Spherical roller bearings are roller bearings with self-aligning capability. The structural feature of these bearings allows the inner ring axis to remain aligned with the outer ring axis even when they are relatively tilted (typically within 3 degrees), enabling normal operation. These bearings not only can withstand high radial loads but also maintain good impact and vibration resistance at low speeds. Additionally, due to their high rigidity, China spherical roller bearings perform exceptionally well under radial loads.
China spherical roller bearings have excellent performance advantages. When there is shaft deformation, installation errors, or uneven forces during equipment operation, these bearings can automatically adjust within a certain angle range, ensuring even contact stress between the shaft and bearing, greatly extending the bearing's and related components' service life, and effectively reducing equipment maintenance frequency and costs. However, spherical roller bearings can also experience failures.
During use, spherical roller bearings endure significant axial loads, causing one side of the raceway to bear larger loads, leading to bearing bias loads. During the operation of the entire bearing set, self-aligning capabilities are lost, causing fatigue spalling of the bearing raceway and roller working surfaces, leading to bearing failure. Below is the specific spherical roller bearing failure analysis:
If subjected to significant axial loads during installation or use, one side of the raceway may bear larger loads, easily causing bearing seizure, hindered rotation, and a loss of self-aligning capabilities, resulting in bearing failure.
The outer and inner raceway on one side of the bearing shows spalling and severe rolling damage, with spalling and wear marks on the rolling surface of the rollers on one side, and severe rolling damage to the cage on that side, indicating that the bearing encountered significant axial loads during use, leading to bearing bias loads. One side of the raceway bears larger loads, while the other side bears smaller loads, losing self-aligning capabilities and ultimately causing bearing failure.
The axial fretting corrosion marks at equal intervals on the inner diameter surface of the bearing's inner ring indicate significant vibration during operation or an insufficiently tight fit with the spindle, causing the contact surface to make small reciprocating movements. The surface asperities oxidize and wear off, resulting in fretting corrosion.
Additionally, two areas on the outer ring of the bearing exhibit martensitic structures that do not meet standard requirements, indicating improper heat treatment processes on the outer ring, resulting in non-standard martensitic structures that reduce the bearing's service life.
Severe rolling damage at the spalled area indicates that the bearing continued to operate after spalling until the bearing temperature rose and the temperature detector alarmed.
