U-bolt grade and method of purchase
U-bolts are bolts used in fasteners and are used primarily in special construction and automotive applications. Today, we will tell you about the grade and method of U-bolt, and I hope to help everyone.
U-bolt grade introduction
U-bolt grades are mainly divided into high-strength U-bolts and ordinary U-bolts. High strength is mainly used in some projects such as outdoor engineering, wind power or dynamic machinery. The tensile strength is relatively large. Generally, U-bolts can be used on some small machines, such as turbines, mainly depending on the application environment and high operation mode. U-bolts are used more and more widely. Commonly used 8.8s and 10.9s two intensity levels, of which 10.9 level is mostly. Ordinary U-bolt strength grades are low, generally 4.4, 4.8, 5.6 and 8.8.
U-bolt selection method
1. From the perspective of strength level: High-strength U-bolts are used more and more widely. Commonly used 8.8s and 10.9s two intensity levels, of which 10.9 level is mostly.
2. From raw materials: High-strength U-bolts are made of high-strength materials. The screws, nuts and washers of high-strength U-bolts are made of high-strength steel, usually 45 steel, 40 boron steel, 20 manganese titanium boron steel. Ordinary U-bolts are usually made of Q235 steel.
3. From the point of view of use: U-bolt connection of the main components of the building structure is generally connected by high-strength U-bolts. Ordinary U-bolts can be reused, and high-strength U-bolts are not reusable. High-strength U-bolts are typically used for permanent connections. The high-strength U-bolt is a pre-stressed U-bolt. The friction type uses a torque wrench to apply the specified pre-stress, and the pressure-type type unscrews the plum head. Ordinary U-bolts have poor shear resistance and can be used in secondary structural parts. Ordinary U-bolts need only be tightened.
4. From the characteristics of the force: The high-strength U-bolt applies pre-tension and transmits external force by friction. Ordinary U-bolt connection relies on the shear resistance of the bolt and the pressure of the hole wall to transmit the shear force. When the nut is tightened, the pre-tension is small, and the influence is negligible. The high-strength U-bolt is not only high in material strength, but also The U-bolt exerts a large pre-tension, which causes a pressing force between the connecting members, so that there is a large friction force perpendicular to the screw direction, and the pre-tension, anti-slip coefficient and the type of steel directly affect the bearing of the high-strength U-bolt. force.
The above is about the U-bolt grade and the purchase method. I hope everyone can understand the U-bolt grade and the purchase method.
