Welding Equipment temperature control
The molten pool temperature, a direct impact on the quality of the weld, the pool temperature is high, the molten pool is large, good fluidity of molten iron, easy fusion, but too high, the molten iron easy to drip, single welding double-sided forming the back burn through, Welding tumor, forming is difficult to control, and the plastic joints down, bending easy to crack. Bath temperature is low, the molten pool smaller, hot metal dark, poor mobility, easy to produce not penetration, not fusion, slag and other defects.
Bath temperature and welding current, electrode diameter, electrode angle, arc burning time is closely related to the relevant factors to take the following measures to control the molten pool temperature.
1, welding current and electrode diameter: According to weld space position, welding level to choose the welding current and electrode diameter, open welding, the choice of welding current and electrode diameter larger, vertical, transverse position is small. Such as 12mm flat butt welding of the bottom cover welding φ3.2mm, welding current: 80-85A, filling, cover layer selection φ4.0mm electrode, welding current: 165-175A, a reasonable choice of welding current and electrode diameter, Easy to control the molten pool temperature, is the basis of weld formation.
2, the transport method, the circle-shaped article of the molten pool temperature is higher than the crescent-shaped transport temperature, crescent-shaped transport temperature is higher than the serrated transport of the pool temperature in the 12mm flat seal bottom, using zigzag , And the amplitude of the swing and the pause on both sides of the groove, the effective control of the molten pool temperature, the size of the hole is basically the same, the root groove does not form the possibility of burnt and burn down the probability of not penetrating The improvement, so that the board butt welding single-sided welding double-sided forming is no longer a difficult point.
3, the electrode angle, the angle of the electrode and welding direction at 90 degrees, the arc concentration, the pool temperature is high, the angle is small, arc dispersion, the pool temperature is low, such as 12mm flat bottom, electrode angle: 70 degrees, so that the bath temperature has declined, to avoid the back of the welding tumor or from the high. Another example, in the 12mm plate welding seal for the bottom of the electrode, the joints with 90-95 degrees of the electrode angle, so that the rapid increase in the molten pool temperature, melt hole can be successfully opened, forming a more flat back, effectively control the joint point Concave phenomenon.
4, arc burning time, φ57 × 3.5 tube horizontal fixed and vertical fixed welding practice teaching, the use of broken arc welding, sealing the bottom of welding, the arc off the arc frequency and the direct impact of the bath temperature, due to If the temperature of the molten pool is too high, the temperature of the molten pool can be controlled only by the arc burning time. If the temperature of the molten pool is too high and the temperature of the molten pool is too high, Larger hole, can reduce the arc burning time, so that the pool temperature decreases, this time, the smaller melt holes, tube forming a moderate internal height, to avoid the RF Welding internal pipe weld ultra-high or produce welding tumor.