Abstract:
An annular sealing gasket for forming a sealing connection between a first tubular member and a second tubular member. The annular sealing gasket comprises a flexible sealing portion adapted to form a sealing connection between a first tubular member and a second tubular member and a body region adapted for supporting the flexible sealing portion and anchoring the annular sealing gasket to a secured connection. The body region further comprises spaced first and second conical legs extending convergingly away from the body region transversely from the flexible sealing portion.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The following application is a Non-provisional patent application claims priority from currently pending U.S. Provisional Application 61/559,284 filed Nov. 14, 2011 entitled SEALING GASKET and currently pending U.S. Provisional Application 61/480,797 filed Apr. 29, 2011 entitled SEALING GASKET. The above-identified U.S. Provisional Patent Applications from which priority is claimed are incorporated herein by reference in their entireties for all purposes. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to a gasket and method of attaching the gasket to a first pipe member to form a fluid-tight connection between the gasket, first pipe member, and a second pipe member. 
     BACKGROUND 
     For the transport of fluids that includes both liquids and gases, it is desirable to form a fluid-tight sealed connection when jointing two or more pipe sections together. Numerous applications exist for transporting drain or storm, potable, or waste water using pipe sections fabricated from thermoplastic materials such as polyethylene, polypropylene, polyvinyl chloride (PVC), high density polyethylene (HDPE), and the like. 
     One common pipe configuration for the transport of fluids includes dual-wall corrugated piping, having a smooth interior wall, optimizing fluid flow characteristics and a corrugated outer wall for enhanced strength and durability. Connecting the dual wall corrugated pipe sections is generally achieved by installing an oversized end of a first corrugated pipe section referred to as a bell over a spigot located at the end of a second corrugated pipe section. Seated in the one of the many corrugated sections or annular grooves of the spigot&#39;s outer diameter is typically a gasket that assists in forming a fluid-tight seal between the pipe sections. One example of a gasket design for such application, as well as for other purposes includes U.S. Pat. No. 7,469,905 that issued Dec. 30, 2008 and assigned to SpringSeal, Inc. (Streetsboro, Ohio) entitled PERMANENTLY LUBRICATED FILM GASKET AND METHOD OF MANUFACTURE (hereinafter “the &#39;905 patent”), which is incorporated herein by reference in its entirety. The elastomeric gasket contacts each of the pipe sections to form a sealed connection assembly between the pipe sections. 
     Typically, a large frictional force is encountered when the spigot and the gasket are inserted into the bell of the outer pipe section. As one end of the inner pipe is pushed into the enlarged end or bell of the outer pipe section&#39;s pipe connector, the gasket is at times, undesirably pulled from the groove by the large frictional force. When the pipe is not properly sealed, ground water may leak into the pipe or fluid may leak out of the pipe and contaminate the ground or area surrounding the pipe sections. 
     It is not uncommon for the joining sections of the corrugated pipe to be exposed to numerous forces causing stress to the gasket over the life of the connection. Such stress may allow the gasket to move from its desired location or allow debris to infiltrate the gasket seat, reducing the effectiveness of the sealing assembly connection. 
     SUMMARY 
     One example embodiment of the present disclosure includes an annular sealing gasket for forming a sealing connection between a first tubular member and a second tubular member. The annular sealing gasket comprises a flexible sealing portion adapted to form a sealing connection between a first tubular member and a second tubular member and a body region adapted for supporting the flexible sealing portion and anchoring the annular sealing gasket to a secured connection. The body region further comprises spaced first and second conical legs extending convergingly away from the body region transversely from the flexible sealing portion. 
     Another example embodiment of the present disclosure includes an annular sealing gasket for forming a sealing connection between a first tubular member and a second tubular member. The annular sealing gasket comprises a flexible sealing portion adapted to form a sealing connection between a first tubular member and a second tubular member. The annular sealing gasket also comprises a body region adapted for supporting the flexible sealing portion and anchoring the annular sealing gasket to a secured connection within a recess of one of the first and second tubular members during assembly. The body region has spaced first and second conical legs extending away from the body region. The annular sealing gasket includes a leading side that is covered first by the other of the first and second tubular members during assembly. The leading side of the annular sealing gasket is located opposite a trailing side. The flexible sealing portion is one of extruded and molded into the body region along the leading side. 
     Further example embodiment of the present disclosure includes an annular sealing gasket for forming a sealing connection between a first tubular member and a second tubular member, the annular sealing gasket comprises first and second flexible sealing portions adapted to form a sealing connection between a first tubular member and a second tubular member. The annular sealing gasket also comprises a body region adapted for supporting the flexible sealing portions and anchoring the annular sealing gasket to a secured connection within a recess of one of the first and second tubular members during assembly. The body region has spaced first and second conical legs extending away from the body region. The annular sealing gasket includes a leading side that is covered first by the other of the first and second tubular members during assembly. The leading side of the annular sealing gasket is located and spaced opposite a trailing side, the first flexible sealing portion being one of extruded and molded into the body region along the leading side and the second flexible sealing portion being one of extruded and molded into the body region along the trailing side. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The foregoing and other features and advantages of the present disclosure will become apparent to one skilled in the art to which the present disclosure relates upon consideration of the following description of the invention with reference to the accompanying drawings, wherein like reference numerals, unless otherwise described refer to like parts throughout the drawings and in which: 
         FIG. 1  is a cross-sectional partial perspective view of an annular sealing gasket constructed in accordance with one example embodiment of the present disclosure; 
         FIG. 2  is a cross-sectional partial perspective view of an annular sealing gasket constructed in accordance with another example embodiment of the present disclosure; 
         FIG. 3  is a cross sectional view of an annular gasket constructed in accordance with one example embodiment located in between two corrugations of a first pipe member and in a spigot of a first pipe member; 
         FIG. 4  is a cross-sectional partial perspective view of an annular sealing gasket constructed in accordance with another example embodiment of the present disclosure; 
         FIG. 5  is a partial perspective view of an annular sealing gasket constructed in accordance with another example embodiment of the present disclosure, the annular sealing gasket being nested in recess of a first pipe member; 
         FIG. 6  is a sectioned elevation view of  FIG. 5  illustrating a bell of a second pipe member approaching the annular sealing gasket; 
         FIG. 7  is a partial perspective view of an annular sealing gasket constructed in accordance with another example embodiment of the present disclosure, the annular sealing gasket being nested in recess of a first pipe member; 
         FIG. 8  is a sectioned elevation view of  FIG. 7  illustrating a bell of a second pipe member approaching the annular sealing gasket; 
         FIG. 9  is a partial perspective view of an annular sealing gasket constructed in accordance with another example embodiment of the present disclosure, the annular sealing gasket being nested in recess of a first pipe member; 
         FIG. 10  is a sectioned elevation view of  FIG. 9  illustrating a bell of a second pipe member approaching the annular sealing gasket; 
         FIG. 11  is an assembled view illustrating the annular sealing gasket of  FIG. 5  in a sealed position between first and second pipe members; 
         FIG. 12  is an assembled view illustrating the annular sealing gasket of  FIG. 7  in a sealed position between first and second pipe members; and 
         FIG. 13  is an assembled view illustrating the annular sealing gasket of  FIG. 9  in a sealed position between first and second pipe members. 
     
    
    
     DETAILED DESCRIPTION 
     Referring now to the figures generally wherein like numbered features shown therein refer to like elements having similar characteristics and operational properties throughout unless otherwise noted. The present disclosure relates to a gasket and method of attaching the gasket to a first pipe member to form a fluid-tight connection between the gasket, first pipe member, and a second pipe member. 
     Referring now to the figures and in particular to  FIG. 1  is a cross-sectional partial perspective view of annular sealing gasket  10  constructed in accordance with one example embodiment of the present disclosure. The sealing gasket  10  provides a fluid-tight seal  200  (see  FIG. 3 ) between a first tubular member  12  and second tubular member  14 . 
     In the illustrated example embodiment of  FIG. 3 , the first tubular member  12  has a plurality of annular grooves or corrugations  16  and annular crowns  18 . The second tubular member  14 , includes a smooth annular section  20 , such as a bell with a mouth  22  for receiving the first tubular member  12 . The first and second tubular members  12  and  14  could extend several feet (not shown), but are sectioned in the illustrated figures at point X. The sealing gasket  10 , is anchored in a spigot  19  located within a crown of the crest  18  formed by a single corrugation of the first pipe member  12 . 
     In an alternative example embodiment, the sealing gasket  10 ,  100  is larger in size and spans over the corrugations of the second pipe member  14  as illustrated in  FIG. 3  and forms a seal with a bell  20  of a second pipe member  15 . Whether the sealing gasket  10  or  100  is positioned within the corrugations  16  or a spigot  19 , a fluid-tight sealing connection  200  is achieved when an inner surface  24  of the bell compresses the sealing gasket  10 ,  100  between the two pipe members when the bell is advanced over the gasket in the direction of arrows “A”. 
     Once the fluid-tight connection  200  is made between the annular conforming integral gasket  10  and tubular members  12 ,  14 , fluids travel along the internal passage indicated by arrows L along the longitudinal axis “x” of the pipe members without leaking or entry of foreign objects or liquids. The ends of the two pipe members  12 ,  14  is illustrated by a gap  21 , sealed from leaking by the annular sealing gasket  10 . 
     The cross-sectional views of  FIGS. 1 and 2  of the annular sealing gaskets  10 ,  100  are typically circularly joined by welding two ends of the gasket together to form a continuous gasket constructed to a specified diameter as a function of the gasket application. In the illustrated embodiment, the inner diameter of the integral gasket  10  is slightly smaller than the smallest outer diameter profile of tubular member  12  to provide an interference type compression fit within the corrugation  16  or spigot  19 . 
     Further discussion of the process of welding ends of linear elastomeric gaskets to form the annular gaskets is found in U.S. Patent Publication Number 2007/0181654 filed Aug. 9, 2007 and assigned to SPRINGSEAL® (Streetsboro, Ohio) (hereinafter “the &#39;654 Publication”) entitled FLASHLESS WELDING METHOD AND APPARATUS, which is incorporated herein by reference in its entirety. In some applications, the diameters of the first and second tubular members  12 ,  14  could be five or more feet in diameter, requiring an equivalent sized diameter of the annular gasket  10 ,  100  to be used for that application. 
     In exemplary embodiment illustrated in  FIG. 1 , the annular sealing gasket  10  is formed from three different materials separated into a body region  30 , sealing portion  32 , and lubricated portion  34 . The body region  30  is made from a first material  40  having a relatively hard durometer. An example of a suitable material would be an elastomeric material having a durometer range for the body region  30  between 55 durometer on a Shore A scale and 50 durometer on a Shore D scale. Although elastomeric materials have been discussed, various polymers or rubbers having a durometer between 55 on a Shore A and 50 on a Shore D scale could also be used as a suitable first material without departing from the spirit and scope of the claimed invention. Yet another suitable example of a first material  40  includes high-density polyethylene (“HDPE”). 
     The sealing portion  32  is made from a second material  42  having a relatively pliable durometer relative to the first material  40 . An example of a suitable material would be an elastomeric material having a durometer range for the sealing portion between 40 and 60 durometer on a Shore A scale. An example of such material includes ASTM F477 Low Head material (ASTM F477 LH) which has a durometer of 50 plus or minus five. One company that makes ASTM F477 LH material is Advanced Elastomer Systems L.P. located in Akron, Ohio under their brand name SANTOPRENE®. Advanced Elastomer Sytems&#39; part number for SANTOPRENE® is 101-55. Multibase, a Dow Corning Company also produces ASTM F477 LH material under the part number 5904LC. Although elastomeric materials have been discussed, various polymers or rubbers having a durometer between 40 and 60 on a Shore A scale could also be used as a suitable second material without departing from the spirit and scope of the claimed invention. 
     The sealing gasket  10  includes a leading side  50  and a trailing side  52 . Extending along a portion of the leading side  50  is a third material  44  that forms a portion of the conforming gasket  10 . The third material  44  comprises a permanently lubricated composition. The permanently lubricated material  44  could be made from any material having a low coefficient of friction “COF” and more specifically a level of point five (0.5) or less. An example of such suitable material for the lubricated material  44  includes polyethylene or polypropylene which has an approximate COF of point three (0.3). The lubricated material  44  is relatively thin, having a thickness range between 0.001″ to 0.010″ inches, preferably ranging between 0.003″ to 0.005″ inches thick, and is typically applied along a substantial portion of the leading side  50  that would be in contact with the bell  20  of, for example the second tubular member  14  during assembly. The lubricated material  44  can be extruded onto the sealing gasket  10  simultaneously with the first and second materials  40 ,  42 , eliminating a need for a secondary operation for applying lubrication to the gasket. Further discussions relating to the application of a permanently lubricated material to a gasket is found in the &#39;905 patent. 
     In an alternative embodiment, the third material and/or second material  44 ,  42 , respectively are molded to the body region  30  of the first material  40 . Further discussion relating to the molding of a lubricated film and differing durometer materials into an elastomeric gasket can be found in U.S. Patent Publication Number 2007/0290455 filed Dec. 7, 2005 and entitled MOLDED GASKET AND METHOD OF MAKING (hereinafter “the &#39;455 Publication”), which is incorporated herein by reference in its entirety. In yet another exemplary embodiment, the third material  44  is sprayed onto the leading side  50  of the sealing member  32 . An example of a suitable sprayed lubricant includes poly(tetrafluoroethylene) or poly(tetrafluoroethene) (PTFE). 
     The sealing gasket  10  of  FIG. 1  further comprises a spine  60  formed within and extending from the body region  30 . The spine  60  of the body region  30  comprises a low planer upper surface  61  from a front end  62  to a rear end  64  that is integrated into the sealing portion  32 . Part of and extending radially from the body region  30  are spaced first and second legs  66 ,  68  respectively. The legs  66  and  68  are inverted cones extending converging away through tapered sides  63 ,  65  from the spine  60 , and are spaced by a medial region  70  at a lower surface  72  of the spine. 
     A front arcuate region  74  is formed about the body region  30  from a front lower surface  75  of the spine  60  to an apex  77  of the first leg  66 . A rear arcuate region  76  is formed about the body region  30  from a rear lower surface  81  of the spine to an apex  79  of the second leg  68 . 
     In the illustrated example embodiment of  FIG. 1 , the first leg  66  is radially shorter than the second leg  68 . In another example embodiment, the first and second legs  66 ,  68 , respectively are of equal length. In yet another example embodiment, the second leg  66  is radially shorter than the second leg  68 . 
     In one example embodiment, the front lower surface  75 , medial lower surface  70 , and rear lower surface  81  of the spine are all substantially parallel and separated by first and second legs  66 ,  68 , respectively. The substantially linear relationship provides a stiffening structure  90  resistant to lifting out of the corrugation  16  or spigot  19  during assembly of the pipe members  12 ,  14  with the sealing gasket  10  along a longitudinal direction represented by axis “x” in  FIG. 1 . 
     The sealing portion  32  of the gasket  10  comprises upper  94  and lower  96  members separated by a cavity  98 . The sealing portion  32  is integrally molded or extruded with the body region  30  and lubricated portion  34 . In one example embodiment, the gasket  10 ,  100  lacks a lubricated portion  34  formed by the third material  44 . 
     The sealing portion  32  during assembly advantageously forms a fluid-tight connection between the first and second pipe members by their compressing of the upper member  94  toward the lower member  96 . This compression sealing of the sealing member  32  is facilitated by the cavity  98 , that allows for the relative movement of the upper member  94  toward the lower member  96  as illustrated in the assembled view of  FIG. 3 . 
     As the mouth  22  of the bell  20  passes over the gasket  10 ,  100 , the inner surface  24  first engages the gasket at the sealing portion  32 . And in one example embodiment, the inner surface  24  first engages the lubricated portion  34  that assists in the interconnection of the pipe members through reduced friction. 
     During assembly, the sealing gasket  10 ,  100  is stretched around the perimeter of the first pipe member  12  for nesting within the spigot  19  as shown in  FIG. 3 . Or alternatively, the sealing gasket  10 ,  100  is stretch around the perimeter of the second pipe member  14  for seating a corrugation  16  as also shown in  FIG. 3 . The sealing gasket  10 ,  100  is compressed into the corrugation  16  or spigot  19  in the lateral direction such that the legs  66 ,  68  are displaced from a first position A to a second position A′ as shown in  FIG. 3 . This displacement, resulting from the double leg  66 ,  68 , construction during insertion, advantageously provides gripping strength to the sealing gasket  10 ,  100 . Resistant forces indicated by arrows “F” in  FIG. 3  along with the compression force indicated by arrow “C” radially toward the lateral axis creates a wedging effect about the inner walls  92  of the corrugation  16  or spigot  19  of  FIG. 3 . 
     The double leg  66 ,  68  construction spaced by medial region  70  in addition to providing gripping strength to the gaskets  10 ,  100 , also allows for proper seating of the gasket despite variations in the tolerances associated with the distance between inner walls  92 . That is, a solid anchor structure would lack the gripping power and tolerance forgiveness found in the geometrical construct of the sealing gasket  10 ,  100  example embodiments of  FIGS. 1 and 2 . 
     The low profile of the front end  62  of the gaskets  10 ,  100  also allows for enhanced gripping of the corrugation  16  and/or spigot  19 . In particular, the low profile design avoids frictional contact with the inner surface  24  of the bell  20  during assembly. As well, the lengthy lower spine surface  72  provides added holding strength during assembly resulting in part to the stiffening structure  90  from the substantially linear relationship about the legs. 
     Referring now to  FIG. 2  is a sealing gasket  100  constructed in accordance with another example embodiment. Similarly numbered features and elements shown in  FIG. 2  as that of  FIG. 1  refer to like elements having similar characteristics and operational properties unless otherwise noted. The sealing gasket  100  differs in one aspect from the example embodiment of  FIG. 1 , in that the annular legs  66  and  68  are constructed from the first material  40  and the spine  60  and sealing member  32  are constructed from the second material  42 . The first material  40 , second material  42 , and third material  44  in the example embodiment of  FIG. 2  have the same material characteristics and suitable examples as previously described. In an alternative example embodiment, the sealing gasket  100  lacks a lubricated portion  34  and third material  44 . 
     By forming the spine  60  and sealing member  32  from the second lower durometer material  42  as illustrated in  FIG. 2 , advantageously this provides for additional flexing and stretching the gasket  100  about the inner pipe member prior to seating the gasket into the corrugations  16  or spigot  19 , while the first material  40  is maintains the gripping strength in the legs  66 ,  68 , as previously described. 
     The annular spine  60  and annular sealing member  32  of the sealing gasket  100  formed from the second material  42  includes an overall diameter slightly smaller than the outer diameter of the spigot  19  or corrugation  16 . As a result, the annular sealing gasket  100  during assembly is elastically stretched over the spigot  19  or corrugation  16  such that upon release, the legs  66 ,  68  snap into the corrugation or spigot. The reduction in size of the sealing gasket  100  diameter is roughly 96% of the crest of the spigot  19  or corrugation  16 . Stated another way, for a twelve (12″) inch outer most diameter at the spigot  19  or corrugation  16 , the diameter of the gasket  100  would be undersized to a diameter of approximately eleven point five (11.5″) inches. 
     The illustrated example embodiment of  FIG. 2  advantageously allows for the required flexing of the elements formed or extruded from the second material  42  that are parallel (spine  60  and sealing member  32 ) with the longitudinal axis x of the annular sealing gasket  100 , while allowing the elements formed from the first material  40  (annular legs  66 ,  68 ) transverse to the longitudinal axis x of the annular sealing gasket  100  to remain rigid for gripping strength. 
     In an alternative example embodiment, the flexible nature of the second material is enhanced by adding a flexing agent to the annular sealing gasket&#39;s  100  composition during the forming process. For polypropylene, an example of a suitable flexing agent is a commercial product called Vistamaxx manufactured by Exxon Mobile Chemical Company. For polyethylene, a suitable flexing agent is a commercial product called Engage manufactured by Dow Chemical. A suitable formulation in the composition of the second material  42  of the gasket  100  in one example embodiment is approximately 30% flexing agent and 70% rigid plastic having a durometer between 40 and 50 on a Shore D scale. 
     In a performance test, a gasket  100  having the 70/30 plastic/flexing agent composition as a second material  42  was pressure tested without any welding or permanent connections to the first or second tubular members  12  and  14 . That is, the gasket  100  was secured to a twelve inch inner pipe  12  solely by the radial forces “F” compressive forces “C” achieved through the under sizing of the gasket (11.5″ inch diameter for 12″ inch diameter pipe), the gasket&#39;s geometrical configuration, and flexing agent used in its composition of the second material  42 . During the test, the gasket  100  exceeded thirty minutes without a leak at a pressure of thirty (30) psi. 
     Illustrated in  FIG. 4  is an annular sealing gasket  300  constructed in accordance with another example embodiment of the present disclosure. The sealing gasket  300  comprises a single material  302  for forming the entire gasket except for the lubricated portion  44  made from the third material  44 . The single material  302  in one example embodiment is the same as the second material  42  and those ranges and suitable examples provided with respect to and described in  FIG. 1 . In yet another example embodiment the single material  302  is the same as the first material  40  and those ranges and suitable examples provided with respect to and described in  FIG. 1 . While yet another example embodiment of the annular sealing gasket  300  includes a gasket that is extruded or molded without the lubricated portion  34  from the third material  44 . 
       FIG. 5  is a partial perspective view of an annular sealing gasket  400  constructed in accordance with another example embodiment of the present disclosure. The annular sealing gasket  400 , as illustrated in  FIGS. 5 and 6  is nested in a spigot or recess  19  of a first pipe member  12 . The sealing gasket  400  provides a fluid-tight seal  499  (see  FIG. 11 ) between the first pipe member  12  and second pipe member  14 . 
     In the illustrated example embodiment of  FIGS. 5 and 6 , the first pipe member  12  has a plurality of annular grooves or corrugations  16  and annular crowns  18 . The second pipe member includes a smooth annular section  20 , such as a bell with a mouth  22  for receiving the sealing gasket  400  and first pipe member  12 . The first and second tubular members could extend several feet (not shown), but are section in the illustrated example of  FIG. 6  at points X. The sealing gasket  400 , is anchored in the spigot  19  located within a crown of the crest  18  formed by a single corrugation of the first pipe member  12 . 
     In an alternative embodiment, the sealing gasket  400  is larger in size and spans over the corrugations  16  of the first pipe member  12  between the crowns  18  and forms a seal with the bell of the second pipe member  14 . Whether the sealing gasket  400  is positioned within the corrugations  16  or spigot  19 , a fluid-tight sealing connection  499  is achieved between the two pipe members  12 ,  14  when the bell is advanced over the gasket in the direction of the arrow “A”. 
     Once the fluid-tight connection  499  is made between the annular conforming integral gasket  400  and tubular members  12 ,  14 , fluids travel along the integral passage indicated by arrows “L” along the longitudinal axis “x” of the pipe members without leaking or entry of foreign objects or liquids. 
     Ends  402  and  404  of the gasket  400  shown in  FIG. 5  are typically circularly joined by welding the two ends of the gasket together to form a continuous gasket constructed to a specified diameter as a function of the gasket application. In the illustrated example embodiment, the inner diameter of the integral  400  is slightly smaller than the smallest outer diameter profile of the tubular member  12  to provide an interference type compression fit within the corrugation  16  or spigot  19 . 
     Further discussion of the process of welding ends of linear elastomeric gaskets to form the annular gaskets is found in U.S. Patent Publication No. 2007/0181654 filed Aug. 9, 2007 and assigned to SPRINGSEAL® (Streestsboro, Ohio) hereinafter “the &#39;654 Publication”) entitled FLASHLESS WELDING METHOD AND APPARATUS, which is incorporated herein by reference in its entirety. In some applications, the diameters of the first and second tubular members  12 ,  14  could be five or more feet in diameter, requiring an equivalent sized diameter of the annular gasket  400  to be used for that application. 
     In the exemplary embodiment of  FIGS. 5 ,  6 , and  11 , the annular sealing gasket gasket  400  is formed from two different materials separated into a body region  30  and sealing portion  32 . The body region  30  is made from a first material  40  having a relatively hard durometer. An example of suitable material would be an elastomeric material having a durometer range for the body region  30  between 55 durometer on a Shore A scale and a 50 durometer on a Shore D scale. Although elastomeric materials have been discussed, various polymers or rubbers having a durometer between 55 on a Shore A and 50 on a Shore D scale could be used as a suitable first material without departing from the spirit and scope of the claimed disclosure. Yet another suitable example of a first material  40  includes high-density polyethylene (“HDPE”). 
     In an alternative example embodiment, the body region  30 , and particularly the first material  40  comprises a durometer value ranging between 70 and 90 on a Shore A scale, and more specifically a Shore A value of 80. Such Shore A value of such range in one example embodiment comprises 80% weight per unit volume g/cm 3  ASTM F477 grade material or SANTOPRENE® and 20% polypropylene weight per unit volume g/cm 3 . And yet in another example embodiment, the second material  40  is formed from only 80% weight per unit volume g/cm 3  ASTM F477 grade material or SANTOPRENE® and 20% polypropylene weight per unit volume g/cm 3 . 
     The first material  40  range between 70 and 90 on a Shore A scale, and more specifically a Shore A value of 80 provides a more flexible anchor for the body region  30 , advantageously allowing longer legs  66 ,  68  that are needed for larger gaskets. This enables legs  66 ,  68  for stretching into deeper spigots  19 , thus advantageously resisting pull-out or separation. 
     In a performance test, an annular gasket  400  having the Shore A value ranging between 70 and 90 in composition as a first material  40  was pressure tested without any welding or permanent connections to the first or second tubular members  12  and  14 . That is, the gasket  400  was secured to an inner pipe  12  solely by the radial forces “F” compressive forces “C” achieved through the gasket&#39;s geometrical configuration and in the composition of the second material  40 . During the test, the gasket  400  exceeded thirty minutes without a leak at a pressure of thirty (30) psi or movement of the gasket  400  out of the spigot  19 . 
     The higher tensile strength and lower elongation properties found in the annular gasket  400  comprising the Shore A value ranging between 70 and 90 on a Shore A scale in the first material  40  was further advantageously found to posses resiliency not obtained in conventional gaskets. That is, the gasket  400  is capable of resealing itself against the bell of a piping member after a portion of the gasket has been dislodged by higher water pressure once the higher water pressure subsides. The conventional gaskets having a first material durometer value 40-50 D on a Shore D scale. 
     The sealing portion  32  is made from a second material  42  having a relatively pliable durometer relative to the first material  40 . An example of a suitable material would be an elastomeric material having a durometer range for the sealing portion between 40 and 60 durometer on a Shore A scale. An example of such material includes ASTM F477 Low Head material (ASTM F477), which has a durometer of 50 plus or minus five. One company that makes ASTM F477 LH material is Advanced Elastomer Systems L.P. located in Akron, Ohio under their brand name SANTOPRENE®. Advanced Elastomer Systems&#39; part number for SANTOPRENE® is 101-55. Multibase, a Dow Corning Company also produces ASTM F477 LH material under the part number 5904LC. Although elastomeric materials have been discussed, various polymers or rubbers having a durometer between 40 and 60 on a Shore A scale could be used as a suitable second material without departing from the spirit and scope of the claimed disclosure. 
     The sealing gasket  400  includes a leading side  50  and a trailing side  52 . In one example embodiment, extending along the leading side of the gasket  400  is a third material (not shown) that forms a portion of the conforming gasket comprising a permanently lubricated composition. The permanently lubricated material could be made from any material having a low coefficient of friction “COF” and more specifically a level of point five 0.5 or less. An example of such suitable material for the lubricated material includes polyethylene or polypropylene, which has an approximate COF of point three (0.3). The lubricated material is relatively thin, having a thickness range between 0.001″ to 0.010″ inches, preferably ranging between 0.003″ to 0.005″ inches thick, and is typically applied along a substantial portion of the leading side  50  that would be in contact with the bell  20  of, for example the second tubular member  14  during assembly. The lubricated material can be extruded into the sealing gasket  400  simultaneously with the first and second materials  40 ,  42 , eliminating the need for a secondary operation for applying lubrication to the gasket. Further discussions relating to the application of a permanently lubricated material to a gasket is found in the &#39;905 patent. 
     In an alternative embodiment, the third material and/or second material  42  are molded to the body region  30  of the first material  40 . Further discussion relating to the molding of a lubricated film and differing durometer materials into an elastomeric gasket can be found in U.S. Patent Publication Number 2007/0290455 filed Dec. 7, 2005 and entitled MOLDED GASKET AND METHOD OF MAKING (hereinafter “the &#39;455 Publication”), which is incorporated herein by reference in its entirety. In yet another exemplary embodiment, the third material is sprayed onto the leading side  50  of the sealing member  32 . An example of a suitable sprayed lubricant includes poly(tetrafluoroethylene) or poly(tetrafluoroethene) (PTFE). 
     The sealing gasket  400  of  FIGS. 5 ,  6 , and  11  further comprises a spine  60  formed within and extending from the body region  30 . The spine  60  of the body region  30  comprises a low planer upper surface  61  from a front end  62  to a rear end  64  that is integrated into the sealing portion  32 . Part of, and extending radially from the body region  30  are spaced first and second legs  66 ,  68  respectively. The legs  66  and  68  are inverted cones extending converging away through tapered sides  63 ,  65  from spine  60 , and are spaced by a medial region  70  at a lower surface of the spine. 
     A front arcuate region  74  is formed about the body region  30  from a front lower surface of the spine  60  to an apex  77  of the first leg  66 . A rear arcuate region  76  is formed about the body region  30  from a rear lower surface  81  of the spine to an apex  79  of the second leg  68 . 
     In one example embodiment, the front lower surface  75 , medial lower surface  70 , and rear lower surface  81  of the spine are all substantially parallel and separated by first and second legs  66 ,  68 , respectively. The substantially linear relationship provides a stiffening structure  90  resistant to lifting out of the corrugation  16  or spigot  19  during assembly of the pipe members  12 ,  14  with the sealing gasket  10  along a longitudinal direction represented by axis “x” in  FIG. 6 . 
     The sealing portion  32  of the gasket  400  comprises upper  94  and lower  96  members separated by a cavity  98 . The sealing portion  32  is integrally molded or extruded with the body region. The sealing portion  32  during assembly advantageously forms a fluid-tight seal between the first and second pipe members  12 ,  14 , by their compressing of the upper member  94  toward the lower member  96 . This compression sealing of the sealing member  32  is facilitated by the cavity  98 , that allows for the relative movement of the upper member  94  toward the lower member  96  as illustrated in the assembled view of  FIG. 11 . 
     As the mouth  22  of the bell  20  passes over the gasket  400 , the inner surface  24  first engages the gasket at the sealing portion  32 . And, in one example embodiment, the inner surface  24  first engages the lubricated portion on the leading side  50  that assists in the interconnection of the pipe members through the reduced friction. 
     During assembly, the sealing gasket  400  is stretched around the perimeter of the first pipe member  12  for nesting within the spigot  19  as shown in  FIG. 6 . Or alternatively, the sealing gasket  400  is stretched around the perimeter of the first pipe member  12  for seating in a corrugation  16 . The sealing gasket when relaxed is compressed into the corrugation  16  or spigot  19  in the lateral or y-axis direction, causing one or both legs  66 ,  68  to wedge within the recess  19 . 
     The annular spine  60  and the annular sealing member  32  of the sealing gasket  400  formed from the first and second materials  40 ,  42  include an overall diameter slightly smaller than the outer diameter of the spigot recess  19  or corrugation  16 . As a result, the annular sealing gasket  400  during assembly is elastically stretched over the spigot  19  or corrugation  16  such that upon release, the legs  66 ,  68  snap into the corrugation or spigot. The reduction in size of the sealing gasket  400  is roughly 96% of the crest of the spigot  19  or corrugation  16 . Stated another way, for a twelve (12″) inch out most diameter at the spigot  19  or corrugation  16 , the diameter of the gasket  400  would be undersized to a diameter of approximately eleven point five (11.5″) inches. 
     In an alternative example embodiment, the flexible nature of the gasket  400  is enhanced by adding a flexing agent  410  to the annular sealing gasket&#39;s composition during the extruding process. For polypropylene, an example of a suitable flexing agent is a commercial product called Vistamaxx manufactured by Exxon Mobile Chemical Company. For polyethylene, a suitable flexing agent is a commercial product called Engage manufactured by Dow Chemical. A suitable formulation in the composition of the materials forming the gasket  400  is one example embodiment is approximately 30% by weight per unit volume g/cm 3  flexing agent and 70% by weight per unit volume g/cm 3  rigid plastic having a durometer between 40 and 50 on a Shore D scale. In another example embodiment, the rigid plastic comprises polypropylene and the flexing agent comprises a propylene-based elastomer. In yet another example embodiment, the body region  30  formed from only rigid plastic consisting of polypropylene and the flexing agent consisting of a propylene-based elastomer. 
       FIG. 7  is a partial perspective view of an annular sealing gasket  500  constructed in accordance with another example embodiment of the present disclosure. The annular sealing gasket  500 , as illustrated in  FIGS. 7 and 8  is nested in a spigot or recess  19  of a first pipe member  12 . The sealing gasket  500  provides a fluid-tight seal  599  (see  FIG. 12 ) between the first pipe member  12  and second pipe member  14 . 
     In the illustrated example embodiment of  FIGS. 7 and 8 , the first pipe member  12  has a plurality of annular grooves or corrugations  16  and annular crowns  18 . The second pipe member includes a smooth annular section  20 , such as a bell with a mouth  22  for receiving the sealing gasket  500  and first pipe member  12 . The first and second tubular members could extend several feet (not shown), but are section in the illustrated example of  FIG. 8  at points X. The sealing gasket  500 , is anchored in the spigot  19  located within a crown of the crest  18  formed by a single corrugation of the first pipe member  12 . 
     In an alternative embodiment, the sealing gasket  500  is larger in size and spans over the corrugations  16  of the first pipe member  12  between the crowns  18  and forms a seal with the bell of the second pipe member  14 . Whether the sealing gasket  500  is positioned within the corrugations  16  or spigot  19 , a fluid-tight sealing connection  599  is achieved between the two pipe members  12 ,  14  when the bell is advanced over the gasket in the direction of the arrow “A”. 
     Once the fluid-tight connection  599  is made between the annular conforming integral gasket  500  and tubular members  12 ,  14 , fluids travel along the integral passage indicated by arrows “L” along the longitudinal axis “x” of the pipe members without leaking or entry of foreign objects or liquids. 
     Ends  502  and  504  of the gasket  500  shown in  FIG. 7  are typically circularly joined by welding the two ends of the gasket together to form a continuous gasket constructed to a specified diameter as a function of the gasket application. In the illustrated example embodiment, the inner diameter of the integral  500  is slightly smaller than the smallest outer diameter profile of the tubular member  12  to provide an interference type compression fit within the corrugation  16  or spigot  19 . 
     Further discussion of the process of welding ends of linear elastomeric gaskets to form the annular gaskets is found in U.S. Patent Publication No. 2007/0181654 filed Aug. 9, 2007 and assigned to SPRINGSEAL® (Streestsboro, Ohio) hereinafter “the &#39;654 Publication”) entitled FLASHLESS WELDING METHOD AND APPARATUS, which is incorporated herein by reference in its entirety. In some applications, the diameters of the first and second tubular members  12 ,  14  could be five or more feet in diameter, requiring an equivalent sized diameter of the annular gasket  500  to be used for that application. 
     In the exemplary embodiment of  FIGS. 7 ,  8 , and  12 , the annular sealing gasket  500  is formed from two different materials separated into a body region  30  and sealing portion  32 . The body region  30  is made from a first material  40  having a relatively hard durometer. An example of suitable material would be an elastomeric material having a durometer range for the body region  30  between 55 durometer on a Shore A scale and a 50 durometer on a Shore D scale. Although elastomeric materials have been discussed, various polymers or rubbers having a durometer between 55 on a Shore A and 50 on a Shore D scale could be used as a suitable first material without departing from the spirit and scope of the claimed disclosure. Yet another suitable example of a first material  40  includes high-density polyethylene (“HDPE”). 
     The sealing portion  32  is made from a second material  42  having a relatively pliable durometer relative to the first material  40 . An example of a suitable material would be an elastomeric material having a durometer range for the sealing portion between 40 and 60 durometer on a Shore A scale. An example of such material includes ASTM F477 Low Head material (ASTM F477), which has a durometer of 50 plus or minus five. One company that makes ASTM F477 LH material is Advanced Elastomer Systems L.P. located in Akron, Ohio under their brand name SANTOPRENE®. Advanced Elastomer Systems&#39; part number for SANTOPRENE® is 101-55. Multibase, a Dow Corning Company also produces ASTM F477 LH material under the part number 5904LC. Although elastomeric materials have been discussed, various polymers or rubbers having a durometer between 40 and 60 on a Shore A scale could be used as a suitable second material without departing from the spirit and scope of the claimed disclosure. 
     The sealing gasket  500  includes a leading side  50  and a trailing side  52 . In one example embodiment, extending along the leading side of the gasket  500  is a third material (not shown) that forms a portion of the conforming gasket comprising a permanently lubricated composition. The permanently lubricated material could be made from any material having a low coefficient of friction “COF” and more specifically a level of point five 0.5 or less. An example of such suitable material for the lubricated material includes polyethylene or polypropylene, which has an approximate COF of point three (0.3). The lubricated material is relatively thin, having a thickness range between 0.001″ to 0.010″ inches, preferably ranging between 0.003″ to 0.005″ inches thick, and is typically applied along a substantial portion of the leading side  50  that would be in contact with the bell  20  of, for example the second tubular member  14  during assembly. The lubricated material can be extruded into the sealing gasket  500  simultaneously with the first and second materials  40 ,  42 , eliminating the need for a secondary operation for applying lubrication to the gasket. Further discussions relating to the application of a permanently lubricated material to a gasket is found in the &#39;905 patent. 
     In an alternative embodiment, the third material and/or second material  42  are molded to the body region  30  of the first material  40 . Further discussion relating to the molding of a lubricated film and differing durometer materials into an elastomeric gasket can be found in U.S. Patent Publication Number 2007/0290455 filed Dec. 7, 2005 and entitled MOLDED GASKET AND METHOD OF MAKING (hereinafter “the &#39;455 Publication”), which is incorporated herein by reference in its entirety. In yet another exemplary embodiment, the third material is sprayed onto the leading side  50  of the sealing member  32 . An example of a suitable sprayed lubricant includes poly(tetrafluoroethylene) or poly(tetrafluoroethene) (PTFE). 
     The sealing gasket  500  of  FIGS. 7 ,  8 , and  12  further comprises a spine  60  formed within and extending from the body region  30 . The spine  60  of the body region  30  comprises a low planer upper surface  61  from a front end  62  to a rear end  64 . The front end  62  is integrated into the sealing portion  32  by molding or co-extruding. Part of, and extending radially from the body region  30  are spaced first and second legs  66 ,  68  respectively. The legs  66  and  68  are inverted cones extending converging away through tapered sides  63 ,  65  from spine  60 , and are spaced by a medial region  70  at a lower surface of the spine. 
     A front arcuate region  74  is formed about the body region  30  from a front lower surface of the spine  60  to an apex  77  of the first leg  66 . A rear arcuate region  76  is formed about the body region  30  from a rear lower surface  81  of the spine to an apex  79  of the second leg  68 . 
     In one example embodiment, the front lower surface  75 , medial lower surface  70 , and rear lower surface  81  of the spine are all substantially parallel and separated by first and second legs  66 ,  68 , respectively. The substantially linear relationship provides a stiffening structure  90  resistant to lifting out of the corrugation  16  or spigot  19  during assembly of the pipe members  12 ,  14  with the sealing gasket  10  along a longitudinal direction represented by axis “x” in  FIG. 8 . 
     The sealing portion  32  of the gasket  500  comprises upper  94  and lower  96  members separated by a cavity  98 . The sealing portion  32  is integrally molded or extruded with the body region  30 . The sealing portion  32  during assembly advantageously forms a fluid-tight seal between the first and second pipe members  12 ,  14 , by their compressing of the upper member  94  toward the lower member  96 . This compression sealing of the sealing member  32  is facilitated by the cavity  98  and transverse inclined surface  508  forming the leading edge of the sealing member as shown by arrow W, that allows for the relative movement of the upper member  94  toward the lower member  96  as illustrated in the assembled view of  FIG. 12 . The transverse inclined surface at the front of the body region  30  on the leading side  50  forms a novel wedge between the pipe members  12 ,  14  during assembly, advantageously proving a fluid tight seal. This transverse inclined surface  508  provides a resultant force between the pipe members normal to the surface as shown by force F. 
     As the mouth  22  of the bell  20  passes over the gasket  500 , the inner surface  24  first engages the gasket at the sealing portion  32 . And, in one example embodiment, the inner surface  24  first engages the lubricated portion on the leading side  50  that assists in the interconnection of the pipe members through the reduced friction. 
     During assembly, the sealing gasket  500  is stretched around the perimeter of the first pipe member  12  for nesting within the spigot  19  as shown in  FIG. 8 . Or alternatively, the sealing gasket  500  is stretched around the perimeter of the first pipe member  12  for seating in a corrugation  16 . The sealing gasket when relaxed is compressed into the corrugation  16  or spigot  19  in the lateral or y-axis direction, causing one or both legs  66 ,  68  to wedge within the recess  19 . 
     The annular spine  60  and the annular sealing member  32  of the sealing gasket  500  formed from the first and second materials  40 ,  42  include an overall diameter slightly smaller than the outer diameter of the spigot recess  19  or corrugation  16 . As a result, the annular sealing gasket  500  during assembly is elastically stretched over the spigot  19  or corrugation  16  such that upon release, the legs  66 ,  68  snap into the corrugation or spigot. The reduction in size of the sealing gasket  500  is roughly 96% of the crest of the spigot  19  or corrugation  16 . Stated another way, for a twelve (12″) inch out most diameter at the spigot  19  or corrugation  16 , the diameter of the gasket  500  would be undersized to a diameter of approximately eleven point five (11.5″) inches. 
     In an alternative example embodiment, the flexible nature of the gasket  500  is enhanced by adding a flexing agent  510  to the annular sealing gasket&#39;s composition during the extruding process. For polypropylene, an example of a suitable flexing agent is a commercial product called Vistamaxx manufactured by Exxon Mobile Chemical Company. For polyethylene, a suitable flexing agent is a commercial product called Engage manufactured by Dow Chemical. A suitable formulation in the composition weight per unit volume (“w/v”) of the materials forming the gasket  500  is one example embodiment is approximately 30% by weight per unit volume g/cm 3  flexing agent and 70% by weight per unit volume g/cm 3  rigid plastic having a durometer between 40 and 50 on a Shore D scale. In another example embodiment, the rigid plastic comprises polypropylene and the flexing agent comprises a propylene-based elastomer. In yet another example embodiment, the body region  30  is formed from only rigid plastic consisting of polypropylene and the flexing agent consisting of a propylene-based elastomer. While yet in another example embodiment, the body region  30  is formed from only rigid plastic consisting of polyethylene and the flexing agent consisting of a polyolefin elastomer. 
       FIG. 9  is a partial perspective view of an annular sealing gasket  600  constructed in accordance with another example embodiment of the present disclosure. The annular sealing gasket  600 , as illustrated in  FIGS. 9 and 10  is nested in a spigot or recess  19  of a first pipe member  12 . The sealing gasket  600  provides a fluid-tight seal  699  (see  FIG. 13 ) between the first pipe member  12  and second pipe member  14 . 
     In the illustrated example embodiment of  FIGS. 9 and 10 , the first pipe member  12  has a plurality of annular grooves or corrugations  16  and annular crowns  18 . The second pipe member includes a smooth annular section  20 , such as a bell with a mouth  22  for receiving the sealing gasket  600  and first pipe member  12 . The first and second tubular members could extend several feet (not shown), but are section in the illustrated example of  FIG. 10  at points X. The sealing gasket  600 , is anchored in the spigot  19  located within a crown of the crest  18  formed by a single corrugation of the first pipe member  12 . 
     In an alternative embodiment, the sealing gasket  600  is larger in size and spans over the corrugations  16  of the first pipe member  12  between the crowns  18  and forms a seal with the bell of the second pipe member  14 . Whether the sealing gasket  600  is positioned within the corrugations  16  or spigot  19 , a fluid-tight sealing connection  699  is achieved between the two pipe members  12 ,  14  when the bell is advanced over the gasket in the direction of the arrow “A”. 
     Once the fluid-tight connection  699  is made between the annular conforming integral gasket  600  and tubular members  12 ,  14 , fluids travel along the integral passage indicated by arrows “L” along the longitudinal axis “x” of the pipe members without leaking or entry of foreign objects or liquids. 
     Ends  602  and  604  of the gasket  600  shown in  FIG. 9  are typically circularly joined by welding the two ends of the gasket together to form a continuous gasket constructed to a specified diameter as a function of the gasket application. In the illustrated example embodiment, the inner diameter of the integral  600  is slightly smaller than the smallest outer diameter profile of the tubular member  12  to provide an interference type compression fit within the corrugation  16  or spigot  19 . 
     Further discussion of the process of welding ends of linear elastomeric gaskets to form the annular gaskets is found in U.S. Patent Publication No. 2007/0181654 filed Aug. 9, 2007 and assigned to SPRINGSEAL® (Streestsboro, Ohio) hereinafter “the &#39;654 Publication”) entitled FLASHLESS WELDING METHOD AND APPARATUS, which is incorporated herein by reference in its entirety. In some applications, the diameters of the first and second tubular members  12 ,  14  could be five or more feet in diameter, requiring an equivalent sized diameter of the annular gasket  600  to be used for that application. 
     In the exemplary embodiment of  FIGS. 9 ,  10 , and  13 , the annular sealing gasket  600  is formed from two different materials separated into a body region  30  and first and second sealing portions  32 A and  32 B. The body region  30  is made from a first material  40  having a relatively hard durometer. An example of suitable material would be an elastomeric material having a durometer range for the body region  30  between 55 durometer on a Shore A scale and a 50 durometer on a Shore D scale. Although elastomeric materials have been discussed, various polymers or rubbers having a durometer between 55 on a Shore A and 50 on a Shore D scale could be used as a suitable first material without departing from the spirit and scope of the claimed disclosure. Yet another suitable example of a first material  40  includes high-density polyethylene (“HDPE”). 
     The sealing portions  32 A,  32 B are made from a second material  42  having a relatively pliable durometer relative to the first material  40 . An example of a suitable material would be an elastomeric material having a durometer range for the sealing portion between 40 and 60 durometer on a Shore A scale. An example of such material includes ASTM F477 Low Head material (ASTM F477), which has a durometer of 50 plus or minus five. One company that makes ASTM F477 LH material is Advanced Elastomer Systems L.P. located in Akron, Ohio under their brand name SANTOPRENE®. Advanced Elastomer Systems&#39; part number for SANTOPRENE® is 101-55. Multibase, a Dow Corning Company also produces ASTM F477 LH material under the part number 5904LC. Although elastomeric materials have been discussed, various polymers or rubbers having a durometer between 40 and 60 on a Shore A scale could be used as a suitable second material without departing from the spirit and scope of the claimed disclosure. 
     The sealing gasket  600  includes a leading side  50  and a trailing side  52 . In one example embodiment, extending along the leading side of the gasket  600  is a third material (not shown) that forms a portion of the conforming gasket comprising a permanently lubricated composition. The permanently lubricated material could be made from any material having a low coefficient of friction “COF” and more specifically a level of point five 0.5 or less. An example of such suitable material for the lubricated material includes polyethylene or polypropylene, which has an approximate COF of point three (0.3). The lubricated material is relatively thin, having a thickness range between 0.001″ to 0.010″ inches, preferably ranging between 0.003″ to 0.005″ inches thick, and is typically applied along a substantial portion of the leading side  50  that would be in contact with the bell  20  of, for example the second tubular member  14  during assembly. The lubricated material can be extruded into the sealing gasket  600  simultaneously with the first and second materials  40 ,  42 , eliminating the need for a secondary operation for applying lubrication to the gasket. Further discussions relating to the application of a permanently lubricated material to a gasket is found in the &#39;905 patent. 
     In an alternative embodiment, the third material and/or second material  42  are molded to the body region  30  of the first material  40 . Further discussion relating to the molding of a lubricated film and differing durometer materials into an elastomeric gasket can be found in U.S. Patent Publication Number 2007/0290455 filed Dec. 7, 2005 and entitled MOLDED GASKET AND METHOD OF MAKING (hereinafter “the &#39;455 Publication”), which is incorporated herein by reference in its entirety. In yet another exemplary embodiment, the third material is sprayed onto the leading side  50  of the sealing members  32 A and  32 B. An example of a suitable sprayed lubricant includes poly(tetrafluoroethylene) or poly(tetrafluoroethene) (PTFE). 
     The sealing gasket  600  of  FIGS. 9 ,  10 , and  13  further comprises a spine  60  formed within and extending from the body region  30 . The spine  60  of the body region  30  comprises a low planer upper surface  61  from a front end  62  to a rear end  64 . The front end  62  and rear end  64  are integrated into first and second sealing portions  32 A,  32 B, respectively by molding or co-extruding. Part of, and extending radially from the body region  30  are spaced first and second legs  66 ,  68  respectively. The legs  66  and  68  are inverted cones extending converging away through tapered sides  63 ,  65  from spine  60 , and are spaced by a medial region  70  at a lower surface of the spine. 
     A front arcuate region  74  is formed about the body region  30  from a front lower surface of the spine  60  to an apex  77  of the first leg  66 . A rear arcuate region  76  is formed about the body region  30  from a rear lower surface  81  of the spine to an apex  79  of the second leg  68 . 
     In one example embodiment, the front lower surface  75 , medial lower surface  70 , and rear lower surface  81  of the spine are all substantially parallel and separated by first and second legs  66 ,  68 , respectively. The substantially linear relationship provides a stiffening structure  90  resistant to lifting out of the corrugation  16  or spigot  19  during assembly of the pipe members  12 ,  14  with the sealing gasket  10  along a longitudinal direction represented by axis “x” in  FIG. 10 . 
     The first and second sealing portions  32 A and  32 B of the gasket  600  comprises upper  94  and lower  96  members separated by a cavity  98 . The sealing portion  32  is integrally molded or extruded with the body region  30 . The sealing portions  32 A and  32 B during assembly advantageously forms a fluid-tight seal between the first and second pipe members  12 ,  14 , by their compressing of the upper member  94  toward the lower member  96 . This compression sealing of the sealing members  32  is facilitated by the cavities  98  and transverse inclined surface  608  forming the leading edge of the first sealing member  32 A as shown by arrow W, that allows for the relative movement of the upper member  94  toward the lower member  96  as illustrated in the assembled view of  FIG. 13 . The transverse inclined surface at the front of the body region  30  on the leading side  50  along with dual sealing members  32 A and  32 B separated by body region  30  forms a novel wedge between the pipe members  12 ,  14  during assembly, advantageously proving a fluid tight seal. This transverse inclined surface  608  provides a resultant force between the pipe members normal to the surface as shown by force F. 
     As the mouth  22  of the bell  20  passes over the gasket  600 , the inner surface  24  first engages the gasket at the sealing portions  32 A and  32 B. And, in one example embodiment, the inner surface  24  first engages the lubricated portion on the leading side  50  of either or both of the sealing members  32 A and  32 B that assists in the interconnection of the pipe members through the reduced friction. 
     During assembly, the sealing gasket  600  is stretched around the perimeter of the first pipe member  12  for nesting within the spigot  19  as shown in  FIG. 10 . Or alternatively, the sealing gasket  600  is stretched around the perimeter of the first pipe member  12  for seating in a corrugation  16 . The sealing gasket when relaxed is compressed into the corrugation  16  or spigot  19  in the lateral or y-axis direction, causing one or both legs  66 ,  68  to wedge within the recess  19 . 
     The annular spine  60  and the annular sealing members  32  of the sealing gasket  600  formed from the first and second materials  40 ,  42  includes an overall diameter slightly smaller than the outer diameter of the spigot recess  19  or corrugation  16 . As a result, the annular sealing gasket  600  during assembly is elastically stretched over the spigot  19  or corrugation  16  such that upon release, the legs  66 ,  68  snap into the corrugation or spigot. The reduction in size of the sealing gasket  600  is roughly 96% of the crest of the spigot  19  or corrugation  16 . Stated another way, for a twelve (12″) inch out most diameter at the spigot  19  or corrugation  16 , the diameter of the gasket  600  would be undersized to a diameter of approximately eleven point five (11.5″) inches. 
     In an alternative example embodiment, the flexible nature of the gasket  600  is enhanced by adding a flexing agent  610  to the annular sealing gasket&#39;s composition during the extruding process. For polypropylene, an example of a suitable flexing agent is a commercial product called Vistamaxx manufactured by Exxon Mobile Chemical Company. For polyethylene, a suitable flexing agent is a commercial product called Engage manufactured by Dow Chemical. A suitable formulation in the composition of the materials forming the gasket  600  is one example embodiment is approximately 30% by weight per unit volume g/cm 3  flexing agent and 70% by weight per unit volume g/cm 3  rigid plastic having a durometer between 40 and 50 on a Shore D scale. In another example embodiment, the rigid plastic comprises polypropylene and the flexing agent comprises a propylene-based elastomer. In yet another example embodiment, the body region  30  formed from only rigid plastic consisting of polypropylene and the flexing agent consisting of a propylene-based elastomer. 
     What have been described above are examples of the present invention. It is, of course, not possible to describe every conceivable combination of components or methodologies for purposes of describing the present invention, but one of ordinary skill in the art will recognize that many further combinations and permutations of the present invention are possible. Accordingly, the present invention is intended to embrace all such alterations, modifications and variations that fall within the spirit and scope of the appended claims.