Pipe element having shoulder, groove and bead and methods and apparatus for manufacture thereof

In combination, a coupling and at least one pipe element, said pipe element having an outer diameter and at least one end, wherein:

• said pipe element comprises:
• a shoulder positioned at said at least one end, said shoulder extending circumferentially around said pipe element and having an outwardly facing surface, said outwardly facing surface having an outer diameter greater than said outer diameter of said pipe element excluding said shoulder;
• a groove positioned adjacent to said shoulder, said groove extending circumferentially around said pipe element, said groove being defined by a first side surface positioned contiguous with said shoulder, a second side surface positioned in spaced apart relation to said first side surface, and a floor surface extending between said first and second side surfaces, said floor surface having an outer diameter less than said outer diameter of said pipe element excluding said groove;
• said first side surface being oriented substantially perpendicularly to a longitudinal axis of said pipe element;
• and wherein
• said coupling comprises:
• a plurality of segments attached to one another end to end surrounding a central space, each of said segments having an arcuate surface received within said groove, said arcuate surfaces of each of said segments comprising:
• a first lateral surface in facing relation with said first side surface of said groove;
• a second lateral surface in facing relation with said second side surface of said groove;
• a radial surface in facing relation with said floor surface of said groove;
• and wherein
• said pipe element further comprises a bead positioned contiguous with said groove, said bead extending circumferentially around and projecting radially outwardly from said pipe element and having an apex with an outer diameter greater than said outer diameter of said pipe element excluding said bead.