Product classification

HS code for Large diameter steel casing: 7305.20

Iron or steel (excluding cast iron), casing of a kind used in drilling for oil or gas (not seamless), having circular cross-sections, external diameter exceeds 406.4mm.

Classification of large diameter steel casing under HS 7305.20

Large diameter steel casing is classified under HS code 730520. This code is specifically reserved for iron or steel tubes and pipes that are not seamless, have a circular cross-section, and possess an external diameter exceeding 406.4mm. Furthermore, the product must be specifically designed as "casing" of a kind used in drilling for oil or gas. The classification under heading 7305 (as opposed to 7304 or 7306) is dictated by the combination of the large external diameter and the manufacturing method (welded or riveted). These pipes are critical infrastructure components in the energy sector, designed to withstand high pressure and protect the structural integrity of oil and gas wells during extraction processes.

Covers
  • Welded steel casing (>406.4mm diameter)
  • Submerged arc welded (SAW) casing for oil/gas wells
  • Large diameter longitudinal welded casing
  • Spiral welded steel casing for drilling applications
Also under 7305.20
  • Tenaris API 5CT casing
  • Vallourec large diameter casing
  • JFE Steel casing
  • TMK large diameter casing

Codes often confused with 7305.20

Common mistake. This product is often misclassified under HS code 730422 or 730424, which are for seamless casing. If the pipe has no weld seam, it must go in 7304 regardless of diameter. Another common error is using HS code 730511 or 730512, which are for "line pipe" used for oil or gas pipelines. While casing and line pipe look similar, casing is used inside the wellbore, whereas line pipe is used for transport; they are distinct categories in the HS system.

7304.22Steel, stainless; seamless, drill pipe, of a kind used in drilling for oil or gas7304.24Steel, stainless; seamless, casing and tubing, of a kind used in drilling for oil or gas73.04Tubes, pipes and hollow profiles, seamless, of iron (other than cast iron) or steel7305.11Iron or steel (excluding cast iron); line pipe of a kind used for oil or gas pipelines (not seamless), longitudinally submerged arc welded, having circular cross-sections, external diameter exceeds 406.4mm7305.12Iron or steel (excluding cast iron); line pipe of a kind used for oil or gas pipelines (not seamless), longitudinally welded (not submerged arc welded), having circular cross-sections, external diameter exceeds 406.4mm

Top exporters and importers of HS 730520 (the code used for large diameter steel casing), 2025

In 2025, the largest exporter of HS 730520 (the code used for large diameter steel casing) in UN Comtrade data was Brazil, with 29% of world exports; the largest importer in UN Comtrade data was Guyana, with about 20% of world imports. Countries that did not report 2025 data are estimated from partner records, which can understate them.

Figures cover everything classified under HS 730520, not only large diameter steel casing.

Top exporters 2025 · share of world exports

  1. 1 Brazil $138M
  2. 2 Indonesia $113M
  3. 3 Singapore $84M

World total: $479M Reported figures on UN Comtrade ↗

Top importers 2025 · share of world imports

  1. 1 Guyana* ~$86M
  2. 2 Singapore $67M
  3. 3 Kuwait $53M

World total: $427M Reported figures on UN Comtrade ↗

How these figures are built

109 countries reported 2025 trade to UN Comtrade in HS 2022, and their own totals are used. Countries marked * did not, so their figures add up what other countries recorded trading with them, and their exports are valued at buyers' CIF prices. Those estimates miss trade with other non-reporting countries, so they can be low, and a non-reporting country can rank higher than shown or be missing from the list. World totals add both and leave out trade between two non-reporting countries. Figures are in current US dollars; reported imports are mostly valued CIF and exports FOB, and exports include re-exports. The UN Comtrade links show the underlying records; they can also list a few reporters left out here (regional groups and older HS editions).

Source: UN Comtrade (United Nations Statistics Division), 2025 annual data.

Brazil NCM code for large diameter steel casing

Brazil classifies large diameter steel casing under NCM 7305.20.00: HS 7305.20 with 00 added.

Source: Siscomex NCM table, updated Oct 2026. The Portuguese text on each NCM page is the official one.

EU Regulatory Requirements

This product falls under the Carbon Border Adjustment Mechanism (CBAM). Importers to the EU must declare embedded carbon emissions and purchase CBAM certificates.

Questions about large diameter steel casing

What is the HS code for Large diameter steel casing?

The HS code for Large diameter steel casing is 730520 (Iron or steel (excluding cast iron); casing of a kind used in drilling for oil or gas (not seamless), having circular cross-sections, external diameter exceeds 406.4mm). The HS code for non-seamless steel casing with an external diameter exceeding 406.4mm used in oil or gas drilling is 7305.20.

How do I classify Large diameter steel casing for customs?

Large diameter steel casing is classified under HS code 730520 — Iron or steel (excluding cast iron); casing of a kind used in drilling for oil or gas (not seamless), having circular cross-sections, external diameter exceeds 406.4mm. This is a 6-digit subheading level code.

What if the diameter is less than 406.4mm?

If the external diameter is 406.4mm or less and the pipe is welded, it would be classified under HS code 7306.29.

Which countries are the top exporters of large diameter steel casing (HS 730520)?

In 2025, the top exporters of HS 730520 (the code used for large diameter steel casing) in UN Comtrade data were Brazil ($138M, 29% of world exports), Indonesia ($113M) and Singapore ($84M). World exports came to about $479M, adding countries' reported figures and partner-based estimates for those that did not report (UN Comtrade data). Countries that did not report 2025 data are estimated from partner records, which can understate them.

Which countries are the top importers of large diameter steel casing (HS 730520)?

In 2025, the top importers of HS 730520 (the code used for large diameter steel casing) in UN Comtrade data were Guyana (about $86M, 20% of world imports), Singapore ($67M) and Kuwait ($53M). World imports came to about $427M, adding countries' reported figures and partner-based estimates for those that did not report (UN Comtrade data). Countries that did not report 2025 data are estimated from partner records, which can understate them.

Is the HS code for Large diameter steel casing the same in all countries?

The base HS code 730520 for Large diameter steel casing is internationally standardized for the first 6 digits across 200+ countries. Individual countries may add additional digits for national tariff lines and specific classifications.

What is the NCM code for large diameter steel casing in Brazil?

In Brazil, large diameter steel casing (HS 730520) is classified under NCM 7305.20.00.