Vacuum Pump Root Cause Analysis

JBW was engaged to conduct a root cause analysis on three large, 2,000 HP vacuum pumps at a Tennessee paper mill, where persistent reliability issues were causing excessive downtime, primarily due to reduced bearing life.

Leveraging our deep expertise in rotating equipment, we determined that the most probable cause was a combination of initial misalignment and inadequate shaft thermal expansion allowance. This led to radial bearings absorbing unintended thrust loads, significantly shortening their lifespan. Our analysis proved accurate when a spacer was identified in the shaft coupling, restricting thermal growth at operating temperatures. To resolve the issue, JBW provided detailed drawings with calculations for optimal initial shaft height, a refined alignment procedure, and on-site support during the shutdown to oversee shaft coupling replacement and pump realignment. Our comprehensive solution restored operational reliability and minimized future downtime.