Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

RE: Welding Over Galvanizing

[Subject Prev][Subject Next][Thread Prev][Thread Next]

Re: "The Procedure Handbook of Arc Welding", Lincoln Electric.

Welds on galvanized steel have more of a problem with porosity but are
usually within acceptance limits.  Fillet welds on galvanized steel have a
tendency to develop small cracks.  Weld metal cracks in galvanized steel are
intercrystalline with a zinc-rich layer lining the surface of the crack.  

The trick is to volatilize the zinc by oscillating the arc with a whipping
motion 1/8" to 5/16" ahead of the weld metal deposit, and using as large an
electrode compatible with the plate thickness and the electrode position.

Harold O. Sprague

> -----Original Message-----
> From:	Tom.Hunt(--nospam--at) [SMTP:Tom.Hunt(--nospam--at)]
> Sent:	Monday, October 01, 2001 1:21 PM
> To:	seaint(--nospam--at)
> Subject:	Welding Over Galvanizing
> Normally when welding galvanized steel we remove the zinc coating by
> grinding or other suitable means two inches either side of the weld.  I
> have heard that leaving the galvanizing is not good but not necessarily
> detrimental as long as all the other procedures and QA are followed.
> Obviously there is a venting concern for the gasses produced.
> Does anyone know the extent of the problems and detrimental effects the
> zinc may have on the weld?  I have a case where I need to fix a field
> problem and removing the galvanizing may be difficult.  This would be a
> 1/2
> inch fillet weld on new A36 3 inch diameter galvanized rods (+/- 4
> months).
> Thanks,
> Thomas Hunt, S.E.
> Duke/Fluor Daniel

******* ****** ******* ******** ******* ******* ******* ***
*   Read list FAQ at:
*   This email was sent to you via Structural Engineers 
*   Association of Southern California (SEAOSC) server. To 
*   subscribe (no fee) or UnSubscribe, please go to:
*   Questions to seaint-ad(--nospam--at) Remember, any email you 
*   send to the list is public domain and may be re-posted 
*   without your permission. Make sure you visit our web 
*   site at: 
******* ****** ****** ****** ******* ****** ****** ********