A roll straightening machine for straightening an elongated string member includes at least one first straightening roll rotatably mounted around a first rotation axis, and at least one second straightening roll rotatably mounted around a second rotation axis. The first and second rotation axis and rolls are oblique with respect to a longitudinal axis of an elongated string member to be received in the roll straightening machine, and also oblique with respect to one another. In order to provide a roll straightening machine that can be set up flexibly for different requirement profiles, the first rotation axis is mounted on a first holding device and the second rotation axis is mounted on a second holding device. The first and the second holding devices are supported by a frame in a removable manner, which is arranged to receive a variable number of holding devices having the straightening rolls.

A pipe straightening apparatus comprising a first set of rotatably mounted elements which define, at least in part, a first passageway through which a pipe can be constrained to pass, so as to straighten the pipe, wherein the first set of rotatably mounted elements are arranged such that when a pipe translates within the first passageway, relative to the apparatus, the first set of rotatably mounted elements roll along the pipe, relative to the pipe, in a direction which has a component in the circumferential direction of the pipe and a second set of rotatably mounted elements which define, at least in part, a second passageway through which a pipe can pass, wherein the second set of rotatably mounted elements are arranged such that when a pipe translates within the second passageway, relative to the apparatus, the second set of rotatably mounted elements roll along the pipe, relative to the pipe, in a direction that is substantially parallel to the longitudinal axis of the pipe.

A pipe straightening apparatus comprising a first set of rotatably mounted elements which define, at least in part, a first passageway through which a pipe can be constrained to pass, so as to straighten the pipe, wherein the first set of rotatably mounted elements are arranged such that when a pipe translates within the first passageway, relative to the apparatus, the first set of rotatably mounted elements roll along the pipe, relative to the pipe, in a direction which has a component in the circumferential direction of the pipe and a second set of rotatably mounted elements which define, at least in part, a second passageway through which a pipe can pass, wherein the second set of rotatably mounted elements are arranged such that when a pipe translates within the second passageway, relative to the apparatus, the second set of rotatably mounted elements roll along the pipe, relative to the pipe, in a direction that is substantially parallel to the longitudinal axis of the pipe.