Unknown Galvinizing Defect's

[Af716]

I'm at a loss I don't know what this* the Galvinizer doesn't know what it is. We sent some poles made out of Astm A572 Gr. 65 to be dipped* this is what we got (see pic's) If anyone has any idea please let me know. Thanks

[etmx]

To my opinion:
1) Short glvanization time (there is no development of the zinc "baterfly" on the sufaces. It is just "silver" nature laywer (photo 4694). Also the pealling of this photo indicates short time of boiling in the bath (the zinc had not been adheared with the subtrate). From the coloring of the bare Carbon Steel surface can be assumed that they have not cleaned the metal before the zinc bath.
2) they were not removing the floating rust during the galvanization process (photo 4696)
3) the other two photos indicate that after the completion of the galvanizing process they had not tried to "dry" or "drain" the excess zinc traped inside the poles. They took them out as they were in the bath.

I hope that I helped you.

[Mikepehli]

All the above already mentioned plus more details as low Zinc bath temperature* the acid bath is already saturated* depleted* and did not replenish / make up / clean etc
The Galvanizers are NOT professionals who know how to do the job
Change the Galvanizers you are not going to get any good results from this galvanizing factory
Easy to say more difficult in practice

[Af716]

So does this explain the zinc crystal formations?

[Mikepehli]

in which country is the bath?
Provide more information as a drawing with dimensions for the column for each pc you HDG
The vent holes Dia and locations is one major factor
It looks like that there are multiple causes
Start asking for the Zinc quality spec and how do they check the Zn ingots are the correct ones
These crystals sound that they some form of another alloy and impurities.
Do you have access to Metallurgical lab and get the crystals to check under the microscope

[Af716]

I have attached some more pictures* close ups magnified up to 8x. the last attachment is the dimensional info
The poles where processed in the United States* We unfortunately don't have access to a lab

[link Point to another website Only the registered members can access] afierro716@gmail.com

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[Mikepehli]

Pics
You have all kinds of errors as can be seen from pics
Welding details as not completely suitable for HDG
Zinc bath temperature not correct sounds
Try and get bath temperature readings with another instrument* non contact type as from Fluke
Pyrometers permanent sound that they have a big error
Poles dirty / not properly sand blasted surfaces
Acid bath is saturated i.e. depleted
Most likely the Zinc ingots are not clean enough* they must have magnesium and other contaminants.
Can you get the Zinc ingots chemical and mechanical analysis?
Bath surface also is not cleaned from the floating zinc oxides
The method how is dipped the pole into the bath

[Af716]

I can ask* however I doubt they'll be willing to provide any info* the galvanizer has not being very cooperative with any of our request for information.
In one of the pic's there is large block's of dross* is there anyway that this can be dross? It's been suggested that these formations are a byproduct of dross accumulation.

[Mikepehli]

if you have pay him it is a lost issue.
See what the PO or contract is saying.

It is a 100 % Zinc bath problems

Talk to the Zinc bath top management

Which country is the zinc bath?i

If you need to install urgently

[Af716]

I can ask* however I doubt they'll be willing to provide any info* the galvanizer has not being very cooperative with any of our request for information.
In one of the pic's there is large block's of dross* is there anyway that this can be dross? It's been suggested that these formations are a byproduct of dross accumulation.

[Af716]

We have not paid him not took possession of the poles. The Galvinizer is in the State of Kansas* United States

[Af716]

I'd still like to know how the zinc crystals formed. One consultant I spoke with said it sounded like zinc whiskers* just on a much* much larger scale.