Occasionally, when using a wave soldering furnace for welding, there will be unmelted tin slag in the form of bean curd residue inside the furnace. What should we do in this situation? Today, the solder paste manufacturer will share with you how to deal with the incompletely melted tin slag in the tin furnace.

Problems with tin slag in the form of tofu residue and their solutions

First, it is necessary to analyze and test the problems with the tin slag to facilitate targeted treatment.

I. Objective reasons of the equipment

The operating temperature of the equipment: The temperature of the wave soldering was not adjusted very high. During the soldering process, the operating temperature of the machine did not meet the standard, which caused the solder to fail to melt.

Solution: The preheating working temperature is generally at the bare board80-120℃,With a fixture100-180℃During this period of time; The temperature of the tin furnace is on the lead-free bare plate260-265℃Lead-free tape fixtures265-275℃There is lead.6337Bare board245-255℃Bring fixtures250-260℃There is lead.55°Tin bar255-275℃Bring fixtures260-280℃During that period of time.

The height of the wave crest: When the wave is so high, the working temperature of the solder drops more significantly when it falls. The solder mixes with the air and rushes into the tin furnace, causing oxidation and semi-dissolution, which is the reason for the formation of tin slag.

Solution: The frequency of the peak frequency converter should be kept as low as possible20HZOr the height of the wave peak tin spraying does not exceed10mmThis can greatly reduce the air flow rate of the tin at the peak nozzle.

Machine maintenance: The furnace was not cleaned immediately, and the fallen solder did not quickly enter the furnace. Some of the solder remained on the solder dross, causing uneven heating of the solder.

Solution: Once there is a lot of tin slag on the tin surface, it must be cleaned up immediately to prevent the tin sprayed out by the wave crests from falling onto the remaining hard block tin slag and being difficult to fall back into the tin liquid, solidifying into the tin slag and forming a curd-like tin that does not melt.

Ii. Objective reasons of solder materials

Regarding the tin bars: It is possible that the quality of the raw materials of the tin bars is substandard due to the reduction to tin or the doping and recycling treatment for the reduction to tin.

Solution: Choose the brand of the enterprise when making a purchaseTin barIt is absolutely not advisable to save some expenses to purchase tin bars from small workshops.

In terms of flux: When too much flux is added, the remaining flux will fall back into the tin furnace during the peak period of the tin furnace.

Solution: Pay more attention to the application of flux and carry out the application based on the prerequisite conditions required by the actual situation.