There are many ways to weld stainless steel pipes by hand. Among them, manual arc welding is the most common and the most commonly used one.
Manual arc welding methods include: butt TIG welding connection, socket TIG welding connection.
Reliable connection and simple pipe fitting structure.
1. Difficult operation and high construction cost
2. There is a strong heat source and live operation, and there are fire safety hazards during operation;
3. It is difficult to do a good job in the protection of the weld during on-site operation, resulting in peroxidation of the inner wall of the stainless steel pipe, and the oxide layer cannot be removed after welding, which is easy to corrode.
The high temperature is generated by the arc, which melts the electrode and the workpiece and forms a weld, and the length of the arc is adjusted by human hands. In practical application, according to the welding characteristics of stainless steel, the amount of heat input should be reduced as much as possible, and two methods of manual arc welding and tungsten argon arc welding are generally adopted. 100 mm is filled with argon arc welding, 100 mm pipes with a wall thickness of less than 5 mm are fully argon arc welded, and pipes with a wall thickness greater than or equal to 5 mm are equipped with argon arc priming and arc welding.
During the welding process, there are some technical details that need to be paid attention to. For example, the use of small specifications can prevent intergranular corrosion, thermal cracks and deformation, and the welding current is 20% lower than that of mild steelIn order to ensure the stable combustion of the arc, DC reverse connection is adoptedThe arc of short arc welding should be slow, fill the arc pit, and the surface in contact with the medium should be welded lastWhen welding multiple layers, pay attention to controlling the temperature between layers.