Classification of electric soldering iron and introduction of some practices before use
Electric soldering iron is an artifact for electronic enthusiasts, and the welding of components determines the quality of products. Welding technology is the basic link to ensure welding quality, product quality and reliability. For example, internal heating electric soldering iron, external heating electric soldering iron, constant temperature electric soldering iron, tin absorbing electric soldering iron, etc.
Internal heating electric soldering iron: It is composed of connecting rod, handle, spring clip, soldering iron core and welding head. The soldering iron core of the electric soldering iron is placed in the welding head, which is made by winding a nickel-chromium resistance wire on a porcelain tube.
External heating electric soldering iron: Its welding head is located in the soldering iron core and made of copper alloy material with good thermal conductivity as the matrix. Its welding head is scalable. If the temperature is high, the welding head will be shorter, otherwise, the welding head will be longer.
Constant-temperature electric soldering iron: A magnet thermostat is installed in its welding head to control the power-on time. If the welding temperature is not high and the welding time is not long, a constant temperature electric soldering iron can be used.
Tin-absorbing soldering iron: It is a soldering tool which combines the piston-type tin-absorbing device and the soldering iron. It is flexible and convenient to use and has a wide application range.
Before using the electric soldering iron, it is best to measure the resistance of the power plug to judge whether the electric soldering iron can be used. If the resistance is several thousand ohms available, if the resistance is zero or infinite, it cannot be used. The resistance is zero, indicating that there is a short circuit inside the soldering iron, and the resistance is infinite, indicating that there is an open circuit inside the soldering iron.
Some practices before using electric soldering iron
When the new soldering iron is used for the first time, make sure that the soldering iron head is bright. When the soldering iron is electrified and heated to melt the solder, it is dipped in rosin and contacted with solder wire for many times, and the welding head is evenly plated with a layer of solder. The purpose of this is not only to facilitate the subsequent use, but also to prevent welding head oxidation. For the old soldering iron before use, after long-term use, there will be a layer of oxide on the surface of welding head, which makes it difficult for welding head to eat tin. So only remove the oxide on the surface of welding head with fine sandpaper or file to make its surface bright. Then install a new soldering iron treatment method to evenly coat the surface of welding head with a layer of welding.
In fact, oxygen has nothing to do with the heating of electric soldering iron, which heats and melts solder wire by alternating current. The questioner may say that the electric soldering iron does not eat tin, which is because the electric soldering iron is not used for a long time, which will accelerate the oxidation of the soldering iron core and burn it out, shortening its service life. At the same time, it will also cause welding head to be oxidized or burned to death by heating for a long time. Therefore, the soldering iron no longer eats tin. In the process of not eating tin, there is an oxidation reaction, and the substance reacts chemically with oxygen, in which oxygen provides oxygen. Under normal circumstances, it is slowly oxidized, but the power-on time is too long, and the temperature rises sharply, which provides reaction conditions for the oxidation reaction and accelerates the welding head of the electric soldering iron and the oxidation speed of the soldering iron core.
