I come the hook side of heavy equipment and you dirt fellows might know a thing or two when it comes to tracks. What is most abrasive on tracks- Sand, Gravel, Wood, Salt Water, Concrete, etc....:beatsme If I missed any please free to mention. Thanks:usa
All are! Sand is probably one of the worse for dozer tracks, wears down the pins, bushings, idlers, and sprockets faster than Normal dirt. Big rocks can bend pads and break corners off of the tracks. Mud is another track killer if not shoveled out properly. Mud can get packed tight in the undercarriage and when it dries it turns hard as concrete and can lock up your rollers. This can lead to flat spots wearing of not caught in time.
I did not realize dried up mud was an enemy as well, good call.
My honest opinion is that snow is the most abrasive.
Nothing eats up tracks worse than sand, small enough to get in between anything and not come out. Our dozer that we use is mostly used in the quarry or sand pits and after 6400 hours is not in bad shape but the other day I replaced the cutting edges and end bits and noticed a crack in teh blade, so I made some plates like I've done before and welded them on. The one spot I burnt right through with a MiG welder. Trbo
I would tend to agree that sand is the worst. One thing to consider when it comes to sand is what the makeup of the sand is. The sand our tailings dozers run in will completely destroy an undercarriage in about 1500 hours. Brian
100% on the sand.
There are two things I've encountered that are extremely abrasive. One is coral sand, made from coral rock excavated in Florida and other south coast areas. The other is slag or slag sand, which comes from the iron and steel making processes. Back in the seventies, while working in Florida ,our shop (an AC dealer) did our own track work. We did a lot for all of Florida, south Georgia and Alabama. Also work for some contractors in the islands down range, the ones now known as the windward and leeward islands. There were only three track shops in south Florida then, all had a one-eyed guy running the track press. It was a dangerous business you know. The standard practice back then was to buy a big tract of land, clear it of valuable timber, burn the rest along with the snakes and gators, then dynamite a big area and use a massive dragline to excavate the coral rock out of the pit and pile it up to drain. Some of this was used to build roads and fill in swampy areas, which in south Florida was a lot of ground. The rest, after draining down some, was run thorough big jaw crushers to produce sized coral rock and gravel, and lots of coral sand. The pit, when completed, was turned into a lake, surrounded by a golf course or two or three, a country club, and lots of expensive houses, plus a few cheap ones. Some pits, if close enough, were also connected to the ocean so as to let boats and fish in and out. The rock and gravel was used in various ways including asphalt and cement as was the sand. Now most of this stuff was moved after crushing and screening by front end loaders dumping it into OTR trucks of all kinds. The problem with it was that it ate hardened steel for breakfast! Loader buckets lasted as little as 500 hours before the bottoms were worn off and the edges destroyed. Crusher jaws were run all day and built up all night by teams of welders and guys like myself trying to make some extra bucks after a days work for the dealership. Dragline buckets were as plentiful as hens teeth, all being rebuilt and lasting as little as a couple of days before being destroyed again. SJ Groves, a large contractor from Ohio, got a contract to construct a long section of I-95 down through Ft. Lauderdale to Miami. Much of it was elevated right of way, which means that they brought in millions of cubic yards of sand for the roadway and overpasses. Groves brought in a bunch of new Cat D8H dozers to doing pioneering work and to spread that sand, coral sand. Their VP of Equipment and a Project Equipment Manager showed up at our shop one day soon after and asked to meet with my boss to discuss U/C wear and how we might help them with pin and bushing turns and grouser rebuilding. I sat in the meeting, as I was running the shop scheduling, including the U/C bays. After some pleasant conversation we turned to the subject at hand, which involved severe U/C and GET wear. My boss asked what kind of hours they were getting on the tracks of the new D8's? "About 300," was the reply. We about fell out of our chairs on hearing that. Seems that the Cats were running plain sealed links. There was no concept of SALT tracks then. OK, "how about after a turn," we asked? "There's not enough rail height left to do a turn," was the answer to that. "So what are you doing then," we asked? Well, they were installing every used set of tracks they had in the United States of their own, and were buying more anywhere they could find some that had a little wear left in them. They tried taking the seals out of the links and figured that while it might let the sand in, it would also let the sand out quicker. We snorted pretty good at that and the Project EM looked a little embarrassed, it was his idea I found out later. They asked what kind of life we were getting on HD21 U/C components and the boss mentioned somewhere between 600 to a thousand hours on new, with another 5-600 after the turn. They were impressed at that, and the boss asked if they'd like to talk to a salesman about trading the Cats for some A/C's? After a nervous cough and laugh, they said, "no!" Jokingly, the VP asked if A/C hardware could be adapted to Cat's, and it was his turn to fall off his chair when the boss said, "sure, I've done it before in Africa and India." Well, they were all ears as he explained that, as was I, for he hadn't told me that he's been with A/C in those places. I knew he sold sewing machines in India for some time, but what I didn't know was that he had also been a service and area manager in A/C shops in both India and South Africa for years. So they wanted to know the details and could he work up some pricing. "Sure," was his reply. Turns out we eventually got a contract from Groves to supply A/C tracks and rollers and modified segments for about two dozen D8's working with the coral sand fill sections of the I-95 project. We put together a modified sprocket, a modified roller frame with A/C rollers, and one set of A/C tracks and installed it on one side of one D8. The other side was all new Cat. This ran till the Cat side was worn out and made clear that, at that point in time, in coral sand, A/C had a better product. We then set to work with modification of two D8's at a time in our shop till all 24 of them were done. We also did some work on the dozer faces and the final drive housings where they were wearing thin on the inside under the brake compartments. Then there was their loader bucket wear problem. We couldn't modify any A/C buckets to fit their Cat's, but we did hire a couple of welders to work nights rebuilding the ones they had. We also looked into why they were having such wear problems and I never did hear exactly how that turned out. We sent samples of the worn parts to the A/C factory labs in Milwaukee and Peoria and there was some suggestion that the heavy concentrations of salt in the coral sand might be part of the problem, something to do with rust and electrolysis. I don't know how long this went on as it got just too hot and humid for me and the wife to stay in Florida. I had just done parts of four years in Vietnam and frankly, I was quite tired of heat, humidity, and did I mention bugs? Yeah, I was tired of them too. Not to mention the crowds of people during the "season," and the smoke from the fires burning in the Everglades that wafted into town every night with the shift in the offshore winds. So we left and went to Wyoming, which was and still is quite the opposite of Florida in nearly every way.
Now, the other material that is very abrasive, probably the worst in fact, is the slag. This was in the late seventies and Cat was out with SALT tracks, which we were running on a couple of D9H's at Plant One in Detroit. We weren't having much luck with them and Cat wasn't either. The slag was chewing up the seals pretty quick and all the oil would run out. It was a short time till the pins let go after that, so we were switching back to regular sealed links as soon as the SALT tracks were done. The boss up there took considerable heat from the company owner cause the D9's were down all the time and so brought in a Fiat-Allis HD-31 for a demonstration. It wasn't well liked, but did hold up fairly well with regard to the U/C. The slag was brought to the plant by end dump semi-trailers and piled up around back by the primary jaw crusher and magnetic separator. A Northwest 80D with a thirteen ton electro-magnet pulled the slag over a grid on top of the feed for the jaw, assisted by one of the Cat's. In that process a lot of steel and iron was pulled out and stacked off to the side, This was stuff that didn't melt in the blast furnaces at Zug Island, Trenton, and Ford's plant at River Rouge in Dearborn. The other stuff fell into the jaw, or was busted up by the crane with a Columbia drop cross of sixteen tons weight, then fed into the jaw after it would fit thorough the grid. You didn't stand or drive by that area when the crane was breaking slag with the drop-cross or the huge wrecking ball he also had. Pieces of razor sharp steel and iron weighing more than a hundred fifty pounds splintered off under the impact and would fly a hundred feet or more, busting everything in their way. The cranes had steel bars and thick pieces of crusher screen over the 1" thick armor plate glass windshields, even then, an operator got hurt once in a while. We had a huge weld shop there and maybe 6-10 welders on each of the first and second shifts. I had two on third shift, mostly just for emergency work and to repair truck beds and frames. They all stayed busy with bucket and dozer repairs, did a lot of hard facing and patching, and buildup work. This was just the truck and mobile equipment shop. The crushing and screening and conveyor shops also had a large number of people who did nothing but weld up and put stuff back together that the slag either broke or wore out. Conveyor belting went fast. The rollers wore out almost as fast. Jaws were welded on during third shift when the plant didn't run, also all day Sundays. Dozer wear edges were changed nearly every shift. Track shoe grousers wore out in about ten days, links lasted about twice that, we didn't bother turning them. We had a fleet of spare buckets for Cat 988B's and 992C's, also Hough 560's and H400's. Usually some stuff in for Cat 973 and 983 Steel Mill Special crawler loaders, though these were being phased out by then. Always a couple of buckets in the weld shop and several more waiting outside. The 992 buckets took a solid 6" thick cutting edge welded on solid. Took about eight shifts to prep and put these on. Then they lasted about two weeks, or as little as four hours. We bought truck loads of the edge stock from Bucyrus in twenty foot lengths and just hacked off what we needed. Needless to say, we got a good price on the edge stock you know. We rebuilt our own end dump beds too, both Euclid R35's and R50's. While I was in the Detroit shop the company bought twenty R35's from some quarry in Georgia. We stripped and completely rebuilt these rigs from the sandblasted and repaired and strengthened frames up. New cabs, new engines, rebuilt transmissions and differentials and all new hydraulics. The beds were gutted to the frame and damaged sections of that were replaced. New liners were installed of ¾" AR400 and oversized hoist cylinders and springs were installed. Then a paint job in Euclid green and a set of new tires. There are some other pretty abrasive materials out there, Scorie is one -- that's natural burned coal and dirt blended together. Volcanic ash is another. Some types of rock are pretty bad, copper slag is another real tough one. OK, enough for tonight.
This is an excellent thread gentlemen. I like to read these some what longer posts, with some story telling involved. I know some are reluctant to post much over a few sentences... fear of running on... but a little bit of story and background makes a good read, especially when done with at least a little bit of proper puncuation... doesn't have to be perfect... just readable. Don't discount d6peg theory about snow either. An old logger friend once told me that Cat had 3 rental rates. One for dirt, one for rock, and one for snow. The one for snow was the highest... of course, it was usually plowing snow, and that normally involved fast travel speeds... so I suppose Cat took that into consideration... although, just operating in snow has it's own set of problems... just ask KoO about track and sprocket packing. That's why the holes are in his pads. I've cut many a hole in ours when we were still logging. Again... good posts... I found surfer-joe's 2 posts especially informative, and very entertain to read. Thank you all, OCR
great writing joe!!! much to learn i have...
Joe, Great stuff. Your posts are always very informative and well written. Thanks! Tony
Good stuff Joe! Very informative. "Behind the scene's" are always interesting.
Around my parts the most abrasive material is chert. Chert is a quartz, limestone and clay mixture. We had a project with some rather deep cut 25-30FT deep. Chert also has beds of boulders, some as large as a VW Beetle. After a little time in the material, the track hoe was the only machine that was economical to excavate this material. Although bucket teeth would last a day and we would add old cutting edges to the buckets every 100-200 hours. You would have to rotate your teeth on the hoe at lunch break to get even wear. We had plenty of old cutting edges from the D8R we had rented and might I add renting a dozer in this material is the way to go, poor old D8 when it left there. A new set of pads on a D6N lasted 450 hours until we had to change them. One bright side to the ordeal was the chert only wore out what touched it, the pins/bushings and the rest of the undercarriage had normal wear. We used a 953 to spread the chert in fill areas and what you had to watch for was the bottom of the teeth wearing before the tips while spreading the fill. We wore through the factory wear plate on the 953 bucket in 200 or so hours. The old D8 cutting edges, 3 pieces welded across the bottom, held up pretty well and since the machine left that jobsite, are still in decent shape. It's not coral or slag, but by far the nastiest stuff we deal with.
I haven't run into anything as bad as the coral sand that Joe speaks of but we do have something kind of unique to this section of the country. We have glacial till in Washington State that really wears stuff out. I spent time in a couple of small coal mines and this stuff takes off cutting edges and undercarriages pretty fast, especially when its wet. It is full or siica and the clay holds the stuff together like lapping compound. When we started the second mine we were out of sync. The place opened in the fall and the wet hit us hard that year. The first undercarriage was gone by April and we put a new one on. That lasted good till fall but was gone this time in February. By April that next undercarriage was over half gone. Cutting edges on the grader only lasted a week, edges and corners on the dozers were turned between two and three weeks and changed at just a little over a month. Hard sandstone was underneath the till and we thought that would be more trouble but as soon as we started working it the steel life got considerably longer. Tires were just as bad. Our 773B trucks were pulling steep hills and running on the wet glacial till was just like running the tires against a grind stone. They would spin and you could just see the tread getting thinner. Tires had to be replaced twice a year. Good thread!
I've heard of Chert and have worked some in glacial till, anything with clay in it is bad as it tends to pack in everywhere you don't want it to. West Virginia and Kentucky have what is call sandrock. It can get pretty hard and is quite abrasive, but usually can be ripped easily and once exposed, it will deteriorate into sand over a short period of time. That's where I learned to ad the old edges to dozer faces. In the Denver area, I encountered a material called Denver Blue. It's a very dense and extremely hard material that looks like blue shale, but it's tougher than the hubs of hell and is not a good candidate for ripping. It's also extremely abrasive. We had a big Parsons ladder trencher there digging water and sewer lines and it was going thorough two sets of teeth a shift, in those days about 6-7000 bucks worth. You could always tell just where the trencher was by the big cloud of smoke coming off the teeth and the material as it was running. The excavators of the day wouldn't touch the stuff and we were too close to existing housing to blast. Our D9G wouldn't touch the stuff either. Over to Beatty, Nevada, just next to Death Valley we did some tailings ponds for a gold mine just outside of town. Most of the material there was not too extraordinary, but it was abrasive. The D9N we used to rip the cut areas was going through one ripper tooth every four hours. Couldn't pull two shanks, just the one and only down about 18" or so. Surprisingly, the tailings sand from the copper operation at Kennecott near Salt Lake City is destructive. But it's a combination of the sand with acid and water. The copper operation uses a lot of acid in their process to leech the copper out, the sand is then pumped in a very liquid state to the tailings ponds where the water settles out and is reused in the processing because it still hold a lot of copper. The acid however attacks any metal it comes into contact with, especially high tensile bolts. Aluminum just melts away in hours. Always had to be careful with the sand and water there, it would redden your skin in a few minutes and burn your eyes bad. GET would take a real nice shine that you could see yourself in, then be a solid coat of rust by morning. Working buckets and things in the acid water at Kennecott would, over a short period of time in certain sections of the mine, actually put a copper coating on the bare metal of the bucket where there wasn't any abrasion. Trash pumps here had to have stainless steel impellers, aluminum impellers disappeared in half a shift. Uranium tailings would do the same thing, shine up real bright, then rust overnight. Not real abrasive, but the acid was bad and quite destructive. It particularly liked to muck up anything electrical it came in contact with. Did a job in Northern lower Michigan one summer loading up milled asphalt off I-75. Used Deere 644 loaders and it was a fairly high speed operation. A blade rolled the material up into a windrow and I scooped it up from there and loaded it into OTR dump trucks. The bottom of the bucket wore very fast and at first, we were not using a bolt-on or weld-on wear edge on the lip. We learned quick however and spent a day in the shop drilling holes in a new lip that had just been welded on so we could bolt up a nice thick wear edge under it. That milled asphalt was very abrasive and the mill crew were changing carbide teeth pretty often.
Opearators are the worst of all on tracks, its all on how you run your tracks. Second would be Solid rock and snow/ice. Ice can wear down ice cleats faster than welders can put em on