Q:
I’m running a cotton mercerizing process that is being altered to utilize sulfuric acid. I didn’t realize how corrosive using sulfuric acid (H2So4) is on my fasteners. Any ideas on how to protect my bolts. Not super hot, just corrosive.
A:
Alloy 20 bolts are a good choice for this. It was specifically designed for use in hot sulfuric acid, easily handling boiling sulfuric acid in 20% to 40% concentration, as well as general sulfuric acid resistance. If Alloy 20 bolts do not do the trick then you can up your resistance to Hastelloy C276 bolts which are ideal for use in hot sulfuric acid at higher temperatures and concentrations than Alloy 20 fasteners.