Differences between Internal-heated and External-heated Electric Soldering Irons
The heating wire of an internally heated soldering iron is wrapped around a ceramic rod and insulated with a ceramic tube. When in use, the soldering iron tip is placed outside the ceramic tube, and heat is transferred from the inside to the outside soldering iron tip, which is called an internally heated soldering iron. External heating soldering iron is exactly the opposite. The heating wire is wound around an iron tube with a hole in the middle, insulated with mica sheets inside and outside, and the soldering iron tip is inserted into the middle hole. The heat is transferred from the outside to the soldering iron tip inside, which is called external heating type.
1. Different appearance
External heating soldering iron has a larger accumulation, while internal heating soldering iron has a relatively smaller accumulation
2. Different structures
The internal heating element is located inside the copper head, while the external heating wire is located outside the copper head.
3. The soldering iron tip is different
The internal heating type soldering iron tip is hollow because the heating element is built-in, while the external heating type soldering iron tip is solid and its heating element is external.
The shape of the soldering iron tip is hollow cylindrical for internal heating and solid rod-shaped for external heating;
4. Different heating elements
The internal heating type uses a ceramic heating core, with the heating wire wrapped around a ceramic rod and insulated with a ceramic tube. The external heating type soldering iron uses a conventional mica heating wire for heating, with the heating wire wrapped around an iron tube with a hole in the middle and insulated with mica sheets inside and outside.
5. Different heating efficiencies
External heating electric soldering iron has low heating efficiency, slow heating speed, and slightly longer preheating time due to the fact that the heating resistance wire is located outside the soldering iron tip, and most of the heat is dissipated to the external space. The internal heating type has a faster temperature rise, higher heating efficiency, and utilization rate about twice as high as the external heating type. The preheating time is shorter, but it is slightly affected by temperature, especially for low-power types;
6. Different power levels
External heating soldering iron has a high power output, with different specifications ranging from 25W to 300W; Internal heating soldering irons are usually small in capacity, with various specifications such as 30w-100w.
7. Different uses
External heating soldering iron is commonly used for welding large objects and is not suitable for welding small components.
8. The service life varies
External heating soldering iron has a long service life; Internal heating soldering iron has a short service life.
