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Common faults and solutions of dispensing valves

Release Date:2017-07-30
Common faults and solutions of dispensing valves

1. Dripping occurs after the dispensing valve is closed.

This situation is mostly caused by the small caliber of the needle used. A needle that is too small can affect the flow of liquid and cause back pressure, resulting in dripping shortly after the rubber valve is closed. A too small needle can also affect the exhaust bubble action of the rubber valve when it is first used, and this problem can be solved by replacing it with a larger needle.
2. Inconsistent adhesive size.
When the dispensing is inconsistent, it is mainly due to the unstable pressure of the pressure cylinder or air storing the fluid. The intake pressure regulator should be set at a pressure 10 to 15 psi lower than the minimum pressure in the factory. The pressure used by the pressure cylinder should be above the middle pressure of the regulator, and it should be avoided to use a pressure between the low pressure part of the pressure gauge. The control pressure of the glue valve should be at least 60psi to ensure stable glue dispensing. Finally, the glue dispensing time should be checked. If it is less than 15/1000 seconds, it will cause unstable glue dispensing. The longer the glue dispensing time, the more stable the glue dispensing.
3. The flow rate is too slow.
If the flow rate is too slow, the pipeline should be changed from 1/4 "to 3/8". If there is no need, the pipeline should be as short as possible.
4. Bubbles inside the fluid.
If the fluid pressure is too high and the valve opening time is too short, air may seep into the liquid. The solution is to reduce the fluid pressure and use a conical inclined needle.
5. Instant glue (quick drying glue) blocks the glue valve joint and pipeline.
This situation is mainly due to excessive moisture or repeated use of instant glue. It should be ensured to use fresh instant glue, thoroughly clean the pipeline with acetone that does not contain moisture, and ensure that the air used is completely dry. A filter should be installed between the air pressure and the glue valve system in the factory. If the above methods are still ineffective, nitrogen should be used
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