About the principle and advantages of butt welding machine

Update:28 Nov 2020
Summary:

1. Butt welding type: 1. Resistance butt welding (power […]

1. Butt welding type:
1. Resistance butt welding (power frequency AC)
Features: The weldment is first contacted and pressurized and then energized. When it reaches the fixed plastic state, the upset forging completes the welding, the welding surface needs to be strictly cleaned, and the shape of the joint after welding is symmetrical, but
The quality of the joint is poor and the required power rate is large.
Equipment needed: The simplest, generally small, so butt welding machines are acceptable.
Applications: Low-carbon steel bars and tubes with a diameter of less than 20mm, and non-ferrous metals with a diameter of less than 8mm.
2. Continuous flash butt welding
Features: first energize, and then make the two weldments contact, firstly form a lintel at the contact point and heat it to melt, showing sparks (flashing) and moving closer, enough heating
When it is quickly approached, the live upsetting is performed to complete the welding. The quality of the joint is higher, and the quality before welding is higher. There is no need to clean the weldment before welding, and the required electric rate is larger.
Required equipment: small-scale manual, large-scale program control of hydraulic and welding parameters.
Application range: Important components of various materials such as: bars, pipes, plates, profiles, steel bars, drill pipes, tools, automobile wheels, etc.
3. Preheating flash butt welding
Features: First use flash method or resistance method for preheating. When welding by continuous flash butt welding, the joint quality is higher, the heating zone is larger, and the amount of metal burned is less.
Less power is required.
Required range: small and manual, large-scale programs are controlled by hydraulic and welding parameters.
Application scope: Important components of various materials such as bars, pipes, profiles, steel bars, steel rails, drill pipes, tracers, tool car rims, etc.
The main component of the butt welding machine is a step-down transformer. The two ends of the secondary coil are the welding workpiece and the welding rod. When working, the arc is ignited, and the welding is carried out in the high temperature of the arc.
The strip is welded in the gap of the workpiece. Because the iron core of the welding transformer has its own characteristics, it has the characteristic of a sharp drop in voltage, that is, the voltage drops after the welding rod is burned;
When the electrode is short-circuited by adhesion, the voltage drops sharply.
Second, the principle of butt welding machine
What the butt welder actually uses is that when the workpiece is in contact with C, the resistance will generate heat, so as to achieve the purpose of heating the workpiece and melting the metal surface. The common crystal grain, the structure and composition of the weld are close to the base metal, so it is relatively easy to obtain a welded joint of equal strength and plastic. In the flashing process, it has the self-protection function of exhausting air and reducing metal oxidation, so that there are fewer defects such as weld inclusions and incomplete penetration.