Alloy Steel Socket Weld Flange 4 Inch
Socket weld flange of low-alloy steel, 4-inch nominal size (ID ~102 mm), for high-pressure instrumentation lines. Falls under HTS 7307.91.50.30 as non-stainless alloy steel flange less than 360 mm ID. Pipe inserts into socket and is fillet welded.
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Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If classified as a butt-weld elbow instead of flange
Shape and function determine flange vs elbow/other fitting subheadings.
If stainless steel version
Stainless excludes from alloy steel (except stainless) provisions.
If sold in sets with bolts/nuts for retail
Assembled flange sets with accessories may classify under 'other' with different statistical notes.
Not sure which classification is right?
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Import Tips & Compliance
• Document socket depth and counterbore specs for fitting classification; ensure not declared as elbow (7307.93)
• Test for alloy elements like chromium under 11.5%
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