I have recently replaced a 230/530 on a 102 tonne dryer. Failure analysis showed that fatigue was caused by an improper fit in the housing. There was fretting corrosion on the outside of the outer race in the load zone. The damage was extensive spalling of the outer raceway. The bearing and housing are only 4 years old. The housing was cast by the OEM of the paper machine not by the bearing manufacturer in this case. What I would like to do now is somehow measure or monitor any movement in the load zone of this bearing. Is there a sensor of some kind that can be placed inside the bearing next to the outer race to detect this? I was thinking of some kind of stress strip sensor. Any ideas?
ensing-dot-ron-at-irvingtissue-dot-ca
Posts: 450 | Location: Great White North | Registered: 21 February 2005
I found the followign discussion of a "stress pin" which sounds like it might do what you want. Maybe you can contact the company listed for more info:
quote:
Essential Concepts of Bearing Technology by Tedric A. Harris and Michael N. Kotzalas: Instead of considering failure at the occurrence of the initial spall, the ability to detect incipient spalling becomes important. This knowledge would most likely indicate the additional time in which to take failure-prevention action. With the continued development of micro-sized pressure, temperature, and ultrasonic sensors, which can be embedded in close proximity to, or directly in, the bearing, it appears probable that effective means to sense incipien t fatigu e failure will even tually be availa ble. Figure 14.17 shows a stress pin, a miniature pressure sensor, embedded in the outer ring of a tapered roller bearing. This sensor doe s not impai r bearing function , an d may be used to determ ine whet her bearing loading con forms to design. If bearing loading is sub stantially in excess of de sign, this is an indica tion of failure occurrence or incipie nt failure.
FIGURE 14.17 Stress pins inserted into the cup of a tapered roller bearing: (a) locations to determine axial stress distribution; (b) circumferential locations to determine distribution of load among the rollers— showing wireless connection of analog/digital converter for transmission of signal. (Courtesy of Oceana Sensor Technologies, Virginia Beach, Virginia.)
