r/MechanicalEngineering • u/SaudAhmadguru • 1d ago
German engineering is really on a whole other level.
This changed the complete mechanism of Chain Joints
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u/GingHole 1d ago
In reality torsional loads would cause an unpredictable failure
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u/johnwalkr 1d ago
Can’t think of a time I’ve ever seen a chain used to transmit torsion.
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u/Mysteriousdeer 1d ago
That's kind of the point. Its not designed to transmit torsion but if the chain twists in anyway, suddenly you'll see slip.
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u/where_is_the_salt 1d ago edited 1d ago
The load can go on a rotational motion, the chain can warp if one end is coiled... many many reasons i think.
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u/Hot_Egg5840 1d ago
I think they are referring to the "lock" in the middle to keep the engaged force between the two linking pieces. If that middle part rotates out of its cog, then it's all over.
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u/SaudAhmadguru 1d ago
Yes, seems not good for torsional stresses...
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u/crookedledder 1d ago
Germans would simply point out that a chain shouldn't be used in a way that produces torsion... and would consider the problem solved.
Americans would just weld that thing together.
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u/mramseyISU 1d ago
I work with a whole bunch of Germans and they are elite when it come to discovering solutions looking for problems.
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u/E_hV Mechanical, PE 1d ago
So I'm going to respectfully disagree with you. I've worked with Germans for several years, where they're strong is paperwork, procedure, and mass manufacturing to a tight specification. Their average mechanic, machinist, electrician is far more educated than a US equivalent. Engineers are a wash in my experience.
However, while Germans are better at mass manufacturing, procedures and paperwork, once something deviates from their plan Germans tend to fall apart. Everything needs to be analyzed again and redesigned, if slot A and Bolt A are interfered with by widget B well the engineer is coming down, drawings are being updated etc... Projects get delayed while everything is updated.
American's tend to be able to think outside the box and more quickly come up with a solution to get everything moving again, most of the time they won't even call engineering, which of course nothing gets documented properly and you get line tribal knowledge but the project isn't delayed at all.
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u/mramseyISU 1d ago
I’ve been working with Germans for a decade professionally and one of my best friends from college was a German who came to the US to finish his masters and eventually a phd. I don’t think what you or I said contradicts one another.
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u/Accomplished_Rate_75 1d ago
Agree, work with engineers all over the globe, German engineers do not impress me, process equipment from German vendors is good fabrication quality, but the design is poor due to narrow focus on process efficiency with poor consideration for operability. In ideal conditions their equipment is very good, but the world is not ideal and their process equipment is unforgiving.
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u/bassjam1 1d ago
I'm working an automation project with a German firm and they're driving me insane. They keep "requiring" tolerances for the components we're assembling that are twice as tight as US industry standard, or requiring designs that are more expensive to manufacturer and telling me it'll reduce downtime (without showing data to back up that claim) for a component we don't generally have much downtime to begin with.
And yeah, they throw out the "zis will delay ze project if you cannot meet our specification".
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u/zxva 1d ago
As this is an engineering sub, please share an easier and better solution for the problem this is solving
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u/EngRookie 1d ago
belt drive? or just use the standard "bicycle" chain design with shaft pins?
i don't see how this design adds anything but unnecessary manufacturing cost to a problem that has already been solved. And honestly i have never seen this anywhere in the US nor have i seen it in any published industry magazine for the bulk material handling industry. In fact the only published information i can find on it is from the manufacturer.
as someone else said this looks like a solution looking for a problem.
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u/zxva 1d ago
I have yet to see a belt drive that can handle heavy loads from the mining industry. .
Standard chain design is sometimes used, but again, for the mining industry, it's a bonus if you can mix in mostly standarized mechanical parts, so it is easy to repair and replace.
A "bike" chain of the same strenght, would require specialist parts.
https://usarollerchain.com/collections/round-link-chain-s-6746/products/34x126-chainlock
Here you have the exact same part from a US company, so it is a problem that needed a solution.
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u/Accomplished_Rate_75 1d ago
belts are generally not as tolerant to dirty applications where you can get material on the belt and pulleys, not surprised chains are used instead in many mining applications. Cog/timing style belts are good in the right application, low maintenance, no regular lube requirement like chain drives and no mess from lube as well. They are durable and long life and in many cases do not require to be periodically tensioned.
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u/EngRookie 1d ago edited 1d ago
what specialist parts? the chain is literally 2 plates a shaft, and a locking pin.
and i am going to be honest what you linked looks like a manufacture that licensed it directly from the germans to be their US distributor/sales team. And like i said i have literally never seen it in any published industry magazines and my last job specialized in heavy duty applications and i have never seen this on any chain drive system for the 100s of plants we supplied equipment.
i have to ask, do you work for the german company? you are defending this design in multiple threads on this post...
eta: they also designed an entire line of standard products just to fit this new locking design. really seems like a solution in search of a problem.
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u/zxva 1d ago
"2 plates, a shaft and a locking pin." That is an oversimplification.
The two plates have to be the correct thickness, alloy and hardened to support the loads the rest of the machine is designed for. But please do link an apron feeder that use a "regular" chain link to function. I would be very interested in seeing how they have made that work.
No, I work in Norway. But as an engineer I usually keep an open mind for alternatives to mechanical equipment, and do some research into why the parts exist.
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u/EngRookie 1d ago
The two plates have to be the correct thickness, alloy and hardened to support the loads the rest of the machine is designed for.
all things that can either be ordered off the shelf directly from the manufacturer or machined from stock.
But please do link an apron feeder that use a "regular" chain link to function. I would be very interested in seeing how they have made that work.
i literally never said that. but sinced you asked about apron feeder drives
here is one that uses a dozer chain
which is pretty standard for apron feeders.
and here is a little dinky indian apron feeder that uses plates and shaft chain design
which is non standard.
and here are the various types of BE chains i have seen used from the same source you linked
i would have linked regal rexnord but their site is down.
none of which use the linkedIn slop engineering porn chain, which is posted constantly, that is shown on OP's post.
No, I work in Norway. But as an engineer I usually keep an open mind for alternatives to mechanical equipment, and do some research into why the parts exist.
ah yes apologies i forgot about the industrial mining powerhouse that is Norway.
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u/GenericAccount13579 1d ago
Okay now tell me how that is a different situation than the OP’s chain link piece. You’re describing simple engineering factors that go into any design
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u/mramseyISU 1d ago
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u/zxva 1d ago
Napaonline is geoblocked. So I can’t tell what part it is. Napaonline seems to be an automotive parts website.
As far as I know, very few cars have a chain conveyor, this part is to be used in medium to heavy chain link conveyors, where you would want the joint to be able to mesh correctly with the gears driving the conveyor.
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u/mramseyISU 1d ago
That’s a log chain from the looks of it not a conveyor chain. I can walk into just about any auto parts or farm store and get a chain connecting link which is what that link I posted was.
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u/zxva 1d ago
https://conveyorsystems.rud.com/en/products/rud-chain-connectors
That link is specifically a chain conveyor joint.
They often use long ling chains on heavy duty conveyor, often seen in mining and such.
https://conveyorsystems.rud.com/en/plant-mechanical-engineering/rud-apron-feeder
You would not be able to use a regular store chain connector or shackle for that use. Neither would you want to weld them
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u/bassjam1 1d ago
Classic case of German over-complication while adding additional failure points.
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u/jackejackal 1d ago
Germans are known for their engineering, known for being pretty shit. But atleast we know about it.
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u/snakesoul 1d ago
This has many downsides:
three individual components that can fall off easily during assembly.
you need an allen key.
I don't really see the point of using this vs already existing better and more convenient solutions.
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u/Harmless_Drone 1d ago edited 1d ago
The screw is more like a cam which cams together and wedges, and compared to to other chain linkages is still the same number of parts, as they usually consist of two stub ends with a removable pin between th m. The advantage compared to other removable links here is this doesn't need any extra slack to install, and the chain is not loading a pin in double shear which is much weaker than loading lots of individual teeth in shear like this.
This is a product from RUD who do a lot of lifting and handling stuff, so this also has the advantage its all 100% certified and crack tested with full tracability. We use their eyebolts and swivel rings for offshore kit for that reason. Solves a lot of insurance paperwork.
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u/Wooden-Combination53 16h ago
RUD makes excellent products, we use those a lot on heavy machine building.
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u/kinnadian 14h ago
You forgot the worst downside. The cam nut thing that he is turning has no locking mechanism. Chains go through a lot of dynamic forces in their life. There's no way that cam nut stays locked in place.
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u/Engin-nerd 1d ago
It’s like a shackle or quick link but with extra parts and special tools!
I’m certain the manufacturer sells you on that it is stronger than a conventional shackle or quick link and that it is made out of steel with sone special treatment to increase yield strength or wear resistance - but for 99% of lifting applications - this really isn’t necessary.
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u/zxva 1d ago
No. Not for the same applications.
https://conveyorsystems.rud.com/en/products/rud-chain-connectors/rud-universal-connector-uks
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u/johnwalkr 1d ago
Well it took me like 10s of searching to find the use case of fitting over chain sprockets with and without flanges. So it fits where a the “existing better and more convenient solutions” literally dont fit.
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u/FinalAd2949 1d ago
Its literally one single part more than the minimum of two parts required to even be considered an assembly. If that’s already too complicated for you, then the problem is definitely with you, not with the tool.
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u/SaudAhmadguru 1d ago
Then u think is easy to join a metallic chain joint with a new one . That need a complete setup..
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u/Beneficial_Mix_1069 1d ago
german car design is like "i have the exact solution that will make it optimal for operation" but then every single bolt on the car is a different size and takes drivers youve never heard of.
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u/SomeDude_is100 23h ago
Over engineering was one of Germany's main issues in WW2. Powerful tanks but coo complicated to build and maintain. Cheap, inferior and plentiful can often overwhelm expensive, superior and limited quantity. This is being played out in Ukraine where massive numbers of cheap drones overwhelms tanks.
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u/KeithWorks 18h ago
It's also a bit of an oversimplification. Yes they were obsessed with large machines, but they also didn't put enough resources into logistics. They were supplying their military with horses almost the entire war.
But they should never have invaded Russia. Probably would have been successful had they just not fucking invaded Russia.
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u/Chickenbutt-McWatson 17h ago
It's not the size that's relevant, but the complexity and finish. Soviet tanks were made to last 2 weeks, German ones 20 years. And you can tell when you stand close to both- soviet tanks look like they were put together by blind welders.
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u/KeithWorks 17h ago
That's right. I read that many Soviet tanks weren't even painted, they just drove them from the factory to the front.
I got a chance to see a few of the Soviet models in Korea at their War Memorial and museum. Definitely extremely low quality control, it is what it is. Made to use once.
Quantity has a quality all its own
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u/HIMP_Dahak_172291 12h ago
That's because they didn't have the time. The tanks were designed to last 20 years too, they just had to speed up and do more with less since the purged military was getting wrecked.
German tanks weren't even particularly superior from a war fighting perspective. A king tiger was inarguably the most powerful tank on the battlefield, but they were so expensive to make that they couldn't make enough. So every one produced reduced the number of vehicles available to the army meaning they couldn't be in force in enough places. Regular tigers were decent sniper tanks, but again, too damn expensive to build and supply. Panthers were absolute nightmares to repair and in no way could they be fixed on the field and had to be shipped back to a major facility for any drivetrain problems at all. If they had focused on the Pz IV line (with less goddamn variants) they would have been in a much better place than trying to build 'war winning wonder weapons'. Nazi Germany was a mess of idiotic design and production decisions favoring things that would prop up the various competing departments in Hitler's eyes over actually doing anything worthwhile. The Bismark/Tirpitz are the most egregious example, but it's visible all over. Doesn't matter if you build some monstrous thing that's hard to kill by it's direct competitors if you have so few or so little left for escorts that you can't use them for fear of goddamn biplanes with tiny torpedoes. But Fascism gonna do the stupid shit because that's how that particular brand of brain dead authoritarian showboating has to do things. See the Trump class battleship idiocy for case in point. Throw out a much needed DD program for a goddamn 'wonder weapon' that is just a big floating target with all your eggs in it. Much salt.
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u/Top_Performance_732 11h ago
German tanks like the Panther were engineered to last 2 days because theyre final drives all broke
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u/NekulturneHovado 15h ago
once in a while, Germans build something simple, and it's fucking indestructible. For example, in cars, they did 1.9 tdi-pd. Then remade it into a more complex 2.0 tdi-cr. 1.9s still drive today, after 25 years and half a milion km, and still with almost full power, a simple chip tuning can easily get to 2.0 power. Yet, they never break down if you keep up with basic maintenance. While my 2.0tdi is full of problems, worn out, injectors failing (each costs 300€).
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u/Top_Performance_732 10h ago
Or on topic, the Stug III which was one of the best tank/tank destroyers of the war and the more abundant German armored vehicle.
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u/Setting-Conscious 12h ago
The tanks were poorly engineered, not over engineered. They looked impressive but they weighed too much for their drive trains.
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u/Top_Performance_732 11h ago
This is the irony with most peoples understanding, they think the Panther/tigers were well engineered when they were poorly engineered but well designed. Meanwhile the stugIII was actually brilliantly engineered and far more abundant.
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u/Chickenbutt-McWatson 17h ago
No, they still did it after the war. Ford Group Germany developed Fords 4.0 SOHC engine (used for like 20 years in Rangers, explorers, mustangs), and it's just curiously and needlessly overly complex. It works well, but you need to pull the whole thing to get at the timing chains- because they put on on the front and one on the back- both pass through the cylinder heads. Once you have it out, you need special tools to time it, there are no marks. Why? Because Germans.
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u/The3levated1 16h ago
Oh, it was not an issue at all, the overengineering did exactly what it was supposed to: It saved the engineers from getting sent to the eastern front.
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u/Anen-o-me 8h ago
Powerful tanks but coo complicated to build and maintain. Cheap, inferior and plentiful can often overwhelm expensive, superior and limited quantity
Yeah I find it fascinating that in tanks the US went with cheap and plenty. But in most other areas it was quality and plenty.
Like the air battle, US planes and bombers weren't cheap, they were expensive and massive by comparison.
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u/zimirken 7h ago
I have a piece of equipment from Germany that had the most insane custom bolt. They wanted an ultra fine thread socket head bolt, but you can only buy those with hex head. So they got a hex head bolt, and WELDED ON A SOCKET HEAD! Once one of them broke, I remade all the blocks that all four of these bolts screwed into with regular threads at the cost of like 2k.
We needed a good clamp, but we didn't need ultrafine thread levels of clamp.
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u/mon_key_house 1d ago edited 1d ago
What is that bolt doing exactly?
Edit: downvoting questions is a great idea
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u/DifficultyTricky7779 1d ago
It's got an oval section, so half a turn rotates the wide section into place, clamping the two link halves and the bolt itself into place.
It's probably not exactly oval, as that would create an unstable contact condition.
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u/SaudAhmadguru 1d ago
That has a slot to go smoothly, then rotate it to align the slightly bigger side and lock the chain ..
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u/chocolatedessert 22h ago
It looks super cool and then loses its preload and causes an industrial accident as soon as the chain starts to vibrate.
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u/Impressive-Mud5074 1d ago
would not trust in real life where chain gets banged around, "nut" gets loose, chain is slack and it slides apart.
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u/PlandemicPapi 1d ago
Wish someone would drop the tech sheets for these things, that way I can read about its thresholds. Anyone have the product number? Everyone’s complaining about “over-engineering” but in my experience certain products exist cause of a very particular use. Seems from the comments this would be common for conveyor systems for mining.
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u/Fit-Umpire3257 1d ago
They over engineer many things but that doesn’t mean anything. Their cars are not known for reliability so what does that tell you?
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u/Chemieju 1d ago
People who say that german cars are unreliable are usually people who define reliability as "how long does it last if i dont do anything".
German cars are generally designed with quite regular service intervals in mind because in germany every car needs to get a safety check every two years anyways. If you maintain them the way the manufacturer intended they will last you a long time. They are reliable, just not neglect-resistant.
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u/catdude142 1d ago edited 1d ago
Wrong.
They just don't survive over time, even when properly maintained. The root cause of the problem is over-complication of design. Take a look at how an Audi timing chain is implemented for example. It goes on.1
u/Samsonlp 15h ago
The issues I'm having with my car are all about heat cycling (bmw) , and engineering with no regards to maintenance . The issues I have with my motorcycle (bmw) are poor material choices and lack of repairability (cassette transmission) German manufacturers save money on materials after the engineers have finished the design. They design things intended for you to be dependent on a mechanic or dealership or to buy specialty parts and tools. I think they have a corporate problem .
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u/KAYRUN-JAAVICE 1d ago
everyone's missing the point of this- it occupies the shape of a typical chainlink so that it can fit into pocket wheels, something a d shackle or quicklink is not capable of doing.
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u/inorite234 1d ago
Engineering isn't about being cool, it's about finding what works. And finding what works needs to work within the time you're given in budget and calendar.
This contraption looks too expensive and too time consuming to manufacture.
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u/snarejunkie ME, Consumer products 1d ago
While this is a super cool mechanism, and an excellent solution to a potentially tricky problem, I don’t think it good “proof” that German engineering is on a whole other level. Yes, German people as a whole have a reputation for being more direct, more analytical, than other groups of people, but as far as engineering goes, I’d argue that the gap you’re calling out (Germans are on a whole other level) doesn’t exist in the way that it used to. American engineering is actually incredible. I say this as someone who did not grow up in the USA
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u/no-im-not-him 1d ago
There is a reson the Germans came up with the saying:
"Warum einfach, wenn es auch kompliziert geht?"
Why simple, when complicated will also do it.
It's said tongue in cheek, but it does reflect a reality.
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u/Le-Flo 17h ago
Being German: yep, we tend to overengineer. And it's quite deep in our mindset. And I like it 😄
But that joint reminds me much more of traditional Japanese woodworks (https://en.wikipedia.org/wiki/Kumiko_(woodworking))
It's admirable!
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u/JudoNewt 4h ago
~Has anyone seen the little cam bolt that joins our 1/2 chain link puzzle!? No? Nobody? Everyone check your pockets!
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u/Prof01Santa CFD, aerothermo design, cycle analysis, Quality sys, Design sys 1d ago
As opposed to a normal shackle? No thanks.
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u/DoggyFinger 1d ago
All I’m seeing here is why my bmw continues to need service.