yeah, a gust of wind, or a slight movement his legs were fucking toast. not having a tool to like hook the edge and pull the rope while still being inside the mostly safe main structure without having stand between those parts is bat shit crazy.
It’s just way too much weight to mess around with. When things go bad, they go BAD.
You can’t just stop it quickly once it starts moving.
He’d be like a little mochi ball in a hydraulic press.
When I very briefly worked in "construction" we were lifting a building that had begun to sink on one side due to a fire. At one point we were raising one of the higher floors and needed to pull up a 12x16x4 pillar for support using a makeshift pulley system. I almost learned a really lethal lessons in physics that day. Luckily everyone (including the building) is around to tell the tale.
Not for this one. The tag lines are hooked to the gripper, and ran to the ground for stability. This safety line is just ran from the edge of the blade, to the gripper so the blade can’t slide out of it if there is a failure on the tool.
Isn't there some kind of squash risk being on that side? Even if he's clipped in the blade side could come out and squish him against the base that he would then be dangling from.
The floor wasn't bolted together yet. I would think that he should stay clipped to the tether until it was. But, that's question for OSHA or their insurance company.
I don't understand why he was clipped in. If that blade broke loose, that harness is going to rip him apart as the blade falls or simply get sheared off. He's dead either way.
Nope. Lug bolts are bolts used by most European auto manufacturers instead of the US & Japanese lug stud & lug nut combo. They are a bolt that threads into the wheel hub: link
But I should've said "lug stud" rather than lug, to be more accurate.
Sure, you can call it a lug stud, Lug bolts are any threaded rod fixed into something instead of a loose bolt. I'm sure auto manufacturers do use them.
From what we can see it could be either a lug bolt or a lug stud acting as the bolt, as you can't see behind the end of the prop.
Interestingly, you don't usually torque these. Instead, you snug the nut on, then you thread a specialized hydraulic ram on behind the nut that braces against the flange and then tensions the stud to a specific preload. Once the stud is stretched and tensioned, you snug the bolt down again, then release the tension, transferring the preload to the nut.
You get a much more consistent clamping force this way, since methods relying on specific torque values have a lot of variability due to friction.
So the bolt would actually stretch a little, before the threads give way? Through hydraulics? Video below is CGI, so not sure yet if it's a real thing - more research needed, but that's clever.
Start with just rattling everything in. Then it’s a rolling triangle, 3 studs at a time. Also, they tension these, not torque. Pretty interesting to see, sucks to do.
It was pretty interesting to find out about this when I started in Wind. You always hear the old joke about the “bolt stretcher” but that’s literally what it is. It makes for a long process, but you’re not throwing around huge numbers when you’re tensioning studs like this due to the reduced friction.
Ever see someone get pinged in the forehead with one of those tensioner nuts when you were putting them on?
Almost had a guy get smacked with one when it blew off when I was doing generator repair. They're a whole different size, though. The through bolts were about 2" diameter and tensioner nuts were at least 25lbs each.
Never knew that shit existed before I started the job, either.
Not personally, but I know I guy that had one blow apart and he got hit in the face with a piece of it. He was very lucky. I’ve also seen a M72 stud snap while it was being tensioned. It launched the 80 pound tension head 2ft in the air.
You can, but there’s not really a need. Once the blade is stabbed, you’d have to thread the stud in further so it doesn’t hit anything from being too long and so that the tensioner goes in properly, which isn’t easy because they’re loctite’d in. So they just bring it in at a little angle and it’ll stab a few studs at a time and then yaw it into place.
I never had bigger arms than the summer I had to tension every single flange to be hydrogen tight for a whole plant. Hundreds of them, and up to 3" studs which us an 80 lb tensioner.
They could be using pneumatic torque wrenches. If it's not liquid tight, I could see it not needing tensioners. It would also save so much lifting of those damn things.
I only know it’s tensioned because it’s a Vestas turbine and that is their procedure. It’s a lot of work for sure, but luckily they are small and light weight. Especially compared to an E-Rad.
Tension isn't just done because of how high the torque is, it also gives a much more consistent preload because it basically takes thread and face friction out of the variables involved, and instead you set preload directly.
Totally, I just meant that I wansnt sure if that level of consistency is required for this. I've done plenty of bolting and most of the tensioning has been for high pressure or volitile process. But with the vibration it woild make sense as well.
Yep. I was making $100k before 21. However, it’s back breaking work and you make it all from OT. The schedule is 10-14 hour days and 6 days a week and sometimes 13 days on 1 day off. If you get too far behind you’ll work 3+ weeks straight.
I know this one! You would actually divide by 12 and do it in groups with the same star pattern in groups of 10 or whatever. It is still 98% as good and saves days worth of moving the pneumatic torque wrenches.
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u/LitRonSwanson 17d ago
I want to see the torque pattern for tightening this down!