810 Каталог GUHRING 2016 Режущий инструмент для обработки наружной и внутренней резьбы Стр.798

Каталог GUHRING 2016 Режущий инструмент для резьбы Стр. 798 0810 Lab2u

Technical section GENERAL INFORMATION THREAD FORMING Tapping size hole diameter With fluteless tapping, the tapping size hole diameter influences the distinction of the formed thread. A too small tapping size hole diameter results in an over-forming of the thread which must definitely be prevented because this can lead to tool breakage. A too large tapping size hole is acceptable with certain tolerances because formed threads have a sufficient loading capacity from a 50% bearing depth. The thread M18x1.5 mm example clearly shows the influence of the tapping size hole diameter selection: M 18 x 1.00 17.55 17.52 17.62 16.917 17.217 M 18 x 1.50 17.30 17.26 17.38 16.376 16.751 M 18 x 2.00 17.10 17.05 17.20 15.835 16.310 Pre-drilling 0 17.4 mm PHPI Tapping size hole diameter is too small: thread over-formed no form pocket (claw) profile too high Optimal tapping size hole diameter: thread fully formed small form pocket (claw) optimal height of profile Tapping size hole diameter is too large: thread not formed large form pocket (claw) height of profile too low min. max. Tapping size hole diameter tolerance zone to DIN 13, part 50 Influence of the tapping size hole on tool life, torque and process reliability The optimisation of the pre-drilling diameter is k especially worthwhile in mass production. The larger it is, the longer the tool life and the less the required torque is. The graphic clearly shows the relationship 798 GUHRING