Comparison of welding connection with rivet and bolt

1., do not need to drill holes in the steel, not only saves time and labor, but also does not reduce the cross-sectional area of the material, so that the material is fully utilized. 2. any shape of the component can be directly connected, generally do not need auxiliary parts. The connection structure is simple, the transmission path is short, and the utility model has wide application range. 3., the welding joint has good air tightness and water tightness, and the structure rigidity is larger, and the structure is good in integrity. However, the weld joint also has the following disadvantages: 4. due to the high temperature, the heat affected zone is formed near the weld, the microstructure and mechanical properties of the steel are changed, and the material is brittle. 5. welding residual stress increases the possibility that the brittle failure in the structure, and reduce the pressure bar stability bearing capacity, the residual deformation will make the component size and shape change, correction work. 6., the welding structure has continuity, and once the local cracks are produced, it can be easily extended to the whole. When designing the welding structure, the above-mentioned characteristics of welding connection should be taken into consideration. When the important welding structure is encountered, the structural design and welding process should be closely coordinated. Nowadays, more and more people are paying attention to the development of steel structural bolts by using steel structural bolts to make fixed equipment. Steel bolts are mainly used in permanent or long lasting equipment and buildings. Bridges and skyscrapers, for example. Bolts of steel structures can be connected or welded. There is a big difference between them. Let's talk about it today. If the high strength, that is, the steel structure bolt is used in the form of connections, then the stress of its bolts will be relatively small, in this case the probability of deformation is also relatively small. If the steel bolts are welded, the stresses will increase considerably. Steel bolts, if welded, will have much greater strength than connections. We are in actual use, in order to make the steel structure bolt stress is relatively small, so that the intensity is relatively large, we use the first steel structure bolt connection, and then welding. In this way, pre design requirements can be achieved. After the steel structure welding bolt once good to cannot remove, so before welding to clear the problem, because sometimes we only temporary use of steel structure bolt, so this is not the time to carry out the welding operation. As long as the high strength bolts can be connected, and if you want to steel structure bolts do long-term fixed together, you can bolt welding operation, this must pay attention to. There are two kinds of connection methods for steel bolts. One is the cold working connection method of high strength bolts, and the other is the method of hot working connection of high strength bolts. We can make the choice according to the different requirements at the time of production and processing. The cold processing connection is a rigid connection, while the hot processing is flexible connection. High strength bolt connection can effectively improve fatigue strength, and has less stress and deformation. The welding joint is mainly to improve the overall strength. Welding is generally carried out after high-strength bolts. For a dismountable structure connection bolt, welding and then become one, so most is the transportation and other reasons the equipment structure is divided into several parts, transported to the site in each part is connected by bolts (if will not move, can be welded). The biggest difference is the cold processing connection and the hot working connection. The stress is different. Bolt is better than bolt. One is rigid connection, one is flexible connection, the requirements are not the same, 1, convenient transportation. 2. Convenient lifting. 3. Hoisting safety. 4, removable and not removable. Some facilities also use high strength bolts for the steel to spread out some stresses. Prevent future weld problems.

Strength can meet the design requirements, but high-strength bolts are generally used in dynamic load components, welding is generally used for static load.

1. ordinary bolt points A, B, C three kinds. The first two are refined bolts, less used. Ordinary bolts generally refer to class C plain bolts.

2., in some temporary connections and disassembly of the connection, commonly used C class bolts. Common bolts used in building structures are M16, M20 and M24.

3. the material of high strength bolt is different from ordinary bolt. High strength bolts are generally used for permanent connections. Commonly used are M16~M30.

4. the bolt connection of the main component of the building structure is usually made of high-strength bolt connection.

Last one：Coating construction technology of steel structure
Next article：steel truss