Thread Grinding:

It is mainly used to process precision threads of hardened workpieces on thread grinding machines. According to the shape of the cross-section of the grinding wheel, it can be divided into two types: single-line grinding wheel and multi-line grinding wheel.

The pitch accuracy that can be achieved by single-line grinding wheel grinding is 5 to 6 grades, and the surface roughness is R1.25 to 0.08 microns, which is more convenient for grinding wheel dressing. This method is suitable for grinding precision screws, thread gauges, worms, small batches of threaded workpieces and relief grinding precision hobs. Multi-line grinding wheel grinding is divided into longitudinal grinding method and plunge grinding method. In the longitudinal grinding method, the width of the grinding wheel is smaller than the length of the thread to be ground, and the grinding wheel moves longitudinally once or several times to grind the thread to the final size. The width of the grinding wheel of the plunge grinding method is larger than the length of the thread to be ground. The grinding wheel is cut into the surface of the workpiece radially, and the workpiece can be ground well after about 1.25 revolutions. The productivity is high, but the accuracy is slightly lower, and the grinding wheel dressing is more complicated. Plunge grinding is suitable for relief grinding of large batches of taps and for grinding certain threads for fastening.