A small fatigue crack was associated with this casting flaw. A small area adjacent to the inner radius of this knuckle had a porous granular appearance consistent with a casting flaw ( Figure 12). The fracture surfaces of the box car knuckle were cleaned for examination. The concentrations of carbon, sulphur and phosphorus were not determined. Standardless energy dispersive x-ray spectroscopy (EDS) analysis of the locomotive knuckle material gave manganese, chromium and silicon contents consistent with the AAR specification. The 2 knuckles were sent to the Transportation Safety Board of Canada (TSB) Engineering Laboratory to determine the possible cause of the failures.ĭirect Rockwell A hardness testing of the locomotive knuckle material gave an average value of 59.6 HRA, which is equivalent to 222 HBW and within the AAR specification range Footnote 1 of 211 to 311 HBW for this class of knuckle. The knuckle on the forward end of the box car (CIBX 172032) had also failed ( Figure 2). 1.2ĭuring the field investigation it was noted that the knuckle and pin from the aft end of the number 2 locomotive (MMA 5026) had failed ( Figure 1). The 5 locomotives and VB car did not derail and travelled approximately 4435 feet past the point of derailment before coming to rest. Numerous tank cars ruptured, and a fire ensued. Sixty-three (63) of the tank cars and the 1 box car derailed. The train consisted of 5 head-end locomotives, 1 VB car (special purpose caboose), 1 box car, and 72 Class 111 tank cars. On 06 July 2013, a unit train carrying petroleum crude oil operated by Montreal, Maine & Atlantic Railway (MMA) derailed in Lac-Mégantic, Quebec. View document in PDF 1.0 Introduction 1.1
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |