Cold expansion pipe fitting, pipe connection, system, equipment, and method

A pipe fitting for forming a cold expansion pipe connection, comprising:

• a tubular connecting part extending substantially in an axial direction and a shoulder extending radially outwards from one end of the tubular connecting part;
• the tubular connecting part being configured to be inserted into a pipe end section of a pipe expanded by an expanding tool head comprising a plurality of radially movable outer spreading surfaces, the outer spreading surfaces comprising a first circumferential groove crossing each of the outer spreading surfaces and leaving, during expansion of the pipe end section, a first circumferential intact sealing region on an inner surface of the pipe end section at a first distance from an end of the pipe;
• the tubular connecting part comprising a first radially outwards extending circumferential sealing barb positioned for engaging, when in use, with the first circumferential intact sealing region during shrinkage of the pipe end section for forming a sealing between the pipe fitting and the pipe;
• wherein the sealing barb has a wedge-shape longitudinal section in the axial direction with a first facet with a first slope on a side of a free end of the tubular connecting part, and a second facet with a second slope steeper than the first slope on a side of the shoulder, the first and the second facets being connected via a tip, wherein the tip has a radius of curvature r in the range of 0.005 to 0.020 inches, and wherein the first slope lies at an angle of 20 to 25 degrees with respect to the axial direction of the tubular connecting part and extends to the tip connecting the first and the second facets.