Selection Strategy For Mechanical Shaft Seals In Petrochemical Plants

Abstract

Petrochemical plants are confronted with an increasing number of available mechanical seal designs. The user must choose from among inexpensive standard seals and exotic, high engineered seal models. We have seen seal costs range from less than $200 to over $6000 for pumps which didn’t seem all that different to the superficial observer. Each of these has its place, although it may prove difficult to determine which seal should be used for maximum long-term effectiveness in a given application or service. A selection strategy outline, which makes maximum use of the capabilities of knowledgeable seal manufacturers is presented. The strategy avoids unnecessary proliferation of different designs or leads to the selection of high quality seals for the larges possible number of pumps in a given installation. While primarily developed for grassroots plants, this approach can also be used to systematically upgrade mechanical seals in existing installations.