Общий каталог Yamawa 2022 - 2023 - страница 1156

Tapping speed and Revolution Speed Tapping Torque

■Conversion table ■Tapping Torque of Cutting type Taps

The torque starts increasing as the threads of chamfer enter the workpiece material. It becomes highest when all threads of chamfer cut into workpiece material, and is in plateau until the chamfer cuts through the workpiece. After that, the torque will decrease until the end of tapping.

■Cutting Torque Line

Cutting torque lines in the test of different kinds of taps, hand tap, spiral fluted tap, spiral pointed tap are shown below.

Tapping Condition Tap : HSS P2 M8×1.25 Bored hole size : 6.8mm Cutting speed : 6.1m/min Cutting oil : Water insoluble oil Workpiece material : S50C Machine : Drilling machine Tapping type : 10mm Through hole Measurement equipment : Piezoelectric torque tester

Type of tap Hand tap (P2) Taper tap (9 threads)

Torque lines

Description

Gentle slope is observed because of less cutting by each cutting chamfer, but longer tapping time is taken than in the other hand taps.

Plug tap (5 threads)

Bottoming tap (1.5 threads)

Spiral fluted tap (P2, 2.5 threads)

Nominal diameter of tap

Spiral pointed tap (P2, 5 threads)

Plateau is observed since whole chamfer threads enter the workpiece material. Tapping time is much shorter than that of the taper tap.

Plateau is also observed since whole short chamfer threads enter the workpiece material. Tapping process time is shorter than that of the plug tap.

Spiral fluted tap pulls out the chips, good choice for blind hole tapping. The cutting torque of spiral fluted taps is smaller than that of the hand taps.

Spiral pointed tap pushes out the chips forward. It is good choice for through hole use. Cutting torque is smallest in all taps.

The cutting torque will change depending on the kind of taps, cutting chamfer, number of flutes, workpiece materials and their hardness, lubrication types, and chips.

Technical Inf