How to quickly identify the quality of Straight groove tap?

2025-09-01 11:36:28

There are countless Self tapping screw brands on the market, and due to differences in materials used and grinding methods, prices and quality are chaotic, leaving buyers confused and unsure of how to choose. Here's how to quickly identify the quality of Straight groove tap.

1. Check if the chamfer of the front thread of the Self tapping screw groove is uniform, and if there is a gap in the cutting edge of the groove. If it is good, it should be in a regular 7-shape, and if it is not good, it should be in an inverted 7-shape or U-shape (it will cause two cuts when exiting the Self tapping screw, which is prone to breakage and affects the accuracy of the thread).

2. Check the heat treatment condition: Pull the Self tapping screw into the air in a parabolic shape (about 1 meter) and drop it flat to see if it breaks. If it breaks, it indicates high brittleness and poor heat treatment quality.

3. Knock off the Self tapping screw and see if its fracture surface is diagonally long. The molecular particles (metallographic structure) in the fracture surface are fine, indicating that the heat treatment and material are good. If it is flat or diagonally short, the molecular particles (metallographic structure) are coarse, which is not good.

The quality of Straight groove tap mainly depends on their raw materials, heat treatment, groove shape, accuracy, equipment, speed, processed materials, hardness, and the quality of the operators, among other factors.

When choosing an Wire Thread tap, special attention should be paid to the original material, heat treatment, and groove shape of the Self tapping screw. It is recommended to choose different types of Straight groove tap for different machining holes.