Sealing has come a long way from the tribal days of packing. With advancing technology comes new ways in sealing pumps. The seal industry offers many ways of sealing and pumping systems are generally the driving force in choosing a seal for your application.
T.E.M.P. is an acronym that I was taught years ago. (T) Temperature, (E) Environment, (M) Media, and (P) Pressure. This can be expanded, but this acronym can be used as a benchmark. You will have to drill down to get additional information. Sealing surfaces (or shaft) material makeup, finish, and housing bores are also key considerations. Generally speaking the overall process will have to be evaluated and not just the seal. Many service calls I have attended involved the statement, “the seal is leaking”. The seal leakage generally points to a system issue and not a seal failure. This is not to say a seal doesn’t sometimes fail but just a reminder to remember to capture all the information.
This is the beginning of an ongoing series that will be addressing seals and sealing information. This first article will be the big picture view, if you will, of seals. Seals come in various materials, designs, types, and costs. Seal classes are generally described as lip, PTFE, bearing isolators, hybrid, or mechanical seals. Within these classes are various sub classes and generally in rotating applications. This is not to say there are not exceptions. We will drill down into more detail in future articles. My goal is not to evaluate the pump as that is covered well by others within this website. My focus is the seal and how to better understand it and its fit within the system. Some consider seals as a commodity part, but to others it is a critical component to their system. If a seal fails and causes a loss of thousands of dollars to the system due to repairs or warranties, it highlights the importance of the seal and its true cost.
If you would like to learn more about sealing, visit www.gaskets-seals.com