What are the basic principles for the choice of an electric soldering iron?
Only by choosing a suitable soldering iron can we ensure the smooth progress of the welding work. Here is a summary of the general principles when choosing a soldering iron, as well as the power principles to consider when choosing a soldering iron. Let's take a look.
General principles for choosing a soldering iron
1. The shape of the soldering iron tip can adapt to the surface requirements of the parts to be welded and the assembly density of the product.
2. The temperature of the tip of the soldering iron tip needs to be compatible with the melting point of the solder, which generally needs to be 30-80°C higher than the melting point of the solder (excluding the temperature that drops when the soldering iron tip contacts the soldering point).
3. The heat capacity of the electric soldering iron must be appropriate, and the temperature recovery time of the soldering iron tip needs to be adapted to the requirements of the surface of the object to be welded.
Temperature recovery time refers to the time required for the tip temperature to return to the maximum temperature after it has dropped due to heat loss during the welding cycle. It is related to the power and heat capacity of the electric soldering iron and the shape and length of the soldering iron tip.
Principles for choosing the power of a soldering iron
1. When soldering integrated circuits, transistors and other components that are susceptible to heat, consider using a 20W internal heating or 25W external heating soldering iron.
2. When welding thicker wires and coaxial cables, consider using a 50W internal heating or 45-75W external heating soldering iron.
3. When welding larger components, such as metal chassis grounding lug, you should choose a soldering iron with a power rating of 100W or above.
Summarize:
The larger the soldering iron tip, the greater the heat capacity. When performing continuous welding, the larger the soldering iron tip, the smaller the temperature drop.
The large soldering iron tip has a high heat capacity and can be used at a lower temperature when welding. The soldering iron tip is not easily oxidized and can extend the service life of the soldering iron tip.
A soldering iron tip has a contact area with the solder joint. The large contact area can produce effective heat transfer. The size of the soldering iron tip is based on the standard that it does not affect adjacent components. Choosing geometric dimensions that can fully contact the solder joints can improve welding efficiency.
There are various shapes of soldering iron tips, and the key points for selection are: always maintain a certain amount of solder, melt the solder on the joint quickly and effectively, without causing false soldering, soldering, or hanging tin, have no burrs in the solder joints, and will not burn the board and components.
