Patent ID: 7219527

Claim:
A mandrel for bending a pipe, the mandrel comprising: a plurality of plugs with each of the plurality of plugs being in the form of a disc provided with a through-hole substantially in the center thereof, and a flexible member being inserted through the through-holes of the plurality of plugs, and one end of the flexible member being secured to a shank so that the plurality of plugs are connected in series to the shank, wherein each of the plurality of plug is provided with a slant surface which descends from about a center of the plug toward an outer periphery of the plug so that a peripheral portion of the plug becomes thinner than a central portion of the plug; and a turn lock mechanism for restricting rotation of each of the plurality of plugs, the turn lock mechanism comprises a flexible turn lock member which passes through a lock hole provided in each of the plurality of plugs and arranged parallel to the through hole, and the turn lock member is secured to the shank at one end.