I have a D8T working on a shale quarry. When working along a slide or pile the shale falls into the chain and over tensions the chain when going around the idlers. Our older dozers with conventional style tracks don’t have this problem. This will destroy the undercarriage and needs to be remedied. Cat doesn’t offer a rock guard system. Cat has been unable to provide a solution to the problem so far. Has anybody run across this problem?
Can you post a Serial Number. I'd be interested to see if the tractor is equipped with idler guards. Also does it have SystemOne or conventional Heavy Duty undercarriage installed.?
Probably not applicable here but older crawlers operating in certain conditions such as snow had holes cut in the pads to relieve compacted material.
Are you running a full u-blade? Sounds to me like the operator needs a bit more training.
Nige, yes it is equipped with guards on top of the idlers, but not on the bottom. The material is filling the chain on the ground side as it passes through the pile, then as tries to pass around the bottom of idlers(forward or reverse) it tensions out the track because the material has nowhere to go. My thought was to cut holes in the pads
no Shimmy1 that’s not the problem thanks
DB 1 I think you’re on the right track. That is what what I was thinking, but I don’t want to spend 15-20m on pads and find out that didn’t solve the problem.
Well, in my world, which is over 35 years of operating equipment, when **** is getting where it doesn't belong, the solution is to change the operating parameters, not add more **** to keep the other stuff out. Unless Nige tells me to watch my own bobber, I'll stand by my statement. The only two materials I've seen holes blasted in the pads to accommodate are snow and mud. You are either trying to push material out of a stockpile the wrong way, or trying to push along a slide, which never works. I don't have the answer for you, I just know that it might be a fool's errand trying to throw parts or modifications at this problem.
Can you post a couple of photos of the machine at work.? Especially I would like to see where/how the material is piling up that gets into the lower run of the track links and buggers up the tension. Also what width of track shoes is it currently running.? I can see what it was built with but that was obviously a while ago.
Cat offers center punched shoes that help with plugging. We used them on our 8R. You can cut the holes in existing shoes also.
Holes are also punched in pads on "Landfill Arrangement" tractors
Yes I did exactly as you said to a brand new Komatsu D65 back in 1995 with a torch on the center of every pad. They were packing tight with snow turned ice and making tracks way too tight. I cut every single pad on both sides and that was the end of the problem. Would it work in your situation, can't gurantee. Mine was a dozer working in deep snow all the time. Simon C
You could take the opportunity to upgrade to a D155 Komatsu with standard tracks fitted with standard track guards and the problem would be solved . Apart from getting on top of the shale I see no other way to move it than cutting along side it . On the other hand I bought the last quarry dozer of a reasonable sized quarry chain who now don't have dozers with diggers being the order of the day .
It’s either a 22 or 24in shoe. I’m not currently at the site, but material slides down on the track and fills the gaps between the rollers. When it tries to go around the idlers the material has nowhere to go. I think cutting a hole for relief is probably the right answer
I don’t have a problem with Komatsu, but we don’t have any customer support for them around here
Cool story
What distance are you pushing? If the blade fills up and over flows or causes excess material to fall it's adding to the problem. Taking a lesser cut or moving away from the pile a bit may help. Maybe there is a way to make kind of a roadway then push material onto the road way instead of just cutting into the side of the pile and pushing the full distance. Kind of similar to corner loading a bucket. If the material is falling down sometimes you have to move over so you're not driving on it. Not sure how holes in the pads would work with shale.
Don't bother. My observation is his operators are too belligerent to try different techniques to solve this problem. I've pushed up a whole bunch of gravel over the years, both from a pile and next to a cut. It sucks big time trying to keep the material out of the rails. No amount of fricking holes in the pads is going to let 2-6" rock fall out, you HAVE to change how you approach the material. Last point that I'm going to make. Trying to mitigate this issue of material getting in the rails is definitely having another effect, and that is rapidly increased rail/idler/bottom roller wear. I'm guessing they're probably getting closer to half the number of hours out of these rails as they should be.
Even though I have cut the holes in pads I think Shimmy is correct, it won't do nothing in shale falling in between the rails. Simon C
Saying that the design of the tractor is the problem, when this has been an issue since the first dozer was created, defines the issue in my mind. As mentioned, holes in the shoes help with certain materials that tend to pack in the sprocket teeth. The problem here is flooding the track frame with material, not packing. Using a narrower dozer like a straight or semi U versus a full U exacerbates the problem, but either way technique is the solution like Shimmy1 stated. Maybe, production per hour is slightly higher by side cutting a pile of loose material, but cost per unit will certainly be higher given increased undercarriage wear and downtime. Just my opinion, but it sounds like the OP should go back to 8Ks, or run another brand.
You really shouldn’t use words you don’t understand bro. You don’t know my situation, so try to understand before you throw around the insults and tout your operating experience. It makes you an a***ole. By the way, they do make shoes to help alleviate this problem. Go educate yourself before you start running your mouth.
You may just have to allow for more frequent undercarriage replacement. Have you tried running the tracks looser to see what happens?
While I don’t have a dog in this fight I would say it’s in poor taste for a new member to talk **** to one who’s been here a long time and is trying to help. While you may not care for his delivery I suspect his observations are on point.
My apologies if you feel my approach was too forward, but my opinion stands. Ninety-five percent of my operating hours (somewhere north of 10,000) in a dozer have been pushing loose or bank-run coarse gravel, containing anything from 2" to 18" rock, pushing 8' deep waterline trench closed, pushing spoil piles back into a hole after pushing rock piles into the hole, and pushing out fill piles that were dumped with an end dump or side dump. Every single one of these operations require strict observance of certain protocols in how you approach the pile, or how long you run along the cut. Anything that gets attached to the track frame to prevent entry of material is going to be placed in close proximity to a moving part, whether that be a track pad, chain, idler, roller, or sprocket, and that is where things go sideways. There is going to be a specific amount of clearance required, and there will be considerabe amounts of material smaller than this clearance that will be trying to wedge it's way into the gap. You may be able to keep the sluff out of the bottom rollers and idlers, but you're going to create a different problem, and that is your operators are going to try and push their way through even more sluff, potentially overloading the shields that have been installed. I'm guessing you hoped someone on here would give you the magic bullet to this problem straight-away, but from the responses that seems to not be the case. Once again, if I'd only have minor experience in pushing in extreme conditions, I wouldn't have came off so strongly. I've ripped off tension cylinder shields, roller guards, and sprocket guards. I've broken idler slides, broken sprocket segment bolts, and once had a rock get behind the sprocket on a smaller Case dozer and pull the sprocket shaft from the housing, destroying it. We wrecked an entire undercarriage in 1000 hours pushing snow one winter. Material flooding the track frame is definitely a problem with dozers, but adding more stuff to try and keep it out is not the answer in my opinion.
We are using the old D8H for those certain tasks because they don’t have this issue. The T works good up on top for ripping and pushing but can’t handle getting the fines getting in the rails. It’s never been a problem with the conventional track. I think cat needs to rethink some things with the high track
Are the same operators running the 8H that are running the Ts? And, you haven't said yet what blades you're running on the Ts. If they aren't full U, that will factor in, even though some don't believe it.
I can't see how the high track would make a difference all things being equal. Does the blade on the D8H stick out more from the tracks than the D8T? Would help to see the piles you're pushing and the blades on both dozers. If you're getting too much material in the tracks you need to do something differently.
All blades are SU. It’s not a push and carry situation and it’s all hard rock that has to be ripped. Most of th time it rips and shorts pushes to 988 that loads over the edge. All the same operators with 25-50 yrs experience with different situations. Nobody can keep the fines out of the rails. It’s not the rock that’s the problem. The fines just compact on the T trying to go around solid idlers. They have a chance to escape on when they hit a sprocket on a low track.
It sounds possible that punched pads might help in your case IF, and only if your guys are at least attempting to keep out of the sluff. The punched pads are only going to let so much material drop through.
Holes in the pads may be the best option to try.
It’s a proven solution in other materials.
I thought he was talking about shale in general which can be larger size like rocks.
From the first post, I imagined a standard dozer with a ripper, and already guessing there was a bunch of ripping going on. So, when they start pushing, they're going to have material constantly falling against the push beams, and getting picked up and dropped around the rear idler. Shale is kind of a bugger sometimes, since it's been ripped it's all fractured to pieces and doesn't take much to turn into powder. A full U-blade would definitely be better, once you get the blade loaded you can swerve out of the loose stuff, but it would definitely be more difficult to get started after ripping is done. I think punching holes in the pads will help a little, but the operators will have to change their approach to fully solve this. I'd like to see some pics of the operation, as well as close up pics of the track pads. I'm going to venture a guess that the back edge of the pads is sharp like a razor, and there is a bunch of material falling down through the gaps as the rails move around.
Thanks for your input. I don’t have any specific pictures right now. I’m out of town until next month. I’m going to lean on cat to stand by their product and see what they have for a solution before I spend money o. It. The problem can be worked around for the moment and works good for ripping and slot pushing. Keep you posted Thanks
I think if the material just slides down and gets in the tracks slot pushing/dozing would add to the problem.
Based on my experience a dealer branch, or even their head office, is unlikely to have in-house expertise to help you in these specific circumstances. They will need to call on the Applications Specialists from the Track-Type Tractor Division in back at Cat HQ in Peoria. It may pay you to mention that the first time you contact the dealer. I would also strongly suggest that you get some video of the machine operating clearly indicating the issue that you have so that the dealer can forward it on to TTT when asking for their suggestions. Also you have to bear in mind that this particular D8T is by now an almost 20 year-old tractor (built 2007) and to a large extent the level of assistance you get from the dealer could be very dependent on how much you spend with them. Sorry to say that but it's the way of the workd.
You’re absolutely correct. We’ve been doing business with them since the 80s. I’ve been told they are working on getting an application specialist involved. We’ll see what happens. Thanks
In my dealings with them I've found the Application Specialists to be pretty sharp cookies. As per everything, what you get out of it depends completely in the level of information you put in. The more information they get the better-tuned will be the answers in relation to your specific operation.
From The Nige As per everything, what you get out of it depends completely in the level of information you put in. The more information they get the better-tuned will be the answers in relation to your specific operation. I challenge anyone to say it better!
I came across something else. Information supplied by the OP is that the tractor is equipped with an SU blade. According to the build data for S/N KPZ02321, which I know was a while ago, it was originally shipped equipped with a full U-Blade. Would you like to check the upper RH corner of the back side of the blade for a data plate and pull the S/No from it.? I see DZB00303, Part Number is either 246-8150 or 246-8151.
Having owned a pile of D8H/K/R and D8T dozers,I have experienced this problem myself on occasion pushing out stockpiles. I tended to drive the D9T myself as she is around the 34,000hr mark,so I’m very conscious of the damage and costs encountered with material filling in the rails when first pioneering a stockpile to get on top of it to push it away. As Shimmy says,adjust your operating style until you get on top of it. I can’t see how a conventional track 155 or D8K is going to help things.
It looks like the dozer is doing two different jobs . Only way to stay away from the wall is with a wider blade . Having an angle blade would do whats needed in that . Finding one bit of a mission . Big digger with a sonic ripper along with assorted buckets is what the quarry who sold me one of my dozer uses , track wear is not an issue for them now . There are some very serious pictures of big high tracked dozers with folded up track frames that may have got abit too tight .
Can you post the pics.?
Hence my earlier question regarding the blade it's actually wearing now if it originally left the factory with a full U Blade, not an SU.
As well as my very first question in post #4.