Common problems and solutions for dispensing valves
Release Date：2017-06-22
Common problems and solutions for dispensing valves
1. Leakage of rubber valve This situation often occurs after the pre glue valve is closed, and 95% of it is due to the small diameter 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 when the rubber valve is first used. Solution: The pressure of the pressure bucket can be adjusted, not too high, and it can drive the glue. If the dispensing valve can be fine tuned, try to adjust it as small as possible (to reduce the quick response time of the dispensing valve), or replace the larger needle to solve this problem. The conical inclined needle produces the least back pressure and the smoothest liquid flow. The air inside the liquid will drip after the rubber valve is closed. It is best to eliminate the air inside the liquid in advance or use a rubber that is less likely to contain bubbles. Or centrifuge the glue to remove bubbles before use. 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. Solution: The intake pressure regulator should be set at 10 to 15 psi lower than the minimum pressure in the factory. The pressure used for the pressure cylinder should be above the pressure in the middle of the pressure gauge, and the use of pressure in the low pressure part of the pressure gauge should be avoided. 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 in the fluid Excessive fluid pressure combined with too short valve opening time may allow air to seep into the liquid. Solution: Reduce fluid pressure and use a conical angled 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. Solution: Ensure the use of fresh instant glue. Thoroughly clean the pipeline with acetone free of moisture, ensure that the air used is dry, and install a filter between the air pressure and rubber valve system in the factory. If the above methods are still ineffective, nitrogen should be used
