Internal heat type soldering iron definition
The heat element is inside the solder copper head, or is interpreted as "the tip of the soldering iron is placed outside the heating element", so that heat is transferred from the inside to the soldering iron tip, which has the advantages of fast heat, high heating efficiency, small volume, light weight and power consumption. It is suitable for welding small components. However, due to the high temperature of the soldering iron tip, it is easy to oxidize and blacken, the iron core is easy to be broken, and the power is small, only 20W, 35W, 50W and other specifications.
External thermal soldering iron definition
External heat means that the heat is generated outside because the heating resistor is outside the tip. It is suitable for welding large components and for soldering small components. There are 25W, 30W, 50W, 75W, 100W, 150W, 300W and so on.
The difference between internal heat type soldering iron and external heat type soldering iron
Structural aspect
First of all, there is a big difference in the structure of the soldering iron head. The internal heating type iron tip is hollow, because the heating core is built in, the external heating type iron tip is solid, and its heating core is external.
The external heating type soldering iron is composed of a soldering iron head, a soldering iron core, a casing, a wooden handle, a power lead, a plug and the like. Since the tip is mounted inside the iron core, it is called an external heating type soldering iron. The iron core is a key component of the soldering iron. It is formed by winding the heating wire in parallel on a hollow ceramic tube. The mica sheet in the middle is insulated, and two wires are connected to the 220V AC power supply. There are many specifications for external thermal soldering irons, such as 25W, 45W, 75W, 100W, etc. The higher the power, the higher the temperature of the soldering iron.
The internal heat type soldering iron is composed of a handle, a connecting rod, a spring clip, a soldering iron core and a soldering iron head. Since the iron core is installed inside the soldering iron tip, the heat is fast and the heat utilization rate is high, so it is called an internal heat type soldering iron. The common specifications of the internal heating type soldering iron are 20W and 50W. Due to its high thermal efficiency, the 20W internal thermal soldering iron is equivalent to an external thermal soldering iron of about 40W. The rear end of the internal heat type soldering iron is hollow, and is sleeved on the connecting rod and fixed by the spring clip. When the soldering iron head needs to be replaced, the spring clip must be first removed, and the front end of the soldering iron head is clamped with the pliers. Pull out slowly, remember not to use too much force to avoid damaging the connecting rod.
You can see it clearly from the soldering iron construction drawing. The external heating type heating core is separated from the soldering iron head by a heating tube in the middle.
Use aspect
The soldering iron head of the external heating type soldering iron is inside the heating core, and is also called an ordinary electric soldering iron. Soldering ordinary products, there is no requirement for temperature to use an external thermal soldering iron. Since the heating resistor wire is outside the soldering iron tip, most of the heat is radiated to the external space, so the heating efficiency is low and the heating speed is slow. It is generally necessary to preheat for 6 to 7 minutes to weld. Its large size makes it inconvenient to solder small devices. But it has the advantage that the tip is used for a long time and the power is large.
The internal heating type soldering iron, the shape of the iron head used for the internal heating type soldering iron is a hollow tube shape, and the heating element is covered by the soldering iron head, so that the heat thereof is not easily dissipated into the air, so the heat utilization efficiency is high, and the warming time is higher. Short, and the power is generally not too large to meet the requirements, the general internal thermal power is below 50W, common 20W ~ 30W internal heat type soldering iron. There are single handles and soldering stations. The 936 soldering station is a typical internal heat soldering iron, but it is also thermostatic. It is now a lead-free soldering iron (lead-free soldering station), which is better than the first two. 
Editor in charge: Zhao Hongli
Fan Light,Ceiling Fan Light,Led Ceiling Lamp Light,Led Ceiling Fan
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