Classification of Bolt Nut and Washer: According to the force mode of Bolt Nut and Washer connection, it is divided into ordinary and reamed hole. According to the head shape of Bolt Nut and Washer, there are hexagonal head, round head, square head, countersunk head and so on. Among them, the hexagonal head is the most commonly used. The countersunk head is generally used where connection is required.
Riding Bolt Nut and Washer English name is U-bolt, it is a non-standard part, the shape is U-shaped, so it is also called U-shaped Bolt Nut and Washer. There are threads on both ends that can be combined with screw caps. It is mainly used to fix tubular objects such as water pipes or sheets. The object is like the leaf spring of a car. Because it fixes the object in the same way as a person riding on a horse, it is called a riding Bolt Nut and Washer. According to the thread length, it is divided into two types: full thread and non-full thread.
According to the thread type, there are two types of coarse and fine threads. The coarse thread type is not shown in the logo of Bolt Nut and Washer. Bolt Nut and Washer is divided into eight grades of 3.6, 4.8, 5.6, 6.8, 8.8, 9.8, 10.9, 12.9 according to performance grades. Bolt Nut and Washer is made of low carbon alloy steel or medium carbon. The steel is heat-treated (quenched + tempered), and is generally referred to as high-strength Bolt Nut and Washer, and grades below 8.8 (excluding grade 8.8) are generally referred to as ordinary Bolt Nut and Washer.
Ordinary Bolt Nut and Washer can be divided into three grades: A, B, and C according to the production accuracy. A and B grades are refined Bolt Nut and Washer, and C grade is crude Bolt Nut and Washer. For steel structure connecting Bolt Nut and Washer, unless otherwise specified, it is generally ordinary crude C-grade Bolt Nut and Washer. The processing methods of different grades are different, and the corresponding processing methods are usually as follows: ①The bolts of grade A and B Bolt Nut and Washer are processed by lathes, with smooth surface and accurate size. The material performance grade is 8.8, and the production and installation are complicated. , The price is high, it is rarely used; ②The C-grade Bolt Nut and Washer is made of unprocessed round steel, the size is not accurate enough, and its material performance grade is 4.6 or 4.8. Large deformation during shear connection, but convenient installation and low production cost, it is mostly used for tensile connection or temporary fixation during installation.
