Hot dip galvanizing

Date 12-11-2008 13:58 Edited 12-11-2008 14:02

http://www.galvanizeit.org/aga/about-hot-dip-galvanizing/what-is-hot-dip-galvanizing/facts-about-hdg

Look around on this site (galvanieit.org - link above) and maybe search their archives if this doesn't fully answer your question.

http://www.galvanizeit.org/aga/about-hot-dip-galvanizing/what-is-hot-dip-galvanizing/faq#15

By hogan

Date 12-11-2008 17:15

In addition to what jwright650 has offered, sometimes Si content of base metal is a concern.

By jwright650 (*****)

Date 12-11-2008 18:14 Edited 12-11-2008 18:17

I have noticed that the welds if welded with a higher Si content filler will seem to "swell" or have an appearance of "swelling" after hotdipping in the galv bath....take notice of welds that were ground completely flat before galvanizing and then observe how that welded joint appears to not have been ground smooth afterwards.

Here is what Hogan was speaking about......http://www.galvanizeit.org/aga/about-hot-dip-galvanizing/what-is-hot-dip-galvanizing/the-hdg-coating#coating-thickness

By hogan

Date 12-11-2008 18:35

I have always wondered why there is a restricted Si range, for some jurisdictions, for base metal but none regarding deposited weld metal.

By Kix

Date 12-11-2008 18:46

I think that's a mixed gas fluxcore wire you're using, not for straight Co2. You can get 71 series wire designed for straight Co2 if you want.

By jwright650 (*****)

Date 12-11-2008 19:25

We use 1/16" dia Ultracore 71 with 100% Co2

By Kix

Date 12-12-2008 13:20

Does your wire have an M designation in it like his does? The wires with the M designation are designed to perform with mixed gas so I figured I just throw that out there for trouble shooting. I'm never against not going with the grain when something is proven to work, so If Co2 works with a wire designed to be used with mixed gas, then burn baby burn. ;-)

By jwright650 (*****)

Date 12-12-2008 13:27

The ultra Core 71 is a E71T-1H8...no "M"

By CHGuilford (****)

Date 12-12-2008 13:40 Edited 12-12-2008 14:00

Lincoln Outershield 71M works just fine with 100% CO2. We had used it for 15 years with CO2 and some occasional use in the satellite locations using 75/25. I have run 15 to 20 PQR tests with it using CO2 (every 3 years - AWS D1.5).

You can see CO2 is listed on the data sheet for 71M - as well as argon/CO2 mixes. The last Lincoln annual C of C that I have for 71M was run by them with 100% CO2.
http://www.mylincolnelectric.com/Catalog/consumabledatasheet.aspx?p=5743

Edit : added 2nd link
http://www.mylincolnelectric.com/LEExtranet/certs/pdf_lib/US14160_20080717.pdf

John's direction to galvanizeit.org will lead to a lot of information on the topic. One thing to note is that is is not only the silicon content that affects the zinc layer - there are other elements responsible as well. In fact different heats of steel can lead to differences in appearance due to variations between the heats.

By Kix

Date 12-12-2008 14:45

Are you using the Outershield 71M E71T-1C (Straight Co2) or the Outershield 71M E71T-1M (mixed gas). The 1M is what I was reffering to and thought he might be using that because it will runs pretty darn good in my opinion compared to running the straight Co2 with the 1C. If you run the 1C with mixed gas it will run like hell, but never tried straight Co2 with the 1M.

By CHGuilford (****)

Date 12-13-2008 15:42

I think you'll find that the Lincoln Outershield 71M is a singular product that conforms to several specifications.

By Kix

Date 12-15-2008 13:21

I agree, It conforms to several specifications, but 71M has a few different classifications.

By TimGary (****)

Date 12-13-2008 01:56

There are a lot of good posts about this on this forum.
Search for Liquid Metal Embrittlement.

Tim