HS Code Subheading

Iron or steel; non-threaded spring washers and other lock washers

7318.21 Subheading
Section XV — Base metals and articles of base metal

About HS Code 731821

This category covers non-threaded washers specifically designed to prevent loosening of bolted joints due to vibration, thermal expansion, or dynamic loads. Spring washers, with their inherent elasticity, and various lock washers, which create friction or a mechanical lock, are critical components in ensuring the long-term integrity and safety of assemblies across numerous industries. They are essential in maintaining the preload of a bolted joint, thereby preventing catastrophic failures. International trade in these items is driven by global manufacturing, particularly in automotive, aerospace, heavy machinery, and construction sectors where fastener reliability is paramount. Importers are typically assembly plants, MRO suppliers, and hardware distributors. Exporters are specialized manufacturers of industrial fasteners and components, often leveraging advanced material science and precision engineering to meet stringent performance requirements. Key considerations for trade include material grade (e.g., carbon steel, stainless steel), finish (e.g., zinc plated, phosphated), specific design (e.g., split lock, external tooth, internal tooth), and compliance with international standards like DIN and ANSI.

Products Under This Code

Split lock washers, external tooth lock washers, internal tooth lock washers, conical spring washers, wave washers, Belleville washers, serrated lock washers

Real World Examples

Nord-Lock washers, Schnorr disc springs, Fastenal lock washers, Würth spring washers

Common Misclassification

Can be confused with 731822 (other non-threaded washers) if the locking or spring function is not clearly identified, as 731821 specifically covers those designed for locking.

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.

Products Classified Under 7318.21

Industry

This code belongs to the Automotive & Vehicles industry.

Trade Overview

China, Germany, and the USA are key players in both the import and export of these essential locking components.

Frequently Asked Questions

What is HS code 731821?

HS code 731821 covers: Iron or steel; non-threaded spring washers and other lock washers. This category covers non-threaded washers specifically designed to prevent loosening of bolted joints due to vibration, thermal expansion, or dynamic loads. Spring washers, with their inherent elasticity, and various lock washers, which create friction or a mechanical lock, are critical components in ensuring the long-term integrity and safety of assemblies across numerous industries. They are essential in maintaining the preload of a bolted joint, thereby preventing catastrophic failures. International trade in these items is driven by global manufacturing, particularly in automotive, aerospace, heavy machinery, and construction sectors where fastener reliability is paramount. Importers are typically assembly plants, MRO suppliers, and hardware distributors. Exporters are specialized manufacturers of industrial fasteners and components, often leveraging advanced material science and precision engineering to meet stringent performance requirements. Key considerations for trade include material grade (e.g., carbon steel, stainless steel), finish (e.g., zinc plated, phosphated), specific design (e.g., split lock, external tooth, internal tooth), and compliance with international standards like DIN and ANSI.

What products fall under HS code 731821?

Split lock washers, external tooth lock washers, internal tooth lock washers, conical spring washers, wave washers, Belleville washers, serrated lock washers

What are common misclassifications for HS code 731821?

Can be confused with 731822 (other non-threaded washers) if the locking or spring function is not clearly identified, as 731821 specifically covers those designed for locking.

How is HS code 731821 structured?

HS code 731821 is a 6-digit subheading under the Harmonized System. The first 2 digits (73) identify the chapter, digits 3-4 (18) identify the heading, and digits 5-6 (21) specify the subheading. This code is standardized globally by the World Customs Organization.