100 GGE Back of the cab CNG Tank Packages, Type 4 cabron cylinders Lincoln Haxagon / Agility

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

These tanks are DOT rated for on-road vehicle use as CNG or RNG fuel systems. DOT certification allows you to install them on Class 8 trucks or other on-highway vehicles, but they cannot be used as stationary storage, which would require ASME pressure vessel certification. The listing confirms they meet DOT on-road safety standards and were previously used as truck fuel tanks.

What is the MAWP and capacity at service pressure?

The pressure rating is 3,600 PSI, and each three-tank package has a total capacity of 100 GGE (1,413 liters total). Individual tanks are model RL 36A21 with 29.7 GGE (353.5 liters) capacity each, measuring 21" x 86". The listing does not specify whether 3,600 PSI is the MAWP or the service pressure; you should ask the seller to confirm the marked MAWP and whether the capacity rating is at full MAWP or at a lower service pressure.

What is the requalification or inspection status?

The tanks were visually inspected after removal and are stated to have approximately 10 years of service life remaining on a 20-year total design life. Type 4 carbon composite cylinders typically require periodic DOT requalification inspections, but the listing does not specify when the last inspection was performed or when the next is due. Ask the seller for the manufacture date stamps, the most recent inspection records, and whether current DOT requalification is included or needs to be arranged.

What should I inspect before putting it into service?

Visually inspect the carbon fiber overwrap for impact damage, abrasion, cuts, or UV degradation, and check the boss assemblies and valve connections for cracks or thread damage. The listing notes that some small fueling system components may be missing, so verify that all necessary valves, pressure relief devices, mounting hardware, and piping components are present or accounted for in your installation plan. On Type 4 cylinders, also inspect the liner condition through the valve opening if accessible, and confirm that the manufacture date and DOT markings are legible for compliance documentation.