Superior 10,450 Gallon NH3 Transport Trailer

Description

The Superior 10,450 gallon NH3 transport trailer is a DOT MC-331 cargo tank built for anhydrous ammonia — the standard vessel for moving NH3 from a terminal to an agricultural co-op or a process plant. Like the propane tanks that make up most of our catalogue, it is a welded steel pressure vessel holding a liquefied gas under its own vapour pressure, and it is built, inspected and requalified to the same family of standards. Listed at $45,000.

Superior NH3 Transport Specifications

• Capacity: 10,450 US gallons
• Specification: DOT MC-331 cargo tank
• Maximum working pressure: 265 PSI
• Minimum design temperature: -20°F
• Shell thickness: approximately 0.390-0.401 in
• Head thickness: 0.250 in, hemispherical heads
• Outside diameter: approximately 84.8-86.8 in
• Overall length: approximately 463 in
• Material: pressure-vessel-quality carbon steel plate (ASTM A612 Gr. B or A516 Gr. 65/70 per 49 CFR 178.337-2)
• Pump: Blackmer transfer pump
• Instrumentation: tank volume gauge
• Running gear: tandem axle, spring suspension, aluminium rims and fenders
• Registration: National Board registered; build years typically 1964-1966
• Price: $45,000

What the 265 PSI Rating Means

Anhydrous ammonia at 100°F sits at roughly 197 psig vapour pressure, so a 265 PSI maximum allowable working pressure gives the margin a hot summer day on a black asphalt yard demands. This is why NH3 transports are heavy-wall vessels with hemispherical heads rather than the thin-wall dished construction of an atmospheric tanker — the shape and the thickness are both doing structural work.

Age, Inspection and Requalification

These trailers are from the 1960s, and that is normal for the class rather than a warning sign. An MC-331 cargo tank is not retired by age; it is retired when it fails a test. It stays in service on a schedule of external visual inspections, internal inspections, thickness testing and periodic pressure tests, all recorded against its National Board number. Sixty-year-old NH3 transports in daily commercial use are common. What you must do is confirm the current test dates before purchase, and budget for the next requalification — ask us for the inspection paperwork on the specific unit.

The Blackmer Pump

Blackmer sliding vane pumps are the industry standard for NH3 and LPG transfer, and the reason is that they handle a liquefied gas that flashes to vapour at the slightest pressure drop without losing prime or cavitating itself to pieces. A transport without a working pump is a transport that can only gravity-discharge, which in practice means it cannot do its job.

Compliance

NH3 is a hazardous material. Transport is governed by 49 CFR, the driver needs a hazmat endorsement, and loading and unloading require the correct personal protective equipment and emergency procedures. We supply the equipment and its documentation; running the compliance programme is the operator’s responsibility.

Freight

This is an oversize load requiring a suitably rated tractor. It can be collected from our yard or delivered — contact us for a delivered price to your ZIP code. Compare with the Lubbock 10,400 gallon transport.