DOT 3AA Nitrogen Storage Module – 122 Cu Ft | 2640 PSIG | 20,000 SCF/N2/AR/HE Ready to Go

Is this ASME or DOT rated, and what does that allow me to do with it?

This is DOT rated—specifically DOT 3AA-2400 with 10% overfill stamping, giving it a 2,640 PSIG operating pressure. DOT vessels are transportable as cargo and can be moved between sites, refilled from tube trailers or bulk sources, and used as mobile or semi-permanent storage; ASME vessels by contrast are typically fixed installations. The DOT 3AA specification indicates seamless carbon steel construction suitable for high-pressure compressed gas service including nitrogen, argon, and helium as stated in the listing.

What is the MAWP and capacity at service pressure?

The MAWP is 2,400 PSIG, and with the 10% overfill stamp the operating pressure is 2,640 PSIG. The listing states 122 cubic feet water volume with a flow capacity of 20,000 SCF—verify with the seller whether that SCF rating is at the 2,400 PSIG design pressure or the 2,640 PSIG operating pressure, as that distinction affects how much usable gas you'll have at your facility's delivery pressure.

What is the requalification or inspection status?

Hydrostatic retest is due 11-17-27, meaning the unit is currently in-service and valid through that date. DOT 3AA tube banks typically require hydrostatic requalification every five years, so plan for that expense and downtime cycle if you're evaluating long-term use.

What should I inspect before putting it into service?

Verify the DOT stampings and serial numbers match the retest documentation, inspect all manifold connections and valves for corrosion or damage, and check the skid frame for structural integrity given the 15,000 lb weight. Request the complete retest records and any service history, confirm what gas was last stored (the listing indicates nitrogen service but previous contamination can limit future use), and have a qualified inspector pressure-test the system and verify all pressure relief devices are within their service dates.