Vacuum pumps are mechanical devices that reduce the pressure within a container by removing gas molecules from inside the container. Vacuum pumps are divided into two general categories: positive displacement pumps and momentum transfer pumps.
Positive displacement pumps reduce the pressure within the container by creating an area of low pressure inside the tank. As the air molecules attempt to flow into this low pressure area, they are pushed out of the container by a piston, diaphragm, or some other mechanical device. This type of vacuum pump is typically used in industrial applications that require consistent and steady vacuum levels.
Momentum transfer pumps, on the other hand, work by transferring energy from the gas molecules to the walls of the container. This type of vacuum pump is typically used in laboratory or scientific settings. The most common example of a momentum transfer vacuum pump is the turbomolecular pump. Turbomolecular pumps use a series of rotating blades to transfer energy from the gas molecules to the walls of the container. In this way, the molecules within the container are accelerated in a controlled fashion, which leads to a reduction in pressure.
Vacuum pumps are also classified according to their overall efficiency. There are two types of vacuum pumps: rotary vane pumps and claw pumps. Rotary pumps use a series of vanes to create a vacuum. The vanes spin in a rotor, and this action creates a vacuum. Claw pumps, on the other hand, use a series of “claws” to capture and move the molecules within the container. The claws move the molecules towards the walls of the container, which leads to a reduction in pressure.
Finally, vacuum pumps can also be divided into dry pumps and wet pumps. Dry pumps use simple mechanical systems, such as dust seals and filters, to reduce the pressure within the container. Wet pumps use liquids to reduce the pressure within the container. These liquids, such as water, are used to fill up the container so that the gas molecules within the container are inundated with liquid molecules, which reduces the overall pressure.
In conclusion, vacuum pumps are divided into a myriad of categories according to their overall application and efficiency. Positive displacement pumps, momentum transfer pumps, rotary pumps, claw pumps, dry pumps, and wet pumps are all types of vacuum pumps. These pumps are essential tools used in a wide variety of applications, including industrial, laboratory, and scientific settings.
