Methods to improve the welding quality of electric soldering iron
1. When welding with an electric soldering iron, it is necessary to ensure that each solder joint is firmly welded and in good contact, so as to ensure the welding quality.
2. A good solder joint requires that the tin spot is bright, smooth and burr-free, and the tin content is moderate. Tin and the object to be welded are firmly fused. There should be no virtual welding and false welding.
3, pay attention to prevent the problem of virtual welding and false welding: virtual welding is that only a small amount of tin is welded at the solder joint, resulting in poor contact, intermittent. False welding means that it seems to be welded on the surface, but it is actually not welded. Sometimes, when it is pulled by hand, the lead will be pulled out of the solder joint.
Only through a lot of serious welding practice can these two problems be avoided.
4, when welding the circuit board, you must control the time. If the time is too long, the circuit board will be burnt or the copper foil will fall off. When removing components from the circuit board, the soldering iron head can be attached to the solder joint, and the components can be pulled out after the tin on the solder joint melts.
5. Flux (rosin and welding oil) is the key when welding. Fresh rosin and non-corrosive welding oil are helpful to complete welding with high quality, and can make the surface smooth and beautiful. Use more flux.
Characteristics of external heating electric soldering iron
1. External heating electric soldering iron
Welding head, soldering iron core, shell, wooden handle, power lead, plug and other parts. welding head is installed in the soldering iron core, which is called external heating electric soldering iron.
2. Components
The core of soldering iron is the key component of electric soldering iron. The heating wire is wound on a hollow porcelain tube in parallel, and the mica sheet in the middle is insulated, and two wires are led out to connect with 220V AC power supply.
3. Product specifications
There are many specifications of external heating electric soldering iron, and the commonly used specifications are mainly 25W, 45W, 75W, 100W, etc. The greater the power, the higher the temperature in welding head.
The internal resistance of soldering iron core is different with different power specifications. The resistance of 25W soldering iron is about 2kω, that of 45W soldering iron is about 1kω, that of 75W soldering iron is about 0.6kω, and that of 100W soldering iron is about 0.5kω.
4, the use of materials
Welding head is made of copper, which is used to store heat and conduct heat. The temperature must be much higher than the temperature to be welded.
The temperature of soldering iron is related to the size, shape and length of welding head. When the volume of welding head is relatively large, it will last longer.
In order to meet the requirements of different weldments, welding head has different shapes, such as cone, chisel, circular inclined plane and so on.
