Regarding Radicon requested for quotation, I went to follow up their quotation and spring samples. The customer informed me about the test result as belows:
After they had tested samples of springs, the test result of Negative Pressure Valve Spring is "OK".
For the test result of positive spring Ø0.25 was so far from their customer spec. This positive spring is required to increase its spring constant.
Their 1st step is to increase wire diameter from 0.25 to 0.3. If its result is still so far from their customer spec, their next step may reduce the number of active coils.