Steps of copper pipe welding
1: Prepare all kinds of welding equipment, check whether the number of gases in the oxygen cylinder and ethyl cylinder meets the requirements, and check whether the connection line of the equipment meets the requirements of use.
2: Welding personnel to do a good job of personal protection.
3: open the valve of the gas bottle, adjust the oxygen pressure reducer to control the outlet pressure, the value of the pressure is about 0.2 MPa, adjust the pressure reducer of the ethyl block, the pressure is between 0.01 and 0.025 MPa.
4: Open the regulating valve of the ethyl gas, first slowly for ignition, and according to the material of the copper tube for the size of the adjustment, the size of the flame can be moderate.
5: Open the oxygen adjustment valve, make the burning flame moderate, showing a neutral flame can be.
6: The flame centre of the flame is about 4 mm away from the soldered copper, and the pipe is perpendicular to the soldering place for heating, until the colour of the copper pipe becomes dark red.
7: Apply brazing flux and heat it until the solder is fully melted and can fill the weld seam evenly.
8: Remove the flame and fix the soldered parts so that there is no misalignment between the two copper tubes soldered.
9: Close the valves of the ethylene gas and oxygen, and adjust the value of the pressure reducer.
10: check the welding, finishing tools, clean up the scene.
Copper pipe welding problems
1: welding deformation
In order to ensure the quality of purple copper pipe welding, it is necessary to connect in the high temperature of the flame, in the welding, due to operational reasons, the purple copper pipe is prone to deformation, which leads to a reduction in the sealing performance of the connection of the purple copper pipe.
2: produce air holes
Due to the thermal conductivity of copper material value is large, the welding seam of the crystallisation speed will be faster, high temperature state, melting into the molten pool of a large number of hydrogen can not be excluded in time, in the surface of the copper pipe will form a variety of different sizes of hydrogen empty.
Under the action of high temperature oxidation, copper will be oxidised, the formation of copper oxide, due to water vapour insoluble in copper, the molten pool of the clean speed, when the water vapour can not be evaporated in time, it will be formed in the inner side of the air holes.
3: Formation of cracks
In the welding process, due to the large welding stress, and due to the large amount of heat input, will be formed in the welded joints in the shape of a large column crystals, in the copper pipe contains other substances, will be formed in the crystals at the crystals of the low melting point of the crystals, in the junction of high temperature and low temperature will be the case of local cracking.
