Old 19th May 2017, 10:37
  #1802 (permalink)  
Join Date: Jun 2016
Location: Aberdeen
Posts: 87

Indeed, the crack has to be initiated somehow and it appears from the report that it was from one of a series of micro-pits 15mm - 16mm from the top face of the bearing, so all of them slightly below the line of maximum Hertzian pressure at 14mm but where sliding contact might begin. That it was not one isolated micro-pit (a rare occurrence in itself) but one of several in a row is, I think, a clue as to how it came to exist. Those other micro-pits should give the metallurgists something to analyse.
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