There are some ball valves that permit only 90 degree rotation while there are others which can rotate 360 degrees as well. But you need to understand that it is necessary to have 90 degree rotation in order to close or open a ball valve. There is the handle that indicates the position of the valve ball. The valve is opened when the handle is found to be lying along the axis of the valve. There are also multiport ball valves that you can find in the market. When you observe the position of the groove you would be able to get to know the flow path through the ball. There is a ball inside the valve that has actually a hole at the middle. Liquid is flowed very easily when the hole is aligned with both valves.

More products of valves

Butterfly Valves

Globe Valves

Safety valves

Plug Valves

Reducing Valves