Coupling and Seal

Abstract

A mechanical coupling for joining pipe elements end to end has a channel that receives a ring seal. The channel is defined by oppositely disposed side surfaces and the ring seal has lobes on opposite sides. The lobes have surfaces facing the side surfaces of the channel. When the ring seal is seated within the channel, each lobe surface contacts a respective side surface such that the lobes deform inwardly toward the center of the channel.

What is claimed is: 
     
         1 . A coupling for joining pipe elements in end to end relation, said coupling comprising:
 a plurality of segments attached to one another end to end and surrounding a central space, each of said segments having a channel extending circumferentially around and facing said central space, each of said channels being defined by first and second side surfaces located on opposite sides of said segments and a back surface extending between said side surfaces;   a seal positioned within said central space, said seal comprising a ring having first and second lobes positioned on opposite sides thereof, said first lobe having a first lobe surface facing toward said first side surface and said second lobe having a second lobe surface facing toward said second side surface, said first lobe surface being oriented angularly with respect to said first side surface, and said second lobe surface being oriented angularly with respect to said second side surface when said seal is in an undeformed shape; wherein   when said first and second lobes are engaged with said pipe elements, at least a portion of said first and second lobe surfaces are in contact with said side surfaces such that said lobes will deform toward a center of said channel when said ring is seated within said channel; and   a connection member positioned at one end of each of said segments, said connection members on said segments being adjustably tightenable for drawing said segments toward one another and seating said ring within said channel, thereby deforming said seal.   
     
     
         2 . A coupling for joining pipe elements in end to end relation, said coupling comprising:
 a plurality of segments attached to one another end to end and surrounding a central space, each of said segments having a channel extending circumferentially around and facing said central space, each of said channels being defined by first and second side surfaces located on opposite sides of said segments and a back surface extending between said side surfaces;   a seal positioned within said central space, said seal comprising a ring having at least one lobe positioned on a side thereof, said at least one lobe having a lobe surface facing toward said first side surface, said lobe surface being oriented angularly with respect to said first side surface when said seal in in an undeformed shape; wherein   when said at least one lobe is engaged with said pipe element, at least a portion of said lobe surface is in contact with said first side surface such that said at least one lobe will deform toward a center of said channel when said ring is seated within said channel; and   connection members being positioned at opposite ends of each of said segments, said connection members being adjustably tightenable for drawing said segments toward one another and seating said ring within said channel, thereby deforming said at least one lobe.   
     
     
         3 . A coupling for joining pipe elements in end to end relation, said coupling comprising:
 a plurality of segments attached to one another end to end and surrounding a central space, each of said segments having a channel extending circumferentially around and facing said central space, each of said channels being defined by first and second side surfaces located on opposite sides of said segments and a back surface extending between said side surfaces;   a seal positioned within said central space, said seal comprising a ring having first and second lobes positioned on opposite sides thereof, said first lobe having a first lobe surface facing toward said first side surface and said second lobe having a second lobe surface facing toward said second side surface; wherein   when said first and second lobes are engaged with said pipe elements said seal is in an undeformed state, at least a portion of said first and second lobe surfaces being wider than the widest distance between said first and second side surfaces such that said lobes will deform toward a center of said channel when said ring is seated within said channel; and   connection members being positioned at opposite ends of each of said segments, said connection members being adjustably tightenable for drawing said segments toward one another and seating said ring within said channel, thereby deforming said lobes.   
     
     
         4 . The coupling according to  claim 3 , wherein said first lobe surface is oriented angularly with respect to said first side surface and said second lobe surface is oriented angularly with respect to said second side surface when said seal is in said undeformed shape. 
     
     
         5 . The coupling according to  claim 3 , wherein said first and second lobe surfaces comprises convexly curved surfaces when said seal is in said undeformed shape. 
     
     
         6 . The coupling according to  claim 5 , wherein said first and second side surfaces comprise convexly curved surfaces. 
     
     
         7 . The coupling according to  claim 3 , wherein said first and second side surfaces comprise convexly curved surfaces. 
     
     
         8 . A coupling for joining pipe elements in end to end relation, said coupling comprising:
 a plurality of segments attached to one another end to end and surrounding a central space, each of said segments having a channel extending circumferentially around and facing said central space, each of said channels being defined by first and second side surfaces located on opposite sides of said segments and a back surface extending between said side surfaces;   a seal positioned within said central space, said seal comprising a ring having first and second lobes positioned on opposite sides thereof, said first lobe having a first lobe surface facing toward said first side surface and said second lobe having a second lobe surface facing toward said second side surface;   a first gland attached to said first lobe and a second gland attached to said second lobe, said first and second glands extending circumferentially about said ring, said first gland having a first sealing surface, said second gland having a second sealing surface, said first and second sealing surfaces facing said central space; wherein   when said sealing surfaces are engaged with said pipe element, said first lobe surface is oriented angularly with respect to said first side surface and said second lobe surface is oriented angularly with respect to said second side surface such that said lobes will deform toward a center of said channel when said ring is seated within said channel; and   connection members being positioned at opposite ends of each of said segments, said connection members being adjustably tightenable for drawing said segments toward one another and seating said ring within said channel, thereby deforming said lobes.   
     
     
         9 . The coupling according to  claim 8 , wherein said connection members on each of said segments comprise a pair of projections, one said projection being positioned on each of said opposite ends of said segments, said projections having holes to receive a fastener, said fastener being adjustably tightenable. 
     
     
         10 . The coupling according to  claim 8 , wherein said coupling comprises two of said segments. 
     
     
         11 . The coupling according to  claim 8 , wherein said first lobe surface has an orientation angle relative to said first side surface from 1° to 20°. 
     
     
         12 . The coupling according to  claim 11 , wherein said orientation angle of said first lobe surface is 8°. 
     
     
         13 . The coupling according to  claim 11 , wherein said second lobe surface has an orientation angle relative to said second side surface from 1° to 20°. 
     
     
         14 . The coupling according to  claim 13 , wherein said orientation angle of said second lobe surface is 8°. 
     
     
         15 . The coupling according to  claim 8 , wherein said second lobe surface has an orientation angle relative to said second side surface from 1° to 20°. 
     
     
         16 . The coupling according to  claim 15 , wherein said orientation angle of said second lobe surface is 8°. 
     
     
         17 . The coupling according to  claim 8 , wherein said seal is formed of a rubber material. 
     
     
         18 . The coupling according to  claim 8 , wherein said seal is formed of a material having low elasticity. 
     
     
         19 . The coupling according to  claim 18 , wherein said seal is formed of a material having an elastic limit from 0.05% to 20%. 
     
     
         20 . The coupling according to  claim 18 , wherein said seal is formed of a material having an elastic limit from 0.5% to 10%. 
     
     
         21 . The coupling according to  claim 18 , wherein said seal is formed of a material having an elastic limit from 1% to 5%. 
     
     
         22 . The coupling according to  claim 18 , wherein said material having low elasticity is selected from the group consisting of thermoplastic resins, thermosets, epoxies and composites including polyethylene, polypropylene, polyamides, polyvinyl chloride, polycarbonate, polystyrene, acetals, acrylics, fluoropolymers and combinations thereof. 
     
     
         23 . The coupling according to  claim 8 , wherein each of said segments further comprises first and second keys positioned on opposite sides of said segments, each of said keys extending circumferentially around and projecting toward an axis extending through said central space. 
     
     
         24 . The coupling according to  claim 23 , wherein said first keys on each of said segments are positioned in spaced relation to said first side surfaces of said segments. 
     
     
         25 . The coupling according to  claim 24 , wherein said second keys on each of said segments are positioned in spaced relation to said second side surfaces of said segments. 
     
     
         26 . The coupling according to  claim 23 , wherein each of said keys comprises an arcuate surface facing said axis. 
     
     
         27 . The coupling according to  claim 8 , further comprising:
 a first spring element positioned on said first gland opposite to said first sealing surface;   a second spring element positioned on said second gland opposite to said second sealing surface, said spring elements extending circumferentially around said ring and biasing said first and second sealing surfaces toward said central space.   
     
     
         28 . In combination, first and second pipe elements and a coupling for joining said pipe elements in end to end relation, said coupling comprising:
 a plurality of segments attached to one another end to end and surrounding a central space, said pipe elements being received within said central space, each of said segments having a channel extending circumferentially around and facing said central space, each of said channels being defined by first and second side surfaces located on opposite sides of said segments and a back surface extending between said side surfaces;   a seal positioned within said central space, said seal comprising a ring surrounding said pipe elements, said ring having first and second lobes positioned on opposite sides thereof, said first lobe having a first lobe surface facing toward said first side surface and said second lobe having a second lobe surface facing toward said second side surface;   a first gland attached to said first lobe and a second gland attached to said second lobe, said first and second glands extending circumferentially about said ring, said first gland having a first sealing surface, said second gland having a second sealing surface, said first and second sealing surfaces facing said central space; wherein   when said sealing surfaces are engaged with said pipe element, said first lobe surface is oriented angularly with respect to said first side surface and said second lobe surface is oriented angularly with respect to said second side surface such that said lobes will deform toward a center of said channel when said ring is seated within said channel; and   connection members being positioned at opposite ends of each of said segments, said connection members being adjustably tightenable for drawing said segments toward one another and seating said ring within said channel, thereby deforming said lobes.   
     
     
         29 . The combination according to  claim 28 , wherein said connection members on each of said segments comprise a pair of projections, one said projection being positioned on each of said opposite ends of said segments, said projections having holes to receive a fastener, said fastener being adjustably tightenable. 
     
     
         30 . The combination according to  claim 28 , wherein said coupling comprises two of said segments. 
     
     
         31 . The combination according to  claim 28 , wherein said first lobe surface has an orientation angle relative to said first side surface from 1° to 20°. 
     
     
         32 . The combination according to  claim 31 , wherein said orientation angle of said first lobe surface is 8°. 
     
     
         33 . The combination according to  claim 31 , wherein said second lobe surface has an orientation angle relative to said second side surface from 1° to 20°. 
     
     
         34 . The combination according to  claim 33 , wherein said orientation angle of said second lobe surface is 8°. 
     
     
         35 . The combination according to  claim 28 , wherein said second lobe surface has an orientation angle relative to said second side surface from 1° to 20°. 
     
     
         36 . The combination according to  claim 35 , wherein said orientation angle of said second lobe surface is 8°. 
     
     
         37 . The combination according to  claim 28 , wherein said seal is formed of a rubber material. 
     
     
         38 . The combination according to  claim 28 , wherein said seal is formed of a material having low elasticity. 
     
     
         39 . The combination according to  claim 38 , wherein said seal is formed of a material having an elastic limit from 0.05% to 20%. 
     
     
         40 . The combination according to  claim 38 , wherein said seal is formed of a material having an elastic limit from 0.5% to 10%. 
     
     
         41 . The combination according to  claim 38 , wherein said seal is formed of a material having an elastic limit from 1% to 5%. 
     
     
         42 . The combination according to  claim 38 , wherein said material having low elasticity is selected from the group consisting of thermoplastic resins, thermosets, epoxies and composites including but not limited to polyethylene, polypropylene, polyamides, polyvinyl chloride, polycarbonate, polystyrene, acetals, acrylics, fluoropolymers and combinations thereof. 
     
     
         43 . The combination according to  claim 28 , wherein each of said segments further comprises first and second keys positioned on opposite sides of said segments, each of said keys extending circumferentially around and projecting toward an axis extending through said central space. 
     
     
         44 . The combination according to  claim 43 , wherein said first keys on each of said segments are positioned in spaced relation to said first side surfaces of said segments. 
     
     
         45 . The combination according to  claim 44 , wherein said second keys on each of said segments are positioned in spaced relation to said second side surfaces of said segments. 
     
     
         46 . The combination according to  claim 43 , wherein each of said keys comprises an arcuate surface facing said axis. 
     
     
         47 . The combination according to  claim 43 , wherein each of said pipe elements comprises a respective circumferential groove positioned proximate to an end of each of said pipe elements, said keys engaging said grooves upon adjustable tightening of said connection members. 
     
     
         48 . The combination according to  claim 28 , further comprising a first gland attached to said first lobe and a second gland attached to said second lobe, said first and second glands extending circumferentially about said ring, said first gland having a first sealing surface facing said central space, said second gland having a second sealing surface facing said central space, said sealing surfaces defining an inner diameter substantially equal to an outer diameter of said pipe elements. 
     
     
         49 . The combination according to  claim 48 , further comprising:
 a first spring element positioned on said first gland opposite to said first sealing surface;   a second spring element positioned on said second gland opposite to said second sealing surface, said spring elements extending circumferentially around said ring and biasing said first and second sealing surfaces toward said pipe elements.   
     
     
         50 . The combination according to  claim 28 , further comprising a first gland attached to said first lobe and a second gland attached to said second lobe, said first and second glands extending circumferentially about said ring, said first gland having a first sealing surface facing said central space, said second gland having a second sealing surface facing said central space, said sealing surfaces defining an inner diameter greater than an outer diameter of said pipe elements when said seal is in said undeformed state. 
     
     
         51 . The combination according to  claim 50 , wherein said inner diameter defined by said sealing surfaces exceeds said outer diameter of said pipe elements from 0.001 inches to 0.3 inches when said seal is in said undeformed shape. 
     
     
         52 . The combination according to  claim 50 , wherein said inner diameter defined by said sealing surfaces exceeds said outer diameter of said pipe elements by 0.05 inches when said seal is in said undeformed shape. 
     
     
         53 . The combination according to  claim 50 , further comprising:
 a first spring element positioned on said first gland opposite to said first sealing surface;   a second spring element positioned on said second gland opposite to said second sealing surface, said spring elements extending circumferentially around said ring and biasing said first and second sealing surfaces toward said pipe elements.   
     
     
         54 . A method of joining first and second pipe elements together in end to end relation, said method comprising:
 supporting at least first and second segments in spaced apart relation to one another on a seal comprising a ring located in a central space surrounded by said segments, said at least first and second segments being attached to one another end to end, each of said at least first and second segments having a circumferential channel, said ring being received within said circumferential channels, said ring having first and second circumferential lobes on opposite sides thereof, said first and second circumferential lobes having respective first and second lobe surfaces respectively facing first and second side surfaces defining said circumferential channel, said first lobe surface being angularly oriented with respect to said first side surface, said second lobe surface being angularly oriented with respect to said second side surface;   inserting said first and second pipe elements axially into said central space and engaging said first and second pipe elements respectively with said first and second circumferential lobes on opposite sides of said ring while maintaining said first lobe surface angularly oriented with respect to said first side surface and said second lobe surface angularly oriented with respect to said second side surface;   drawing said at least first and second segments toward said central space, thereby deforming said ring so as to substantially align said first lobe surface with said first side surface and to substantially align said second lobe surface with said second side surface.   
     
     
         55 . The method according to  claim 54 , wherein said at least first and second segments each comprises first and second keys positioned on opposite sides of said segments, each of said keys extending circumferentially around and projecting toward said pipe elements, said method further comprising engaging said keys with said pipe elements upon said drawing said at least first and second segments toward one another. 
     
     
         56 . The method according to  claim 55 , further comprising engaging said keys within circumferential grooves located in said first and second pipe elements. 
     
     
         57 . A method of joining first and second pipe elements together in end to end relation, said method comprising:
 inserting said first and second pipe elements into a central space surrounded by a seal comprising a ring having first and second circumferential lobes on opposite sides thereof;   surrounding said ring by at least a first and a second segment of a coupling, each of said segments having a circumferential channel, said ring being received within said circumferential channels, said first and second lobes having respective first and second lobe surfaces respectively facing first and second side surfaces defining said circumferential channel, said first lobe surface being angularly oriented with respect to said first side surface and said second lobe surface being angularly oriented with respect to said second side surface while said first and second pipe elements are engaged with said first and second circumferential lobes;   drawing said at least first and second segments toward one another, thereby deforming said ring so as to substantially align said first lobe surface with said first side surface and to substantially align said second lobe surface with said second side surface.   
     
     
         58 . The method according to  claim 57 , wherein said at least first and second segments each comprises first and second keys positioned on opposite sides of said segments, each of said keys extending circumferentially around and projecting toward said pipe elements, said method further comprising engaging said keys with said pipe elements upon said drawing said at least first and second segments toward one another. 
     
     
         59 . The method according to  claim 58 , further comprising engaging said keys within circumferential grooves located in said first and second pipe elements.