System having a device for producing a pipeline unit and method for producing a pipeline unit

A system having a device for producing a pipeline unit from a pipeline having a pipeline outer surface and a pipe connector having a pipe connector outer surface, wherein the device comprises an annularly structured stress-relieving device having a longitudinal central axis and a radially inwardly pointing stress-relieving device inner surface, wherein the stress-relieving device inner surface is adapted to the pipeline outer surface and/or the pipe connector outer surface in order to at least partially receive the pipeline unit to be produced in an operating state, and the stress-relieving device surrounds a pressure tool in the operating state so as to support the pipeline unit to be produced in the operating state when the pipeline is expanded by the pressure tool,

• wherein the stress-relieving device has a stress-relieving device annular body, which has two annular body elements that together form the stress-relieving device inner surface, which elements respectively have a first end section and a second end section, wherein the first end sections are arranged pivotally moveable with respect to one another about a pivot axis,
• wherein a connection element is arranged on each second end section and the connection elements are configured to interact with one another in order to releasably connect the second end sections,
• wherein the stress-relieving device inner surface has at least one annular groove for at least partially receiving the pipe connector,
• wherein the stress-relieving device forms an annular projection projecting radially inwards, which is delimited on one side by a first axial stress-relieving device end face and on the other side by a lateral groove boundary surface of the at least one annular groove facing away from the first axial stress-relieving device end face,
• wherein the stress-relieving device has a second axial stress-relieving device end face opposite the first axial stress-relieving device end face, which is stepped, which forms an annular stress-relieving device collar radially supporting the pipeline inserted into the pipe connector,
• wherein the annular projection projecting radially inwards projects radially inwards to such an extent that the annular projection forms a stop for abutting a longitudinal outermost end face of the pipeline inserted into the pipe connector.