Steam & Excursion > Bearing Surfaces Between Front Engine & Articulated Boilers ??

I'm curious and seeking photos, videos, and explanations of the type of design and construction used for the bearing surfaces between the underside of loco boilers and the top surface of the front engine on large articulated steam locomotives.  I assume such surfaces were a heavy plate steel on top the cast frame of the front engine and a similar lubricated mating steel plate mounted beneath the boiler.  Or could it be a roller type bearing attached to the underside of the boiler?  

I'm thinking in the recent restoration of the UP4014 "Big Boy" there might be photos that would show these features on the front engine and the boiler to support the massive weight of a boiler's front portion.  

Possibly someone can post here various photos used by various loco builders or various railroads (coal hauling eastern lines with heavy grades or western lines) using articulated locos in the steam era or at least reference material for such.  Any help is most appreciated.

If this doesn't answer your questions, just let us know.  We like to teach!

https://www.trainorders.com/discussion/read.php?10,4477120,4484293#msg-4484293

-John Stein, aka Larry Doyle



Edited 1 time(s). Last edit at 09/01/19 19:40 by LarryDoyle.

I think the front boiler support is resting on the I-beam on the shop truck in this photo of C&O 1309:
http://www.rrpicturearchives.net/showPicture.aspx?id=4999673

I think the corresponding support on the front engine frame is visible on the frame just ahead of the valve gear hanger, painted in red lead in this photo:
http://www.rrpicturearchives.net/showPicture.aspx?id=4999675

Corrections welcome if my assumptions are wrong.



Edited 2 time(s). Last edit at 09/01/19 19:59 by CPR_4000.

LarryDoyle Wrote:
-------------------------------------------------------
> If this doesn't answer your questions, just let us
> know.  We like to teach!
>
> https://www.trainorders.com/discussion/read.php?10
> ,4477120,4484293#msg-4484293
>
> -John Stein, aka Larry Doyle

This explains and shows the bearing area very well with the photos and text Larry.  I was hoping someone would have some close-up photos of the UP4014 bearing while disassembled and under restoration.  Much thanks to you and others for offering the photos and explanatory postings here.

The piping had to flex as well.   what materials and methods were used to accomplish this?
thanks
D.

Sometime more than 20 years ago Trains magazine ran a lengthy article on the UP's 4-8-8-4s. Much info was given on the articulation aspect. Most fascinating was the drawing (or was it a photo?) of the slightly angled V shaped plate that showed how the weight of the front of the locomotive was transferred to the leading truck. As the track's degree of curvature increased, more locomotive weight was transferred onto the front wheels for an even better grip of the rails.