Positive displacement pumps work by trapping fluid on intake and displacing or forcing it upon discharge. This happens over and over and serves to move an exact amount of fluid for many different purposes. A commonly used positive displacement pump is the rotary design. Here is a closer look into this kind of pumping equipment.
Rotary design provides pumping of fluid with a rotating action. The act of rotation creates a vacuum that sucks in fluid. This same rotary action also dispels fluid upon discharge. There are advantages and disadvantages to rotary design.
Among the rotary advantages are its efficient pumping action. A lot of time and trouble can be avoided, as they do not require bleeding of air. The rotary action natural displaces air from the hydraulic system. This is important for maintaining pressure automatically.
There are a few drawbacks to rotary pumping equipment. This type of equipment requires close clearance of internal parts, in order to function. This means that the pumping action must be steady and slow. If operated at very high speeds, the equipment will eventually fail, as wear will increase clearance among the parts. Faster speeds will also decrease the pumping efficiency.
A gear pump works with gears that mesh together, and is one of the most popular types of pumping equipment used today. Some equipment employs internal gears while others have external gears. The industrial gear pump can be used for pumping fluid or as a motor.
Other kinds of designs include screw and rotary vane pumps. The screw design is very simple and displaces fluid like a screw conveyor. Rotary vane equipment utilizes a cylindrical rotor that captures fluid within its vanes as it turns. These are only a few of the many kinds of positive displacement pumps that are used in today’s industry.