HIGH-NICKEL ALLOY TANK FABRICATION

Like most shops in our industry, Watson builds the majority of its tanks in 304 and 316 stainless, and material selection is driven by what the customer’s process needs. Some processes are too aggressive for standard stainless: hot chlorides, strong acids, high-temperature caustics, etc. For those, the answer is a duplex or high-nickel alloy, yet many tank shops won’t quote it. Watson doesn’t shy away from it.

We fabricate vessels and components in duplex stainless steels such as 2205 and super-austenitic grades such as AL-6XN. We also work in Hastelloy C-276 and C-22 (also sold as Alloy C-276 and Alloy C-22), Inconel grades such as Alloy 600 and Alloy 625, and other high-nickel alloys specified for demanding corrosive environments. Don’t worry if your spec calls out the grade by its generic name or the mill’s brand name. We work from either.

The alloy is only as good as the fabrication. Duplex and high-nickel alloys are less forgiving than standard stainless, and poor heat control or contamination during welding can undo the corrosion resistance you’re paying for. That’s why we control every step. Our welders are qualified on each of these alloys, and as an ASME code shop, we maintain lot traceability of material through every step of the fabrication process, tracking heat lots and verifying with positive material identification (PMI), so you know exactly what’s going into your tank.

Finishing matters as much as welding. On request, we provide tailored passivation treatment, which helps the passive layer that makes these alloys resist corrosion form properly. Electropolishing is also available where the process calls for it.