Valve

device that regulates, directs or controls the flow of a fluid or a gas

A valve is a device that it is used to decrease or stop the flow of a fluid (like gases, liquids, fluidized solids, or slurries). It can be installed for example in a pipe or a vessel.

These water valves are operated by handles.

There are many types of valves. Some examples are:

They can be operated manually or automatically.

change

Other websites

change
  NODES
Note 1