Copper nut with you to understand the manual or machine method to detect the quality of bolts.

Bolt detection is divided into manual and machine. Manual is the most primitive and common method of consistency detection. In order to minimize the outflow of defective products, the personnel of general production enterprises inspect the packaged or shipped products visually in order to eliminate the defective products. Another way is automatic machine testing, mainly magnetic particle testing. Embossed nut

Magnetic particle testing is based on the interaction of magnetic flux leakage and magnetic powder at the defect of bolt. In view of the difference of magnetic permeability between bolt and steel, the magnetic field at the discontinuity of these materials will change after magnetization, and magnetic flux leakage will occur on the surface of part of the workpiece at the leakage of magnetic flux. The magnetic field attracts the accumulation of magnetic powders at the defect area, i. e. magnetic traces. Under appropriate illumination conditions, the defect location and shape are displayed. The accumulation of these magnetic powders is observed and explained, and the purpose of eliminating the defective products is achieved.

There are many names for bolts. Everyone may call them different. Some people call them bolts, some call them bolts, and some call them fasteners. Although there are so many names, but the meaning is the same, are bolts. Bolts are a general term for fasteners. Bolt is a tool for tightening machine parts step by step by step by using the physical and mathematical principles of oblique circular rotation and friction of objects.

Bolts are indispensable in daily life and industrial production. Bolts are also known as industrial rice. It can be seen that bolts are widely used. Bolts are used in electronic products, mechanical products, digital products, electrical equipment, mechanical and electrical products. Bolts are also used in ships, vehicles, water projects and even chemical experiments. Bolts are used in many places anyway. Especially for precision bolts used on digital products. DVD, miniature bolts for cameras, glasses, clocks and watches, electronics, television, electrical products, musical instruments, furniture and other general bolts; for engineering, construction and bridges, large bolts and nuts are used; for transportation equipment, aircraft, trams, automobiles, etc., large bolts and small bolts are used. Bolts play an important role in industry. As long as there is industry on the earth, the function of bolts will always be important.

Generally, the countersunk head is used in the place where the smooth surface of the joints is required, because the countersunk head can be screwed into the parts. The round head can also be screwed into the parts. The tightening force of the square head can be larger, but the size is large. In addition, in order to meet the need of locking after installation, there are holes in the head and in the rod, which can keep the bolt from loosening when it is vibrated. Some bolts have no threaded bars to be thin, called thin waist bolts. This kind of bolt is advantageous to the connection under the variable force. There are special high strength bolts on the steel structure, the head will be bigger, and the size will also change. In addition, there are special uses: T-groove bolts, machine tool fixtures used the most, special shape, head side to be cut off. Ground bolts, which are used to connect the machine to the ground, have many shapes. U-shaped bolts, as mentioned above. Wait. There are special studs for welding, one end with thread and one end without thread, which can be welded on parts, and the other side can be directly screwed nuts.