Snug tight condition
Snug tight condition
(OP)
Hi,
My subcontractor ios asking me to provide him with the Torque value for bolts, but the specification of the project is telling that the bolts shall be SNUG TGHTINED,AISC360 is defining the snug tight condition as the tightness required to bring the connected plies into firm contact.
I have a serious concern to do the tightening without required torque value, what do you think?
My subcontractor ios asking me to provide him with the Torque value for bolts, but the specification of the project is telling that the bolts shall be SNUG TGHTINED,AISC360 is defining the snug tight condition as the tightness required to bring the connected plies into firm contact.
I have a serious concern to do the tightening without required torque value, what do you think?






RE: Snug tight condition
RE: Snug tight condition
Basically, if the nut is on tight enough that you can't remove it by hand then it is sufficiently tight for the snug-tight condition assuming the plies are in firm contact.
To establish torque values for final pre-tensioning requires a preinstallation test as documented in RCSC Section 7.
Al Harrold
RCSC Chairman
RE: Snug tight condition
RE: Snug tight condition
Mike McCann, PE, SE (WA)
RE: Snug tight condition
RE: Snug tight condition
I had a job where the inspector ran around with a little go/no gage thickness gage. I don't think it had any value other than he made a big deal about it and all the erectors made sure to snug the bolts just to get rid of the guy. So in that respect, it proved to be a very functional gage.
RE: Snug tight condition
Mike McCann, PE, SE (WA)
RE: Snug tight condition
Torque is effected by to many variables. Surface friction, bolt lubrication, tool calibration, etc. Therefore torque provides an inconsistent result. For bearing bolt connections the primary objective is to bring all plies into firm contact, any residual bolt pretension is irrelevant to the bolt shear capacity.
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