1. Resistance welding is to use the resistance heat generated inside the weldment to conduct, heat and melt the metal from the high temperature zone to the low temperature zone, and realize welding. It belongs to internally distributed energy.
2. Resistance welding seam is solidified or collective crystallization under pressure, belonging to the category of pressure welding, with forging characteristics.
3. Because the welding heat is concentrated and the heating time is short, the heat affected zone is small, and the welding deformation and stress are small. Therefore, correction and heat treatment are usually not required after welding.
4. Generally, welding materials such as welding, welding wire, welding flux and shielding gas are not required, and the welding cost is low.
5. The nugget of resistance welding is always surrounded by solid metal, and the molten metal is isolated from the air. The welding metallurgical process is relatively simple.
6. Simple operation, easy to realize mechanization and automation, and good working conditions.
7. With high productivity, it can be arranged on the assembly welding production line together with other processes. However, flash welding needs to be isolated due to spark splashing.
8. Due to the high power, mechanization and automation of resistance welding equipment, the one-time investment of equipment is large and maintenance is difficult. Moreover, the commonly used high-power single AC welding machine is not conducive to the normal operation of the power grid.
9. The lap joint of spot welding and seam welding not only increases the quality of the component, but also reduces the tensile strength and fatigue strength of the joint.
10. At present, there is no reliable nondestructive testing method for resistance welding quality, which can only be checked by process samples, destructive tests and various monitoring technologies.
Advantages of resistance welding
(1) When the nugget is formed, it is always surrounded by a plastic ring, the molten metal is isolated from the air, and the metallurgical process is simple.
(2) The heating time is short and the heat is concentrated, so the heat affected zone is small and the deformation and stress are small. It is usually unnecessary to arrange correction and heat treatment procedures after welding.
(3) There is no need for filler metals such as welding wires and electrodes, and welding materials such as oxygen, acetylene and hydrogen, so the welding cost is low.
(4) Simple operation, easy to realize mechanization and automation, and improved working conditions.
(5) With high productivity and no noise and harmful gas, it can be programmed into the assembly line together with other manufacturing processes in mass production. However, flash butt welding needs to be isolated due to spark splashing.
Disadvantages of resistance welding
(1) At present, there is a lack of reliable nondestructive testing methods, and the welding quality can only be checked by destructive tests of process samples and workpieces, as well as by various monitoring technologies.
(2) The lap joint of spot welding and seam welding not only increases the weight of the component, but also causes low tensile strength and fatigue strength of the joint due to the included angle around the weld nugget of the two plates.
(3) The high power, mechanization and automation of the equipment make the equipment more expensive and difficult to maintain, and the commonly used high-power single-phase AC welding machine is not conducive to the balanced operation of the power grid。
Amanda
Company: Baoji Dynamic Trading Co., Ltd
Country:China
Add:Baoti road,Jintai,Baoji city,Shaanxi,China
Cel/Whatsapp :+86 18309262795
Website:www.jm-titanium.com
