U-shape is generally used in cargo vehicles, it is used to stabilise the chassis and frame of the vehicle. For example, the steel plate spring is U-bolt to connect.

U bolts are widely used, the main use: construction and installation, mechanical parts connection, vehicles and ships, bridges, tunnels and railways.

Main shapes: semi-circular, square right angle, triangle, oblique triangle, etc.

• Material properties, density, bending strength, impact toughness, compression strength, modulus of elasticity, tensile strength, temperature resistance, colour according to the use of the environment.
• Materials commonly used are carbon steel Q235A Q345B alloy steel stainless steel and so on. Among the stainless steel materials are 201 304, 321, 304L, 316, 316L.
• National standard of U-bolt: JB/ZQ4321-2006.
• Material: U-bolt according to the material points are carbon steel Q235, Q345 alloy steel, stainless steel 201 304 316, etc., that is, carbon steel and stainless steel.

Carbon steel is a ‘broad category’ that can be subdivided into mild steel, medium carbon steel, and high carbon steel according to carbon content, strength, and application.

1.low carbon steel ≤ 0.25 % Q235, A36, SS400, S235 soft, easy to bend and weld, low cost construction, pipeline, ordinary bolts
medium carbon steel 0.25-0.60 % 1045, S45C, C45 Strength ↑, moderate toughness, can be heat-treated Shafts, gears, bolts, grade 8.8
High carbon steel 0.60-1.0 %+ 1095, SK5, T8/T10 Hardest and most brittle, wear-resistant, heat-treatable Springs, cutting tools, rails
2. Relationship with "Mild steel
- Mild steel = Low-carbon steel, which is only a subset of carbon steel.
- Thus: all mild steel is carbon steel, but not all carbon steel is mild steel.

3. General properties (in the case of mild steel)
- Tensile strength: 400 - 550 MPa
- Yield strength: ≈ 250 MPa
- Elongation: 20 % or more
- Weldability: excellent (low carbon content reduces hardening cracks)
- Corrosion resistance: poor, zinc plating/painting/coating required
- Magnetism: strong (ferromagnetic)

U-bolt heat tightening is suitable for what occasions. Thermal tightening is the internal control of the medium temperature requirements of the pipeline bolts, in addition to the construction of the fastening, the need to reach a constant temperature or different temperatures in a process of work and then the fastening. And in normal use, the temperature rises, the bolt is subjected to thermal expansion, the gap increases, the need to complete the sealing from zero by hot tightening operation.

In general, the requirements of the internal temperature > 200 ℃ in the equipment, pipelines, etc., need to bolt fastening heat tightening.

Hebei Wanxin Fastener Manufacturing Co., Ltd, the main production of products are: U bolts, steel bolts, ground bolts, flange, double-headed bolts, highways, railways, underground supporting fasteners, a variety of pre-embedded parts, high-strength bolts, high-strength hexagon, scaffolding, through the wire water-stop screws, high-strength nuts, through the wall wire reinforcing stirrups,, step by step, the top bracket, butyl threads, water-stopping steel plate and so on.

With the growing awareness of environmental protection, the environmental performance of U-shaped bolts has also become a focus of attention. In the production process, the use of environmentally friendly materials and processes to reduce energy consumption and pollutant emissions has become an important development direction of the U-shaped bolt industry. Through the research and development of new environmentally friendly materials and improve production efficiency, U-bolt industry is also to achieve the goal of sustainable development to make a positive contribution.

U-bolt as an important type of fastener, in construction, machinery, automotive and other traditional fields, as well as aerospace, new energy and other emerging fields have a wide range of applications. Its unique structure and performance advantages make it an indispensable part of engineering. In the future, with the continuous progress and innovation of science and technology, the application fields and performance of U-shaped bolts will be further expanded and improved, making greater contributions to engineering construction and social development. Environmental protection and sustainable development will also become an important development direction of the U-shaped bolt industry, to promote the industry to achieve a greener, sustainable development.

Zinc is soluble in acids as well as in bases, so it is called an amphoteric metal. Zinc undergoes little change in dry air. In humid air, a dense film of zinc alkali carbonate is formed on the surface of zinc. In containing sulfur dioxide, hydrogen sulfide and marine atmosphere, zinc corrosion resistance is poor, especially in the high temperature and high humidity containing organic acid atmosphere, zinc coating is very easy to be corroded. The standard electrode potential of zinc is -0.76V, for the steel substrate, zinc plating belongs to the anodic plating, which is mainly used to prevent corrosion of steel, the advantages and disadvantages of its protective properties and the thickness of the plating is very large. Zinc coating can significantly improve its protective and decorative properties after passivation treatment, dyeing or coating with gloss protection agent.

Zinc plating is involved in an increasingly wide range of fields, fasteners have been used throughout the mechanical manufacturing, production of galvanised hook and loop mesh, electronics, precision instruments, chemical industry, transportation, aerospace and other major significance in the national economy.

Electrozinc plating works based on the principle of electrolysis. The substrate and zinc are placed in an electrolyte solution containing zinc ions. The substrate is connected to the negative terminal of a DC power supply and the zinc is connected to the positive terminal of a DC power supply. The flow of current causes the zinc metal ions to be reduced and deposited onto the substrate, forming a thin electroplated metal coating. It is also aesthetically pleasing and corrosion resistant. This method of galvanising is commonly used for small-sized parts or products such as fasteners, screws, bolts, wires, automotive parts, etc.