Bearings failure mode analysis

Analysis parameters should be established to monitor the key indices of the compressor s dynamics and failure modes. These indices should include bearings, gear mesh, rotor passing frequencies, and mnning speed. However, because of its sensitivity to process instability and the normal tendency to thmst, the most critical monitoring parameter is axial movement of the male and female rotors. 

In order to verify that the RFS technique can detect, particles greater than 10 pra, the U.S. Department of Defense Joint Oil Analysis Program Technical Support Center (JOAP-TSC) prepared samples using M50 alloy particles. M50 alloy is often present in aero-derivative turbines. Some failure modes of J52 engines appear to be sudden catastrophic failures where the root cause began with the lack of lubrication of the 4 A bearing area. Initially, analysis of the samples by RDE spectroscopy did not indicate the failure mode [6]. The composition and specifications for MSO alloy are as shown below (Table 3). 

A subsequent review of stress analysis and strength prediction of fibre reinforced plastic (FRP) mechanically fastened joints [41] identified five common failure modes tension, shear, bearing, cleavage and pull-through (See Fig. 2.11). The tensile strength of a single hole joint is said to depend... 

The failure analysis is carried out according to section 5.2.2.4 of the EUROCOMP Design Code. The net-section, bearing and shear-out failure modes were evaluated. For... 

The embankment was to be constructed of quarried chalk, with a basal layer of reinforcement. Computer analysis concentrated on the embankment and its reinforcement. Midway through construction, the embankment slipped sideways, remaining relatively intact, somewhat in the manner shown by the finite element analysis in Figure 4, which indicates a combined sliding and bearing failure. Analysis of this mode had not been considered, perhaps because it is quite complex and the significance of the extremely low strength of the muds was not understood, but mainly because of reliance on software that did not include this type of failure. 

This report evaluates recent performance of DGs and all DG vendors with the exception of Transamerica Delaval, Inc. (TDl), because of the emphasis already being given to TDI diesels in other studies. For the period 1980 through 1983 inclusive, BNL reviewed and evaluated DG failure data, DG vendor inspection reports, the TDI lessons learned as they related to the other vendors, and previous pertinent studies. The data sources used for DG failure analysis were LERs, 10 CFR 50.55E, Part 21, NPRDS, and EPRI document files. The DG failures were classified relative to the DG component that failed (e.g., main bearings, starting system). The failures were also categorized and analyzed by mode, manufacturer, and cause. Manufacturers with significant failures are identified in the report. 

---