PCBA Processing Soldering and False Soldering Problem analysis

A. What is False Soldering:

False soldering, that is, only a small amount of solder adhesion at the solder joints, occasionally flooded with open-circuit phenomenon, that is, poor contact between the components and pads, greatly reducing the reliability of the PCB multilayer board.

B. What is False Soldering:

False soldering is similar to false soldering, is the initial circuit works normally, later gradually open phenomenon.

C. Processes Involved

PCB multi-layer board welding, wiring, debugging.

D. False Ssoldering, False Soldering Hazards

Because of the existence of false welding, false welding greatly reduces the reliability of PCB multilayer boards and the overall product, to the production process causing unnecessary maintenance, increase production costs, reduce production efficiency, to the products have been shipped to cause a great deal of quality, safety hazards, and increase the cost of after-sales maintenance.

E. Welding Process Focus on Matters of Attention

Soldering iron: soldering iron head is clean, smooth without oxidation, if there is an oxidized layer needs to be soldered before the soldering iron head in the high temperature sponge wiped clean; soldering iron temperature control is within the range of requirements, the temperature is too high or too low will cause welding bad phenomenon, the general temperature control in the 300 degrees to 360 degrees or so, the soldering time of less than 5 seconds; according to the size of the different parts and soldering points, the device profile Select different power, type of soldering iron.

Solder wire: Selection of high-quality solder wire, (tin 63%, lead 37%) solder dosage should be appropriate, soldering point to solder wet pads, over the hole should also be wet filling shall prevail.

Other materials, tools: the accurate use of flux, in the use of welding auxiliary equipment to check whether the equipment is normal, in accordance with the instructions and attention to manipulate the manipulation. Maintain the equipment in time after use. (Semi-automatic tin dipping machine, crimping pliers, etc.)

Before soldering, check whether the device pins are oxidized or not, whether the wires, solder pads or transformer pins are oxidized or not. For oxidized devices need to remove the oxidized layer before welding, to prevent the presence of oxidized devices and lead to false soldering, false soldering. Welding materials and the environment should be clean to prevent the presence of stains, dust, resulting in poor welding.

Strictly implement the relevant technology provisions, fully utilize the production process of self-inspection, mutual inspection, the role of quality inspection, through some of the necessary tools, tooling to improve the maintenance of the pass rate.

Relevant parts of the targeted skills, knowledge training, to improve the staff's own manipulation skills; to explain to the staff of the hazards of the above topics, to improve the sense of responsibility of the production staff; to take the necessary documents to ensure the accuracy and reliability of the production.

Welding in the false welding, false welding is ultimately the staff responsibility and manipulation skills, should let the staff really form a product quality awareness, improve staff responsibility and strengthen the staff manipulation skills, from the device, tools, related systems and other aspects to improve the production, as far as possible to minimize and prevent false welding, false welding and other differences in the emergence of the topic.