The following describes the various screw machining methods:
Generally, it refers to the method of machining thread on workpiece with forming tool or grinding tool, mainly including turning, milling, tapping, threading, grinding and whirlwind cutting, etc.
On the thread milling machine, the disc milling cutter or comb milling cutter is used for milling. Disc milling cutter is mainly used for milling trapezoid external thread of screw rod, worm and other workpieces. Comb milling cutter is used for milling internal and external common thread and taper thread.
It is mainly used to process the precision thread of hardened workpiece on the thread grinder. According to the different cross-section shape of grinding wheel, there are two kinds of grinding: single line grinding wheel and multi line grinding wheel.
The nut type or screw type thread lapping tool is made of soft materials such as cast iron. The parts of the processed thread on the workpiece with pitch error are grinded by forward and reverse rotation to improve the pitch accuracy. The hardened internal thread is usually eliminated by grinding to improve the accuracy.
TAPPING AND THREADING
Tapping is to use a certain torque to screw the tap into the pre-drilled bottom hole on the workpiece to machine the internal thread. Threading is to cut the external thread on the bar (or tube) workpiece with a die.