Countersunk head self-tapping screws are made of metal materials, also known as flat head screws, and are now used in electronic machinery, digital products, decoration, electrical equipment and other fields. So how to use countersunk head tapping screws? What precautions? Now, let Haoyue Quan Hardware Xiaobian summarize today.
Generally, after the countersunk head self-tapping screw is installed, the appearance of the part is smooth and there will be no bulge. Its tightly fixed part is divided into thin and thick parts. Thickness refers to the relative ratio of the thickness of the part to the thickness of the countersunk head tapping screw, the former should be greater than the latter. When tightening, there will be some threads on the outside, but one thing to note is that the countersunk head screws must be tightened.
Phillips Slotted Pan head tapping screw
Also, the thickness of the part is less than the head thickness of the countersunk head tapping screw, which is another case. In most mechanical equipment, there will be sheet metal parts, such as the connection between the equipment and the sheet metal part cover, and the door connection between the boxes. Because the thickness of the fastening portion is small, the screw through the hole forms a tapered hole. When tightening the countersunk head tapping screw, the head of the screw does not press the sheet metal part, but the bottom of the screw and the top of the threaded hole squeeze each other to death. Because of this, sometimes we feel that the screws are extra tight, but the sheet metal isn't really tight.
External hexagon thread self-tapping screw
In the process of installing countersunk head tapping screws, the reaming taper should be less than or equal to 90 degrees and should not exceed 90 degrees. If there are many holes punched by countersunk head screws on the part, it is necessary to maintain accuracy and avoid deviation during processing to ensure the appearance after assembly. If there is a small error, it can be adjusted and tightened slightly. But the diameter of the screw can not exceed 8mm, this point should be remembered. If the countersunk head tapping screw is thicker than the sheet metal thickness, you will need to replace the smaller screw or enlarge the hole. In order to avoid loose parts, it is recommended not to enlarge the reaming diameter.
All in all, you must be careful when installing countersunk head tapping screws. One is to ensure a smooth installation, and the other is to make the installation effect ideal. The above is a summary of the use methods and precautions of countersunk head self-tapping screws. I believe reading this article will help you.
