4 common types of soldering irons
1. External heating soldering iron
It consists of soldering iron head, soldering iron core, shell, wooden handle, power lead, plug and other parts. Because the soldering iron tip is installed inside the soldering iron core, it is called an externally heated soldering iron. The soldering iron core is a key component of the electric soldering iron. It consists of a heating wire wound in parallel on a hollow porcelain tube. The mica sheet in the middle is insulated, and two wires are drawn out to connect to the 220V AC power supply.
There are many specifications for external heating soldering irons, commonly used ones are 25W, 45W, 75W, 100W, etc. The higher the power, the higher the temperature of the soldering iron tip. The power specifications of soldering iron cores are different, and their internal resistances are also different. The resistance of a 25W soldering iron is about 2kΩ, the resistance of a 45W soldering iron is about 1kΩ, the resistance of a 75W soldering iron is about 0.6kΩ, and the resistance of a 100W soldering iron is about 0.5kΩ.
The soldering iron tip is made of copper material. Its function is to store and conduct heat. Its temperature must be much higher than the temperature being soldered. The temperature of the soldering iron has a certain relationship with the volume, shape, length, etc. of the soldering iron tip. When the volume of the soldering iron tip is relatively large, the holding time will be longer. In addition, in order to adapt to the requirements of different soldering materials, the shapes of soldering iron tips are different. Common ones include cone, chisel, round bevel, etc.
2. Internal heating soldering iron
It consists of handle, connecting rod, spring clip, soldering iron core and soldering iron tip. Because the soldering iron core is installed inside the soldering iron head, it heats up quickly and has a high heat utilization rate. Therefore, it is called an internally heated soldering iron. The common specifications of internal heating soldering irons are 20W and 50W. Due to its high thermal efficiency, a 20W internal heating soldering iron is equivalent to an external heating soldering iron of about 40W.
The rear end of the internal heating soldering iron is hollow and is used to be connected to the connecting rod and fixed with a spring clip. When the soldering iron tip needs to be replaced, the spring clip must be withdrawn first and the front end of the soldering iron tip must be clamped with pliers. Pull it out slowly, remembering not to use too much force to avoid damaging the connecting rod.
3. Constant temperature soldering iron
Since the constant temperature electric soldering iron head is equipped with a magnet-type temperature controller, the temperature control is achieved by controlling the power-on time. That is, when the electric soldering iron is energized, the temperature of the soldering iron rises. When it reaches the predetermined temperature, the strong magnet sensor reaches When the Curie point reaches the Curie point, the magnetism disappears, causing the magnetic core contacts to disconnect, and then the power supply to the soldering iron is stopped; when the temperature is lower than the Curie point of the strong magnet sensor, the strong magnet regains its magnetism and attracts the magnetic core switch. The permanent magnet in the switch connects the contacts of the control switch and continues to supply power to the soldering iron. By repeating this cycle, the purpose of controlling the temperature is achieved.
4. Soldering iron
The desoldering iron is a desoldering tool that integrates a piston type desoldering device and an electric soldering iron. It has the characteristics of convenient use, flexibility and wide application range. The disadvantage of this desoldering iron is that it can only desolder one solder joint at a time.
