Nonalloy Steel Boiler Flue Pipes
Seamless thin-walled pipes of iron or nonalloy steel designed for conveying hot gases in boiler systems. Wall thickness less than 4 mm qualifies them for HTS 7304.90.50.00 as seamless hollow profiles of nonalloy steel.
Import Duty Rates by Country of Origin
Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If wall thickness 4mm or greater
Thicker-walled seamless pipes of nonalloy steel move to 7304.90.30.00 subheading.
If when imported with mechanical fittings as a set
Tube or pipe fittings of iron/nonalloy steel classify separately if combined for assembly.
If for use exclusively in steam boilers
Parts specifically for boilers may fall under Chapter 84 as boiler components.
Not sure which classification is right?
The Tariff Assistant works through the GRI rules on your specific product to reach the right HTS code — and can price the duty on it in the same conversation.
Import Tips & Compliance
• Provide pressure test reports confirming suitability for high-temperature use without reclassifying as line pipe
• Declare exact outer diameter and wall thickness to match statistical suffixes accurately
• Avoid bundling with fittings, as sets may classify under 7307 for tube fittings
Related Products under HTS 7304.90.50.00
Seamless Steel Hydraulic Tubing
Thin-walled seamless tubes of nonalloy steel used in hydraulic systems for machinery and equipment. These pipes have a wall thickness under 4 mm and are classified under HTS 7304.90.50.00 due to their seamless construction from iron or nonalloy steel, distinguishing them from welded pipes.
Seamless Steel Medical Gas Pipes
Thin-walled seamless nonalloy steel pipes (<4 mm) certified for medical oxygen and gas delivery systems. HTS 7304.90.50.00 covers these clean, seamless tubes of iron/nonalloy steel.
Precision Seamless Steel Instrument Tubing
High-precision seamless tubes of nonalloy steel with wall thickness under 4 mm, used for instrumentation and control lines in industrial applications. Fits HTS 7304.90.50.00 for seamless, thin-walled iron/nonalloy steel pipes.
Automotive Seamless Steel Brake Lines
Seamless nonalloy steel tubes with thin walls (<4 mm) for hydraulic brake systems in vehicles. Classified in HTS 7304.90.50.00 as seamless pipes of iron/nonalloy steel, not as vehicle parts.
Industrial Seamless Steel Condenser Tubes
Thin-walled seamless pipes of nonalloy steel (<4 mm wall) for heat exchanger condensers in power plants. HTS 7304.90.50.00 applies to these seamless hollow profiles of iron/nonalloy steel.
Nonalloy Steel Furniture Frame Tubes
Seamless thin-walled tubes (<4 mm) of nonalloy steel used in metal furniture construction like chair and table legs. HTS 7304.90.50.00 covers these as seamless pipes suitable for structural hollow profiles.