A weldment preheating, copper electrode drying:
In order to improve the welding quality. Recommendations can be preheated before welding weldment to 300-350 degrees. Electrode baking for 1 hour at 150-200.
Two transport of methods:
Copper electrode welding shipped straight strip method available. The faster the better. To reduce the metal oxide. License within the scope of the weldment. Increasing the electrode diameter and welding current. Welding V-shaped or X-shaped groove when. The roots may appear incomplete penetration and other defects. The main reason is due to the electrode is too thick. Bevel angle is small. Too far away from the roots of the arc. Coupled with fast thermal conductivity of copper. Arc calorie deficiency. Therefore, in order to ensure the root penetration. Bevel angle should be appropriately increased or increased clearance. V-shaped groove when multi-layer welding. The first layer with a diameter of 3-4 mm rod is best. After the layers of electrode diameter can be increased and made a lateral swing. When welding, the arc should be positive for the pool. Blown to one side to avoid the groove metal. Welding seam along the center of constant feeding. To move the welding direction. Prevent the flow of liquid metal and slag generated weld puddle outside the tumor. When replacing the electrodes must act quickly. Should be in the welding high temperature state of the central crater 10 mm away from the weld has been on the arc. Then back to the original bath. After welding continues to fill the bath.
3 Welding sequence:
Copper electrode welding in order to reduce the time weldment distortion. Welding gap length less than 500 mm. Can be welded directly from one end to the other end of the through-welding. Such as weld length greater than 500 mm. Can be welded to the ends of the center. Some methods of welding steel to prevent deformation taken. In the welding of copper can also be used.
4 welding current and electrode diameter:
Copper electrode diameter and welding current should be based on the thickness of weldments. The beginning of the weld, the outer weldment profiles and cooling conditions to choose. Typically, the welding current is 40-50 times the electrode diameter.
