Dropping of dispensing needle is that when the valve closes, the dispensing needle begins to overflow glue partially. This situation is mainly caused by the small diameter of the needle used. The small needle will affect the flow of liquid. The problem of needle dropping directly leads to back pressure, which leads to leakage soon after the valve closes. When the valve is in use, too small a needle will also affect the bubble movement. This can be solved by replacing larger needles. In the distribution needle, the conical oblique needle produces a low back pressure, and the liquid flow is smooth. The use of this needle is one of the solutions to drip hanging.
Needle drip hanging means that after the rubber valve closes, there will still be glue overflow on the dispensing needle and drip out.
Liquid containing air or bubbles is also one of the reasons for dropping. Therefore, it is also an effective solution to remove the air in the liquid in advance, or to use the glue which is not easy to contain bubbles, or to use the gel before defoaming.
Multi-tube stainless steel dispensing needle