# HS chapter 84: Nuclear reactors, boilers, machinery and mechanical appliances; parts thereof (page 6 of 6) > HS chapter 84 covers nuclear reactors, boilers, machinery and mechanical appliances; parts thereof. It has 86 headings, 84.01 to 84.87, and 538… Page 6 of 6. Source: https://border.bot/hs-codes/84?page=6 Last updated: 11 October 2026 [HS codes](https://border.bot/hs-codes) / [Chapter 84](https://border.bot/hs-codes/84) Page 6 of 6: subheadings 501 to 538 of 538. Previous page: [page 5](https://border.bot/hs-codes/84?page=5). ## Key facts - Chapter: 84 - Description: Nuclear reactors, boilers, machinery and mechanical appliances; parts thereof - Headings: 86 - Subheadings: 538 - Edition: HS2022 ## What this chapter covers HS chapter 84 covers nuclear reactors, boilers, machinery and mechanical appliances; parts thereof. It has 86 headings, 84.01 to 84.87, and 538 six-digit subheadings in HS2022. ### [84.80](https://border.bot/hs-codes/8480) Moulding boxes for metal foundry; mould bases; moulding patterns; moulds for metal (other than ingot moulds), metal carbides, glass, mineral materials, rubber or plastics - [8480.71](https://border.bot/hs-codes/848071) Moulds for rubber or plastics: Injection or compression types - [8480.79](https://border.bot/hs-codes/848079) Moulds for rubber or plastics: Other ### [84.81](https://border.bot/hs-codes/8481) Taps, cocks, valves and similar appliances for pipes, boiler shells, tanks, vats or the like, including pressure-reducing valves and thermostatically controlled valves - [8481.10](https://border.bot/hs-codes/848110) Pressure-reducing valves - [8481.20](https://border.bot/hs-codes/848120) Valves for oleohydraulic or pneumatic transmissions - [8481.30](https://border.bot/hs-codes/848130) Check (nonreturn) valves - [8481.40](https://border.bot/hs-codes/848140) Safety or relief valves - [8481.80](https://border.bot/hs-codes/848180) Other appliances - [8481.90](https://border.bot/hs-codes/848190) Parts ### [84.82](https://border.bot/hs-codes/8482) Ball or roller bearings - [8482.10](https://border.bot/hs-codes/848210) Ball bearings - [8482.20](https://border.bot/hs-codes/848220) Tapered roller bearings, including cone and tapered roller assemblies - [8482.30](https://border.bot/hs-codes/848230) Spherical roller bearings - [8482.40](https://border.bot/hs-codes/848240) Needle roller bearings, including cage and needle roller assemblies - [8482.50](https://border.bot/hs-codes/848250) Other cylindrical roller bearings, including cage and roller assemblies - [8482.80](https://border.bot/hs-codes/848280) Other, including combined ball/roller bearings - [8482.91](https://border.bot/hs-codes/848291) Parts: Balls, needles and rollers - [8482.99](https://border.bot/hs-codes/848299) Parts: Other ### [84.83](https://border.bot/hs-codes/8483) Transmission shafts (including cam shafts and crank shafts) and cranks; bearing housings and plain shaft bearings; gears and gearing; ball or roller screws; gear boxes and other speed changers, including torque converters; flywheels and pulleys, including pulley blocks; clutches and shaft couplings (including universal joints) - [8483.10](https://border.bot/hs-codes/848310) Transmission shafts (including cam shafts and crank shafts) and cranks - [8483.20](https://border.bot/hs-codes/848320) Bearing housings, incorporating ball or roller bearings - [8483.30](https://border.bot/hs-codes/848330) Bearing housings, not incorporating ball or roller bearings; plain shaft bearings - [8483.40](https://border.bot/hs-codes/848340) Gears and gearing, other than toothed wheels, chain sprockets and other transmission elements presented separately; ball or roller screws; gear boxes and other speed changers, including torque converters - [8483.50](https://border.bot/hs-codes/848350) Flywheels and pulleys, including pulley blocks - [8483.60](https://border.bot/hs-codes/848360) Clutches and shaft couplings (including universal joints) - [8483.90](https://border.bot/hs-codes/848390) Toothed wheels, chain sprockets and other transmission elements presented separately; parts ### [84.84](https://border.bot/hs-codes/8484) Gaskets and similar joints of metal sheeting combined with other material or of two or more layers of metal; sets or assortments of gaskets and similar joints, dissimilar in composition, put up in pouches, envelopes or similar packings; mechanical seals - [8484.10](https://border.bot/hs-codes/848410) Gaskets and similar joints of metal sheeting combined with other material or of two or more layers of metal - [8484.20](https://border.bot/hs-codes/848420) Mechanical seals - [8484.90](https://border.bot/hs-codes/848490) Other ### [84.85](https://border.bot/hs-codes/8485) Machines for additive manufacturing - [8485.10](https://border.bot/hs-codes/848510) By metal deposit - [8485.20](https://border.bot/hs-codes/848520) By plastics or rubber deposit - [8485.30](https://border.bot/hs-codes/848530) By plaster, cement, ceramics or glass deposit - [8485.80](https://border.bot/hs-codes/848580) Other - [8485.90](https://border.bot/hs-codes/848590) Parts ### [84.86](https://border.bot/hs-codes/8486) Machines and apparatus of a kind used solely or principally for the manufacture of semiconductor boules or wafers, semiconductor devices, electronic integrated circuits or flat panel displays; machines and apparatus specified in Note 11 (C) to this Chapter; parts and accessories - [8486.10](https://border.bot/hs-codes/848610) Machines and apparatus for the manufacture of boules or wafers - [8486.20](https://border.bot/hs-codes/848620) Machines and apparatus for the manufacture of semiconductor devices or of electronic integrated circuits - [8486.30](https://border.bot/hs-codes/848630) Machines and apparatus for the manufacture of flat panel displays - [8486.40](https://border.bot/hs-codes/848640) Machines and apparatus specified in Note 11 (C) to this Chapter - [8486.90](https://border.bot/hs-codes/848690) Parts and accessories ### [84.87](https://border.bot/hs-codes/8487) Machinery parts, not containing electrical connectors, insulators, coils, contacts or other electrical features, not specified or included elsewhere in this Chapter - [8487.10](https://border.bot/hs-codes/848710) Ships' or boats' propellers and blades therefor - [8487.90](https://border.bot/hs-codes/848790) Other ## What it doesn’t cover Chapter 83, before it, covers miscellaneous articles of base metal; chapter 85, after it, covers electrical machinery and equipment and parts thereof; sound recorders and reproducers, television image and sound recorders and reproducers, and parts and accessories of such articles. ## How it is structured Chapter 84 is the first level of the Harmonized System. Its headings add two digits to the chapter number (84.01), and each heading's subheadings add two more. ## In other countries National tariff lines under chapter 84 are live on border.bot for the United States (1,706 lines, also used by 1 other country). - [United States](https://border.bot/countries/united-states/hs-codes/84): 1,706 lines, used by 1 other country Page 6 of 6: subheadings 501 to 538 of 538. Previous page: [page 5](https://border.bot/hs-codes/84?page=5). - Previous chapter: [83](https://border.bot/hs-codes/83) Miscellaneous articles of base metal - Next chapter: [85](https://border.bot/hs-codes/85) Electrical machinery and equipment and parts thereof; sound recorders and reproducers, television image and sound recorders and reproducers, and parts and accessories of such articles ## Frequently asked questions ### What does HS chapter 84 cover? HS chapter 84 covers nuclear reactors, boilers, machinery and mechanical appliances; parts thereof. ### How many headings and subheadings are in HS chapter 84? HS chapter 84 has 86 headings and 538 six-digit subheadings in HS2022. ### Which countries’ tariffs list national lines in HS chapter 84? National tariff lines under chapter 84 are live on border.bot for the United States (1,706 lines, also used by 1 other country). ## Sources and updates The Harmonized System legal text comes from border.bot release 2 (edition HS 2022), imported from a file, and has been live since 11 October 2026. This page was last updated on 11 October 2026. Guidance from published tariff data, not a binding ruling. For a decision customs must follow, apply to the destination’s customs authority for a binding tariff ruling. Machine-readable: https://border.bot/hs-codes/84.json?page=6