Coupling having angularly oriented shoulder surfaces

A coupling for joining pipe elements together in end to end relation, said coupling comprising:

• a plurality of segments attached to one another end to end surrounding a central space, each said segment having a cavity therein, each said cavity facing said central space and extending lengthwise along each said segment;
• each said segment further comprising a pair of arcuate keys extending lengthwise along each said segment and projecting inwardly toward said central space, said arcuate keys being positioned in spaced relation to one another on opposite sides of said cavity;
• each said segment further comprising a pair of first arcuate shoulder surfaces extending circumferentially along the length of each said segment and facing said central space, said first arcuate shoulder surfaces being positioned in spaced relation to one another on opposite sides of said cavity, each said first arcuate shoulder surface being positioned contiguous with said cavity and between a respective one of said keys and said cavity, said first arcuate shoulder surfaces being angularly oriented with respect to an axis oriented perpendicularly to a plane containing said segments, said first arcuate shoulder surfaces being engageable with an outer surface of said pipe elements when said pipe elements are positioned within said central space.

A coupling for joining pipe elements together in end to end relation, said coupling comprising:

• a plurality of segments attached to one another end to end surrounding a central space, at least one of said segments having a cavity therein, said cavity facing said central space and extending lengthwise along said one segment;
• said one segment further comprising an arcuate key extending lengthwise along said one segment, said arcuate key being positioned in spaced relation to said cavity and projecting inwardly toward said central space;
• said one segment further comprising an arcuate shoulder surface extending circumferentially along the length of said one segment, said arcuate shoulder surface facing said central space and being positioned contiguous with said cavity and between said cavity and said arcuate key, said arcuate shoulder surface having a first boundary adjacent to said key and a second boundary adjacent to said cavity, said first boundary having a first radius of curvature, said second boundary having a second radius of curvature, said first radius of curvature being different from said second radius of curvature.

A method of joining pipe elements in end to end relationship using a coupling formed of a plurality of segments connected end to end by a plurality of adjustably tightenable fasteners, said segments being connected to one another in spaced apart relation, said segments surrounding a central space, at least one of said segments having a cavity therein, said cavity facing said central space and extending lengthwise along said one segment, said one segment further comprising an arcuate key extending lengthwise along said one segment, said arcuate key being positioned in spaced relation to said cavity and projecting inwardly toward said central space, said one segment further comprising an arcuate shoulder surface extending circumferentially along the length of said one segment, said arcuate shoulder surface facing said central space and being positioned contiguous with said cavity and between said cavity and said arcuate key, said arcuate shoulder surface being angularly oriented with respect to an axis oriented perpendicularly to a plane containing said segments, said method comprising:

• inserting said pipe elements into said central space from opposite sides of said coupling;
• tightening said fasteners so as to draw said segments toward one another and thereby engaging said arcuate shoulder surface with an outer surface of at least one of said pipe elements.