Grade 8.8, 10.9, 12.9, bolts are made of high-strength steel.
8.8 grade bolts commonly used 35 # steel or 45 # steel; 10.9 grade commonly used 40Cr, 35CrMo, 42CrMo; 12.9 grade bolts with 35CrMo, 42CrMo. high-strength bolts of the material 35 # steel or other high-quality materials, made of heat treatment to improve the strength. High-strength bolts can withstand a greater load than ordinary bolts of the same specification.
High-strength bolts related to the introduction:
High-strength bolts are made of high-strength steel, the need to apply a large preload, it is a special wrench on the tightening of the nut, so that the bolt produces a huge and controlled pre-tension, through the nut and the pad, the same size of the pre-pressure on the connected parts are also produced. Under the action of pre-pressure, a large friction force is generated along the surface of the connected parts.
High-strength bolting is to rely on the friction between the contact surfaces of the connecting parts to prevent their mutual slippage, in order to make the contact surfaces have enough friction, it is necessary to improve the clamping force of the components and increase the coefficient of friction of the contact surfaces of the components. The clamping force between the components is based on the pre-tension applied to the bolt, the bolt must be manufactured using high-strength steel.
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