Royal Scot middle big ends.

E S Cox wrote that the GWR style bigend used on the Scots would not overheat even if a blowlamp was applied .

 

I would think that roller bearings on all axles would help in terms of locomotive performance in general.

 

In practice they made little difference to rolling resistance, it was reduced maintenance which was the incentive, on the LMS at least, along with manganese steel horn guides and matching axlebox faces. These allowed far greater mileages between works overhauls, which were then dictated by tyre wear on the mechanical side or boiler issues.

 

It really is little short of unbelievable that journal bearings work as well as they do. It is an art between ones that work well and ones that just don't work, but that Roller bearings are still, even today, not as prolific as they should be by right of being a far superior design (on paper) is scarcely believable.

A locomotive big end will function as well as: A. How well or not it is designed (Size/Shape Etc) and B. How well it is aligned.

If there is one guaranteed way to kill a bearing of any description, it's poor alignment. And miscalculated loadings obviously.

 

I heard that roller bearings are not used in large turbine generators in power stations, because the rollers would be destroyed by metal fatigue. I take it that this is unlikely to be a problem with locomotives?