what is a snag???

[wisandsouthernkid]

i had been talking to an old railroad guy and he said that he had to check friction bearings to make sure that it was not snagged what does that mean? does that mean that it is ceased up or spun or what. Please help me out im confused!

[KCSfan]

Sorry but I've never heard of the term "snagged". Journal bearings were routinely checked by car knockers who would lift the journal box lid to see if there was sufficient oil impregnated cotton waste in contact with the journal to provide adequate lubrication.

Mark

[soilredneck]

The old style plain bearings relied upon a completely smooth surface on both the journal end as well as the brass.  Any imperfection in the journal end would "snag" the oil soaked cotton packing in the bottom of the journal box, carry the cotton to the top against the brass and prevent the oil from lubricating the brass and journal contact points, causing a "hot box" and  maybe even causing the bearing  end of the wheel to fail and break.  As you can see, this was a very important inspection.