Thread lenght requirements ( after torque)
Thread lenght requirements ( after torque)
(OP)
I am needing help on codes that address, Threads showing
through nut after torque,on ASTM A325 and A490 bolts.
I have always used 2t-3t, after torgue as rule of thumb.
Any clarification would be appreciated
through nut after torque,on ASTM A325 and A490 bolts.
I have always used 2t-3t, after torgue as rule of thumb.
Any clarification would be appreciated





RE: Thread lenght requirements ( after torque)
I have found the project specifications determine this dimension. Or, it may be a proponent specification. Typically "full thread engagement" (FTE) is all that is required UNO.
When I worked for ARAMCO, their specification was 3 threads. Anything less had to be evaluated by the inspector and approved by the Project Engineer. Please note this applied to all connections whether a pressurized system or structural application. Another client of mine had the same 3 thread requirement, but it was for a dynamic/cyclic application (amusement devices).
I have in my collection of noncompliant materials a 1-1/2" dia. nut that was cut in half (I only needed one) for an A 325 galvanized fastener. The contractor claimed they had FTE. I rejected all of these connections as quickly as I could write. They should have reversed the installation of the bolt and there would not have been any problems. Replacing these with nuts that were not modified and reversing the installation cost them plenty in manhours.
RE: Thread lenght requirements ( after torque)
AISC Specifications for Structrual Joints using ASTM A325 or A490 bolts Par 2(b) "The length of bolts shall be such that the end of the bolt will be flush with or outside the face of the nut when properly installed"
This specification usually applies if you are dealing with Structural Building Issues ie: Specifications call out for building in accordance with ICBO/ICC - which refers to AISC for bolting and other issues. This information is from the Manual of Steel Construction ASD Ninth Edition Section 5.
You can also download the most recent version from AISC.org website.
RMP
RE: Thread lenght requirements ( after torque)
As for 'Torqueing' the same manual does not recognize torque values. If you have to do the arbitration inspection, someone fell down on the job... Just MESHO... [:)]
RE: Thread lenght requirements ( after torque)
Thread725-57019
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
RE: Thread lenght requirements ( after torque)
RE: Thread lenght requirements ( after torque)
By the time I retired in '98 I am told that most bolted connections were using TS bolts. That would seem to solve this particular problem.
Rod
RE: Thread lenght requirements ( after torque)