Hello everyone, for my first thread initiation I thought I'd ask the following: How are modern dozers constructed as far as the base of the machine is concerned? (I may be using the incorrect terms here, so please feel free to correct me if I am.) By the base of the machine, I mean the bottom portion that sits between the track frames and contains such things as the hydraulic pumps, pump drive and diesel engine. Is it basically a rectangular 'tub' with four sides & a bottom welded together out of something like 1" steel plate? Is there some kind of bracing or an actual frame inside of that? Do the track frames have their own frame (car body?) connecting them to each other that the 'tub' is mounted on, or is it all integrated? I've tried using Google to answer these questions and have come up empty handed. Tried looking for cutaway drawings of dozers too and had no luck. It would be great if any of you guys would have some cutaway drawings to share or even some photos of dozers being assembled that might illustrate what I'm asking about. Website links to any helpful information would be appreciated too. Thanks!
Modern Crawler/Dozer construction Hi, Wolverine69. By far the great majority of direct drive and power-shift crawler tractors these days have the crown wheel and pinion case and steering clutch cases in one unit with two main chassis rails projecting forward from that unit to carry the transmission, engine and other hardware. There is usually a rather solid cross beam connecting the two chassis rails somewhere around the mid-way point. This cross beam is the contact point for the center of the equaliser bar between the two track frames. The track frames are usually attached at pivot points outboard of the back sprocket axle or through their own separate pivot shaft just ahead of the rear sprockets. In the case of the Caterpillar high sprocket drives, the track frames have their own pivot somewhere under the sprocket There are only two manufacturers that I am aware of who used any sort of tub or hull for a frame for their machines. Both are long defunct. They were Ansaldo Fossati of Italy and ADN (Acier Du Nord - North Steel) of France. ADN is still around in one form or another but has been out of crawler tractor manufacturing for a long time. Crawler loaders tend to have a somewhat more complex frame design to carry the loader arms, bucket and ram mountings. Hope this helps.