Structural Nut Color: Why Color Doesn’t Equal Coating

03/6/2018

Picture it: you receive your order of hot-dip galvanized structural nuts, open the container, and see that the nuts are blue. There must be a mistake. Aren’t hot-dipped nuts supposed to be green? That’s not always the case. Let’s go over dyes and why the color of the structural nut may not be what you were expecting.

Why are Structural Nuts Dyed?

While there’s no requirement that the lubricant should be dyed, many manufacturers put colored dye into the lubricant to easily distinguish the structural nuts. Because there is no set standard, different manufacturers use different colors for each kind of structural nut. Though you may be used to hot-dip galvanized nuts being green and mechanical galvanized nuts being blue, this can be the opposite for different companies. Some companies will use an entirely different color at their discretion. The colors are not present for the purpose of the customer, but for the manufacturer’s organization. 

Do I Have the Correct Structural Nuts?

Nine times out of ten, yes, you received the correct structural nuts. The best way to tell the difference in a hot-dip galvanized and a mechanical galvanized nut is by feel. Hot-dip galvanized structural nuts will feel grittier, while mechanical galvanized nuts will feel smoother.  That said, if you are still unable to tell the difference, our sales representatives are more than happy to assist you in ensuring you received the correct order.

Bottom Line

The colored dye in the lubricant on the structural nut serves two purposes: it shows that the nut is covered in the lubricant, and it helps the manufacturer keep each type of nut separate and organized. Different manufacturers use different colors to signify types of coatings, so it can get confusing if you are used to one color, and you receive another. You can usually confirm you received the right nuts by feeling the coating.

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