coated fasteners for corrosion resistance
coated fasteners for corrosion resistance
(OP)
I am attaching two carbon-steel parts (pump columns) together using flanged connections. The application is underwater in brackish environment (let's say 3600 us/cm). In the past when we've used carbon steel parts in this application, we see some surface corrosion at the location of the B8 fasteners (after several years). This is not necessarily unexpected considering differences in galvanic cell potential and application. See pic:

I am considering using coated B7 fasteners (e.g. fluorokote #1) in an attempt to minimize part corrosion and fastener corrosion. Co-workers have questioned this approach as replacing one minor problem with a worse problem. Any thoughts?
Also, I have no way to avoid using the SS lockwasher but I don't feel like it will cause much problem given its small surface area.

I am considering using coated B7 fasteners (e.g. fluorokote #1) in an attempt to minimize part corrosion and fastener corrosion. Co-workers have questioned this approach as replacing one minor problem with a worse problem. Any thoughts?
Also, I have no way to avoid using the SS lockwasher but I don't feel like it will cause much problem given its small surface area.





RE: coated fasteners for corrosion resistance
Other than that, one of the flourocarbon coatings will certainly do better than what you have there now.
RE: coated fasteners for corrosion resistance
RE: coated fasteners for corrosion resistance
Can you provide references that support eliminating helical lockwashers on rotating equipment (other than general google searches). We typically take credit for thread adhesives as an alternate method of threadlocking but I'm not sure it would be effective without metal contact.
RE: coated fasteners for corrosion resistance
You can search this site for lock washer and find numerous threads. Here is a good FAQ: FAQ404-1257: Is a lock washer an effective torque retention device?
RE: coated fasteners for corrosion resistance