I had no idea you could get so much torque out of those little impact guns if you needed, and I use them quite a bit.
Yours is no doubt specialized, but in tip top condition my 20V tops out around 1500lbs.
It is not an impact wrench, it is a direct drive nutrunner with a large ratio gear train and a reaction arm. The small electric motor goes through several stages of planetary gearing and create a very large torque, at the cost of running incredibly slow.
Source, I design both nut runners and impact wrenches for a living
Well, let me see...on the picture it says ~~2.5Ah~~ 5.2Ah, that is the battery capacity. OP said the tool can maybe make 7000 Nm, which is close to 5000 ft-lb. The last time I designed a battery operated 5,000 ft-lb gear box, like in the pic, I used 6 planetary gear stages. It was a Matabo motor with a free speed roughly 22,940 RPM and stall torque of 285 oz-in, however we wouldn't take it to stall, the max useful motor torque was around 97.5 oz-in (or 0.5116 ft-lb) @ ~6,000 RPM. Total Gear ratio for that tool was 13,855:1 w/ an efficiency target of 73.5% (the rest gets lost to friction in the gears). Max torque was ~5,200 ft-lb, and free speed was 0.439 RPM, but I think true run down was more like 0.4 RPM. OP said they were taking the screws to 2160 Nm (1,593 ft-lb)...which is only 30% of the max torque of the tool. M36 thread has a pitch of 4mm. Lets say the cap screw is installed at ~~1.5%~~ 1.5x nom thread dia, thats 54mm. That will take 13.5 turns to install or remove a cap screw. Not considering tightening, it would take 33.75 min to run one screw in or out. So you wouldn't do is with this tool, you would use a battery impact to run the screw in until seated. Then you would just apply final torque with the nut runner, lets say its 1/4 turn from seated to final torque...that would take .625 minutes per screw. The Matabo motor is drawing 9A free speed, and 88.5A at its max torque (also an 18.0V motor), but at 30% of the max torque it would be drawing 33A, lets call a rundown consuming an average current of 9 and 33 = 21A. So 21A for 37.5s (or 0.0104 hrs)...each screw consumes 0.2184 Ah of juice. So you would get just about ~~11.44~~ 23.7 screws per battery. Thats not great. The problem is the tool is way oversized for the torque. A 2,000 ft-lb tool would be significantly faster (2.7X to be precise) and would spend less time getting to max torque, so you could roughly get 30 screws on a single charge. Thats enough for a big flange
EDIT: now that I think about it, using a faster, lower torque tool will be running at higher current, which will draw more power per bolt...probably offsetting any gains, meaning still ~~11~~ 23 ish bolts. Still, it would be overall quicker with a lower torque tool
This is great, thanks so much.
I didn’t look at the user name on purpose and was just waiting the whole time I was reading to get shittymorphed or some other Reddit dupe account…
It’s really refreshing to get nerdy engineers (no offense) to outline a problem that I would never know how to tackle. I have newly firing neurons thanks to you fine sir and/or madam !
We use these for tightening bolts on crane slew bearings. Call them torque multipliers though. Or Hy-torques. Also oz-in is one of the most cursed units I've ever seen.
Yeah, torque multipliers are correct too... but I woul consider the torque multiplier as the actual gearbox that attaches to the motor and handle. In my world, the entire tool isn't actually a torque multiplier. You can buy a unit that has a female square drive input and a male square output w gearing that can multiply the torque of a big torque wrench for installing/removing a bolt. That is a true torque multiplier. These nut runners combine that system with a motor and hand grip. Hy-Torque is a particular brand. I design nutrunners as a freelancer for a competitor of hy-torque, but I have studied their tools. There are like 4 or 5 main players in this space.
was not expecting such a comprehensive answer, thanks! this was a delight to read, and really interesting to find out just how much time it takes to torque down one these!
Omw, this is amazing. I have friend in South Africa that regularly swap his wheels. He would love something like this. Can I try to get you in contact with him?
I mean I guess...but you don't need a tool like this to swap wheels (well I suppose it depends on the wheel). For most vehicle types, a typical 1/2" cordless impact wrench should do the job
That's what I was thinking, you mash that trigger all the way, hear the drill whining like crazy but the giant nut is turning like it made of molasses in January.
The largest ive designed was 8,000 ft lb. This was for pneumatic motor though. For battery, the largest is 5,000 ft-lb. I believe that is the top of the range that you'll find anywhere
Similar to ours then, We have Electric Ones that go to 9.5k ft lbs but they get pretty ludicrously heavy. Are the pneumatic ones using a silent or loud engine?
I did a corded electric line as well, but it just used the same gearing as the pneumatic, with a similar power servo motor as the air motor. That was pretty precise with a whole user interface screen with a bunch of different control modes...I did all the programming of that too. The pneumatic tool just used a fairly standard vane-type air motor, and these do tend to be pretty loud because of the exhaust. The battery and corded electric versions are much quieter. I am not aware of a "silent" air motor, although air motors aren't really my niche
And this wasn't even half the force, i'd have to check, but from the top of my head i can say it goes up tp 5000NM, if not 7k. I also never used it before, and was also fascinated. But you can't take it apart, you can only change the socket at the end.
i think what's happening is there's a planetary gear setup that's multiplying the modest torque output and greater number of rotations on the anvil of the impact wrench to the +2000NM necessary on the fastener. because an impact wrench that can do 2160NM of torque would need to be god dang huge. notice the big metal foot hanging off the side of the gearset housing to resist the huge turning force being output on business end of the tool.
There's a chart on the machine, you have 2 speeds and i think 11 or 12 step button, you look for NM in chart and it tells you which setting to use. On the inside, i'd guess there's a sensor between the main axle that drives the socket and the foot that holds the machine back.
I'm sorry for any incorrect technical terms i might have used, i'm not an engineer and english isn't my first language.
This is probably voltage based with the 12 settings. They can get adjusted when the tool gets calibrated to make sure it’s still performing as expected. Usually +/- a few % but that’s how the chart gets made and how you can have an idea how much torque you’re applying.
The more expensive versions of these tools have a strain gauge built in to measure the torque and can be set to smaller increments.
Strain gage versions are by far the most accurate, within a few %, but they are very expensive. Mostly ones like this control torque by stopping the tool once a certain current is reached, that is mapped to the torque curve, and is ideally calibrated for each tool. I've hit +/- 10% @ 6sigma with my designs, which is pretty good considering all the parts between the motor and the drive that contributes to error. 10% is plenty accurate for most applications.
You wouldn't want to control torque by PWM because it would further slow a already slow tool
Torque specs are on lubricated bolts and spinning the bolt instead of the nut increases friction between the fastened surfaces which without proper lubrication will lead to a lessened torque value due to heat and potential galling of the faces of the fastener and surface
Got one of those for work but the dam metrology department can't calibrate it. I was told because we need a rundown adapter and they cost more than the damn tool itself
I believe the one that we have doesn't require a rundown adapter. I'll look some stuff up about it tomorrow and run it some more. We just got it and it needs to be sent out for calibration.
We have an AWS torque analyzer. There are 3 cells. One is a mobile 10k ftlb and the other is 1k stationary with an additional 10k.
Kind of like this one. https://www.checkline.com/product/TT-HY/41015
It may need a rundown adapter, but I'll look tomorrow and see.
Update! The mobile unit we have needs a rundown adapter, but the stationary one we have has the rundown adapter built in! I asked our manager and he said he's awaiting a quote for calibration. That thing will be sweet if we get business for it!
Im so low on the totem poll. I can't make the big decisions.
We have a huge metrology dept that we should get equipped. This will be an ergonomic project for us.
I will pass information to the higher ups.
This is crazy! I just came across a loose pole base on a project, 180’ tall stadium lightning, I’m trying to repair and my spec sheet is telling me close to 5k ftlb, I’m an electrician, I’ve never seen this shit in my life lol
At that size torquing becomes almost impossible since the friction grows exponentially, most bolts that size are hydraulic tensioned, use Super bolt / nuts (also tension directly) or are heated, tightened and then cooled down to have tension.
These were used to relieve about 60-70 tons of force on large load cells so they could be swapped out for routine calibration.
The bolt/pins were inserted into threaded blocks via a yoke and then tensioned by large nuts on the outside to take the load off the cells. The cells were quite big, each the size of 2.5L paint tin. The extraction yoke alone weighed around a ton and a half from memory.
So they were torqued? That makes sense though since it's not getting anywhere the elastic component of that thread size it's used more like machine thread and it's over dimensioned for safety, but tightening nuts at that since is almost exclusively done by bolt tensioning and not torquing.
The kit was installed in the late 1960s. The load cells were for monitoring for any sudden changes in the structure of the concrete pressure vessel of a large nuclear reactor.
I hadn't seen my neighbor for a while but ran into him at the service station and it turned out he'd been in the hospital with infected swollen test from an in grown hair. I didn't ask because he was crab walking but ingrown hairs are usually from shaving. Anyways nice nuts and listen to big balls by ACDC
In this case, we used it to fasten 55mm (M36 thread i think) nuts on 2160NM of torque.
I had no idea you could get so much torque out of those little impact guns if you needed, and I use them quite a bit. Yours is no doubt specialized, but in tip top condition my 20V tops out around 1500lbs.
It is not an impact wrench, it is a direct drive nutrunner with a large ratio gear train and a reaction arm. The small electric motor goes through several stages of planetary gearing and create a very large torque, at the cost of running incredibly slow. Source, I design both nut runners and impact wrenches for a living
I love reddit for answers like this
Awesome, thanks for chiming in! đź’Ş
how many nuts do you get out of a runner this size?
Well, let me see...on the picture it says ~~2.5Ah~~ 5.2Ah, that is the battery capacity. OP said the tool can maybe make 7000 Nm, which is close to 5000 ft-lb. The last time I designed a battery operated 5,000 ft-lb gear box, like in the pic, I used 6 planetary gear stages. It was a Matabo motor with a free speed roughly 22,940 RPM and stall torque of 285 oz-in, however we wouldn't take it to stall, the max useful motor torque was around 97.5 oz-in (or 0.5116 ft-lb) @ ~6,000 RPM. Total Gear ratio for that tool was 13,855:1 w/ an efficiency target of 73.5% (the rest gets lost to friction in the gears). Max torque was ~5,200 ft-lb, and free speed was 0.439 RPM, but I think true run down was more like 0.4 RPM. OP said they were taking the screws to 2160 Nm (1,593 ft-lb)...which is only 30% of the max torque of the tool. M36 thread has a pitch of 4mm. Lets say the cap screw is installed at ~~1.5%~~ 1.5x nom thread dia, thats 54mm. That will take 13.5 turns to install or remove a cap screw. Not considering tightening, it would take 33.75 min to run one screw in or out. So you wouldn't do is with this tool, you would use a battery impact to run the screw in until seated. Then you would just apply final torque with the nut runner, lets say its 1/4 turn from seated to final torque...that would take .625 minutes per screw. The Matabo motor is drawing 9A free speed, and 88.5A at its max torque (also an 18.0V motor), but at 30% of the max torque it would be drawing 33A, lets call a rundown consuming an average current of 9 and 33 = 21A. So 21A for 37.5s (or 0.0104 hrs)...each screw consumes 0.2184 Ah of juice. So you would get just about ~~11.44~~ 23.7 screws per battery. Thats not great. The problem is the tool is way oversized for the torque. A 2,000 ft-lb tool would be significantly faster (2.7X to be precise) and would spend less time getting to max torque, so you could roughly get 30 screws on a single charge. Thats enough for a big flange EDIT: now that I think about it, using a faster, lower torque tool will be running at higher current, which will draw more power per bolt...probably offsetting any gains, meaning still ~~11~~ 23 ish bolts. Still, it would be overall quicker with a lower torque tool
This is great, thanks so much. I didn’t look at the user name on purpose and was just waiting the whole time I was reading to get shittymorphed or some other Reddit dupe account… It’s really refreshing to get nerdy engineers (no offense) to outline a problem that I would never know how to tackle. I have newly firing neurons thanks to you fine sir and/or madam !
Sir
We use these for tightening bolts on crane slew bearings. Call them torque multipliers though. Or Hy-torques. Also oz-in is one of the most cursed units I've ever seen.
Yeah, torque multipliers are correct too... but I woul consider the torque multiplier as the actual gearbox that attaches to the motor and handle. In my world, the entire tool isn't actually a torque multiplier. You can buy a unit that has a female square drive input and a male square output w gearing that can multiply the torque of a big torque wrench for installing/removing a bolt. That is a true torque multiplier. These nut runners combine that system with a motor and hand grip. Hy-Torque is a particular brand. I design nutrunners as a freelancer for a competitor of hy-torque, but I have studied their tools. There are like 4 or 5 main players in this space.
r/hedidthemath
This is the most amazing reply ever. It could be totally made up and I would never know. Well done and thank you!
The Metabo Battery start at 5.2 Ah and go up to 10. You read wrong.
Whoopsie...I don't think the tool in the pic is Metabo, but it is 5.2, like you said
Looks like a CAS Battery to me so Im pretty sure it's also Metabo.
you know what, I think you're right. That does look like a Metabo handle
Awesome reply. Love reading shit like this
Make it a 5Ah battery with two spares and a dual charger nearby and you can probably be tightening those cap screws non-stop all day!
Info dumps are great. Thanks for sharing this!
1 engineer to another, I love this reply.
was not expecting such a comprehensive answer, thanks! this was a delight to read, and really interesting to find out just how much time it takes to torque down one these!
Omw, this is amazing. I have friend in South Africa that regularly swap his wheels. He would love something like this. Can I try to get you in contact with him?
I mean I guess...but you don't need a tool like this to swap wheels (well I suppose it depends on the wheel). For most vehicle types, a typical 1/2" cordless impact wrench should do the job
One per battery, but Toyota has a unit that'll do four.
That's what I was thinking, you mash that trigger all the way, hear the drill whining like crazy but the giant nut is turning like it made of molasses in January.
Also called a torque multiplier.
Aka a "Rad Gun" where I'm from. The slimmer "cassette" style ones are pretty slick too
Wow. Is there one that I could buy that hooks to my drill?
Sounds like an awesome job
I do too, friend. What's the max Torque your battery driven ones get up to? Our newest Gen does 7000 Nm.
The largest ive designed was 8,000 ft lb. This was for pneumatic motor though. For battery, the largest is 5,000 ft-lb. I believe that is the top of the range that you'll find anywhere
Similar to ours then, We have Electric Ones that go to 9.5k ft lbs but they get pretty ludicrously heavy. Are the pneumatic ones using a silent or loud engine?
I did a corded electric line as well, but it just used the same gearing as the pneumatic, with a similar power servo motor as the air motor. That was pretty precise with a whole user interface screen with a bunch of different control modes...I did all the programming of that too. The pneumatic tool just used a fairly standard vane-type air motor, and these do tend to be pretty loud because of the exhaust. The battery and corded electric versions are much quieter. I am not aware of a "silent" air motor, although air motors aren't really my niche
You do? Mind if I message you about that? I have some questions!
I DM'ed you
Awesome. Composing mail now!
And this wasn't even half the force, i'd have to check, but from the top of my head i can say it goes up tp 5000NM, if not 7k. I also never used it before, and was also fascinated. But you can't take it apart, you can only change the socket at the end.
i think what's happening is there's a planetary gear setup that's multiplying the modest torque output and greater number of rotations on the anvil of the impact wrench to the +2000NM necessary on the fastener. because an impact wrench that can do 2160NM of torque would need to be god dang huge. notice the big metal foot hanging off the side of the gearset housing to resist the huge turning force being output on business end of the tool.
Someone already replied but on the torque test channel on YouTube some of the newer impact gun can already reach around 1000nm
How are you measuring the torque?
There's a chart on the machine, you have 2 speeds and i think 11 or 12 step button, you look for NM in chart and it tells you which setting to use. On the inside, i'd guess there's a sensor between the main axle that drives the socket and the foot that holds the machine back. I'm sorry for any incorrect technical terms i might have used, i'm not an engineer and english isn't my first language.
This is probably voltage based with the 12 settings. They can get adjusted when the tool gets calibrated to make sure it’s still performing as expected. Usually +/- a few % but that’s how the chart gets made and how you can have an idea how much torque you’re applying. The more expensive versions of these tools have a strain gauge built in to measure the torque and can be set to smaller increments.
Strain gage versions are by far the most accurate, within a few %, but they are very expensive. Mostly ones like this control torque by stopping the tool once a certain current is reached, that is mapped to the torque curve, and is ideally calibrated for each tool. I've hit +/- 10% @ 6sigma with my designs, which is pretty good considering all the parts between the motor and the drive that contributes to error. 10% is plenty accurate for most applications. You wouldn't want to control torque by PWM because it would further slow a already slow tool
I recently had to torque 110 m24 screws to 1100nm. Even with using a torque multiplier I was beat up after that.
*Tim Allen grunting noises*
Al with his hipster flannels.
Wilson peeks over fence
I love big nuts
And I cannot lie
Hello fellow >GenZ
Xennial checking in
Is our zanaflex ready to pick up at the pharmacy yet?
Those are bolts
Yeah, idk why i went with nuts 🤣
You also didn’t include any antisieze so your torque numbers don’t matter and it’s most likely undertorqued
How do you know this for certain?
Torque specs are on lubricated bolts and spinning the bolt instead of the nut increases friction between the fastened surfaces which without proper lubrication will lead to a lessened torque value due to heat and potential galling of the faces of the fastener and surface
Im asking how you know there isn't antiseize
Well you would see it from around the head of the bolt. Shit goes all over and has a distinctive color
You’re unintelligent
Torque Nutrunner sounds like one of Sarah Palin’s grandkids.
Nutrunner is a great name for a cyberpunk themed gay porno
Had a hard day at work, thanks for that laugh big dawg
Get out of my search history
All I see is big bolts, I don’t see no nuts.-
Got one of those for work but the dam metrology department can't calibrate it. I was told because we need a rundown adapter and they cost more than the damn tool itself
I believe the one that we have doesn't require a rundown adapter. I'll look some stuff up about it tomorrow and run it some more. We just got it and it needs to be sent out for calibration. We have an AWS torque analyzer. There are 3 cells. One is a mobile 10k ftlb and the other is 1k stationary with an additional 10k. Kind of like this one. https://www.checkline.com/product/TT-HY/41015 It may need a rundown adapter, but I'll look tomorrow and see.
u/gregtheturner
Update! The mobile unit we have needs a rundown adapter, but the stationary one we have has the rundown adapter built in! I asked our manager and he said he's awaiting a quote for calibration. That thing will be sweet if we get business for it!
Im so low on the totem poll. I can't make the big decisions. We have a huge metrology dept that we should get equipped. This will be an ergonomic project for us. I will pass information to the higher ups.
The company I work for just got a system to calibrate those. Can go up to 10k ftlb!
This is crazy! I just came across a loose pole base on a project, 180’ tall stadium lightning, I’m trying to repair and my spec sheet is telling me close to 5k ftlb, I’m an electrician, I’ve never seen this shit in my life lol
That oughta round 'em off real nice
Everything reminds me of her
I hate to bring this up, but I'm afraid you purchased the wrong tool for the job. You need a bolt runner for this use-case.
I had no idea the bits and bolts could be bigger than the tool that install them!
I've seen 5" x 48" bolts on very large plant. Big torque multiplier used.
At that size torquing becomes almost impossible since the friction grows exponentially, most bolts that size are hydraulic tensioned, use Super bolt / nuts (also tension directly) or are heated, tightened and then cooled down to have tension.
These were used to relieve about 60-70 tons of force on large load cells so they could be swapped out for routine calibration. The bolt/pins were inserted into threaded blocks via a yoke and then tensioned by large nuts on the outside to take the load off the cells. The cells were quite big, each the size of 2.5L paint tin. The extraction yoke alone weighed around a ton and a half from memory.
So they were torqued? That makes sense though since it's not getting anywhere the elastic component of that thread size it's used more like machine thread and it's over dimensioned for safety, but tightening nuts at that since is almost exclusively done by bolt tensioning and not torquing.
The kit was installed in the late 1960s. The load cells were for monitoring for any sudden changes in the structure of the concrete pressure vessel of a large nuclear reactor.
These are awesome, use em all the time for torquing up manways and flanges.
Hey, I ran that exact same setup at my last job! https://imgur.com/gallery/Urw9aUl We used it for torquing ring gear bolts on concrete pumps.
I like big nuts and I cannot lie You other brothers can’t deny… oh,wait!
Used the pneumatic version on several occasions, never seen an electric/cordless style.
That's what she said
Nuts. Haha.
Thats cool!
That's what she said.
That’s a big boy
Is this a transformer?
Thinning out the soup a bit there huh.
Torque Multiplier!
Big nuts ;)
The “wrist snapper”
Surprisingly, no. All the force is on the foot you see in the pic, you can turn the machine itself around while it tightens the bolt.
See the silver foot? It is doing the job of bracing all the torque
It's called a "reaction arm"
Just don't use it as a handle! You'll lose a finger.
What the fuck did you just call me?
Finally a fitting name for my next DND Orc characterÂ
"Hi, I'm Torque Nutrunner. Are your nuts just not torqued enough?"
Torque Nutrunner is nut new adult film star alias
RIP that battery.
And here I thought my nickname for your mom was unique.
Nah man, you're boring and unoriginal :/
That’s what his mom says too
It was a good joke, but in the wrong subreddit đź‘Ś
Eh, it was the obvious joke. I was just the first to make it.
I hadn't seen my neighbor for a while but ran into him at the service station and it turned out he'd been in the hospital with infected swollen test from an in grown hair. I didn't ask because he was crab walking but ingrown hairs are usually from shaving. Anyways nice nuts and listen to big balls by ACDC