Downcomer Pipe Assembly
Downcomer pipes circulate unheated water from steam drum to boiler lower headers in natural circulation systems. HTS 8402.90.00 covers these dedicated circulation components. Heavy wall seamless construction.
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More Specific Codes
This product may fall under a more specific subheading:
Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If standard seamless steel pipes
Generic pressure piping not boiler-specific goes to Chapter 73 tubes.
If basic pipe fittings
Pipe connectors without circulation function classified as fittings.
Not sure which classification is right?
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Import Tips & Compliance
• Calculate pipe sizing for circulation rates; hydrotest at 1.5x MAWP; ensure seamless construction certification
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