Chapter 84 is the core chapter in HS classification covering machinery and mechanical appliances, including power machinery, pumps, compressors, valves, bearings, transmission devices, etc. Goods in this chapter are mostly industrial basic components, and classification requires consideration of function, working principle, and use. Heading 8481 specifically refers to valves and similar devices for pipes, boilers, tanks, etc., which are key components for fluid control. Heading 8481 covers valves, cocks, taps and similar devices for pipes, boilers, tanks, vats or similar containers, including pressure-reducing valves, check valves, safety valves, relief valves, etc. This heading includes not only manual valves but also automatically controlled valves, but care must be taken to distinguish them from 8482 bearings and 8483 transmission devices. The first 2 digits 84 represent Chapter 84 machinery; digits 3-4, 81, indicate heading 8481, i.e., valves and similar devices; digits 5-6, 30, are the subheading, specifically referring to check valves. A check valve is a valve that opens and closes automatically by the flow of the fluid itself, used to prevent backflow. Subheading 8481.30 specifically refers to check valves; regardless of material, drive method, or use, as long as it meets the definition of a check valve, it is classified under this code. The function of a check valve is to prevent fluid backflow. It is an automatic valve whose opening and closing are controlled by fluid pressure difference without external power. This distinguishes it from other subheadings under 8481 such as pressure-reducing valves (8481.10), safety valves (8481.40), etc., based on different functions. At the same time, if a check valve is integrated with a pipe or is a part of a specific machine, it may be classified according to the machine, but when presented separately, it is classified under 8481.30.

Product Name: The Chinese and English names of the declared goods should accurately reflect the product attributes, such as '止回阀 Check Valve'. Material: List the materials of the main components such as the valve body and disc, such as cast iron, stainless steel, brass, plastic, etc. Use: Explain the usage scenario, such as for water pipes, oil pipes, boilers, chemical pipes, etc., as well as the controlled medium (water, oil, gas). Working Principle: Briefly describe the opening and closing method of the check valve, such as lift type, swing type, butterfly type, etc., emphasizing automatic opening and closing by fluid pressure. Brand and Model: Provide the brand and model to facilitate identification of the specific product; if there is no brand, write 'None'. Nominal Diameter: The caliber size of the valve, usually expressed as DN, such as DN50. Pressure Rating: The nominal pressure of the valve, such as PN16, Class150, etc. Product Name: 止回阀 Check Valve; Material: valve body stainless steel, disc stainless steel, sealing ring rubber; Use: used in chemical pipelines, controlled medium is water; Working Principle: swing type, automatically opens and closes by fluid pressure; Brand: XYZ; Model: CV-100; Nominal Diameter: DN50; Pressure Rating: PN16. Mistakenly classifying check valves under 8481.80 (other valves), ignoring their dedicated subheading. Failure to specify the working principle, leading to confusion with pressure-reducing valves or safety valves. Incomplete material declaration, affecting customs determination of commodity value.

The core basis for classification is the function of the check valve: automatically opening and closing by the fluid's own pressure to prevent backflow. According to HS notes, check valves are classified under 8481.30 regardless of material or structure. However, if a check valve is assembled with a machine or equipment and becomes an integral part thereof, it may be classified according to the machine (such as check valves for pumps under 8413). Check valves presented separately are always classified under 8481.30. 8481.10 Pressure-reducing valves: Pressure-reducing valves are used to regulate fluid pressure to a set value and have a pressure-regulating function; check valves only prevent backflow and do not regulate pressure. 8481.40 Safety valves or relief valves: Safety valves open to release pressure when pressure exceeds a set value, while check valves only allow one-way flow and have no pressure relief function. 8481.80 Other valves: This subheading is a residual provision, including ball valves, gate valves, etc., but check valves have a dedicated subheading and should not be classified here. 8413.20 Hand pumps: Hand pumps are pump equipment, while check valves are valves; their functions are different. If a hand pump has a check valve, the whole is classified as a hand pump. 8482.10 Bearings: Bearings are used to support shafts, while check valves are used to control fluids; their functions are completely different. Is it clear that the product is a check valve, not another type of valve? Is it presented separately, rather than assembled with a machine? Have the working principle and use been declared? Have the material and specifications been provided? Has it been confirmed that it is not classified under other subheadings of 8481?

Are check valves and one-way valves the same thing? Is the HS code the same? Check valves and one-way valves are the same type of valve, both called Check Valve in English, and both function to prevent fluid backflow. Both are classified under HS code 8481.30. When declaring, it is recommended to use '止回阀' as the product name and indicate the English Check Valve. How can I check the import tariff rate for check valves? The tariff rate must be checked according to the customs tariff of the destination country. For imports into China, consult the 'Import and Export Tariff of the People's Republic of China', or check through the General Administration of Customs website or the single window. Note that tariff rates may vary due to free trade agreements, origin, etc., and the latest tariff schedule should prevail. Which declaration elements for check valves are mandatory? Product name, material, use, working principle, brand and model, nominal diameter, and pressure rating must be filled in. Among these, working principle and use are key to distinguishing classification, and material affects customs valuation. Are the HS codes for stainless steel check valves and cast iron check valves the same? Yes, both are classified under 8481.30. The HS code does not distinguish by material, but material is a declaration element that affects customs valuation and statistics. If a check valve is used in an automobile engine, is it classified under 8481.30? If presented separately, it is still classified under 8481.30. However, if presented together with the engine as an engine part, it may be classified as an engine part (such as 8409). Judgment must be based on the state of presentation. What should be noted when exporting check valves with regard to HS codes? When exporting, confirm whether the destination country's code is the same; some countries may subdivide it. When declaring, provide accurate product name, material, use, etc., to avoid customs clearance delays caused by classification errors. Is there a difference in HS codes between check valves and butterfly check valves? No difference. Butterfly check valves are a type of check valve structure and are still classified under 8481.30. When declaring, 'butterfly type' can be noted in the working principle. If a check valve has an electric actuator, is it still classified under 8481.30? If the electric actuator is only used to assist opening and closing, but the valve itself is still a check valve, then it is classified under 8481.30. If the actuator gives the valve a regulating function, it may be classified under 8481.80 or another subheading. Judgment should be based on the main function.