(6a) Application of Fiber-Embedded, Polymeric-Based Materials As Pump Shaft Bushings in Abrasive Services

Application of bushings manufactured out of polymeric-based materials that offer self-lubricity, temperature and chemical resistance in critical, clean-service pumping systems (e.g. boiler feed water) is well documented and continues to be adopted by various organizations.

An area of opportunity has existed for dirty-service applications. Typically, bushings in said applications will be fabricated of softer materials as a sacrificial component (e.g. brass bushings, cutlass bearings, etc.) and often have more generous clearances to allow passing of entrained debris and/or reduce shaft wear, while also affecting pump efficiency/performance and at times, pump rotor stability.

Use of polymeric-based materials designed for clean-services is not well suited for applications with solids/debris entrained in the service, as these will be eroded/worn in a relatively short time.

Fiber-embedded polymeric materials offer a solution by providing abrasion/wear resistance, related to the material properties of the fibers used, while also providing self-lubricity, chemical and temperature resistance seen in traditional, clean-service materials. Additionally, by allowing clearances to be brought in closer to (or meeting) API recommendations, pumping systems often benefit from improved performance and rotor stability.

This paper will address application of two types of fiber-embedded polymeric materials as shaft bushings in two vertical lift pumps, in dirty/slurry-type services