retaining ring itself. The two or more sections of the split retaining ring act independently of one another. Because the split retaining ring sections act independently from one another, the bending forces exerted on the sections&#39; free ends require the ring to be of an increased thickness, as compared to a solid ring, in order to meet certain industry codes, regulations and/or standards. The split retaining ring&#39;s increased thickness often presents clearance issues with the instrumentation and devices held in place by the split retaining ring. For example, the instrumentation and devices will sometimes have wires, fittings, couplings and other items extending therefrom that are obstructed by or in interference with the split retaining ring. 
         [0006]    Therefore, a need exists for an improved split retaining ring having a reduced thickness to decrease the total depth of the pressure vessel connection so as not to interfere with or obstruct the instrumentation or device the split retaining ring is holding in place. A need also exists for a split retaining ring that has the strength characteristics similar to those of a solid, continuous ring. A need further exists for a split retaining ring that has increased strength characteristics so that it can be manufactured from a smaller amount of material. 
       BRIEF SUMMARY OF THE INVENTION 
       [0007]    The present invention is generally directed towards a connection assembly having a base, an instrument, and a split retaining ring that includes at least two sections having overlapping ends in order to substantially duplicate the strength and load resistance of a continuous retaining ring. The split retaining ring of the present invention can provide the strength required by certain industry codes, regulations and standards while having a decreased thickness and being manufactured from a smaller amount of material. The decrease in the split retaining ring&#39;s thickness enables it to be compatible with a wider variety of existing instrumentation and devices currently available in the market place. 
         [0008]    One embodiment of the split retaining ring of the present invention includes ends that overlappingly engage one another to form an overlap joint. A threaded fastener may be located through the overlapped joint such that the split retaining ring of the present invention substantially duplicates the action of a solid, continuous retaining ring. In this embodiment, the instrumentation is secured to the base by tightening the threaded fastener in order to operably engage the instrumentation with the base until a desired torque or compression clamping force is reached. 
         [0009]    Another embodiment of the present invention is directed to a split retaining ring that may be used in connection with a base having a beveled flange disposed therearound. The split retaining ring in such an embodiment includes at least two sections having ends that are overlappingly engaged and a top surface that is beveled around at least a portion of its perimeter. The instrument or device is retained by the split retaining ring through a tri-clamp or other sanitary clamp known in the art constricting and clamping the ring&#39;s beveled top surface with the base&#39;s beveled flange. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
         [0010]    The accompanying drawing forms a part of the specification and is to be read in conjunction therewith, in which like reference numerals are employed to indicate like or similar parts in the various views, and wherein: 
           [0011]      FIG. 1  is a top perspective view of a prior art bolted split retaining ring connection assembly on a vessel; 
           [0012]      FIG. 1A  is a top perspective view of the assembled prior art bolted split retaining ring connection assembly having independent split retaining ring sections; 
           [0013]      FIG. 2  is an exploded view of the bolted split retaining ring connection assembly in accordance with one embodiment of the present invention; 
           [0014]      FIG. 3  is a top perspective view of an assembled bolted split retaining ring connection assembly in accordance with one embodiment of the present invention; 
           [0015]      FIG. 4  is a cross sectional view of the assembled bolted split retaining ring connection assembly in  FIG. 3  taken along the line  4 - 4 ; 
           [0016]      FIG. 5  is a top perspective exploded view of a clamped split retaining ring connection assembly in accordance with one embodiment of the present invention; and 
           [0017]      FIG. 6  is a cross sectional view of the assembled clamped split retaining ring connection assembly shown in  FIG. 5  in accordance with one embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0018]    The following detailed description of the invention references the accompanying drawing figures that illustrate specific embodiments in which the invention can be practiced. The embodiments are intended to describe aspects of the invention in sufficient detail to enable those skilled in the art to practice the invention. Other embodiments can be utilized and changes can be made without departing from the scope of the present invention. The present invention is defined by the appended claims and the description is, therefore, not to be taken in a limiting sense and shall not limit the scope of equivalents to which such claims are entitled. 
         [0019]    Turning now to the drawing figures,  FIG. 1  illustrates an embodiment of a split retaining ring connector known in the prior art to connect instrumentation to vessels, such as pressure vessels.  FIG. 1A  shows an embodiment of a prior art connector  100  including a base  102  that uses a recessed housing and a split retaining ring  104  to secure instrumentation  106  to the base  102 . The base  102  is typically coupled to the wall of the vessel  108  through a weld  110 . As illustrated, the retaining ring  104  is split into two independent sections  116  and  118 . These independent sections  116  and  118  of the prior art split retaining ring  104  must be thicker than a continuous ring in order resist the bending forces exerted on the sections&#39;  116  and  118  free ends and meet certain industry codes, regulations and/or standards. Each split retaining ring section  116  and  118  has two threaded rods  112  extending through two holes in the sections  116  and  118  and nuts  114  to tighten the sections  116  and  118  such that they engage a portion of a ferrule of an instrument or device  106  to be secured and apply the sufficient compressive clamping force to effectuate a seal and secure the connection. 
         [0020]      FIG. 2  illustrates an embodiment of the split retaining ring of the present invention with an exploded view of a pressure vessel connection assembly  10 . The pressure vessel connection assembly  10  of the present invention includes a base  12 , an instrument  14 , and a split retaining ring  16 . Base  12  of pressure vessel connection assembly  10  includes a top  18 , a bottom  20 , an outer face  22 , and an inner face  24 . As further illustrated in  FIG. 2 , base  12  has a circular geometry wherein base  12  has radius R 1  that generally defines outer face  22 . It would be appreciated by a person of skill in the art that base  12  is not limited to a circular shape. Base  12  may be any shape in the art including, but not limited to, a square, rectangle, oval, triangle, pentagon, hexagon, octagon and the like. 
         [0021]    As shown in  FIG. 2 , base  12  has radius R 2  that generally defines a base aperture  26 . Radius R 2  and aperture  26  generally correspond to a defined dimension corresponding to instrument  14  or other standard device dimensions known in the art. Aperture  26  is shown in  FIG. 2  having a circular geometry. However, aperture  26  may be configured to any geometrical shape known in the art including, but not limited to, a square, rectangle, oval, triangle, pentagon, hexagon, octagon and the like. Base  12  further includes a recessed instrument housing  28 . The area of instrument housing  28  of base  12  is generally defined by a radius R 3  from the connection centerline as shown in  FIG. 2 . Radius R 3  is generally greater than radius R 2  and less than radius R 1 . An embodiment of the present invention may also include threaded rods  30  that are received by and/or extend from base  12 . In another embodiment, the base  12  may include a threaded aperture for receiving a bolt (not shown) in place of rod  30 . As shown, the top  18  of base  32  includes at least one groove  32  allowing the connection assembly  10  to drain if condensation or other moisture is present within the instrument housing  28 . 
         [0022]    Device or instrument  14  can be any apparatus or instrument now known or hereafter developed for being connected to a pressure vessel including, but not limited to a sensor, temperature or pressure gauge, thermo-well, thermo-coupler, pressure switch, pump, reducer, fitting, valve, pipe, Ingold®-type adapter, sampling system, cleaning device and any other apparatus or instrumentation suitable for connection with a pressure vessel. It should be understood that for demonstration purposes, instrument  14  as shown in the figures merely represents an actual instrument that would be used in industry and that the actual instrument or device may be of a structure and form different from that depicted in the drawings. It should also be understood that while the vessel  108  may be described as being a pressure vessel, the present invention, including the retaining ring  104 , is suitable for use with non-pressure bearing vessels as well. 
         [0023]    Embodiments of certain instruments  14  generally include a ferrule  34  and a body portion  36  as shown in  FIG. 2 . Ferrule  34  has a diameter D 1  corresponding to a number of various standard sizes known in the art, with most sizes being in a range from about one to twelve (1-12) inches. It will be understood, however, that the present invention may be adapted for use with instruments  14  having ferrules  34  smaller than one (1) inch in diameter and larger than twelve (12) inches in diameter. Generally, instrument housing  28  of base  12  is configured to receive ferrule  34  of instrument  14 . Therefore, it will be appreciated by one skilled in the art that the present invention shall not be limited to a circular ferrule  34  and housing  28  as shown in  FIG. 2  and that ferrule  34  and housing  28  may each be any shape known in the art including, but not limited to, a square, rectangle, oval, triangle, pentagon, hexagon, octagon and the like. Embodiments of instrument  14  may also include body  36  having a diameter D 2 . 
         [0024]      FIG. 2  also illustrates an embodiment of split retaining ring  16  of the present invention. Split retaining ring  16  includes a first ring section  38  and a second ring section  40 . In one embodiment, first ring section  38  and second ring section  40  are identical to one another thereby increasing the manufacturing efficiency. In other words, two identically manufactured sections  38  and  40  may be brought together to form the ring  16 . In the embodiment illustrated in  FIG. 2 , both ring sections  38  and  40  include a top side  42 , a bottom side  44 , an inner face  46 , and an outer face  48 . Both ring sections  38  and  40  also include one overlap end  50  and one under-lap end  52 . The overlap end  50  of first ring section  38  will overlappingly engage under-lap end  52  of second ring section  40 . The overlap end  50  of second ring section  40  overlappingly engages under-lap end  52  of first ring section  38 . An embodiment of the present invention may alternatively include a first ring section  38  wherein both ends are configured as overlap ends  50  and second ring section  40  wherein both ends are configured as under-lap ends  52 . An embodiment of connection assembly  10  of the present invention may also include a split retaining ring  16  having more than two sections that overlappingly engage one another. 
         [0025]    An embodiment of split retaining ring  16  of the present invention includes an annular rib  54  proximate to inside face  46  of sections  38  and  40 . An embodiment of annular rib  54  of sections  38  and  40  may include at least one groove  56  as shown in  FIG. 2 . Groove  56  is generally configured transverse to said annular rib  54  such that groove  56  lines up with groove  32  on top  18  of base  12  when the split retaining ring  16  is in its assembled position. 
         [0026]    As shown, the first and second sections  38  and  40  split retaining ring  16  may have three apertures  58  at a defined spacing as seen in  FIG. 2 . The sections  38  and  40  may include an aperture  58  at each overlap end  50  and under-lap end  52 . When assembled, the ring sections  38  and  40  overlappingly engage to form a continuous ring and the apertures  58  of the overlap ends  50  and the under-lap ends  52  line up to result in a total of four apertures  58  in the assembled ring that match the pattern of the threaded rods  30  extending from base  12 . A person of skill in the art will appreciate that any total number of apertures  58  are within the scope of the present invention as the number of apertures  58  will vary upon the number and size of threaded rods  30  or bolts required for the connection to provide the required pressure force resistance. 
         [0027]      FIG. 3  illustrates an embodiment of the present invention wherein split retaining ring  16  has a radius R 4  that generally defines outer face  48 . While radius R 4  is shown as being approximately equal to radius R 1  of base  12 , it will be appreciated that radius R 4  may be greater than or less than the radius R 1  of the base  12 . As depicted in  FIG. 3 , the inner face  46  of split retaining ring sections  38  and  40  is defined by a radius R 5 . Radius R 5  is generally configured such that it defines an area larger than the cross-sectional area of body  36  of instrument  14  shown having diameter D 2 , yet smaller than the area defined by ferrule diameter D 1  (shown in  FIG. 2 ) thereby allowing instrument  14  to be retained in the base  12  of connection assembly  10  as seen in  FIG. 3 . Generally, split retaining ring  16  defines an interior opening of a shape and size that allows split retaining ring  16  to fit around the body  36  of instrument  14 , yet is smaller than the diameter D 1  of ferrule  34  of instrument  14  allowing instrument  14  to be retained by split retaining ring  16 . A person of skill in the art will appreciate that any embodiment of split retaining ring  16  that is consistent with this disclosure is within the scope of the present invention. 
         [0028]    Turning now to  FIG. 4 , a cross sectional view of connection assembly  10  is shown. Base  12  of connection assembly  10  is coupled to the wall of pressure vessel  108  by weld  62 . As illustrated, the inside face  24  of base  12  may be tapered. Base  12  generally includes a housing groove  64  in an instrument seat  66  in housing  28 . Housing groove  64  generally receives a projection  72  of a seal  68 . Seal  68  is typically formed from an elastomeric material; however, seal  68  can be any material known in the art that provides an air-tight and pressure resistant seal. Seal  68  also includes another projection  72  that is received by a ferrule groove  70  on the underside of beveled ferrule  34  of instrument  14  as instrument  14  bears on seal  68  and instrument seat  66  in housing  28 . Annular rib  54  of split retaining ring  16  engages on the beveled ferrule  34  of instrument  14 . Split retaining ring  16  generally includes annular rib  54  having an inside face  74  defined by radius R 5  and an outer face  76  defined by radius R 6 . Radius R 6  of annular rib  54  is generally configured such that annular rib  54  is received in housing  28  as shown in  FIG. 4 . An embodiment of inner face  74  of annular rib  54  may include a bevel (as shown) to match the beveled ferrule  34  of instrument  14 . 
         [0029]    In use, split retaining ring sections  38  and  40  overlappingly engage one another to form a substantially continuous ring, and split retaining ring  16  bears on instrument ferrule  34 . Nut  60  is operably engaged with threaded rod  30  wherein threaded rod  30  is received by and/or extends from the top  18  of base  12 . Nut  60  is tightened down to produce a compressive clamping force upon the split retaining ring  16  against the instrument  14  which in turn engages against seal  68  on instrument seat  66  in housing  28  of base  12 .  FIG. 4  illustrates threaded rod  30  passing through aperture  58  wherein overlap end  50  overlappingly engages under-lap end  52 . When nut  60  is tightened down to secure split retaining ring  16  against beveled ferrule  34  of instrument  14 , overlap end  50  and under-lap end  52  are compressed and clamped together. The frictional resistance of the faces of the end section is such that when nuts  60  are tightened to a specified torque, split retaining ring  16  becomes a substantially continuous ring. A person of skill in the art will appreciate that the present invention shall not be limited to a threaded rod and a nut and any fastener that provides adequate compression force and tensile strength, including but not limited to, bolts, screws, pins, cam-action fasteners, or other known fasteners in the art are within the scope of the present invention. 
         [0030]      FIGS. 5 and 6  demonstrate another embodiment of the present invention wherein a traditional tri-clamp  80  secures a split retaining ring  84  to base  86 . As shown in  FIG. 5 , base  86  includes a continuous beveled flange  78  around outside face  88  of base  86 . In one embodiment, split retaining ring  84  includes a first and a second split retaining ring section  90  and  92  and the two sections overlappingly engage one another as previously described above. The embodiment illustrated in  FIGS. 5 and 6  includes outside face  94  of both ring sections  90  and  92  having a beveled surface  82 . Circular clamp  80  fits around beveled flange  78  and bevel  82  of split retaining ring  84  and when clamp  80  is tightened, split retaining ring  84  is wedged downward towards base  86  sealing an instrument or device  14  in housing  96 . In general, base  86 , split retaining ring  84 , and clamp  80  are configured to accommodate the connection of any instrument or device known in the art. 
         [0031]    From the foregoing, it may be seen that the split retaining ring of the present invention is particularly well suited for the proposed usages thereof. Furthermore, since certain changes may be made in the above invention without departing from the scope hereof, it is intended that all matter contained in the above description or shown in the accompanying drawing be interpreted as illustrative and not in a limiting sense. It is also to be understood that the following claims are to cover certain generic and specific features described herein.