METHOD OF FORMING SCREW THREAD AND TUBULAR BODY WITH SCREW THREAD FORMED BY SAID METHOD

摘要

The production of the internal thread of a connection sleeve (4), which is used as a coupling element for parts of a rock support or of a drill rod, by machine-forming, in particular by thread-cutting, entails great effort since, in the round thread used here, a considerable amount of machining work is required. Furthermore, it is disadvantageous in this application in the machining of the thread that the long-term strength of the connection sleeve is considerably impaired due to the notch effect in the base region of the thread turns. A connection sleeve and a method for its production are proposed, in which the internal thread is produced without machining by shaping the outside of the connection sleeve (4) in the manner of a thread so that the image of this shaping forms the internal thread to be produced on the inside. Apart from the increase in strength caused by the non-cutting shaping, which is usually cold shaping, due to material reinforcement, the further advantage results that the shaping required here can be applied in a single operation so that the production costs of connection sleeves (4) of this type can be reduced. Furthermore, it is advantageous that the external thread, interacting with the internal thread of the connection sleeve, of the components to be connected to one another can have a basic shape which corresponds to the outside thread-type shaping of the connection sleeve (4). IMAGE