Misaligned bolt holes repair 2

[rowe]

A36 structural steel beam w/ 4 bolt holes (13/16" dia.) at end were misaligned by the fabricator. The holes were drilled approx. 1" offset from the req'd position. Field repair consisted of filling holes w/ e70 weld and redrilling holes in the correct position. Is this repair adequate? Thanks for the help.

rowe

 

[metengr]

Yes, as long as a qualified weld procedure specification was used with qualified welder(s).

 

[hogan666]

rowe,
AWS D1.1 (06) C 5.26.5 has a very good technique for this. I have used this on a few occasions when welds were required to be RT'd. We never had a reject.

 

[rowe]

met and hogan,

thanks for your help,

rowe

 

[wedling]

hogan666,
Would you recommend any practice for filling a 40 mm thick hole with a counterbore 40mm dia around 35 mm thick by welding.
it should be mentioned that there are two holes in each plate and the main thing is that there will be an overlap between the old and new hole.
The plate is underneath of bridge bearings.
Thanks

 

[Ron]

wedling...this would be a fracture critical application and would require a qualified welding procedure for the plug weld to be used. Considering the thickness, you might also need to control preheat and postheat temperatures and hold times. See AWS D1.1 bridge section.

 

[wedling]

Ron,
which clause of AWS D1.1 are you talking about.
If that is 5.26.5 I couldn't clear whether its possible or not.
beside that, in case we dont consider it as a fracture prone part, what would be suitable procedure to fill a 40 mm dia hole .(preparation,angles,sequenceses,...)
Thanks,

 

[HgTX]

If it's under the bridge bearings, it's probably compression & not fracture-critical. D1.5 only covers the bridge *above* the bearings, and any FC provisions are in D1.5, not D1.1. (Also D1.1 deleted its bridge section after they created the D1.5 bridge code in 1988.)

D1.1 clause C-5.26.5 (that's commentary) tells you what you need to know about restoration of holes by welding. I don't understand what you mean by "couldn't clear whether it's possible or not". You do it with stringer passes, not by inserting a rod in the hole and swirling it around.

Hg

Eng-Tips policies: faq731-376

 

[hogan666]

wedling,
The welding of mis-located holes, as described in C-5.26.5, looks to be appropriate for your situation. As HgTX has mentioned, this is part of the commentary and a mandatory part of AWS D1.1. Although it is helpful. It is common for fabricators to fill mis-located hole by the method mentioned by HgTX, to "insert rod and swirl it around". To weld in a spiral from the outside of the hole to center layer after layer until filled. This will present difficulties if the weld is required to have any type of volumetric NDT (RT or UT). If I were in your situation I would utilize the advise in the commentary. Use a similar material cut to the Dia. of the hole as backing. Shape the hole into a canoe shape on the other side, to allow for the deposition of stringers. Weld it out, and grind flush. Next back-gouge the Backing material to clean weld metal ( I would also suggest a MT examination at this point, if final weld requires NDT ), shape the gouged area to a canoe shape as was done on the other side. Weld it out, grind flush. Perform volumetric NDT if needed. Now drill hole in correct location.