Preparation before electric ball valve device
(1) The front and rear pipelines of the ball valve have been prepared. The front and rear pipes shall be coaxial, and the sealing surfaces of the two flanges shall be parallel. The pipeline shall be able to accept the weight of the ball valve, otherwise it is necessary to provide proper support on the pipeline.
(2) Purge the pipelines in front of and behind the valve, and remove the oil stain, welding slag and all other impurities in the pipeline.
(3) Check the mark of the ball valve and make sure the ball valve is intact. Fully open and close the valve several times to prove its normal operation.
(4) Remove the maintenance parts on the connecting flanges at both ends of the ball valve.
(5) Check the valve hole to remove possible dirt, and then clean the valve hole. Even if there are only fine particles between the valve seat and the ball, the sealing surface of the valve seat may be damaged.

Variable eccentric butterfly valve: The unique feature of variable eccentric butterfly valve is that the valve stem shaft for installing the butterfly plate is a three-stage axial structure. The two shaft sections of the three-stage axial valve stem are concentric, and the center line of the central section shaft deviates from the axis at both ends by a center distance. The butterfly plate is installed on the intermediate shaft section. Such eccentric structure makes the butterfly plate become double eccentric when it is in the fully open position, and become single eccentric when it is turned to the closed position. Due to the action of the eccentric shaft, when closing, the butterfly plate moves a distance to the sealing cone of the valve seat, and the butterfly plate matches the sealing surface of the valve seat to achieve reliable sealing performance.