Undoubtedly the threaded, spline, and formed profiles by rolling system offers many advantages compared to conventional systems of threading (cutting system). Economy, resistance, precision, perfect surface finish and unimaginable productions are some of the advantages that characterize this production system.
The feasibility of this process depends mainly on four factors: the material to be rolled, the profile to be rolled, the machine and the tool to be used.
Preparation of the parts to be threaded
It is very important a good preparation of the parts to be threaded, knurled or grooved, in order to guarantee a correct use of the tool and its longer useful life. The three key points are:
- Bevels: with an angle of 22º 30′ +/-2º
- Pre-rolling diameter: The one that corresponds to the piece to be rolled.
- Hardness of the piece: homogeneity in the hardness of the pieces to be laminated and hardness not higher than 30-23 HRc, always depending on the profile to be made.
If the material is very hard, it is necessary that the bevels be 15º instead of 22º. For the pre-rolling diameters of the pieces cannot prescribe absolute values but for information purposes we can quote the following formula.
Calculation of pre-rolling diameters
You can see our tables to get more information. Download pdf.