Why are my deere 644 rims breaking?

funwithfuel said:

We've established repair is not an option, let's look for a cause.

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I get the impression that the OP was looking for confirmation of his opinion of a material/workmanship quality defect in the rims.
Now people are suggesting what would amount to undertaking a failure analysis - that doesn't exactly fit in with the original script. Miaybe it mght open a can of worms. My 2c.

There are dozens of companies specializing in repairing expensive alloy rims on passenger cars and trucks. Some wheels are well over $1000 each and can be repaired in a couple hours. They do a lot of work for insurance companies but not all rims can be repaired. I know a guy who started one of the first wheel repair businesses and sold it for a handsome profit several years ago. He currently specializes in aluminum fuel tank repairs on semi's and specialty work like aluminum radiators on motorcycles and snowmobiles that are paper thin.

Could a loader rim with 2 or 3 cracks be successfully repaired, I'd say yes but would require a very specific procedure and quality control measures. Would depend on the cost of a new rim to determine if it was cost effective to repair.

As for the OP's rim it may have just been too light of rim for his application. We don't know if the bolts came loose or some other factor(s) contributed to the cracks. If a repair was attempted and a reinforcing ring from the bolts to the outside diameter was added to make it similar to the HD rim I think there is a good chance of a successful repair.

Welder Dave said:

Have seen valve stem holes welded and new holes drilled in Alcoa rims by a specialty welding shop several years ago.

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Arconic is the Alcoa wheel company

https://www.alcoawheels.com/alcoawheels/catalog/pdf/2017_service_manual_english.pdf

We aren't talking about a passenger car wheel carrying a thousand pounds of load, fifty PSI of air pressure and at most a few cubic feet of air. A loader or off highway truck wheel of the type posted can have forty thousand pounds of load applied by the boom and bucket while digging material, runs between seventy five to more than a hundred PSI and may have more that a hundred cubic feet of air inside it. Because of the possibility of catastrophic failure with the associated risks of damage to people and property outside of just the machine, the general consensus in the industry is that broken wheels don't get repaired, they get replaced.

As far as the Arconic wheels it could be that someone inexperience tried to repair a wheel and it failed which is why it is no longer allowed. It was quite awhile ago when it was common practice to drill new valve stem holes and weld the old ones up. The place I saw it done did a lot of specialty aircraft welding as well so were very qualified in aluminum welding. They welded a lot of aluminum oil pans too which could be tricky and full of impurities. I think Cummins were the worst.

Most of the time a wheel probably should be replaced. Most construction operations aren't going to have the skills or facilities to properly repair a wheel. There also isn't a governing body for wheels to insure strict repair procedures and documentation is followed. A lot of wheels are welded structures to begin with so with a proper procedure and strict quality control it is not inconceivable that a wheel could be repaired and/or strengthened. Knowing what caused the damage would help in assessing if a repair might be feasible. If a wheel is full of spider cracks obviously you'd replace it. If a wheel has 2 or 3 cracks because of a loose bolt or other obvious reason, a repair may be an option by someone qualified. Like I said previously, if the wheel was treated as a pressure vessel and repaired similar to a pressure vessel, repair could be an option.

Welder Dave said:

As far as the Arconic wheels it could be that someone inexperience tried to repair a wheel and it failed which is why it is no longer allowed. It was quite awhile ago when it was common practice to drill new valve stem holes and weld the old ones up. The place I saw it done did a lot of specialty aircraft welding as well so were very qualified in aluminum welding. They welded a lot of aluminum oil pans too which could be tricky and full of impurities. I think Cummins were the worst.

Most of the time a wheel probably should be replaced. Most construction operations aren't going to have the skills or facilities to properly repair a wheel. There also isn't a governing body for wheels to insure strict repair procedures and documentation is followed. A lot of wheels are welded structures to begin with so with a proper procedure and strict quality control it is not inconceivable that a wheel could be repaired and/or strengthened. Knowing what caused the damage would help in assessing if a repair might be feasible. If a wheel is full of spider cracks obviously you'd replace it. If a wheel has 2 or 3 cracks because of a loose bolt or other obvious reason, a repair may be an option by someone qualified. Like I said previously, if the wheel was treated as a pressure vessel and repaired similar to a pressure vessel, repair could be an option.

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I have seen pipe welders repair things I thought impossible to last. They proved me wrong. The overlay in the picture I posted was done by me. Never had a failure. That machine lives in a cow pasture. Would not do that repair for this 644 unit or only until a new rim came in.
Insurance companies are really tightening down on what you do and what they will insure.

From a metallurgical and fabrication viewpoint a repair could be possible but could require a Weld Procedure Qualification from an engineer and third party inspection to be certified fit for service. I think the same could be applied to welding on a ROPS. Crane booms are extremely critical and they can be repaired if proper procedures are followed.

I repaired bogie assemblies for a roller coaster that 3 people were killed on. A 3rd party inspector watched me do it. They were originally sent out and the shop did a terrible job on them. Looked like a 1st. year apprentice did them. Welds didn't even go fully into the corners. The inspector agreed with me they weren't suitable to put back on. Oddly enough an engineer was working on a weld procedure in case more had to be repaired in the future and could be done in-house. When the procedure was established the engineer was quite pleased that the one I repaired was done the way his procedure specified. Namely that a 6010 root pass was put in for max. penetration followed by a 7018 cap. It was then Mag particle inspected. I'd consider a roller coaster a pretty critical application. Below is an example of what can be done when proper procedures are followed.

https://wheco.com/projects/roll-over-protection-system-rops-repair/

It's the manufacturers that prohibit any welding on a ROPS structure. The government regulations only require an AWS certification to be able to weld on the structure. An MSHA inspector seeing any welding on a ROPS will have the machine locked out and the machine owner will be fined and may be charged with a willful violation. Any accident which results in harm to personnel as a result of modification from factory original configuration will be deemed a willful violation and can result in criminal charges and penalties.

Only certain types of damages to crane booms can be repaired. Any damage to a cord requires that section to be scrapped. Damaged lacings on tubular booms can be replaced following the manufacturers published procedures. Angle iron booms had no specific requirements when I worked on Koehrings. No specific certifications were required by Link-Belt when I was working for them. I carried a certification for structural welding at the time and was considered qualified by the dealer I was working for.

I would think an engineer approved repair procedure with all the documentation would hold a lot of weight. The example I found above is an example of that. The fact is, depending on the degree of damage, crane booms can be repaired. Huge draglines have welding cables running up the boom for doing repairs. Tubular booms were often filled with nitrogen and would set off an alarm if they leaked, indicating a crack.

An engineer who signs on a repair procedure has to own that repair for its life. That's why that have to pay for professional insurance. Would you think an engineer would sign off on a procedure for repairing a wheel? Have you repaired a crane boom? Have you ever worked with a structural engineer who designed a repair for a ROPS or a crane boom?
Apparently you are talking from an assumption of what you have heard or read.

I worked with a structural engineer welding amusement rides and other structural repairs in one of the biggest malls in the world. A competent engineer wouldn't have a problem standing behind his repair procedure. I would think an amusement ride would be considered one of the most critical applications to have an engineer involved.

Welder Dave said:

I would think an engineer approved repair procedure with all the documentation would hold a lot of weight.

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Unless the engineer was authorized by the equipment manufacturer to sign on their behalf whatever he certified wouldn't carry much weight in my field of work (that may not apply in other fields). What happens if he moves to another company or even dies..? Who stands behind the repair then..? Can't sue a dead guy, right.? That's the difference IMHO in having something that says "certified to be in compliance with ISO standard J3406 by Caterpillar Inc." vs "certified by Joe Blow, PE registration XXX".

The example of a ROPS repair that you linked was a specific repair/rebuild of a structure installed on a machine that was no longer in production, the article says as much. I can tell you now that if any large mining company was the owner of that machine it would have been sent to the scrap heap rather than repair/rework the ROPS.

I think what it all boils down to here is the difference in interpretation between what is "possible" (pretty much anything if the technology/engineering is available), and what is "practical" (in terms of "How much".?). You're putting forward the position that most all things are technically possible, and I don't disagree with you. However just because something is technically possible should not be taken as a justification for actually doing it.

Sure wheels can be fixed, sure ROPS can be reworked. But in all the opinions put forward the evaluation of risk versus return has never been put front and centre. Most large industrial organizations (and their insurers) take a very much risk-averse position when it comes to repairs like this, and that has nothing whatsoever to do with whether or not the repair is feasible from a technical standpoint.

I've been saying all along it could be possible and an engineer could consult with the wheel OEM. For the wheel in question, if the damage shown is the full extent of damage, the wheel may be able to be repaired successfully if it was also reinforced to be similar to the HD wheel. Knowing if the damage was from an overloading condition or loose bolts would be beneficial to determine if repair could be an option.

New bogie assemblies could have been built for the roller coaster (the bogies were specially built after the accident) but an engineer approved a procedure for repairing them. Three 2000lb. roller coaster cars connected together pulling better than 5G's with 12 passengers on a daily basis is a pretty critical application. Used to use 4 cars and I think pulled better than 7G's. but reduced to 3 cars after the accident.

that must have been the WEM mindbender. i remember back when that fatality happened and wondered what had caused the failure

Yes, the Mindender. Several factors caused the accident. They were running late that day and didn't do a full inspection on the coaster before the park opened at 10am. Otherwise they would have discovered the nuts on the basement floor. Another major gaff was that the German maintainence manual was never converted to English. I had heard it almost bankrupt the mall. It probably should have. New bogie assemblies were specially made that used castellated nuts with cotter pins so the wheels couldn't come loose. The designer of the coaster suffered a heart attack when he heard people had died on his coaster. After the accident very stringent inspection requirements were put in place for amusement rides. They were enforced by the same branch that did elevators and escalators. Before that there wasn't really a governing body for amusement rides.

I wouldn't have a problem with a repair on that type of wheel. We weld up the bead on loader rims all the time. when we first started buying maintainer graders, those type of wheels were not easy to get, and we built a few sets with custom centers. Anything that hits the asphalt would have a new wheel for sure

I used to see that same thing about ten to fifteen years ago. Add wheel loader center pins every 5,000 to 6,000 hours. In the last five years I've been seeing a heck of improvement in the Deere product line across the board. Wheel loaders in dairies were a big surprise when I was inspecting machines that had in excess of 20,000 hours on the clocks. They all had a lot wrong with them, but so did the Cats and Komatsu loaders. None of them had bad hitches either. I don't know what it cost to get that many hours but I was surprised at them getting there at all. A lot of the large construction customers use all small Deere dozers in their fleets. The operators like the visibility under the back of the blades and the feel of the load being pushed. Undercarriage life was still an issue though.

Theyd be in the bin ,If you were to weld and they failed ,injuries occoured you would in deep s#*t

pedrocar said:

Theyd be in the bin ,If you were to weld and they failed ,injuries occoured you would in deep s#*t

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Agreed. That was what most of us with industry experience were trying to point out.