Furrows
The furrow is a manufacturing process from the group of pressing in that the pressure forming counts.
When furrowing, a pointed or wedge-shaped tool is pulled over the surface of the workpiece, pressure forces pressing the tool against the surface at the same time, so that a furrow is formed. It is used for scribing , i.e. to make markings on workpieces, and for lettering. It is mainly used in handicrafts; it is hardly used industrially. Tools include drawing pins . Because of the friction between the workpiece and the tool, they have to be very wear-resistant and therefore usually consist of hardened tool steel , hard metal or diamond , some with exchangeable tips.
Threads can also be created by grooving:
- Wood screws (partly outdated) and universal screws are grooved in wood, wood-based material (both often pre-drilled) or plastic dowels.
- Self-tapping screws form their thread seat in drilled sheet metal (metal).
- Very similarly shaped screws, but with lower strength requirements, form threads in cylindrical or (3 or 4-sided) prismatic holes - typical for connecting parts of plastic housings.
- Special thread formers produce metric internal threads in metal in bores.
- External threads of various screws made of metal can also be formed by grooves.
See also
- Center punching - related method of scribing
literature
- Raphael Petry: Impressions in: Hartmut Hoffmann , Reimund Neugebauer , Günter Spur : Handbuch Umformen , Hanser, 2012, p. 312 f.