----In this case analysis, we mainly analyzed the problems of the aerosol valve on the curing agent side of the 2K aerosol tin can and provided corresponding solutions.

We sent some samples of 2K aerosol tin cans to the client for testing, The client reported that the button of the short-stem valve did not spring back after being pressed. Based on this issue, our technical department has provided the following feedback.

(Reason)

Because there is a thimble inside the valve, after the button is pressed, the thimble does not return, so the button does not bounce back. And the main reason why the thimble does not rebound is that some curing agents with low solid content / high water content react with the spring in it. Therefore, it become a hard block, and the spring was trapped. Make the spring lose its elasticity, force the valve core out. After our long term test, we found that low solid curing agents especially those below 30 solids, will let the valve cannot rebound. 

(Solution)

This is the first generation valve, it will indeed happen to the first generation valve if a low solid curing agent is added. High solid (curing agent close to 45), basically dose not have this problem

--The first generation valve--

So for the second improvement, we prevent the curing agent from entering the valve chamber, avoid reacting with spring. We modified the stem to act like a piston, blocking the spool directly so that the curing agent can't seep through. There's also a kind of piston ring that's make here to seal the valve chamber, to reduce the amount of curing agent that can get in and from a hard lump. Because this screw has spiral loops inside it. The low solid curing agent seeps in and react with the spring.

--The second generation valve--

The construction of the third generation valve, we put an end to the outside air, that is, do not let it spray out, and directly turn the inside valve core into a solid rod (previously it was a hollow rod).

--Update iteration of valve--