Electronic soldering technology Precautions for manual soldering of circuit boards

Date：2022-12-07 16:29:14Views：598

In the production of electronic products in the electronic industry, the joints of components need to be welded with solder wire, and the quality of welding has a great impact on the quality of production. In order to ensure a better application effect, the tin wire is usually welded manually later. In order to enhance your understanding of the manual soldering of circuit boards, the following is a small compilation of electronic soldering technology related content, hoping to give you reference and help.

1、 For the soldering of electronic products, you must first choose a good soldering tool. Common manual soldering tools include electric soldering iron. For example, we use a 20W internally heated electric soldering iron. Before using a new soldering iron, use fine sandpaper to coat the soldering iron wire with tin evenly. In this way, it is easy to weld and prevent the surface oxidation of the soldering head. If the old soldering iron head is seriously oxidized and blackened, the surface oxide can be removed by steel filings to make it show metallic luster, and then it can be used after being tinned again.

2、 The electric soldering iron shall use 220V AC power supply, and special attention shall be paid to safety during use. The following points should be carefully done: it is better to use a three pole plug for the electric soldering iron plug, and the shell should be properly grounded; Before use, carefully check the power plug and power cord for damage. Check whether the soldering iron head is loose

3、 The electric soldering iron shall not be knocked hard during use. Prevent falling. If there is too much tin on the soldering iron head, it can be wiped off with a cloth. Do not throw it randomly to avoid scalding others.

4、 The soldering iron shall not be placed everywhere during the welding process of the solder wire. When the tin wire is not soldered, it should be placed on the soldering iron frame. Note that the power cord shall not be laid on the soldering iron head to prevent accidents caused by burning the insulation layer.

5、 After use, cut off the power supply in time and unplug the power plug. After cooling, take the electric soldering iron back into the tool box.

6、 When soldering electronic components with solder wire, it is now generally used to solder wire with rosin core. This solder wire has a low melting point and contains rosin flux, which is very convenient to use. Before welding, the welding parts of component pins or circuit boards shall be treated before welding, the oxide layer on the welding parts shall be removed, and the sawblade can be used to make a knife. Scrape off the oxide layer on the surface of the metal lead to expose the metallic luster of the pin.

7、 After the pre welding treatment is completed, the formal welding can be carried out. The correct welding method is to hold the electric iron in the right hand and clamp the components or wires in the left hand with pointed nose pliers or tweezers. Before welding, the electric soldering iron shall be fully preheated, and the blade of the soldering iron head shall be provided with a certain amount of tin. Close the blade of the soldering iron head to the welding spot. The angle between the electric soldering iron and the horizontal plane is about 60 ℃. To facilitate the molten tin to flow from the soldering iron head to the solder joint. The dwell time of the soldering iron head at the solder joint shall be controlled within 2-3 seconds. Lift the soldering iron head. The left hand still holds the element. The left hand can only be released after the tin at the solder joint has cooled and solidified.

8、 The quality of welding must ensure that each welding point is firmly welded, well contacted, bright, smooth and burr free, and the amount of tin is moderate. The tin and the soldered object are firmly fused. There should be no false soldering and false soldering. If there is a false soldering, there is only a small amount of tin at the solder joint, resulting in poor contact, which is always on and off; False soldering refers to the phenomenon that the surface seems to be welded, but it is not actually welded. Sometimes, the lead can be pulled out from the solder joint by hand. These two situations will bring great difficulties to the debugging and maintenance of electronic production. Only after a lot of careful welding practice can these two situations be avoided. Therefore, when welding circuit boards and electronic components, we must control the time to be neither too long nor too short. It is best to just fit it, so that the components and boards can be firmly welded without dragging.

Generally speaking, manual welding is a traditional welding method. Although manual welding is rarely used in the production of large electronic equipment, it is inevitable to use manual welding in the maintenance and adjustment of electronic equipment. At the same time, the welding quality will also damage the maintenance effect. As a professional skill with strong theory, manual welding requires more practice to ensure excellent welding quality. This article hopes to be helpful to you. Our company has professional engineers and industry elite teams, and has built three standardized laboratories with an area of more than 1800 square meters, which can undertake a variety of test projects such as electronic component test verification, IC authenticity identification, product design material selection, failure analysis, function testing, factory incoming material inspection and tape weaving.