798 Каталог GUHRING 2016 Режущий инструмент для обработки наружной и внутренней резьбы Стр.786

Каталог GUHRING 2016 Режущий инструмент для резьбы Стр. 786 0798 Lab2u

Technical section GENERAL INFORMATION FOR TAPPING Chamfer forms, selection and application Chamfer lead length Chamfer lead length for sets of 3 taps for sets of 2 taps Form A - approx. 6 threads first tap nimiiniiiiELJ ( Form D approx. 4 threads second tap WMWA r- , ITT wiiMMiHn WvWANV-1 Form D - approx. 5 threads first tap rVVVVVVW A. i Tlllllllllllllllllllg Form C 1 approx. 2 threads bottoming tap niiiiiiiiiiiiiiiiiuirM ( -1 r _ i annmv 0 thrnoHc Form c - bottoming tap HlEllEllQ Application recommendations While in the first instance, the type of tapped hole required determines the chamfer, generally the tap geometry - i.e. form, number and direction of flutes, cutting angle, etc. - depend on the material to be machined and on the application. Basically, taps up to M16 for tapping ISO metric threads or for the engineering industry in general, have 3 flutes, and above this size 4 or more flutes. Taps with left-hand flutes and taps with spiral points remove the chips in the cutting direction or direction of feed and are therefore especially suitable for tapping through holes. Taps with straight flutes and long chamfer lead (form D) also give good results. As far as blind holes are concerned we recommend taps with right-hand spiral flutes or straight fluted taps with a short chamfer lead length. Tools with right-hand spiral flutes have the chip flow in the backward direction, i.e. up the flutes. The chamfer lead length is designed in such a way so that during the return movement chips do not jam and are reliably sheared off. The tapping of aluminium, grey cast iron and brass requires taps with a short chamfer lead length, regardless of whether through or blind holes are required. In these materials a long chamfer lead length would act as a core drill with chip breaker grooves and would only drill the tapping size hole to the major diameter instead of cutting a thread. Straight fluted taps without spiral point are general purpose tools and have the disadvantage of not showing optimum results in particular materials. It’s well worth the effort to take the trouble of ascertaining the most suitable tool for any given metal-cutting task. through hole blind hole 786 GUHRING