Introduction to the selection and use of electric soldering iron
Selection of electric soldering iron
It can be seen from the previous speed that there are many types and specifications of electric soldering irons, and the sizes of the workpieces to be welded are different. Therefore, the rational selection of the power and type of electric soldering irons has a direct relationship with improving welding quality and efficiency. If the welding is too large and the power of the electric soldering iron used is small, the welding temperature is too low, the solder will melt slowly, the flux cannot volatilize, and the solder joints will not be smooth and firm. This will inevitably lead to unqualified welding strength and appearance quality, and even the solder cannot Melted, making welding impossible.
If the power of the electric soldering iron is too high, too much heat will be transferred to the tool to be welded, and the solder joints of the components will be overheated, causing damage to the components, or causing the copper foil of the printed circuit board to fall off, and the solder will be on the soldering surface. The flow was too fast to be controlled.
The correct selection of electric soldering iron can be considered from the following aspects:
1) When soldering integrated circuits, transistors and vulnerable components due to heat, a 20-watt internal heating type or a 25-watt external heating type electric soldering iron should be used.
2) When welding wires and coaxial cables, a 45-75 watt external heating soldering iron or a 50 watt internal heating soldering iron should be used.
3) When soldering larger components, such as the lead pins of output transformers, the lead pins of large electrolytic capacitors, the grounding pads of metal chassis, etc., an electric soldering iron of more than 100 watts should be used.
How to use a soldering iron
(1) How to hold the soldering iron
In order to make the weldment welded firmly without burning the surrounding components and wires, depending on the position and size of the welded piece and the size of the soldering iron, it is very important to properly select the grip of the soldering iron.
The grip of the soldering iron can be divided into three types,
Pen grip. This method is suitable for small-power electric soldering irons to weld parts with small heat dissipation, such as welding printed circuit boards of radios and TVs and their maintenance.
Forehand grip. The electric soldering iron used in this method is relatively large and mostly has a curved soldering iron tip.
The reverse grip method is to hold the handle of the soldering iron in the palm with five fingers. This method is suitable for high-power electric soldering iron welding parts with large heat dissipation.
