830MBs scrapers still in use

Wonder if the ring and pinions were reversed so the pull was on the correct crown of the gears?

there is an 830mb for sale not far from me.

Was that 830 / scraper a sales model or something someone put together?

Hi Neil,

here some good background informaton on the 830Ms found here in the bulletin board: http://www.acmoc.org/bb/showthread.php?7684-US-Army-Scraper On thing I noticed: The 988 has a simple articulated joint and a pivoting rear axle, the 830M seems to have a "universal" joint like an ADT and a fixed rear axle.


[quote="OzDozer"]The 830M and 830MB were built from 1962 to the early 1970's. I don't have a precise end date. Military equipment built by Cat either has a very similar civilian production equivalent, or no civilian equivalent at all. The 830M and 830MB have no civilian equivalent, they were built to supply a specific Military Contract.

The early 830M production has a tractor S/N of 41E1 to 41E499. These were cable operated machines. The next version, the 830MB was hydraulic, and S/No's ran in three groups, according to Military Contract purchases. The second Contract purchase was for 300 machines, 41E500 to 41E799. The third Contract purchase was for 200 machines, 41E800-41E999. The third group was for an unknown number of tractors, 41E1000-up .. this was possibly another 200 machines. I do not have the total number built in this third Contract purchase.

The bulldozer blades are exclusive to the 830M and 830MB tractors, they do not have any civilian equivalent, and they are in two groups .. cable blades from S/N 45E1-45E499, and hydraulic blades from S/N 45E500-up.

The tractor unit was based on the 988A model of front end loader, and it used basically the same components as the 988A, except the tractor unit was reversed, as compared to the 988A, and the rear part of the tractor was a different structure to the 988 tractor, as it did not need loader frame mountings, just a hitch for the scraper. The engine of the 830M and 830MB is identical to the 988A - the D343 OHC engine.[/quote]


Best regards,
Max

Hi, FatCatGotHot.
Can you imagine just how UN-stable a wheeled front end loader would be with a loaded bucket fully raised if the back axle was fixed and front axle pivotted? For a LONNNNGGGG time, Cat track loaders had a RIGID track frame - NO oscillation, It was only when they went rear-engined and hydrostatic drive that they built in LIMITED track oscillation.

The two machines, 988 and 830M, are made for vastly different applications and thus have very different design characteristics.

Just my 0.02.

Deas,

you KNOW I am a creative guy and can imagine a LOT. LOL

I am not surprised about the fixed front axle on wheelloaders. Deas?! Please. I am rather curious, why CAT gave the 830M the universal instead of keeping the pivoting axle under the engine. I think some ag 4 AWD tractors are designed like this. Probably too much stress in this area pulling a fully loaded scraper, I dont know. EDIT: When you pushload one 830M with another one, the universal joint works better than just the pivoting axle under the engine. I think that's it.

Cheers,

Max

Hi, FatCatGotHot.
I dunno. I have never 'ackshully' laid eyes onna 830M in any shape or form. That said, and hazarding a couple of guesses, I suspect that if I was designing something like the 830M to both pull a scraper and carry a dozer blade, I would be looking to have both steering articulation and lateral oscillation in the middle of the tractor.

I would want to keep the back end as solid and robust as possible to carry the weight of the front end of the scraper and I would want the front axle to be one with the frame carrying the dozer blade to give better control over the blade and to keep it stronger to withstand the stresses of dozing and pushloading.

Does that help?

But what would I know? I'm just a 'pore, dumb bulldozer operator'.

Just my 0.02.

Hi Deas,

that's it. You nailed it. It is the solid axle on the rear and the dozer blade at the front -and you need some stress relief at the articulating joint. Yes, this was helpful. You know what? There was another CAT design, the 988 Carry Loader with a second bucket at the rear, where such a universal joint might have been helpful, too. CAT had to rebuy these machines quickly after they brought them into the market - because of stress failures in the frame.

Thanks for sharing. I really mean it.

Cheers,

Max