What is the ideal installation position of the rotary exhaust valve?

When installing the rotary valve, the level of the installation of the valve stem is an ideal position, this can prevent the pipe below the sediment into the bearing. Due to close the valve when the fluid solid particles deposited. Therefore, ball valve and butterfly valve opening direction to help displaced the solid, that is to say, when the butterfly valve plate and the ball core rotation should be from the bottom to the top of the rotation. Rotary valve also installed in the space position and convenient maintenance.