Patented Rotor Spider Rim Ledge Repair by EME
The rotor spider is one of the most critical structural components of a generator, especially in large-diameter designs. It endures a complex combination of mechanical, thermal, and electromagnetic forces—including deadweight, centrifugal loading, vibration, and torque—resulting in high-cycle alternating stresses. A common failure mode is rim ledge fatigue, caused by relative motion between the rim and spider, leading to crack formation in the rim support surface.
Traditional solutions—such as complete spider replacement (often requiring over a year of downtime) or difficult and short-lived weld repairs—are costly and time-consuming. To address this, EME developed its Patented Rim Support Ledge Repair, featuring the EME Top Plate Design (U.S. Patent No. 12,316,177). This innovative solution extends component life, reduces downtime, and eliminates the need for full spider replacement.
The EME Top Plate Design provides you with the following:
- Permanent Repair (at approximately 1/3 cost of new)
- 40+ year life
- Does not require re-shrink of the rim
- Rotor can remain in place
- Short outage
- Easy access for inspection
- Replaceable wear components
