Raised Welds After Galvanizing

Our customers take a lot of time and pride in their work, and want the completed product to

look its best.  We understand this desire, and always strive to make our customers happy.  

Quality and appearance are just as important to us as they are to our customers.  Below is

a short discussion that can aid our customers in reaching their goal, especially with products

such as handrail.

Raised welds after galvanizing are a common occurrence in the galvanizing industry, 

especially with handrail.  Many fabricators spend great amounts of time ensuring that the 

handrails and welded areas on the handrails are as smooth as possible.  These same fabricators

are then surprised when the handrails return from galvanizing and all of the welds they spent

so much time smoothing out, are anything but smooth.  Most likely, this has to do with a 

differing chemistry between the steel and the weld material -- namely the silicon level.  

Some concentrations of silicon can speed up the metallurgic reaction between the zinc and 

steel, causing rapid and large crystal growth.  This, in turn, causes the welds to become 

raised in comparison with the surrounding steel.  Fabricators need to pay close attention to

the silicon level of the weld material, to ensure that it is compatible with the steel in the parts

they are constructing.  Below is an article from the AGA discussing this issue in more detail: