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Galvanized anchor bolts

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Eabrar

Mechanical
Jul 31, 2003
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Hello

We are converting the CO2 Removal Section at our Ammonia Plant from conventional Benfield system to Benfield LoHeat System. Anchor bolts of material ASTM A307 will be installed on heavy steel structure, carrying a load of 350 tons.

The supplier has offered hot dip galvanized anchor bolts; previously we have always used bare anchor bolts (w/o any coating).

Is it all right to use hot dip zinc plated anchor bolts in concrete foundations or there are some areas of concern that need to be evaluated/ controlled during fabrication of anchor bolts?
 
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No area of concern. Sometimes for small size bolts (<3/4") you need to account for the zinc on the bolt when you size the nut by making the nut slightly larger.
 
Someone else might correct me, but I thought embrittlement was only an issue with high strength bolts such as A325 and A490. And I think even those can be galvanized.
 
embrittlement is a concern when galvanizing A490 bolts. A490 is meant to be used in a bare or painted condition.
A325, A307, F1554 etc can all be HDG no problem. If setting in concrete you are much better off with galvnanized bolts rahter than bare anyway.
 
You can nt hot dip standard anchor bolts. Galvinized bolts are cut tob be galvinzed. If you dip regular bolts, the bolts & nuts will not fit and the galv will get stripped which can actually accelerate corrosion. Order galvinized (hot dipped) bolts.
 
Eabrar,
Using galvanized bolts inside concrete is not an issue. When you say hot dipped galvanized; what is the coating thickness in microns? You'll have to pay attention on this. Because, when you use galvanized anchor bolts in a aggresive environment, there is a rate of removal of the coating. If your coating is not enough, you'll be ended up with a difficult situation. Ask for "Sheradised" which has a coating thickness of approx. 43 microns or specify the galvanized thickness.
 
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