Soldering copper pipes yourself
Copper pipe, like all other pipes, can be used for the installation of plumbing, heating, etc. And, although this is a very expensive pleasure, in some cases, its long service life can justify itself. Copper pipe is not cooked? it must be soldered. Without a certain skill to independently perform such work will be difficult, although it is possible.
High temperature soldering
The peculiarity of soldering is the softening of the metal during firing and the use of refractory solder consisting of silver and copper. To achieve a high-quality weld, the temperature must be at least 450°C. But it is also impossible to overheat, otherwise copper will lose its strength. The welded joint should cool down independently, without forced cooling, for example, with water. High-temperature brazing is used for pipes whose diameter is more than 28 mm, and the temperature of the working medium of the pipeline is above 130°C. This technology is used in the gas industry, heating systems, etc.
Low temperature soldering
Soldering at a temperature below 450°C is called low-temperature and is used for pipes of small diameter - up to 28 mm. This is the most common application technology for the installation of water supply. Solders are used solders with a lower melting point.
Variety of solders
As you understand, for different temperature soldering should be your solder.
- For soldering at high temperatures, solder is used in the form of a rod with a melting point of 900°C. The solder contains copper, silver and other additional metals. The seam formed from the refractory solder is of high strength.
- The solder for low-temperature soldering is 3 mm thick and is wound into a coil. It contains silver, tin, lead and additives.
Flux Application
Fluxes are used to set the solder and spread it evenly. For high temperatures, use a flux with a melting point above 450°C, and for low temperatures - up to 450°C. Flux cleans the soldering site from oxidation, which contributes to the strong adhesion of the solder to copper.
Use fittings
Pipe fittings use a variety of fittings. It can be turns, tees, crosses, transitions to the thread, etc. They are selected according to the diameter of the pipe and have a gap.
High temperature soldering
For soldering the pipe at high temperature, use a torch connected to propane or acetylene. A properly tuned burner has a bright blue flame. The surface of the connection is heated in a circle up to 750°C. Properly heated surface of the pipe should have a dark cherry color.
Low temperature soldering
The soldering of the connections is carried out by a gas burner connected to a propane-butane gas cylinder. In some cases, you can use an electric soldering iron. The flame from the gas burner should move across the entire surface of the connection for full warm-up. After melting the solder, the burner flame is removed. Liquid solder should evenly fill the joint gap. Let's look at the sequence of all the work:
- Brush the metal must be cleaned the outer surface of the edge of the pipe and the inside of the fitting. Then sandpaper them to a brilliant color.
- Brush apply paste-like flux to the surfaces to be soldered and join them.
- Ignite the burner and start heating the pipe joint with the fitting evenly. After full warming up, conduct solder all over the joint until the gap is completely filled. Remove the burner and allow the joint to cool to room temperature.
If you have done everything correctly, the solder should fill all the gaps between the pipe and the fitting, forming a tight joint.
Security measures
When soldering with a gas torch, do not forget that you are working with an open flame. Remove all flammable objects. Perform the work in a ventilated area. During the melting of solder and flux, toxic substances can be released, so try to breathe as little as possible. To avoid burns, use special gloves and protective clothing. If you use acid soldering instead of flux, wear rubber gloves and clothing that is resistant to contact with acid.