ILJIN Type 4 CNG Tank – 3600 PSI | DOT FMVSS 304 | 35GGE

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

This tank is DOT FMVSS 304 rated and built to NGV2-2007 standards, which certifies it for compressed natural gas vehicle fuel systems. It is designed for onboard high-pressure fuel storage on CNG vehicles, not stationary storage or ASME-code applications. The DOT FMVSS 304 certification is specific to automotive use and carries different inspection and service life requirements than ASME pressure vessels.

What is the MAWP and capacity at service pressure?

The service pressure is 3,600 PSI (24,800 kPa at 70°F), and the capacity is 35 GGE (gasoline gallon equivalent). Type 4 composite cylinders are typically rated with service pressure as the maximum allowable working pressure, though you should confirm the exact MAWP marking on the cylinder label. The listing does not provide water capacity or physical dimensions.

What should I inspect before putting it into service?

Inspect the composite overwrap for impact damage, gouges, cuts, abrasion, discoloration from heat or chemical exposure, and any delamination or fiber exposure. Check the boss area and valve threads for cracks or corrosion, verify all labels and markings are legible, and confirm the cylinder is within its service life (December 2034 for this unit). Type 4 cylinders are particularly sensitive to impact and UV damage, and any compromise to the composite structure can render the cylinder unserviceable regardless of age.