Q: I’m working in a reverse osmosis facility that purifies seawater for drinking water. We are experiencing some corrosion in some of our valve attachments which I’m assuming is from the salt water. Any recommendations on a fastener that won’t corrode in these conditions?
A: Your best bet would be a titanium bolt. Titanium is almost completely resistant to chloride corrosion and can even withstand stagnant sea water. If high strength isn’t a concern that you could go with Grade 2 bolts, which are relatively inexpensive. For strength above, 70 ksi tensile, then I’d suggest grade 5 titanium bolts which offer much higher strength, up to 148 ksi UTS.