How to Weld Branch Pipes Safely?

01 Choose the right solder

Welding of copper and copper: You can choose phosphorus copper solder or phosphorus copper solder with low silver content, such as 2% or 5% silver-based solder. This kind of solder is relatively cheap, has a good solution, uses a gap filling and wetting process, and does not require flux.

02 Safety confirmation before operation:

1. Roll call and health status confirmation of construction workers, and confirmation of construction workers’ work clothes (hard hats, clothing, safety bags, safety shoes, etc.).

2. Describe the working place and working environment, and then divide the work. Explain the content, methods and sequence of the work, and conduct hazard prediction activities.

3. Make a "Construction Plan" and formulate the person in charge of each group.

4. Explain possible accidents such as electric shock, fire, etc., and provide guidance on the correct use of electric machinery.

5. Explain the place where "no one should enter".

6. An application must be made when using an open flame. If open flame operations are required due to special circumstances such as construction, the approval procedures must be completed in advance according to regulations and then approved by the person in charge of on-site safety.

7. Take appropriate fire safety measures; workers should abide by fire safety regulations. Follow local codes and receive guidance from the fire department.

8. Inventory tools. Please also take inventory of the tools after finishing work the day before, and replenish the refrigerant in the piping system if necessary to avoid running out of refrigerant.

03 Precautions during welding process

1. Be sure to use a welding gun with a fire prevention valve to ensure safety.

2. Be careful not to be burned by flames and heating parts.

3. Handle the gas cylinder carefully and be careful of gas leakage.

4. Remove combustible materials from around. If it cannot be moved, take effective fire prevention measures (such as wrapping it with a fireproof cover, etc.) and ventilate frequently to prevent the inhalation of harmful gases.

5. Operations around branch pipe joints and pipe ends should be carried out from below as much as possible. It is difficult to control the amount of heating when working at high places, and it is easy to melt the welded parts of the branch pipe itself and cause leakage.

04 Check whether the welding is unqualified

1. Overburning: The appearance is judged as burn marks and rough pitting in the welding area, the oxide scale of the pipe fittings is severely peeled off, and the color of the copper pipe is water white.

2. Porosity: Small pinholes and bubbles appear on the surface of the welding area.

3. False welding and slag inclusion: The surface solder is obviously not fused, the flame contacts the workpiece during welding and is obviously reddish, sparks or oil smoke is emitted, and the solder cannot be fused.

4. Burning damage: The edge of the weld is burned into a rotten state by the flame, but it is not completely burned through, and the pipe wall itself is burned.