8/9/2023 0 Comments Soldering iron for ona holes![]() ![]() ![]() In the case of insufficient preheating, thermal stress caused by sudden heat during soldering may cause damage to some components.Īs mentioned above, the critical control points for this process are preheating temperature and preheating time. Reduce the thermal stress produced during soldering Insufficient preheating may cause the liquid solvent in the flux to vaporize violently when it reaches the peak of the wave, resulting in solder spatter and tin slag Excessive preheating will cause the active ingredients of the flux to evaporate prematurely and lose the wetting effect, resulting in bridging or pointing during soldering. ![]() The functions of preheating mainly include: Now the general use of spray system for flux spraying, the process of the need to focus on control is the amount of coating and uniformity, that is, the requirement of uniform coating, and the amount of flux coating is moderate.Insufficient or uneven flux coating may result in insufficient activation of pads, resulting in missed and poor soldering. Reduce the surface tension of liquid solder, improve the diffusion ability.Prevent the re-oxidation of metal surface.Clean the oxide that may exist on the surface of PCBA boards which waiting solderinrg.At same time, whether the fixture is cleaned regularly also needs attention. ![]() The clamping fixture installed on the PCB to be soldered can limit the degree of thermal deformation of the substrate and prevent the occurrence of soldering phenomenon, so as to ensure the stability of the soldering effect, which is particularly important for the thinner PCB.If the splashed tin residue is often left on the PCB during wave soldering, it can be considered to add a protective cover on the fixture. In the process of wave soldering, more attention should be paid to the degree of thermal deformation control. Wave soldering requires high flatness of PCB board, and the thickness of PCB board of automotive electrical components is generally only 1.6mm, so the warpage requirement itself is very high. The process of wave soldering, mainly can be divided into these several stages: install fixture, flux coating, preheating (temperature 90-100℃, length 1-1.2m), soldering and cooling. Wave soldering is to make the soldering surface of the plug-in PCBA circuit board directly contact with the high temperature liquid tin to achieve the purpose of soldering, the high temperature liquid tin to maintain a bevel, and by the special device to form a similar wave of liquid tin phenomenon, so called “wave soldering”.īelow is a schematic diagram showing the wave of molten solder paste passing through the bottom surface of the board, making the PCB pad and the component pins fully soldered and firmly connected. Is mainly used for through-hole components and SMD components soldering of SMD adhesive (red glue) process, in the latter case, before through the molten solder furnace, through the SMT placement machine, the components and adhesive bonded on the surface of the printed circuit board (PCB). It is called wave soldering because it uses wave-like soldering. Wave soldering is used to make assembled printed circuit boards in a batch PCBA fabrication. Wave soldering is a soldering process that the molten liquid solder, with the help of a pump, forms a specific soldering wave on the surface of the solder tank, and the PCB with the components is placed on the transmission chain, the soldering joint is realized by passing through at a specific angle and a certain immersion depth. Technical requirements for high quality control of wave solderingDIP wave soldering overview ![]()
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