Power tool for bolt torquing
Power tool for bolt torquing
(OP)
I'm currently running tests on CPVC flanges. The assembly requires the flanges be assembled with a rubber gasket inbetween and 8x 5/8 nuts and bolts per set. The bolts are tightened in a cross pattern, torqued in steps of 20, 40, 80 and 110 ft-lbs. I have had 20 tests done so far using a torque wrench, but I'm finding that the torquing of the bolts is taking up too much time and energy. There are at least 50 more tests scheduled in the short-term and regular inspection tests in the long-term (some of the QC technicians are significantly weaker than me).
So far, I have tried a pneumatic impact gun I borrowed form the floor, but I could not set a specific torque (I had a 0-5 dial) and it has been damaging the nuts and bolts (for this size/grade, they're kind of expensive, so reusing would be nice). I have also been looking at pnuematic nut runners, but have not found one with a high enough torque to be of any use. I am wondering if anyone knows of any power tools that can be used to torque bolts to 20, 40, 80 and 110 ft-lbs (or maybe +/- 5 ft-lbs) without destroying the nuts and bolts after each use? Thanks!
So far, I have tried a pneumatic impact gun I borrowed form the floor, but I could not set a specific torque (I had a 0-5 dial) and it has been damaging the nuts and bolts (for this size/grade, they're kind of expensive, so reusing would be nice). I have also been looking at pnuematic nut runners, but have not found one with a high enough torque to be of any use. I am wondering if anyone knows of any power tools that can be used to torque bolts to 20, 40, 80 and 110 ft-lbs (or maybe +/- 5 ft-lbs) without destroying the nuts and bolts after each use? Thanks!





RE: Power tool for bolt torquing
I found a fair number of electronic torque wrenches for sale. I couldn't find an indication that they were, or were not, adaptable to doing torque steps without a lot of screwing around, but many of them can be had with computer links for verification.
It occurs that you could do torque steps with fixed clicker torque wrenches by inserting a series of torque multiplier adapters, one at a time, or by coming up with a torque multiplier bar that telescopes stepwise. I haven't seen such a thing for sale, so it would have to be homebrewed. It would have the virtue of offering increasing length and leverage at each torque step, so the tech wouldn't have to be unusually large.
Even something as simple as letting the techs work in teams of two or four might speed up the operation a bit.
Mike Halloran
Pembroke Pines, FL, USA
RE: Power tool for bolt torquing
RE: Power tool for bolt torquing
You will need solid torque arms too.. At those levels you will start breaking fingers/wrists,etc with a "powered" tool without them. For us anything over 75 in-lbs (yes in-lbs) with pneumatic tools gets a torque arm or the injury reports come flying in..
Like said above..prepare for sticker shock... Or really just forget it and continue with your manual torque wrench.. The ROI to invest in a powered solution will be VERY..VERY long.
I'd expect a min of $10k.. Heck just the small "production" electric screwdrivers (up to 16 in-lbs,etc..) are $600 to $1500 each..
RE: Power tool for bolt torquing
Some multipliers have a torque indicator dial.
RE: Power tool for bolt torquing
RE: Power tool for bolt torquing
Brett Linzer / www.CheckLine.com
RE: Power tool for bolt torquing
Jon