u type generally used in the truck, which is used to stabilize the site and car chassis. For example, the leaf spring is u-bolt connection. U-bolts [1] widely, the main purposes: construction and installation, machinery parts connection, vehicles, ships, bridges, tunnels and railways. Main shape: semicircular, square rectangular, triangular, oblique triangle. 2 Basic information editing 1, material properties density, flexural strength, impact toughness, compressive strength, elastic modulus, tensile strength, heat resistance, color determined according to the use environment. 2, materials commonly used in stainless steel and other alloy steel Q235A Q345B. Wherein the stainless steel has 201 304,321,304L, 316,316L ,. 3, u-bolts national standards: JB / ZQ4321-1997 4, the physical picture