A ball valve
The purpose of a ball valve is to regulate flow. They are most often used to regulate the flow of liquids, but they can also be used to regulate airflow. They operate by creating a situation where the substance is moving from an area of high pressure to an area of low pressure. They are all around us, in our plumbing, our cars, and our own bodies. The precursors to today’s, often quite complicated valves, were fairly simple. Early man did not have a lot with which to work, but he (or she) was observant, if nothing else. Beavers were able to divert the flow of water with sticks, leaves, and occasionally stones. Early man, observing this, began to do the same thing. By redirecting water, and then collecting it, they were able to create areas for washing, bathing, cooking, etc. Later, people began using a flap of either leather or wood, on a hinge. Water moving in one direction would cause the flap to open, but if it moved in the other direction, the flap would close. The first true man-made valve was born and thus, along with valve distributors. More products of valves
