CAT D11T Dozer push loading 657E scrapers and doing some reverse ripping. Grading for a large new house pad and lot. New D11T undercarriage ordered and on its way.
One project I was on, the safety man was concerned about the braking power of the 657's, and the boss told him those guys have the best brakes in the world. If they need to stop, all they have to do is drop the bucket, and it'll stop fast enough to pitch the operator through the windshield.
Lol - that's the truth! I bought an old Cat 212 grader a while back and the brakes didn't work. The guy selling it to me said "don't worry, you just drop the blade - best brakes in the world!". Technically true, but I still fixed the brakes.
It all seems mundane and innocent until you realize that’s a D11t pushing the scraper. The dozer weighs a quarter million pounds and has 850 horsepower. The scraper has another 950 horsepower. All that power means they can load the 40 yard bowl in about 40 seconds. It’s absolutely incredible. One seamless motion and the scraper never stops moving forward. Super efficient.
Exactly, time is also money and on a government road building or civil engineering contract it’s about moving the max amount of dirt in the minimum amount of time this too is efficiency , taxpayers are footing the diesel /labor costs so price is irrelevant at this stage, again efficiency in action the dozer is productive in both directions of travel , ripping and pushing
Wow, I was a Heavy Equipment Operator for 8 years and had never been around a D-11 in the particular job I was in, but I never realized how freakin big those thing’s are until now seeing it behind that 657! Dwarf’s it!! lol…
The biggest one I’ve seen in person was a d10 and even those are gigantic so I can only imagine what an 11 looks like. A heavy haul company hauled a d10 complete to a truck show I went to on a show truck with a pristinely paint matched 48 tire trailer which was a sight to see in itself.
@@Podus81 when i was a kid, enamored with machinery of all sorts, a d9 was the rare unicorn I’d always be waiting to see. Scared my mom a few times yelling for her to slow down 😂
Fantastic A dozer spends half its life doing bugger all but reversing and using fuel to do it. Reverse ripping after a scraper push in rocky soils is a no brainer . See how that cat dozer does not flinch with the weight of the dozer blade counteractng anything the ripper comes up against? Wish i had invented that idea!!
Reverse is usually higher speed and adds a lot of undercarriage wear, so ripping at slower speed in reverse probably adds to undercarriage life. Win win.
@@ArthurDentZaphodBeebI think the concept of reverse ripping is interesting and I can see multiple benefits to doing it such as time saving, fuel saving, reduced wear and tear from making two 180’s if ripping going forward, as well as potentially reducing the occurrence of accident(s) from not spinning the dozer twice to rip going forwards and spin the dozer again so it can push the 657. However I do wonder about undercarriage wear especially on the track chains and possibly the drive. Look at how the tracks move on the machine when pushing forward and then watch the tracks where backing up when the machine is not ripping and then again when backing up and ripping. When backing up and not ripping the motion and slack in the track between the high drive sprocket and the rear roller the motion and slack in the track going forward when pushing and when backing up when not ripping. However when backing up when ripping the track between the high drive sprocket and the rear roller becomes as tight as the preverbal banjo string. I would think this would have to cause some sort of problem with the drive units over time and possibly accelerate track chain wear/stretch among other things. I have no poof that my hypothesis is correct or incorrect just a gut feeling based on what I am seeing. Have a good day and a better tomorrow.
@@ArthurDentZaphodBeeb Yes agree, I think those cat designers will be looking at this if they are not already. Anything that increases the productivity of a dozer up from its nominal 50% is on a winner provided it does not wear itself out in half the time.
@@dennisholst4322 Yes your right . But how about a dozer kitted out to rip forwards and in reverse then its 100% untilised. Obviosly it cant doze both ways as nothing calls for that so that utilisations stuck at 50%. Take you point here tho.
Makes me think like car tires, where does it all go? That has to be hundreds of pounds of steel missing from the original grousers. Maybe its over 10,000 hours or whatever.
@@TronVila yep, there should be hundreds of pounds of steel dust where this works. I figure rubber tire debris is lighter and blows away or it floats in a rain.
Never seen a scraper push loaded. Pretty cool party trick! Is there a benefit to reverse ripping as opposed to forward ripping? I have no heavy equipment experience. I'm just a stupid machinist lol
That’s amazing. When you think about it that Is all the power available from Caterpillar at that time. Twin engines on the scraper and a D 11 dozed and it still stalls or spins out.
If the machine was under warranty and there is an issue, Caterpillar will not pay, I saw it happen. Besides, that undercarriage is worn out, and those job condition are not that rough in the video.
Seems like a great product opportunity for Cat: create a tractor optimized for both forward and reverse ripping. Anyway, excellent efficiency SCEM, as long as not creating undue wear, or damage.
What about when on bulk push down a 20% grade and reversing a 110T back up it.....lotta load on cannons & recoils then.....ripping 1 to 2 feet deep in reasonable material like they are working is not an issue
That's chasing the dollar both ways ! You guys are awesome !who ever put this company together in my opinion should give some advice to the government because some of your jobs are as big as a city and the amount of overhead bigger than some town's budgets keep it up !!
Ya that’s what I was going to say. I would probably say it needs a complete new under carriage . It has been a long time since I have saw anyone let a piece of equipment get that bad .
Am I right in thinking that the ripper is in backwards, as if you want the ripper it is more money an hour? This is how it used to work in the English China Clay works (ECC), if a dozer was hired just to push tips and scrapers it was easier for the dozer that ripping and pushing. I used to drive a D10R 85 tonne, but would love to have a go on this weapon though.
Very unusual indeed ! I guess they must have consulted CAT technicians before proceeding with this "bizarre" ripper assembly, because I think it surely must generate unusual stresses on the cylinders and other parts ...
@@williammain3247 I think the reason is purely economic : "Time is money!" as you know, by proceeding in this way each movement of the Dozer is optimized, in forward gear it pushes the Scraper and in reverse gear it rips up the ground for the next pass, so no unnecessary U-turns. This undoubtedly corresponds to a high cadence with close Scrapers rotation, so no dead time for the guy in the Dozer ! Usually, we see 1 Dozer for the pushing and another one for the ripping, so here again, economy of means thus economy of money ! But here in France we don't use this method.
The bigger worry about reverse ripping is that it reverses the stress (push/pull) compared to forward ripping. if they do both with the machine that's a great way to greatly accelerate metal fatigue. Same reason why excavator sticks break in no time if they're sometimes used with the bucket the other way ("pointing away from the machine").
That big girl is gonna need new shoes to dance with soon , reverseing puts loose track on the ground and thats when they wear ... bushes n pins , but if you're chasing a profit.....
@@Gavin84w Dead right there. In theory a dozer is only productive in half its life, going backwards is unproductive. Just like a scraper is only making money when it is going to the fill with a load on.
How many scrapers are running to keep up with one dozer? Does it not cause damage to the rear of the scraper? So cool to watch I feel more masculine now 😂
They can get away with this because they are only ripping topsoil they are able to move with a bucket scraper, you’d never try that ripping rock at a quarry. Someone was using their head on the fact that dozer has to backup after every pass so let help the scraper out by ripping on the retreating pass👍
2 things here a company in San Diego did this many years ago on a new machine and the Cat dealer told them the warranty on the ripper would be void, also what God's name ripping 1 foot deep makes any difference, nice videos
why would you want to rip much deeper in a scraper cut? scraper only cuts 1-2 foot deep to load and with the scraper rolling over anything deeper it just packs it back down
CAT makes a front blade with rippers on the back of it so that it can push forward and rip going back. When it goes forward the rippers are hinged so they fold up and drop down when forward motion ceases then rip going backwards. Not uncommon on D7s and D8s in certain applications.
Yep , some of these guys need to go back in look at the old days, nothing new in what's happening there. They did it all with cable blades and pony motor starters on 7 8s & 9s
What about pin, bushing and sprocket wear? Most wear happens in reverse, under load the wear would increase. A very good description of track wear. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-tRdsSyt55L8.html One method to reduce wear in this operation , would to run rotating bushings.
Can't figure out why it doesn't have retractable ripper behind blade. It could rip either way and still push. Makes to sense to move a 200000lb machine and it not doing useful work. Productivity is money. No money in moving about just getting there.
I been doing this most of my life and that D11 ripping in reverse has got to be on the top 10 list of stupid things you can do to destroy a machine and another thing that is really dumb that is using a D11 with a s blade to push a scrapper I see no reason to even have a D11 on that job D11's are for rock not pushing scrappers and ripping potatoes dirt the cost per hrs to run that D11 far exceeds the money they are making per hr on the yards of dirt they are moving and that's how you get paid a bid is around 1 to 3 dollars a yard and what I see has got to be 10 or 15 dollars per yard maby higher and yes dirt you can rip with a D8 or D9 is potato dirt and that's what I see..
Ideally it is a 651 job, short haul, minimal grades and a short loading area so no need for twin powers as they just cost more to run, but they may only have 57,s available, the material is rocky so they are treating the job like they would use 51,s by pushloading them, D11 does not have a lot of time between scrapers so reverse ripping a shallow depth to help load the scrapers.