A brief discussion on the technical operation norms and precautions of the wave soldering process for solder rods

Wave soldering is toPCBThe soldering surface of the circuit board's soldering circuit board directly contacts the high-temperature liquid tin, thereby achieving the purpose of the soldering technology requirements, keeping the high-temperature liquid tin at an inclined plane. The liquid tin is formed into a similar wave by a special device, mainly bySolder rodMade. After all, the entire process is almost entirely completed by machines. Therefore, the operation method of wave soldering technology is the fundamental reason that directly affects the soldering technical requirements of electronic products. Or for electronic products with lead-free requirements, the operation method of wave soldering technology is relatively strict. Next, the solder paste manufacturer will communicate with everyone about the technical operation norms and precautions of the wave soldering process for solder bars.

1. The inclination of the wave soldering trajectory

The slope of the trajectory has a relatively obvious impact on the requirements of welding technology, especially for welding technology which requires high densitySMTThis is especially true when it comes to devices. If the inclination is too small, it is very easy for bridging to occur, especially in the welding technical requirements.SMTThe covered area of the device is extremely prone to bridging situations. However, if the inclination is relatively large, although it will reduce the probability of bridging situations occurring, the amount of tin absorbed by the solder spot will decrease, and it is prone to false soldering. Therefore, everyone must adjust the slope of the trajectory to5~7℃Between each other.

Ii. The amount of flux applied

To further enhance the technical requirements for welding, we mustPCBA very thin layer of flux should be applied to the bottom of the circuit board. It needs to be evenly rubbed and not too thick, especially for some products that require a no-clean processing technology.

Iii. Electronic ProductspcbThe preheating temperature of the circuit board

pcbPreheating the circuit board in advance is to better ensure that the solvent in the pre-applied flux fully evaporates during the soldering process and continuously improvespcbThe moisture content of circuit boards and the formation efficiency of solder joints; Meanwhile, preheating in advance will also makePCBThe temperature of the circuit board rises steadily and gradually reaches the required temperature to preventpcbThe circuit board was directly subjected to thermal shock and warped and deformed. Generally speaking, the preheating temperature is controlled at180~200℃The preheating period is1~3More than a minute.

Iv. Welding Temperature inside the wave soldering furnace

Welding temperature is a relatively important factor affecting the technical requirements of welding. A lower soldering temperature can significantly reduce the ductility and wetting performance of the solder, which may prevent the solder pads or the soldering ends of electronic components from being fully wetted, easily leading to soldering problems such as false soldering, sharp edges, and bridging. Excessively high soldering temperatures will accelerate the oxidation of solder pads, electronic components and solder rods, which can easily lead to poor soldering technical requirements. Therefore, everyone can refer to the solder andpcbCircuit boards are all different. It is necessary to control the soldering temperature well.

V. Wave peak Angle of Wave Soldering

Due to the passage of welding work time, the height of the peak may change. We should make appropriate modifications during the welding process to ensure that the welding process is carried out at the appropriate peak Angle. The peak Angle is determined by the depth of tin pressingPCBPlate thickness1/2~1/3As the standard.