Otherwise, the specification of the valve ball valve can be selected according to the nominal diameter of the pipeline. The pneumatic butterfly valve of the hanging ball valve is through the valve, the rigidity of the ball valve and the initial force of the ball valve pre compression to reduce or eliminate the periodic vibration or instantaneous impact caused by the irregular flow of the medium, wind force, water hammer (or steam hammer), earthquake and other reasons in the pipeline, It can increase the natural vibration frequency of the whole pipeline system and make it away from the forced vibration frequency of the pipeline caused by external interference, so as to avoid the phenomenon of pipeline co vibration and reduce the additional stress caused by the vibration of the pipeline