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T/P91 Grade 91 Seamless Heat Exchanger Tube

Grade 91 (9Cr-1Mo-V) seamless alloy steel tube, 140 mm OD, engineered for high-temperature heat exchangers and feedwater heaters in fossil fuel plants. Provides excellent creep strength and oxidation resistance. Under 7304.59.20.55 for its alloy composition, seamless construction, and suitability for heat exchangers with OD 114.3-190.5 mm.

Import Duty Rates by Country of Origin

Origin CountryMFN RateCh.99 SurchargesTotal Effective Rate
🇨🇳ChinaFree+35.0%35%
🇲🇽MexicoFree+10.0%10%
🇨🇦CanadaFree+10.0%10%
🇩🇪GermanyFree+10.0%10%
🇯🇵JapanFree+10.0%10%

Alternative Classifications

This product could be classified differently depending on its characteristics or intended use.

7304.51.10.00Same rate: 35%

If of carbon steel rather than alloy

Carbon steel seamless tubes (less than 0.2% alloy elements) fall under 7304.51, excluding alloy steel.

7304.59.20Same rate: 35%

If OD between 60.3 mm and 114.3 mm

Precise OD ranges dictate subheadings within suitable-for-boiler tubes.

8402.90.00Higher: 39.3% vs 35%

If supplied as components in boiler sets

Tubes sold as part of complete boiler assemblies classify under boiler parts heading.

Not sure which classification is right?

Our AI classifier can analyze your specific product and recommend the correct HTS code with confidence.

Import Tips & Compliance

Confirm normalizing/tempering heat treatment per ASTM A335; include dimensional inspection reports

Avoid pitfall of bulk packaging misclassified as scrap metal