Q: I’ve been using Monel 400 bolts for a coastal operation that is built in polluted, stagnant saltwater. I’m been having some slight corrosion – nothing drastic, but wanted to check if there was another material that would last longer.

A: For this situation I would suggest titanium bolts. Titanium screws can handle both rapidly moving seawater as well as stagnant water. Monel 400 bolts can sometimes see corrosion in stagnant waters. Titanium bolts also offer excellent protection in polluted waters. My only concern would be that the waters are polluted with strong acids. In that case the Monel may be a better option because titanium screws cannot handle acidic corrosion as well as Monel screws. titanium screws for saltwater corroion

Q: We are installing bolts into a refinery wharf.  After doing a test run on a few A316 stainless steel bolts, they came back heavily corroded. Do you have an coating that can be used for salt water applications that would prevent this? Or do can you advise on another material?

A: I don’t recommend a coating but I can recommend a better material to handle the saltwater situation. Here I would suggest using either Monel or titanium bolts. Monel bolts are the go-to material for many marine applications. It is available in two forms Monel 400 which offers a strength of 83ksi ultimate tensile strength and age hardened Monel K500 for extreme strength of 160ksi UTS. Titanium bolts are also and excellent choice for saltwater corrosion. They offer excellent resistance to both rapid velocity and stagnant seawater, up to a mile deep. Titanium grade 5 fasteners are 4 times stronger than 316 at half the weight.