Thread rolling tool

Abstract

The invention relates to a thread rolling tool for rolling and/or repairing a thread, comprising a clamping device to be fastened to a pipe end, and at least one profiled roll for rolling a thread into the pipe end or repairing a thread at the pipe end. According to the invention, the at least one profiled roll tapers in a direction in which the profiled roll advances such that a tapered, in particular a conical, thread can be rolled into the pipe end.

1 . Thread-rolling tool for rolling and/or repairing a thread, with
 a) a clamping jig ( 12 ) for fastening to a pipe end ( 18 ) and   b) at least one profile roll ( 14 . 1 ) for rolling a thread into the pipe end ( 18 ) or for repairing a thread at the pipe end ( 18 ),   wherein   c) the at least one profile roll ( 14 . 1 ) tapers in a feed direction of the profile roll ( 14 ), so that a tapering, especially a conical thread can be rolled into the pipe end ( 18 ).   
     
     
         2 . Thread-rolling tool according to  claim 1 , wherein the profile roll ( 14 ) is pitchless. 
     
     
         3 . Thread-rolling tool according to  claim 1 , comprising
 a roll holder ( 16 ),
 on which the at least one profile roll ( 14 . 1 ) is fastened and 
 by means of which the at least one profile roll ( 14 . 1 ) can be so guided helically around the pipe end ( 18 ) that the at least one profile roll ( 14 . 1 ) rolls a thread into the pipe end ( 18 ). 
   
     
     
         4 . Thread-rolling tool according to  claim 1 , wherein
 the roll holder ( 16 ) is coupled by means of a thread ( 26 ) with the clamping jig ( 12 ), so that a rotation of the roll holder ( 16 ) around a pipe longitudinal axis (L) of the pipe end ( 18 ) leads to an axial movement of the roll holder ( 16 ) along the pipe longitudinal axis (L).   
     
     
         5 . Thread-rolling tool according to  claim 1 , comprising at least one second profile roll ( 14 . 2 ), which is so fastened to the roll holder ( 16 ) that
 the second profile roll ( 14 . 2 ), during rotation of the roll holder ( 16 ) around the pipe longitudinal axis (L), rolls at least partly in grooves rolled by the first profile roll ( 14 . 1 ) and wherein,   in operation, it generates, in a direction at least partly opposed to a first passive force that acts on the first profile roll ( 14 . 1 ), a second passive force.   
     
     
         6 . Thread-rolling tool according to  claim 5 , wherein
 the first profile roll ( 14 . 1 ) is mounted to rotate around a first profile roll axis of rotation (D 14.1 ) and a first offset angle between the first profile roll axis of rotation (D 14.1 ) and the pipe longitudinal axis amounts to at most 2°, especially at most 1° and/or   the second profile roll ( 14 . 2 ) is mounted to rotate around a second profile roll axis of rotation (D 14.1 ) and a second offset angle between the second profile roll axis of rotation (D 14.2 ) and the pipe longitudinal axis amounts to at most 2°, especially at most 1°.   
     
     
         7 . Thread-rolling tool according to  claim 5 , comprising at least one third profile roll ( 14 . 3 ), which is so fastened to the roll holder ( 16 ) wherein
 the third profile roll ( 14 . 3 ), during rotation of the roll holder ( 16 ) around the pipe longitudinal axis (L), rolls at least partly in the grooves rolled by the first profile roll ( 14 . 1 ) and/or the second profile roll ( 14 . 2 ) and wherein,   in operation, it generates a third passive force, which together with the first passive force and the second passive force preferably adds up vectorially to zero.   
     
     
         8 . Thread-rolling tool according to  claim 7 , wherein
 the third profile roll ( 14 . 3 ) is mounted to rotate around a third profile roll axis of rotation and   the third profile roll ( 14 . 3 ) is mounted to rotate around a third profile roll axis of rotation (D 14.3 ) and a third offset angle between the third profile roll axis of rotation (D 14.3 ) and the pipe longitudinal axis amounts to at most 2°, especially at most 1°.   
     
     
         9 . Method for producing or repairing a conical thread, with the steps of:
 (i) fastening a thread-rolling tool ( 10 ) according to  claim 1  onto a pipe end ( 18 ) by means of the clamping jig ( 12 ) and   (ii) rotating the roll holder ( 16 ), wherein the thread moves the roll holder ( 16 ) axially along a pipe longitudinal axis (L) of the pipe end ( 18 ), so that the at least one profile roll ( 14 ) moves helically around the pipe longitudinal axis (L) and rolls a conical thread into the pipe end ( 18 ).   
     
     
         10 . Method according to  claim 9 , wherein a thread is rolled with a thread width that corresponds at most to a profile roll width (B 14 ) of a profiled shell surface of the profile roll ( 14 ).