Mechanical Seal: Mechanical seals are leakage control devices that can be found on rotating equipment like pumps and mixers. They are used to avoid any leakage of liquids and gases into the natural environment. It works on 2 principle components; one is stationary and the other one rotates. There are different types of mechanical seals from simple spring designs to complex cartridge seal types. Dynamic Seal This is best described as one where there is a shift between a hardware constituent and sealing component. The motion can be reciprocating, oscillatory and even rotary. This seal is required to prevent any leakage in the parts which are in relative motion. The seal holds or separates fluids keeping out contaminants and pressure.