There are typically three types of for example dry valve pumps
The hydraulic pump is the element of the hydraulic system that takes mechanical energy and converts it into fluid energy in the form of oil flow. This mechanical energy is usually taken from what’s called the prime mover (a turning drive) like the power take-off or straight from the truck engine.
With each hydraulic pump, the pump will be of the uni-rotational or bi-rotational design. As its name implies, a uni-rotational pump is made to operate in one path of shaft rotation. On the other hand, a bi-rotational pump has the ability to operate in either direction.