Lesson 12 - Control of Fluid Flow 3
This lesson will consider valve technology, which is used to control fluid flow. It will cover the control functions of on-off, and modulating flow control, together with a description of the various valve types which can achieve these functions. The lesson will conclude with thoughts on the issue of managing valve leakage to avoid cross-stream contamination.
Ball Valve
The ball valve is another type of quarter-turn valve, but instead of a circular disc, it utilises a ball-shaped element.
The ball has a through-hole in its body and is mounted on a spindle so that the orientation of the through-hole can allow flow to pass through it, or if aligned at right angles to the flow, the flow is blocked. It can be used as both a shut-off or a modulating control valve. The detail of the ball valve is shown in the figure below.
Figure: Ball valve
The ball valve takes its name from the ball within the valve itself.