making holes with stick electrodes 3

[Mohamed Elshamy]

in field if i need to make a hole in steel structure with stick electrode as exception because of the assigned hole to be extruded was shifted from it's place.
* is this ok?
and if not and i'm in site and the equipment is too limited what is your recommendations?
thank you so much

 

[racookpe1978]

You want our "permission" to blow an unspecified hole in an unknown steel part carrying unknown loads with a SMAW electrode because a hole is in the wrong place?

 

[DSB123]

Which group of Cowboys do you work for?

 

[gtaw]

Cutting bolt holes with an oxy-acetylene torch is bad, using a SMAW electrode is much worse. Bad move in the best of circumstances.

Best regards - Al

 

[Mohamed Elshamy]

First of all thank you all for your response
Mr. DSB123 better words would be fine and thank you any way
The matter we aren't making this work basically it is a matter of need and we already did it in a flange side in w shape with steel 37 and i just ask if it is prohibited why? Form scientific point of view
Thanks alot

 

[SectionIX]

Where to begin...

I can only hope that failure of this part does not lead to injury (or worse) because persons responsible have put themselves in an untenable position...

 

[DSB123]

SectionIX,
Hence my original comment - feel there could be some litigation down the line with these practices being employed.

 

[gtaw]

It is not a good practice because all bolts, when fully loaded will slip into bearing. since the hole burned through the structural member is not round, the bolt shank will be making point contact rather than bearing against a round surface.

The problem is compounded when the connection involves several holes and several bolts. As the connection is fully loaded, the connection will slip so each bolt will bear against the side of the hole. However, due to the inaccuracy of the bolt hole locations, an individual bolt will make contact with the side of the hole. Only the bolt in direct bearing against the side of the hole will (effectively) transfer the load into the adjacent member. While several bolts sharing the load will work, an individual bolt will be inadequate and will be overloaded. Ultimately the bolt in bearing fails and the load is transferred to the next bolt that slips into bearing, it fails and the process repeats until the connection fails.

This is the simplified explanation.

Best regards - Al

 

[DSB123]

gtaw,
A bolt in a bolt hole only makes a line contact in any case since the bolt hole radius is larger than the bolt radius until the bolt hole material yields and the bolt bearing area increases.

 

[gtaw]

The idea behind a bearing connection is that once in bearing and once the initial yielding takes place, all the bolts are in bearing and sharing the load. A single bolt in a bearing connection is not intended to transmit the entire hole. There are special provisions for oversized holes, i.e, they aren't used with bearing connections. Short slotted holes have to have their major axis perpendicular to the primary shear.

A slip critical connection has different provisions. Considering the circumstances of this case, I doubt we are close to meeting the requirements of a slip critical connection.

It is doubtful a series of holes located and melted through the members involved in the connection are such that the all bolts would be in bearing at any time unless it is in succession as one bolt after another fails.

My recommendation would be to locate the member and weld the connection and ignore the bolts.

Best regards - Al

 

[Mohamed Elshamy]

Gtaw
Thank you so much for your explanation as you whre very helpful and scientific as this is what I need just to understand, and thank you all for your helpful explanations .
Best regards

 

[DekDee]

Mohamed,
Certain codes allow "slotting" or elongation of holes but it is generally only allowed on certain types of connections and definitely not by gouging molten metal with the end of an electrode.
There is no excuse for " i'm in site and the equipment is too limited what is your recommendations"
I have had oxygen/acetylene bottles flown into a Papua New Guinea jungle hanging off a helicopter so I could slot some bolt holes !!!
Regards,
Shane