Copper copper pipe pipe selected TP2 grade copper, copper is pure copper, copper content of 99.97% (the higher the copper content, the better the bacteriostatic effect). China Engineering Construction Standardization Association standard "building water supply copper piping engineering technical regulations" 3.0.1: building water supply copper pipe should be used TP2 grade copper pipe. Because purple copper does not contain heavy metals, it meets the health standard. It is characterized by stable performance, high strength and low coefficient of thermal expansion. So, what should be paid attention to in the welding of copper pipe?
Welding Tumor
Characteristics:
The brazing material flows outside the brazing seam and forms an accumulation.
Formation causes:
1, too much welding thermal efficiency;
2,The brazing material is applied too much or applied in an improper way;
3, Weld seam is not at the same level when welding;
Preventive measures:
1, swing the welding torch back and forth when heating to prevent local overheating;
2, add solder to slide along the weld from the back of the heating position;
3, weldments are positioned smoothly.
Bite edge
Characteristics:
The edge of the weld is burned by the flame into a rotting shape, but not completely burned through, and the pipe wall itself is burned.
Formation causes:
1, welding thermal efficiency is too large;
2, the heating method is wrong.
Preventive measures:
1, using the flame for neutral burn welding.
2, flame swing back and forth welding torch, avoid centralized heating.
Overcooking or corrosion
Characteristics:
Joint surface oxides after welding natural chunks off the joints after wiping clean, there are black spots inlaid in the joint surface.
Formation causes:
1, welding thermal efficiency is too large (temperature is too high);
2, welding time is too long.
3, the use of oxidizing flame welding.
4, repeated welding (filler welding)
Preventive measures:
1, Neutralize the neutral flame welding;
2, Do not repeat welding. Trachoma
Characteristics:
The weld has impurities, resulting in deeper holes on the weld surface.
Formation causes:
1, brazing material or base material itself has oil, impurities or oxide film.
2,The temperature of the weld is too high, causing the phosphorus in the brazing material to volatilize.
3, the heating speed is too fast.
Preventive measures:
1, ensure the cleanliness of brazing material and base material;
2, welding efficiency is appropriate, so that the gas dissolving the high-temperature molten pool is effectively discharged when the weld solidifies
Porosity
Characteristics:
Insufficient heating time, the gas in the liquid Henna seam metal fails to spill out completely, forming holes on the surface or inside.
Formation causes:
1,The fiber material or base material itself has oil or oxidation;
2,The welding speed is too fast, and the gas in the welding is not effectively discharged;
3, the flame is a reducing flame, resulting in reducing hydrogen holes;
Preventive measures:
1, to ensure that the parent material fiber cleanliness;
2, choose neutral flame welding, moderate speed.
