Chapter 73 covers articles of iron or steel, but excludes specific mechanical, vehicle, aircraft and other parts made of iron or steel (classified in Chapters 84-88). This chapter includes various articles further worked from primary iron or steel products (such as bars, plates, tubes), such as structural components, containers, springs, chains, fasteners, etc. Spring washers, as a type of iron or steel fastener, are a typical commodity of this chapter. Heading 7318 covers screws, bolts, nuts, washers, rivets, pins, cotter pins, spring washers and other similar fasteners of iron or steel. These goods are typically used for mechanical connection or fastening, and the material is iron or steel (including cast iron, alloy steel, etc.). Spring washers are separately named due to their anti-loosening function, and are distinguished from ordinary washers (7318.22). First 2 digits 73: indicates Chapter 73 "Articles of iron or steel". Digits 3-4: 18 indicates heading 7318 "Screws, bolts, nuts, washers, rivets, pins, cotter pins, spring washers and similar articles of iron or steel". Digits 5-6: 21 indicates subheading 7318.21 "Spring washers and other lock washers". This subheading further distinguishes spring washers and lock washers, which have similar functions, both used to prevent nuts from loosening. Spring washers are elastic and can generate tension through deformation to prevent bolts from loosening, and belong to lock washers. They are different from ordinary flat washers (7318.22), which are only used to distribute pressure and have no anti-loosening function. They are also different from other lock washers (such as toothed washers), but if their material is iron or steel and they are used for fastening, they are still classified under 7318.21.
Chapter
Chapter 73 covers articles of iron or steel, but excludes specific mechanical, vehicle, aircraft and other parts made of iron or steel (classified in Chapters 84-88). This chapter includes various articles further worked from primary iron or steel products (such as bars, plates, tubes), such as structural components, containers, springs, chains, fasteners, etc. Spring washers, as a type of iron or steel fastener, are a typical commodity of this chapter.
Heading
Heading 7318 covers screws, bolts, nuts, washers, rivets, pins, cotter pins, spring washers and other similar fasteners of iron or steel. These goods are typically used for mechanical connection or fastening, and the material is iron or steel (including cast iron, alloy steel, etc.). Spring washers are separately named due to their anti-loosening function, and are distinguished from ordinary washers (7318.22).
Digit Breakdown
First 2 digits 73: indicates Chapter 73 "Articles of iron or steel". Digits 3-4: 18 indicates heading 7318 "Screws, bolts, nuts, washers, rivets, pins, cotter pins, spring washers and similar articles of iron or steel". Digits 5-6: 21 indicates subheading 7318.21 "Spring washers and other lock washers". This subheading further distinguishes spring washers and lock washers, which have similar functions, both used to prevent nuts from loosening.
Classification Basis
Spring washers are elastic and can generate tension through deformation to prevent bolts from loosening, and belong to lock washers. They are different from ordinary flat washers (7318.22), which are only used to distribute pressure and have no anti-loosening function. They are also different from other lock washers (such as toothed washers), but if their material is iron or steel and they are used for fastening, they are still classified under 7318.21.
📝 Declaration Elements
Product Name: The standard name of the declared commodity should use "spring washer" or "spring washer (of iron or steel)", avoiding colloquial names such as "elastic pad". Material: Specify the type of iron or steel, such as "carbon steel", "alloy steel", "stainless steel", etc., and indicate whether surface treatment has been applied (such as galvanizing). Use: Explain the usage scenario, such as "for bolt anti-loosening", "for mechanical connection anti-loosening", reflecting its function. Specifications and Dimensions: Provide main dimensions, such as inner diameter, outer diameter, thickness, usually expressed in millimeters. Brand or Model: If there is a brand or model, it must be declared; if no brand, fill in "no brand". Standard: If it complies with standards such as GB, DIN, ANSI, etc., the standard number should be indicated. Surface Treatment: Such as "galvanized", "blackened", "phosphated", etc., affecting rust prevention performance. Product Name: Spring washer (of iron or steel); Material: Carbon steel, galvanized; Use: For bolt anti-loosening; Specifications: Inner diameter 8mm, outer diameter 15mm, thickness 2mm; Brand: No brand; Standard: GB/T 93; Surface Treatment: Galvanized. Misdeclaring spring washers as ordinary flat washers (7318.22), leading to classification errors. Material declaration is unclear, such as only writing "metal" without indicating iron or steel, which may affect classification. Use description does not reflect anti-loosening function, may be suspected as other washers.
Product Name
The standard name of the declared commodity should use "spring washer" or "spring washer (of iron or steel)", avoiding colloquial names such as "elastic pad".
⚠️ Incorrectly declaring as "washer" or "spring", leading to classification errors.
Material
Specify the type of iron or steel, such as "carbon steel", "alloy steel", "stainless steel", etc., and indicate whether surface treatment has been applied (such as galvanizing).
⚠️ Only writing "iron or steel" without specific description, which may affect classification.
Use
Explain the usage scenario, such as "for bolt anti-loosening", "for mechanical connection anti-loosening", reflecting its function.
⚠️ Filling in "for machinery" is too general and cannot prove its anti-loosening use.
Specifications and Dimensions
Provide main dimensions, such as inner diameter, outer diameter, thickness, usually expressed in millimeters.
⚠️ Only writing "standard part" or "M8", without providing specific dimensions.
Brand or Model
If there is a brand or model, it must be declared; if no brand, fill in "no brand".
⚠️ Ignoring the brand, resulting in inability to distinguish from similar products.
Standard
If it complies with standards such as GB, DIN, ANSI, etc., the standard number should be indicated.
⚠️ Not providing the standard may affect customs' determination of the product.
Surface Treatment
Such as "galvanized", "blackened", "phosphated", etc., affecting rust prevention performance.
⚠️ Omitting surface treatment, leading to confusion with untreated products.
Example： Product Name: Spring washer (of iron or steel); Material: Carbon steel, galvanized; Use: For bolt anti-loosening; Specifications: Inner diameter 8mm, outer diameter 15mm, thickness 2mm; Brand: No brand; Standard: GB/T 93; Surface Treatment: Galvanized.
Common Mistakes：
Misdeclaring spring washers as ordinary flat washers (7318.22), leading to classification errors.
Material declaration is unclear, such as only writing "metal" without indicating iron or steel, which may affect classification.
Use description does not reflect anti-loosening function, may be suspected as other washers.
🎯 Classification Logic
Core basis for classification: 1) Material is iron or steel; 2) Has elasticity, can generate anti-loosening tension through deformation; 3) Used for fastener anti-loosening. According to the "Import and Export Tariff" and notes, spring washers belong to subheading 7318.21. If the material is not iron or steel (such as copper), then classified under 7415; if plastic, then classified under 3926. 731822 Other washers: Ordinary flat washers, no anti-loosening function, only used to distribute pressure. Spring washers are elastic and can prevent loosening. 731815 Other screws and bolts: Screws and bolts are threaded fasteners, while spring washers are unthreaded washers. 731829 Other unthreaded articles: Includes other unthreaded fasteners, such as pins, cotter pins, etc., but spring washers have a specific subheading. 741521 Copper spring washers: Material is copper, while 731821 is of iron or steel. 392690 Plastic spring washers: Material is plastic, classified under Chapter 39. Is the material iron or steel? Does it have elastic anti-loosening function? Is it unthreaded? Is it used for fastener anti-loosening? Is it distinguished from ordinary flat washers?
Basis
Core basis for classification: 1) Material is iron or steel; 2) Has elasticity, can generate anti-loosening tension through deformation; 3) Used for fastener anti-loosening. According to the "Import and Export Tariff" and notes, spring washers belong to subheading 7318.21. If the material is not iron or steel (such as copper), then classified under 7415; if plastic, then classified under 3926.
Confused Codes：
731822 - Other washers
Ordinary flat washers, no anti-loosening function, only used to distribute pressure. Spring washers are elastic and can prevent loosening.
731815 - Other screws and bolts
Screws and bolts are threaded fasteners, while spring washers are unthreaded washers.
731829 - Other unthreaded articles
Includes other unthreaded fasteners, such as pins, cotter pins, etc., but spring washers have a specific subheading.
741521 - Copper spring washers
Material is copper, while 731821 is of iron or steel.
392690 - Plastic spring washers
Material is plastic, classified under Chapter 39.
Self-Check：
✓ Is the material iron or steel?
✓ Does it have elastic anti-loosening function?
✓ Is it unthreaded?
✓ Is it used for fastener anti-loosening?
✓ Is it distinguished from ordinary flat washers?
❓ FAQ
What is the difference in HS codes between spring washers and ordinary washers? Spring washers are classified under 7318.21, ordinary flat washers under 7318.22. The main difference is function: spring washers are elastic and can prevent bolts from loosening; ordinary washers are only used to distribute pressure and have no anti-loosening function. Which code should stainless steel spring washers be classified under? Stainless steel belongs to iron or steel, so stainless steel spring washers are still classified under 7318.21. However, note that if they are of other alloy steel, they are also classified under the same code. How to determine whether a washer is a spring washer or other lock washer? Spring washers are usually open-ring shaped and elastic; other lock washers such as toothed washers, wedge washers, etc., have different structures but similar functions, and are all classified under 7318.21. What are the most common errors when declaring spring washers? Common errors include: declaring spring washers as ordinary washers (7318.22), or unclear material declaration, such as only writing "metal" without indicating iron or steel. If a spring washer is used in automobiles, is it classified under Chapter 87? No, spring washers as general fasteners, even if used in automobiles, are classified under 7318.21. Chapter 87 only includes parts specifically for automobiles. How to check the tariff rate for spring washers? You can check the "Import and Export Tariff of the People's Republic of China" or use tools such as the General Administration of Customs website, classification tools, etc., by entering code 731821 to query the latest tariff rate. Rates may change, subject to official publication. Are spring washers and elastic washers the same thing? Elastic washer is a broader term, including spring washers and other elastic washers. However, in HS codes, spring washers specifically refer to 7318.21; other elastic washers, if made of iron or steel and used for anti-loosening, are also classified under this code. What declaration elements are required for importing spring washers? Need to provide product name, material, use, specifications and dimensions, brand and model, standard, surface treatment, etc. Specific requirements are subject to customs; it is recommended to refer to the "Standard Declaration Catalog".
Q: What is the difference in HS codes between spring washers and ordinary washers?
A: Spring washers are classified under 7318.21, ordinary flat washers under 7318.22. The main difference is function: spring washers are elastic and can prevent bolts from loosening; ordinary washers are only used to distribute pressure and have no anti-loosening function.
Q: Which code should stainless steel spring washers be classified under?
A: Stainless steel belongs to iron or steel, so stainless steel spring washers are still classified under 7318.21. However, note that if they are of other alloy steel, they are also classified under the same code.
Q: How to determine whether a washer is a spring washer or other lock washer?
A: Spring washers are usually open-ring shaped and elastic; other lock washers such as toothed washers, wedge washers, etc., have different structures but similar functions, and are all classified under 7318.21.
Q: What are the most common errors when declaring spring washers?
A: Common errors include: declaring spring washers as ordinary washers (7318.22), or unclear material declaration, such as only writing "metal" without indicating iron or steel.
Q: If a spring washer is used in automobiles, is it classified under Chapter 87?
A: No, spring washers as general fasteners, even if used in automobiles, are classified under 7318.21. Chapter 87 only includes parts specifically for automobiles.
Q: How to check the tariff rate for spring washers?
A: You can check the "Import and Export Tariff of the People's Republic of China" or use tools such as the General Administration of Customs website, classification tools, etc., by entering code 731821 to query the latest tariff rate. Rates may change, subject to official publication.
Q: Are spring washers and elastic washers the same thing?
A: Elastic washer is a broader term, including spring washers and other elastic washers. However, in HS codes, spring washers specifically refer to 7318.21; other elastic washers, if made of iron or steel and used for anti-loosening, are also classified under this code.
Q: What declaration elements are required for importing spring washers?
A: Need to provide product name, material, use, specifications and dimensions, brand and model, standard, surface treatment, etc. Specific requirements are subject to customs; it is recommended to refer to the "Standard Declaration Catalog".
⚠️ Disclaimer: HS code classification, declaration elements, tariff rates and regulatory conditions on this page are for reference only and do not constitute legal advice on customs classification. Tariff rates and regulations are subject to change; the latest announcements from the General Administration of Customs and on-site determinations shall prevail. Please consult professional customs brokers or customs authorities before import/export.