Gate shapes on the tap
An important parameter for the function and the application range of the tool is the gate on the tap. Since the thread quality and last but not least the tool life are influenced by the gate shape, its selection should be made carefully. In general, the following five standardized gate shapes are distinguished:
Gate form A according to DIN 2197
- straight grooves
- for short through holes
Gate form B according to DIN 2197
- straight grooves with peel cut
- for medium through holes in long cutting materials
Gate form C according to DIN 2197
- straight grooves or spiral grooves
- for blind and through holes in short chipping materials
Gate shape D according to DIN 2197
- straight grooves or spiral grooves
- for blind and through holes with long thread runout
Gate form E according to DIN 2197
- straight grooves or spiral grooves
- for blind holes with extremely short thread runout