ASTM A325 Bolts - Chrome Plated or similar finish
ASTM A325 Bolts - Chrome Plated or similar finish
(OP)
I just come from a job site where ASTM A325 have been used, not tension controlled type, and they are chrome plated or some kind of shiny finish, and marked H H H - ASTM A325. I am going to ask for the paperwork, but I though I'd ask here if this is OK.






RE: ASTM A325 Bolts - Chrome Plated or similar finish
RE: ASTM A325 Bolts - Chrome Plated or similar finish
They look more the finish for bolts you can get at a hardware store, but those are Grade 2, 5 or 8.
These bolts are marked A325, so that's my concern.
RE: ASTM A325 Bolts - Chrome Plated or similar finish
RE: ASTM A325 Bolts - Chrome Plated or similar finish
RE: ASTM A325 Bolts - Chrome Plated or similar finish
RE: ASTM A325 Bolts - Chrome Plated or similar finish
RE: ASTM A325 Bolts - Chrome Plated or similar finish
RE: ASTM A325 Bolts - Chrome Plated or similar finish
4.3.1 When zinc-coated fasteners are required, the purchaser
shall specify the zinc coating process, for example, hot
dip, mechanically deposited, or no preference.
4.3.2 When hot-dip is specified, the fasteners shall be
zinc-coated by the hot-dip process and the coating shall
conform to the coating weight/thickness and performance
requirements of Class C of Specification A 153.
4.3.3 When mechanically deposited is specified, the fasteners
shall be zinc-coated by the mechanical deposition process
and the coating shall conform to the coating weight/thickness
and performance requirements of Class 50 of Specification
B 695.
4.3.4 When no preference is specified, the supplier shall
furnish either a hot-dip zinc coating in accordance with
Specification A 153, Class C, or a mechanically deposited zinc
coating in accordance with Specification B 695, Class 50.
Threaded components (bolts and nuts) shall be coated by the
same zinc-coating process and the supplier’s option is limited
to one process per item with no mixed processes in a lot.
4.4 Lubrication—When zinc-coated nuts are ordered with
the bolts, the nuts shall be lubricated in accordance with
Specification A 563, Supplementary Requirement S1, to minimize
galling.
RE: ASTM A325 Bolts - Chrome Plated or similar finish
RE: ASTM A325 Bolts - Chrome Plated or similar finish
RE: ASTM A325 Bolts - Chrome Plated or similar finish
www.FerrellEngineering.com
Providing fabrication and erection efficient structural design of connections. Consulting services for structural welding and bolting.
RE: ASTM A325 Bolts - Chrome Plated or similar finish
This might be coming a little late in the conversation but here's one definite possibility:
a) galvanization recipes vary from one shop to another, but also from one client type to another.
b) when the galvanization recipe includes more ALUMINUM is provides a very nice finish, close to what a chrome plating would be. This hot-dipped galvanizing recipe is reserved for consumer products, where aesthetics are more important than durability, and where the product life cycle is expected to be shorter. For industrial projects where life cycle projects are expected to have a longer life they will put minimal aluminum and more zinc. The finish is a dull grey but has a significantly longer life. Note that this is because aluminum oxidizes more readily than zinc.
Occasionally there is a mix up in hot dipped galvanization and customer don't get what's expected, especially if they didn't specify anything.
RE: ASTM A325 Bolts - Chrome Plated or similar finish
RE: ASTM A325 Bolts - Chrome Plated or similar finish
www.FerrellEngineering.com
Providing fabrication and erection efficient structural design of connections. Consulting services for structural welding and bolting.
RE: ASTM A325 Bolts - Chrome Plated or similar finish
RE: ASTM A325 Bolts - Chrome Plated or similar finish
Does the specification actually prohibit electroplating, or just doesn't mention it? They are probably just considered as plain black bolts, as the electroplating does little to achieve corrosion resistance.