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RE: Twist off bolts (was: Bolt retightening)

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I would second Harold's endorsement for any seminar Mr. Shaw is giving. I
caught one on welding once in the Seattle area and it was one of the most
practical and worthwhile steel seminars I ever attended. 

-----Original Message-----
From: Harold Sprague [mailto:spraguehope(--nospam--at)hotmail.com] 
Sent: Wednesday, September 28, 2005 3:29 PM
To: seaint(--nospam--at)seaint.org
Subject: RE: Twist off bolts (was: Bolt retightening)

It is worth the time and money.

Uncompensated endorsement complete.

Regards,
Harold Sprague





>From: "Robert E Shaw Jr" <rshaw(--nospam--at)steelstructures.com>
>Reply-To: <seaint(--nospam--at)seaint.org>
>To: <seaint(--nospam--at)seaint.org>
>Subject: RE: Twist off bolts (was: Bolt retightening)
>Date: Wed, 28 Sep 2005 18:19:48 -0400
>
>Thanks, Harold for the plug on the seminars. For those who are now 
>interested, my seminars are in Buena Park next week (one on Steel
>Connections: Seismic Applications and one on Structural Welding: Design 
>and
>Specification) and the following week, the two day-seminar on 
>Structural Steel Inspection. I then repeat these three seminars in 
>South San Francisco the last two weeks of October. Seattle gets SCSA 
>and SSI right after Thanksgiving, and Vegas is in December (Structural
Steel Inspection only).
>
>I spend about 3-1/2 hours on bolting in the Structural Steel Inspection 
>seminar. Always a fascinating discussion about what really happens and 
>some of the lunacy that takes place from the engineering, construction 
>and inspection disciplines.
>
>Seminar info at www.steelstructures.com
>
>Shameless plug complete.
>
>Bob Shaw
>SSTC
>
>-----Original Message-----
>From: Harold Sprague [mailto:spraguehope(--nospam--at)hotmail.com]
>Sent: Wednesday, September 28, 2005 6:04 PM
>To: seaint(--nospam--at)seaint.org
>Subject: RE: Twist off bolts (was:Bolt retightening)
>
>Tom,
>That is correct.  That is why the twist off manufacturers are 
>conservative in the torque it takes to twist off the bolt.  Another 
>critical factor is the lubricant.  If you have a large complicated 
>structure and the steel is erected and plumbed.  Then you take a couple 
>of weeks off because of the rainstorms that blew through.  You need to 
>pull a pretty good sampling of bolts, load them into the Skidmore and 
>verify if you are getting the tension.  If not, you need to pull the 
>bolts and relubricate them.  If the bolts have surface rust, you can be off
on the tension by a factor of 2.
>
>That is why special inspection by a QUALIFIED inspector is important.  
>You can make it fool proof and require the DTI washers plus the DTI bolts.
>That
>
>way you can see on each and every bolt if you have the proper tension.  
>When
>
>the washer squirts, you have the tension.  And you have the ease of 
>installation offered by the twist off bolts which use electric wrenches 
>and are light and easy to operate.
>
>I think it would be fun to take some engineers out on a site, and have 
>them install bolts using the various techniques.  It is also 
>entertaining to remove the lubricant from a few bolts and even have 
>some with light surface rust.  Then put them into the Skidmore and see 
>how much tension you are getting.  Or you can keep your clothes clean 
>and attend one of Bob Shaw's highly educational presentations on bolt
installation.
>
>I have done both.  I am a slow learner due to too much suds sucking as 
>an iron worker back in my bullet proof days of youth.
>
>Regards,
>Harold Sprague
>
>
>
>
>
> >From: "Tom Skaggs" <tom.skaggs(--nospam--at)apawood.org>
> >Reply-To: <seaint(--nospam--at)seaint.org>
> >To: <seaint(--nospam--at)seaint.org>
> >Subject: Twist off bolts (was:Bolt retightening)
> >Date: Wed, 28 Sep 2005 14:06:16 -0700
> >
> >The problems with relating bolt tension with torque (i.e. calibrated 
> >torque wrench) were well documented in this thread.  I also 
> >understand DTIs are a direct measurement of bolt tension, but aren't 
> >the twist off bolts just another torque based method and not measuring
direct tension.
> >I've briefly looked at the NUCOR website, perhaps I don't understand 
> >the twist-off mechanism.  Please explain?
> >
> >Tom
> >
> >________________________________
> >
> >From: Michael Hemstad [mailto:mhemstad(--nospam--at)mbjeng.com]
> >Sent: Wednesday, September 28, 2005 13:36
> >To: seaint(--nospam--at)seaint.org
> >Subject: Bolt retightening
> >
> >
> >Kevin,
> >
> >I concur with Harold (I'm sure he's relieved to hear that).  One of 
> >the huge and seldom-quoted advantages of twist-off bolts is that they 
> >can be inspected with certainty, from the ground, with very little 
> >effort on your part.  If the spline is twisted off, it's done.  
> >Therefore it is entirely feasible to inspect every bolt on a project.  
> >It really adds to everybody's peace of mind.  And, as Harold notes, 
> >it's also probably the cheapest solution.
> >
> >I've never had to spec these bolts into a project, because they're 
> >universally used around here; but if I saw ironworkers using the 
> >old-style bolts and spud wrenches, I'd start asking a lot of questions.
> >
> >Mike Hemstad, P.E.
> >
> >Meyer Borgman Johnson
> >
> >Minneapolis, MN
> >
> >---------------------------------------------------------------------
> >---
> >--
> >
> >From: "Harold Sprague" <spraguehope(--nospam--at)hotmail.com>
> >
> >To: seaint(--nospam--at)seaint.org
> >
> >Subject: RE: Bolt retightening
> >
> >Kevin,
> >
> >Torque wrenches are only supposed to be used in arbitration in the
> >
> >installation of A325 or A490 bolts according to the RCSC. Torque is a 
> >very
> >
> >poor indicator of tension in a bolt. The tension is what you are 
> >trying to
> >
> >achieve.
> >
> >Getting a Skidmore on the project site (hydraulic tension indicating
> >device)
> >
> >is not a big deal for most iron workers, and is fairly routine.
> >
> >Because of the variability, I would NEVER allow calibrated wrench 
> >bolt
> >
> >tightening.
> >
> >When you boil it all down, the best and probably cheapest solution is 
> >to
> >
> >replace all of the bolts with the tension indicating bolts using the
> >
> >splines. The installation wrench rotates the nut while holding the bolt.
> >
> >The spline snaps off when the appropriate tension is achieved. You 
> >still
> >
> >have to install the bolts to "snug tight" with the faying surfaces in 
> >full
> >
> >contact. And you still need the Skidmore on the site to verify the
> >
> >appropriate tension for the tightening procedure you select. The
> >
> >installation is a lot easier using the twist offs as opposed to using 
> >a
> >
> >pneumatic wrench or a spud wrench with a cheater (for turn of the nut).
> >The
> >
> >labor is where you will save the money over other installation methods.
> >And
> >
> >the QC is better.
> >
> >If you want the ultimate in reliability, ease of installation, and 
> >100% QC,
> >
> >use the DTI "Squirter" washers with "twist off" bolts. You get the 
> >ease of
> >
> >installation with the "twist off" wrench and you get the tension 
> >indication
> >
> >that the "squirter" washers provide.
> >
> >If you decide to go against my incredibly sage advice and use turn of 
> >the
> >
> >nut, use match marking with a paint stick. And never tighten bolts 
> >without
> >
> >a Skidmore.
> >
> >Regards,
> >
> >Harold Sprague
> >
> >
> >
> > >From: Kevin Below <kevinbelow(--nospam--at)videotron.ca>
> >
> > >Reply-To: <seaint(--nospam--at)seaint.org>
> >
> > >To: seaint(--nospam--at)seaint.org
> >
> > >Subject: Bolt retightening
> >
> > >Date: Mon, 26 Sep 2005 22:48:26 -0400
> >
> > >
> >
> > >I am in need of some guidance on the right technique for 
> > >retightening
> >
> > >bolts on a 40-year-old steel structure....
> >
> >
> >
>
>_________________________________________________________________
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