Common issues with high-speed spray valve gluing
Process control during the dispensing process: The following process defects are prone to occur during production: inadequate size of adhesive points, wire drawing, adhesive immersion on solder pads, poor curing strength, and easy peeling. Therefore, controlling the technical process parameters of dispensing is the solution to the problem.
The size of the dispensing amount: Based on work experience, the diameter of the dispensing point should be half of the distance between the solder pads, and the diameter of the dispensing point after SMT should be 1.5 times the diameter of the dispensing point.
Glue dispensing pressure: The pressure should be selected based on the same quality of glue and the working environment temperature. A high ambient temperature will reduce the viscosity and improve the fluidity of the adhesive. In this case, it is necessary to lower the pressure to ensure the supply of adhesive, and vice versa.
Size of dispensing nozzle: The same type of needle can be selected, but for pads with significant differences, different dispensing nozzles should be selected to ensure the quality of the dispensing points and improve production efficiency.
The viscosity of glue: The viscosity of glue directly affects the quality of dispensing. If the viscosity is high, the adhesive point will decrease, and even wire drawing may occur; When the viscosity is low, the adhesive point will increase, which may lead to infiltration of solder pads. During the dispensing process, choose a reasonable pressure and dispensing speed for adhesives with different viscosities.
Bubbles: Glue must not have bubbles. A small bubble can cause many solder pads to lack glue; Every time the glue is filled, the air in the glue bottle should be emptied to prevent empty tapping.
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