NMFC 51050 - Steel Power Boiler Ducts | Class 150

Note 51052: NOTE-Will also apply on structural steel necessary for erection or installation.

To find the correct freight class for your shipment:

1. List on the BOL as “Steel power boiler ducts, 10 ga or thicker, single side seam (closed or not), NMFC 51050, Class 150” and note if shipping loose or packaged.
2. For loose sections, band to skids or A‑frames with edge protectors and wood dunnage; cap sharp flanges to prevent punctures in mixed LTL trailers.
3. Bundle or crate packaged runs by diameter/segment, and clearly mark longest dimension; while class is fixed, carriers still require accurate dims and weights for capacity planning.
4. Review the Note at item 51052 to confirm acceptable seam condition and construction details, then photograph packed units to document compliance and reduce reclass risk.

Note: All classifications are subject to Item 170. Verify with official NMFC publications for the most current requirements.

• Fixed Class 150 rating eliminates density calculations, speeding quotes and reducing reclass disputes on heavy-gauge steel ducting.
• Allows shipment loose or packaged, giving fabricators flexibility to load large or irregular sections without extra repack costs.
• Non-hazardous status simplifies paperwork and avoids hazmat surcharges, improving landed cost on industrial site deliveries.
• Durable 10 ga+ steel reduces damage frequency, helping OEMs and boiler contractors cut claim costs and schedule delays.