Abstract:
Method and system of a flange seal ring. At least some of the illustrative embodiments are systems comprising a metallic ring and a plurality of cogs. The metallic ring comprises a central bore that defines an internal diameter, a first sealing face that defines a first plane, a second sealing face that defines a second plane, a first groove in the first sealing face, and a second groove in the second sealing face. The plurality of cogs couple to the metallic ring, each cog extends through the first plane, and the plurality of cogs positioned one each at a plurality of radial positions around the metallic ring. At least one of the plurality of cogs configured to have an adjustable position relative to the central bore, and the cogs configured to align the central bore to a corresponding bore of a flange.

Description:
BACKGROUND 
       [0001]    In situations where pipes need to be connected together in a semi-permanent fashion, each pipe end is fitted with a flange, and the flanges are bolted together. There are several types of flanges, defined in part by the type of sealing surface provided on each flange face. For example, a raised face flange has a sealing surface that is raised in relation to the portion of the flange through which bolts extend, and the raised face is either smooth or has shallow circular grooves. When mating raised face flanges, a gasket material is positioned between the raised faces and held in place by compressive forces supplied by the bolts. A ring-type joint (RTJ) flange is yet another example of a type of flange. RTJ flanges have a circular ring groove on the flange face. A metallic ring, or ring gasket, is placed between two RTJ flanges in the ring groove, and the ring gasket is deformed or “coined” between the flanges to provide a seal. The compressive forces to deform the ring supplied by the bolts. 
         [0002]    In addition to different types of flanges, there are also different ratings for flanges, even of the same type. For example, a raised face flange for 30 inch pipe may come in a variety of ANSI ratings directly related to the internal pressure expected in the pipe. Size of the sealing surface for raised face flanges may vary slightly from flange-to-flange for a given flange size, in spite of each flange having a central passage of the same internal diameter. Likewise, the depth, width and/or location of a ring groove for RTJ flanges may change for different pressure ratings or may vary slightly from flange-to-flange in spite of each flange having a central passage of the same internal diameter. 
         [0003]    Ultrasonic flow meters are used to measure fluid flow (e.g., natural gas, oil, water) in a pipe. In some situations, ultrasonic meters are used to measure fluid flow for custody exchange purposes, and thus particular accuracy is needed. In order to verify the accuracy of an ultrasonic meter, new meters (and possibly rebuilt meters) require a flow calibration at a testing laboratory. However, selection of a flange type and pressure rating for a meter is customer dependent. Situations thus occur where a testing laboratory has a set of piping having an internal diameter matching that of an ultrasonic meter (e.g., 30 inches), as required by testing standards, but the testing laboratory may have flanges with different seal types and/or different pressure ratings. For example, the testing laboratory may use RTJ flanges having first pressure rating, and the meter to be tested may use raised face flanges having different pressure ratings than the RTJ flanges. Testing laboratories have addressed the issue in the past by having a plurality of pipe “spools” with each spool having different flange type on the meter end. However, construction and storing such spools is expensive, in some cases costing more than the meter to be tested. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0004]    For a detailed description of exemplary embodiments, reference will now be made to the accompanying drawings in which: 
           [0005]      FIG. 1  illustrates a raised face flange; 
           [0006]      FIG. 2  illustrates a ring-type joint flange; 
           [0007]      FIG. 3  illustrates a flange seal ring in accordance with at least some embodiments; 
           [0008]      FIG. 4  illustrates a perspective view of a block assembly in accordance with at least some embodiments; 
           [0009]      FIG. 5  illustrates a cross-sectional, elevation view of the block assembly of  FIG. 5  taken along line  5 - 5  of  FIG. 4 ; 
           [0010]      FIG. 6  illustrates a cross-sectional, elevation view of the block assembly interacting with a raised face flange; 
           [0011]      FIG. 7  illustrates a cross-sectional, elevation view of the block assembly interacting with a raised face flange having a raised face offset smaller than illustrated by  FIG. 6 ; and 
           [0012]      FIG. 8  illustrates a method in accordance with at least some embodiments. 
       
    
    
     NOTATION AND NOMENCLATURE 
       [0013]    Certain terms are used throughout the following description and claims to refer to particular system components. As one skilled in the art will appreciate, flow meter designers and manufacturers may refer to a component by different names. This document does not intend to distinguish between components that differ in name but not function. 
         [0014]    In the following discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to . . . .” Also, the term “couple” or “couples” is intended to mean either an indirect or direct connection. Thus, if a first device couples to a second device, that connection may be through a direct connection, or through an indirect connection via other devices and connections. 
       DETAILED DESCRIPTION 
       [0015]    The following discussion is directed to various embodiments of the invention. Although one or more of these embodiments may be preferred, the embodiments disclosed should not be interpreted, or otherwise used, as limiting the scope of the disclosure. In addition, one skilled in the art will understand that the following description has broad application, and the discussion of any embodiment is meant only to be exemplary of that embodiment, and not intended to intimate that the scope of the disclosure is limited to that embodiment. 
         [0016]    The various embodiments are directed to a flange seal ring that enables coupling of flanges of varying types (e.g., raised face, ring-type joint (RTJ)) and in some cases varying pressure ratings, without the need for adapters or pipe “spools”. For example, the flange seal ring of the various embodiments enables coupling a meter (e.g., ultrasonic meter) having a 150 ANSI raised face flange to piping of a testing laboratory having a 900 ANSI RTJ flange. Before turning to illustrative physical embodiments of the flange seal ring, the specification digresses briefly to a discussion of two specific types of flanges. 
         [0017]      FIG. 1  illustrates a raised face flange  10  usable with the flange seal ring of the various embodiments (not shown in  FIG. 2 ). In particular,  FIG. 1  illustrates both a cross-sectional view  12  and an elevation view  14  of a raised face flange  10 . The sealing feature of a raised face flange is the raised face  16 . The raised face  16  is defined by an inside diameter  18  of the central bore or central passage  20 , and an outside diameter  22  of the raised face  16 . As the name implies, the raised face is offset from the bolt face  24  by a distance “D”, which distance varies depending on the pressure rating of the flange. For example, in some pressure ratings the offset D is 0.06 inches (1.524 millimeters (mm)), and yet for other, higher pressure ratings the offset D is 0.25 inches (6.35 mm). When coupling two raised face flanges, a gasket material occupies the space between the two sealing surfaces, and the seal is achieved by compressive force supply by bolts in bolt holes  26 . 
         [0018]      FIG. 2  illustrates a RTJ flange  30  usable with the flange seal ring of the various embodiments (not shown in  FIG. 2 ). In particular,  FIG. 2  illustrates both a cross-sectional view  32  and an elevation view  34  of the RTJ flange  30 . The sealing feature of a RTJ flange is ring groove  36 . The ring groove  36  lies between the central passage  38  and the bolt holes  40 . On some RTJ flanges, the surface  42  within which the ring groove  36  is cut is also offset from the bolt face  44  by a distance “D”, but such an offset is not necessarily present. The width, depth and/or diameter of the ring groove  36  may vary for different pressure ratings, with larger ring grooves  36  (and correspondingly larger metallic ring gaskets) for higher pressure ratings. When coupling two RTJ flanges, the metallic ring gasket is placed between the flanges, and the metallic ring gasket resides at least partially within the ring groove  36  of each flange. The seal is achieved by deforming the metallic ring gasket by way of the compressive force supply by bolts in bolt holes  40 . The specification now turns to the illustrative embodiments of a flange seal ring. 
         [0019]      FIG. 3  illustrates an elevation view of a flange seal ring  50  in accordance with at least some embodiments. In particular,  FIG. 3  illustrates the flange seal ring  50  comprises a metallic ring  52 , and a plurality of block assemblies  54  (labeled  54 A,  54 B, and  54 C in  FIG. 3 ). In some embodiments, the metallic ring  52  is made of carbon steel. In other embodiments, such as low pressure applications, other metals may be equivalently used (e.g., aluminum). The metallic ring  52  defines a central bore  56  having an internal diameter  58 . The flange seal ring  50  further comprises a sealing face  60  that defines a plane (in the case of  FIG. 3 , the plane is parallel to the page). The central bore  56  is substantially perpendicular to the plane defined by the sealing face  60  (i.e., perpendicular within manufacturing tolerances). Though not visible in  FIG. 3 , the metallic ring  52  further comprises a second sealing face on the opposite side of the metallic ring  52 , which sealing face likewise defines a plane. In some embodiments, the plane defined by the first sealing face  60  and the second sealing face are substantially flat (i.e., flat within manufacturing tolerances) and substantially parallel (i.e., parallel within manufacturing tolerances). 
         [0020]    The metallic ring  52  further comprises an o-ring groove  62  that encircles the intersection of the central bore  56  and the sealing face  60 . Again, though not visible in  FIG. 3 , the second sealing face on the opposite side likewise has an o-ring groove. In embodiments configured for use with a 0.50 inch (12.7 mm) diameter elastomeric o-ring, each o-ring groove  62  is 0.375 inch (9.525 mm) in depth, 0.560 inch (14.224 mm) in width at the sealing face  60 , and has a 5 degree angle (the groove becoming more narrow with depth into the metallic ring  52 ). O-rings of different diameter may be equivalently used, and the width, depth and/or angle of the o-ring grooves may change accordingly. 
         [0021]    The flange seal ring  50  further comprises a plurality of block assemblies  54 . In the illustrative case of  FIG. 3 , three such block assemblies  54  are present at equally spaced radial locations on the outside diameter of the metallic ring  52 . Though three such block assemblies  54  are shown, greater or fewer block assemblies may be equivalently used. Each block assembly comprises a cog portion  64 . Though the relationship of the cog portions  64  to the metallic ring  52  are discussed more below, each of the cog portions extend through the plane defined by the sealing face  60  (i.e., out of the page). In accordance with some embodiments the cog portions  64  of the block assemblies  54  are made of carbon steel, but in other embodiments (e.g., smaller diameter metallic rings) the cog portions  64  may be made of other materials (e.g., aluminum, plastic). 
         [0022]      FIG. 4  illustrates a perspective view of a block assembly  54  in accordance with at least some embodiments. In particular,  FIG. 4  illustrates that block assemblies in accordance with at least some embodiments comprise a housing  70  made up of an upper housing  72  and lower housing  74 . The housing defines an interior volume  76  within which resides a lead screw  78 . The lead screw  78  comprises a shaft with external threads, and the cog  80  comprises an aperture with internal threads. As illustrated in  FIG. 4 , the cog  80  threadingly couples to the lead screw  78  by way of the aperture. By rotation of the lead screw  78 , as illustrated by arrow  82 , the location the cog  80  may be adjusted, as indicated by arrow  84 . Cog  80  comprises multiple cog portions, but in the perspective view of  FIG. 4  only cog portion  64  is visible. 
         [0023]      FIG. 5  is a cross-sectional, elevation view of the block assembly  54  taken substantially along lines  5 - 5  of  FIG. 4 . Moreover,  FIG. 5  illustrates portions of two flanges having differing sealing features in operational relationship to the block assembly  54  and metallic ring  52 . In particular,  FIG. 5  illustrates a portion of raised face flange  90  having a sealing feature in the form of a raised face  92 , and a portion of a RTJ flange  94  having a sealing feature in the form of a ring groove  96 . The inside diameter  98  of the central bore of the metallic ring  52  aligns with the inside diameters  100  and  102  of the raised face and RTJ flanges  90  and  94 , respectively. Two o-rings  104  and  106  reside one each within the o-ring grooves  108  and  110 , respectively. Because of compression force supplied by the bolts through the flanges, the o-rings  104  and  106  compress between the flanges and their respective o-ring grooves, forming a seal. 
         [0024]    Still referring to  FIG. 5 , the block assembly  54  housing  70  comprises the upper housing  72  and the lower housing  74 . Having a multiple-piece housing enables insertion of the lead screw  78  and cog  80  within the internal volume during assembly. After insertion of the various internal components, the lower housing  72  is coupled to the upper housing  72 , such as fasteners (e.g., bolts), welding or epoxy. Having the housing  70  separable near its base is merely illustrative. The housing  70  may be equivalently separable at any location that facilitates insertion of the lead screw  78  and cog  80 . Cog  80  comprises a large cog portion  112 , a small cog portion  114 , and an internally threaded aperture  116 . In the illustrative embodiments of  FIG. 5 , the large cog portion  112  is configured to extend through a plane defined by the sealing surface  60 A, and the large cog portion  112  interacts or mates with a portion of the sealing feature of the RTJ flange  94 . In particular, mitered portion  118  of the large cog portion  112  contacts and/or couples to the ring groove  96 . The size of the ring groove  96  may change as between RTJ flanges with differing pressure ratings (as illustrated by the dashed lines). In the event the flange seal ring  50  is used with a RTJ flange with larger ring groove  96  but same central passage internal diameter, the position of the cog  80  may be correspondingly changed by virtue of lead screw  78  to ensure contact of the large cog portion  112  to the ring groove  96  wall. In the configuration of  FIG. 5 , the small cog portion  114  extends opposite the large cog portion  112 , and resides between the planes defined by the sealing surfaces  60 A and  60 B. 
         [0025]      FIG. 6  is a cross-sectional, elevation view of the block assembly  54  similar to  FIG. 5 . Moreover,  FIG. 6  illustrates a portion of a raised face flange  120  in operational relationship to the large cog portion  112 . In particular, in addition to the mitered portion  118 , the large cog portion  112  defines a notch  122 . The notch  122  is configured to couple and/or mate to an outside diameter of a raised face  124  of raised face flange  120 . Thus, the illustrative large cog portion  112  may be used in operational relationship to a ring groove of a RTJ flange or the raised face of a raised face flange. In the illustrative case of  FIG. 6 , the offset  126  may be 0.25 inches (6.35 mm), and thus the large cog portion  112  is long enough to interact with the ring groove of a RTJ flange ( FIG. 5 ) and define the notch  122  yet short enough to be used with the illustrated raised face flange. However, the offset  126  of a raised face in relation to the bolt face  24  varies depending on the pressure rating of the flange. For lower pressure ratings, the offset  126  may be significantly less than 0.25 inches (6.35 mm), and in such circumstances the large cog portion  112 , if used, may hold the metallic ring  52  and/or o-ring  106  away from the sealing feature of the flange. 
         [0026]    In situations where the large cog portion  112  is too long, the portion of the cog  80  that extends through the plane of the sealing face  60 A may be changed by repositioning of the block assembly  54 . Returning briefly to  FIG. 4 , the block assembly  54  is held in place against the metallic ring  52  by way of a plurality of bolts  86  (labeled  86 A and  86 B in  FIG. 4 ). When the flange seal ring is to be used with a flange where the large cog portion  112  is too long, the block assembly  54  may be removed (by removal of bolts  86 ), turned 180 degrees, and then re-attached to the metallic ring  52 .  FIG. 7  illustrates a cross-sectional, elevation view of the block assembly  54  rotated in the metallic ring  52 . In particular, rotation of the block assembly  54  results in the small cog portion  114  extending through the plane defined by sealing face  60 A and large cog portion  112  being between the plane defined by the sealing surface  60 A and plane defined by the sealing face  60 B (the plane illustrated by dashed line  130 ). Small cog portion  114  defines a notch  132 . The depth of notch  132  of the small cog portion  114  is smaller than notch  122  of the large cog portion  112 . The notch  132  is configured to couple and/or mate to an outside diameter  134  of raised face  136 . The offset of the raised face  136  of  FIG. 7  is significantly smaller than that of  FIG. 6  (e.g., the offset may be 0.06 inches (1.524 mm), thus making use of the large cog portion  112  improper. 
         [0027]    Referring simultaneously to  FIGS. 6 and 7 . In  FIGS. 6 and 7 , only one flange is shown, the flange that interacts with the cog portion extending through the plane defined by sealing face  60 A. Though a second flange is not shown in either  FIG. 6  or  7 , it is noted that either type flange may be in operational relationship to the sealing face  60 B. 
         [0028]      FIG. 8  illustrates a method in accordance with at least some embodiments. In particular, the method starts (block  800 ) and proceeds to placing a flange seal ring against a sealing feature of a first flange (block  804 ). For example, the flange seal ring may be placed against a raised face of a raised face flange, or against the ring groove of a RTJ flange. Next, the seal ring is centered with respect to a central passage through the first flange by adjusting position of one or more cogs coupled to the seal ring (block  808 ). In some embodiments, centering the seal ring comprises adjusting a lead screw coupled to each cog. Finally, a second flange is coupled to the first flange with the seal ring between the flanges (block  812 ), and the method ends (block  816 ). The types of flanges that may be connected in accordance with the method may have central bores having substantially the same diameter, but further may have different pressure ratings and/or different sealing surface types. 
         [0029]    Using a flange seal ring of the various embodiments may eliminate, or at least reduce, the number of adapters or spools a testing laboratory may need to have on hand. Moreover, even in situations where flanges and pressure ratings as between a meter to be tested and the testing laboratory are the same, the expense of gaskets or metallic ring seals (e.g., $1000 for a large diameter gasket or large diameter metallic ring seal) may be eliminated by the reusable nature of the flange seal ring of the various embodiments. 
         [0030]    The above discussion is meant to be illustrative of the principles and various embodiments of the present invention. Numerous variations and modifications will become apparent to those skilled in the art once the above disclosure is fully appreciated. For example, in some embodiments the sealing faces of the metallic ring define their respectively planes by the entire sealing face lying in a plane; however, the sealing faces need not be planar, and other forms may be equivalently used (e.g., convex (bulging outwardly), or concave). It follows that a plane defined by a sealing face may be based any similar feature of the sealing face (e.g., peak of a convex sealing face, or valley of a concave sealing face). It is intended that the following claims be interpreted to embrace all such variations and modifications.