Replacing Single Mechanical Seal in the PD300 – 575 Series Pumps

A single mechanical seal consists of two flat seal faces, amalgamated together by a spring while sliding against one another. A film is produced between the two seal faces from the process fluid/lubricant cooling the seal’s internals, creating a protective barrier. An absence of the film results in frictional heat and ultimately, the breakdown of the mechanical seal. To keep your single mechanical seal operating properly, ensure that: • the seal is receiving the proper quality and quantity of lubricating oil • there is no debris being introduced to the sealing faces • the sealing faces and/or O-rings aren’t damaged during installation This step-by-step video demonstrates how to replace single mechanical seals for the Unibloc Pump PD300 – 575 series of sanitary positive displacement pumps. A single mechanical seal is typically used when the process fluid that is pumped presents little to no risk to the environment.