Spray dispensing is widely used in dispensing automation process, such as underfill, encapsulation, hot melt adhesive and so on. It is also because in such a variety of dispensing processes, there are often some problems in process control, For example: bubble, scatter point and glue change So, let's talk about the influence of bubbles on our dispensing process? Where do bubbles come from? How to avoid it effectively? Next, I will analyze and explain.
01 Effect of bubbles
So it is certain that bubbles are not what we want to see and should be avoided.
02 What are the causes of bubbles,
How to judge?
Generally speaking, bubble causes can be divided into internal and external reasons. The internal is the cause of the glue itself, and the external is the cause of the sizing process
Interior: The reason of glue itself is whether the transportation, storage, return temperature and use of glue follow the normal process
External: The external causes of bubbles mainly lie in the control of sizing process.
There are so many reasons for bubbles. How should we analyze and investigate them?
03 And how to lock in the causes?
To quickly check and lock the cause, it is generally necessary to start from The big influence factor begins Further analysis To the small segments of the Such as: glue, valve, product, environment four big factors to analyze, and then subdivide each big factor has which small factor causes, the analysis step we may refer to the doctor diagnosis patient's method, Look, smell, ask, cut, Find out the real cause.
Just look. What are you looking at? Components related to rubber path What are the phenomena of bubbles at every point? Or is it just the first point? Number and size of bubbles? Is there a rule? Is there any bubble in the glue itself? It is also the bubble generated after passing through the valve body, whether the glue label is expired, whether the needle cylinder can see the bubble, whether the piston is separated from the glue, and so on. Summarize the phenomenon you can see on the surface.
It's listening, Listen to the sound of each part For example, when the injection valve is ejecting, whether the impact sound is clear, clean and not muddy. If there is a dull sound, it may be necessary to analyze whether it is the solenoid valve or other moving parts; in addition, listen to the feedback from customers or technical support on the problems, and what are the phenomena.
Whether the bubbles are regular or not, When did it happen, in the morning, at noon, at night, in the morning? After changing the glue? By using the 5W1H analysis tool, you can roughly know where the problem occurs.
namely Verification test analysis, debugging parameters, replacement configuration, cleaning components and other methods to verify The most commonly used method is to replace a new glue to see if there is improvement; parameter adjustment, adjust the parameters affecting the bubble, reduce the impact force, etc., to see whether the effect is effective; to replace the nozzle, impact pin, seal ring, etc., so that the number of spray can be reduced, and the required amount of glue can be achieved; whether the valve body is in normal working state, whether there is a phenomenon of unsmooth action, if there is, it must be entered If it can be replaced, instead of just being able to use it, there will be a risk of bubbles; of course, from a microscopic analysis, we can use a similar high-speed camera to shoot slowly, and analyze the phenomenon that is difficult to observe with the naked eye
To get it A stable no bubble dispensing effect, routine inspection, maintenance of course can not be missing The stability of quality can be guaranteed only if all parts work normally.
The above is the whole content of this issue of Huang Sir lecture. We will encounter a variety of process problems in the dispensing process. You can also interact with us through the message area at the bottom. If you want to know about the dispensing technology topic, you can also tell us in the bottom message area, maybe the next issue is the topic you are looking forward to!
SHENZHEN AXXONAUTOMATION CO., LTD.
Shenzhen axis automatic control technology Co., Ltd
Building A14, silicon valley power automotive electronics Pioneer Park, 334 Guiyue Road, Guanlan, Longhua District, Shenzhen, China
Tel ：+86 755 8358 6066
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