On the EMD 4-wheel Blomberg truck, in some instances, I have seen two different types of bearing/journal boxes. They are considerably different; one having a round bolted-on cover on a vertical plane, and the other having a bolted-on cover that is rectangular and set an angle facing outwards and upwards. Often each of the two types is on one side of the truck. In many cases of Blomberg B-trucks, I see just the type with the round covers on all four axle-ends. What is the difference between these two types of boxes?
From what you’ve described, I believe you’re looking at the difference between friction bearing (rectangular) and roller bearing (round) trucks.
I can see where you might think that, but to my knowledge no Blomberg truck was ever built with plain (or “friction”) bearings, but all with roller bearings. The two boxes are just older style and newer style, as I recall.
There were a tiny fraction of EMD road locomotives built with AAR Type B (“switcher”) type trucks but even those were all roller-bearing, I think.
Bogie Engineer will see this and clarify, I hope.
RWM
The BRC GP7s had non-roller bearing trucks, and tires sweated on the wheels, like steam engine drivers. I think these were the only ones so equipped.
The older Hyatt boxes had the squares, and tapers. The newer ones are round. The shop trucks under this one have old and newer Hyatt boxes.
Some roads have retrofitted Timken-style sealed bearings, where you can see the end of the axle rotating, like a freight car.
Is it just me or is there something fairly odd about W&S 2055?
For a start, what do they call it?
It looks like someone took all the bodywork from a Paducah rebuilt SD20 as converted from an SD 24 and put it on the frame of a GP38! That is an SD24 radiator - nothing else had anything that looked like that. It has four stacks, so it probably has a 16-645E blower engine.
So please, who rebuilt it, when and from what?
M636C
its merely a Paducah SD20 rebuild sitting on a pair of Blomberg B trucks while its own Flexicoil C trucks are removed to allow for some kind of work, be it wheel and/or traction motor replacement, nothing more nothing less… Its not some type of newly fabricated rebuild. If you were to visit heavy repair shops of other railroads and/or rebuilders you would most certainly run accross a few locomotives sitting on shop trucks of some kind while its own trucks are removed for work.
Bryan Jones
Brooks,KY
I know this one!
The old style “square” and new “round” journal box ends are both for Hyatt cylindrical roller bearings. The difference is that each houses a different lateral suspension mechanism. The old style holds a leaf spring and the new a rubber “donut”. Since the axle is free to move laterally in the journal box, they provide some lateral cushioning between the wheel/axle assembly and the truck frame.
When Timken tapered roller bearing is used, the axle can’t move laterally in the journal box, so the cushioning takes place between the journal box and the truck frame - there are small rubber pads on the “ears” of the journal box.
Oltmannd, So you are saying that both type of boxes used the same bearing, but the box with the rectangular cover set at angle contained a leaf spring loading against the outer end of the bearing? I can see that box shape being needed to accommodate the length of a small leaf spring.
The W&S locomotive has the bearing box with the round covers on all four axle ends showing in the photo. Over the timeframe of the Blomberg truck use, I would say that the vast majority of them were as in the photo with all axles equipped with the box with the round cover.
The old and new explanation makes
In the case of the second generation units I believe what you are seeing is the use of trade in Blomberg trucks. I found additional types of units as in Great Northern and Santa Fe GP20s, Great Northern GP9Ms, New York Central GP40s from the first order in 1965, and an ex KO&G GP28 that had the square journal box end. There are many, many more units and railroads that recyled these trucks under newer motive power. I looked a photos on the Fallen Flags site for confirmation of the use of this type of truck on units built from trade ins.
Ed
[quote user=“Bucyrus”]
Oltmannd, So you are saying that both type of boxes used the same bearing, but the box with the rectangular cover set at angle contained a leaf spring loading against the outer end of the bearing? I can see that box shape being needed to accommodate the length of a small leaf spring.
The W&S locomotive has the be
It is a SD20 on shop trucks. The normal trucks were getting worked on.
If you think that is odd, look at this:
