We often act as representatives going to rebuild shops to ensure our customer receives a quality build they deserve and to ensure the shops have the capabilities they sell. As well, we also oversee equipment installations and commissioning. One particular plant site went thru 8 blowers in 15 months and nobody could figure out why this was happening. When API went to site they pulled the equipment and did a failure analysis in the field finding the previous rebuild shop was using worn out parts and band aid fixes to get the equipment out the door. API worked with our client and a local rebuild shop to come up with a lasting fix as we didn’t have the time to wait on new parts. We found that the shaft splines and the timing hub splines had been fretting due to the severity of the service loading up for 1 minute every 30 seconds. This caused a ratcheting effect on the shaft and hub splines causing the blowers to lose time and rub rotors further causing bearing failure or worse a split casing.