Bad Welds?
- Thread starter Scm
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but WHO decided the 400KG spec ? Bet t was a committee decision,some wanted 350 ,others 450...so 400 was the 'compromise' . Odds are pretty good it wasn't a one person decision......
Yes, some undercut, but inspect any piece of machinery with numerous welds on it and see how many weld defects there are. Undercut may or may not be a problem since it will depend on whether or not the loads on the welded joint will result in a stress riser due to the undercut. The joint in question is primarily in torsion so the tension forces are parallel to the direction of the undercut.
Also, the torsion load is greatly affected by where the load is on whatever implement is on the end of the loader. If the load is evenly distributed the torsion is minimal. It's when the load is not evenly distributed on each arm of the loader that problems start to show up.
And I thought I was buying a "quality" product from a company that cares about the product they put out.. I should of just bought the cheaper Chinese tractor and expected this to happen.
I know you're being facetious, but post some photos of BX23 equivalent tractors and loaders from other manufacturers and see if they're doing anything different with their models. Loader design is well understood, and generally well executed i.e. the engineers are designing loaders for the intended use. I had a BX25, owned an MX6000HST and currently have an MX6000HSTC and M6060HDC and use the crap out of the loaders with zero issues in more than 10 years. Four Kubota loaders, zero problems.And I thought I was buying a "quality" product from a company that cares about the product they put out.. I should of just bought the cheaper Chinese tractor and expected this to happen.
Obviously QC could have been much better with your loader, but that comes down to the place where the loader is built, and of course oversight by Kubota to ensure that products are being made to their standards.
No, I would not call that compromise either. It is a business decision.
Marketing would typically decide. From what they hear from their sales network they would have discussions like: "it looks as if we have an xyz kg loader for the abc tractor this would fill a gap in our tractor range and also give us a loader to compete with manufacturer (add colour as required
)". They would most likely talk to engineering if this is feasable and then the specification would be written.If the owner exceeds this specification, as clearly noted in the user manual, and breaking the loader in the process, you cannot blame engineers or welding robots for that.
Of course the design can handle much higher loads than specified in the manual, but doing that increases the probability of breaking something.
If you have to lift xyz kg then buy a loader that is specified for that and it is highly unlikely that you will see a problem during its lifetime. Note that I wrote "unlikely" and not "never". There is no such thing as 100% certainty in engineering.
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I do love the tractor. Runs awesome, is strong. Just disappointed with this one thing.
And you have every reason to be disappointed. This loader should not have left the factory.
I had another look at your first post. It has been said most likely already (just not by me
) but the welds do not look like robotic welds to me. I worked in servodrive design used in robots and even the poorest servo system would have led to better welds.I think they were manual welds and the person either made a mistake or was not trained properly and the welds were not inspected properly.
Humans have to be avoided in a production process as much as possible. Visiting a Bosch production facility as students we were told that if you have only a single person in your production line your quality figures are down by a factor of 100, even with good, motivated and well trained employees.
Chanceywd
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Kubota L2501DT BH77 VIRNIG URG60-CT 1950 8N WC-68
late comer to this thread and will admit i didn't read every post about fish??..... but I thought those welds in torque tubes were considered "sacrificial welds" much like sheer pins are sacrificial.
I was taught the loader and tractor is protected from heavy vertical loads by the pressure relief valve.
For heavy twisting forces though like digging stumps with outer edge of the bucket, etc.... then to protect against damaging the really expensive stuff like loader arms, etc... these twisting forces break these welds first before damaging loader arms, etc...
I could be wrong but I was taught somewhere in my past that these torque tube welds are supposed to fail much like sheer pins.
I was taught the loader and tractor is protected from heavy vertical loads by the pressure relief valve.
For heavy twisting forces though like digging stumps with outer edge of the bucket, etc.... then to protect against damaging the really expensive stuff like loader arms, etc... these twisting forces break these welds first before damaging loader arms, etc...
I could be wrong but I was taught somewhere in my past that these torque tube welds are supposed to fail much like sheer pins.
I must say. I didn't see that coming.
Too bad it wasn't just pins that broke and not the whole unit.
You can’t tuna fish but you can tune up a dolphin… wait I think I said that wrong. I’ll be here all night.I prefer tuna.
And dolphin is a mammal, not a fish.
Usually when a weld breaks it's due to lack of penetration, either not enough heat or going too fast.
Welding same thicknesses of steel is fairly easy, it's welding say 1/8" plate to 1" sheet you HAVE to know what you're doing.
Welding same thicknesses of steel is fairly easy, it's welding say 1/8" plate to 1" sheet you HAVE to know what you're doing.
dirtydeed
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B2650 BH77, U27-4R2, BX23TLBM, box blade, rear blade, flail mower, Stump Grinder
Ya see, I just knew that my masters degree in Marine Science would be useful at some point in my life...I prefer tuna.
And dolphin is a mammal, not a fish.
That's how I roll too. Bad welds happen but I'll fix them myself. I bought a Kaufman gooseneck trailer last year direct from the factory, and the price was hard to beat, but I knew that I'd be doing some welding on it to get it to where I want it to be. The cross members pierce the 12" x 16lb I-beams that run the length of the trailer, but the C-channel cross members are only welded to the I-beams along the web of the channel. I'll fix that by welding the flanges as well which will add stiffness to the trailer. I'll be adding some steel in a few places no doubt.
I ordered a QH20 a few weeks ago and picked it up this week. I didn't have to pay shipping since the manager at the local Kubota dealer had it put in a container with other equipment that had been ordered. When I got it, the paint had been scraped/scratched off in a couple of areas but BFD! It's a tool that's going to see many, many years of hard use. We have people here complaining that their new bucket has some scratches on it.
"you can tune a file system but you can't tuna fish"
hpux user manual, tunefs command
Hmmm... something is not right here. Maybe @hagrid can explain what that has to do with bad loader welds.
Porosity, insufficient weld size, hydrogen embrittlement, slag inclusion, HAZ, insufficient filler material properties, rapid cooling, lack of preheat, ... there are many reasons or causes of weld failure.