Several factors affecting the dispensing effect

The following are several factors that affect the dispensing effect:

1. The dispensing amount is generally controlled by the dispensing time, and the longer the time, the larger the dispensing amount. It is generally appropriate to control the diameter of the adhesive dots at half of the product spacing, which can avoid excessive glue and ensure sufficient glue to bond the product components. Different adhesives with different viscosities can also affect the amount of glue produced, so in practical applications, corresponding adjustments need to be made according to the actual situation and the appropriate dispensing time needs to be selected.

2. The gas supply pressure and operating speed are high, and the glue flows quickly, making it easy for excessive glue to overflow. When the air pressure is low, the flow rate of glue is slow, and the amount of glue is easily insufficient, resulting in intermittent dispensing or leakage points. On the other hand, the running speed is the opposite. If the speed is too slow, it is easy to have too much glue, and if the running speed is too fast, it is easy to have interruptions or leaks. Therefore, it is very important to adjust the operating speed according to different air pressures, and these adjustments should be made according to the actual situation in the application process.

3. The needle of a needle dispensing machine usually needs to select a needle with an inner diameter of about half the diameter of the dispensing point. During the dispensing process, the dispensing needle should be selected according to the size of the product.

At the same time, different adhesives have different requirements for the needle. Instant glue: For water-based instant glue, use a safe piston and Teflon lined metal needle. For thick instant glue, use a conical inclined needle. If flexibility is required, use a PP needle; UV glue: Use amber syringe, white piston, and angled needle (can block UV rays). If other types of needles are used, please customize a needle that can block UV rays; UV curable adhesive: Use a black opaque syringe to avoid exposure to light; Anaerobic adhesive: using a 10CC syringe and a white PE universal piston; Sealing glue and paste like fluid: If the white piston rebounds severely, please use a safe movable type and an inclined needle.

4. The distance between the needle and the working surface varies for different adhesives, products, and dispensing machines. Some needles have a certain degree of stopping, so it is important to control the dispensing distance. Therefore, it is necessary to calibrate the distance between the needle and the working surface before each work.

5. In addition to the factors related to the glue itself, the viscosity of the glue also directly affects the quality of the glue. If the viscosity is high, the glue point will be small, and if the viscosity is low, the glue point will be large. If the viscosity is too high, it may even cause wire drawing, and if the viscosity is too low, it may infiltrate the product. At the same time, the environment also has a significant impact on glue. Generally, the temperature of glue should be between 23 ℃ and 25 ℃,. If the temperature is too low, the viscosity of the glue increases, otherwise the viscosity decreases. The manufacturer has provided the temperature curve for adhesive curing, and in practice, higher temperatures should be used as much as possible to cure the adhesive, so that it has sufficient strength after curing.

6. Bubble glue must be absolutely guaranteed to have no bubbles, as a small bubble can lead to defective products or many products without glue. Therefore, every time the hose is replaced, it is necessary to empty the air at the connection to prevent the occurrence of empty play.