How about the price of vacuum pneumatic butterfly valve? There are certain requirements for the selection and purchase of ball valve during the manufacturing of ball valve damper, which must comply with the following points:
1. The radius of the ball valve is 0.4 times of its height under rated load;
2. The ball valve shall have a certain additional stroke, at least equal to 50% of the rated static radius;
3. The number of ball valve coils shall not be too small, generally not less than six.
