Patent ID: 7975956

Claim:
A coiler mandrel, comprising: a cylindrical body having a peripheral outer surface and guide grooves arranged axially in the outer surface; and radially displaceable expansion segments, each of the expansion segments having an outer member that is curved to correspond to and project over a portion of the outer surface of the cylindrical body, and a web that projects radially inwardly from the outer member, each web being displaceably arranged in a respective one of the guide grooves so that each of the outer members covers a portion of the outer surface of the cylindrical body and so that the expansion segments are radially displaceable, wherein at least one sidewall ( 7 ) of the guide groove ( 12 ) or at least one sidewall of the web is designed with an axial bore ( 8 ) or a groove, wherein the bore is open toward the guide groove, a clamping jaw being arranged in the axial bore ( 8 ) so as to be movable perpendicular to a radius of the cylindrical body, and a hose is inserted in the axial bore or groove in the sidewall of the guide groove or of the web, the hose being expandable under pressure so as to push the clamping jaw against the web to exert a clamping force on the web.