304/316 Stainless Steel Flat Washers Large & Extra Large Fender Washers DIN 9021 Standard for Screw Bolt Fastening
Manufacturing Process
• Multi Station Cold Heading Technology
• Intelligent Heat Treatment System
• Micron-Level Thread Rolling Process
• Fully Automatic Optical Sorting
• Environmentally Friendly Surface Treatment Line
• Metallographic And Mechanical Joint Laboratory
Quality Control System
• Raw Material Source Locking
• Furnace Number Batch Full Traceability
• Third Party Material Certification
• Process Parameters Open And Transparent
• Salt Spray Test Real Time Monitoring
• International Standard Compliance Declaration
Flexible Customization Capability
• Customizable head/slot Shapes
• Extreme Application Of Special Materials
• Breakthroughs In Extra Large/Long Specifications
• Integrated Assembly Of Components
• Customizable Surface Treatment Colors
• Personalized Packaging And Labeling
Technical Service
• On-Site Failure Analysis
• Selection Calculation And BOM Optimization
• Installation Tool Selection Guidance
• Inventory Management (VMI) Trusteeship
• Free Sample Making And Testing
• International Standard Translation And Interpretation
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Multi-Material & Full-Size Options for Durability in All Conditions
Our flat washers (including extra-large fender washers) are available in 304/316 stainless steel (A2/A4) and Q235 carbon steel (grades 4.8/8.8). Polished and passivated stainless steel offers natural corrosion resistance for outdoor and marine environments, while galvanized carbon steel provides cost-effective rust protection. With inner diameters from M2 to M64 and customizable outer diameters and thicknesses, they meet diverse fastening needs for construction, automotive, and mechanical equipment applications.
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Oversized Outer Diameter for Enhanced Pressure Distribution & Surface Protection
Manufactured to DIN 9021 and GB/T 97.1 standards, the oversized outer diameter significantly increases contact area compared to standard washers, effectively distributing clamping pressure to prevent damage or pull-through of soft materials, thin sheets, or slotted holes. Precision inner holes ensure a perfect fit with bolts, while smooth, burr-free surfaces provide uniform load distribution for reliable performance in automotive fenders, outdoor structures, and other applications.
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Tool-Free Installation & Versatility for Bulk Assembly
These washers install easily by placing them under the nut or bolt head without special tools, simplifying assembly and improving efficiency. Stainless steel versions perform well in humid, salt spray environments, while carbon steel options offer excellent wear and corrosion resistance. Widely used in construction, automotive, mechanical equipment, and general assembly, they are ideal for procurement, wholesale, and bulk factory supply with complete specifications and custom options available.
Application Scenarios
Industrial Capabilities
• Factory Area: 8,000 square meters
• Certifications: ISO, IATF, CE, RoHS, JIS, ASTM
• Manufacturing : 70+ internationally advanced production lines
• Testing: 30+ sets of precision quality testing equipment
• Annual Output: Up to 50,000,000 tons
From Unprocessed Materials to Final Products
Our factory's fully automated production lines for cold heading, precision thread rolling, controlled-atmosphere heat treatment, and environmentally friendly surface finishing enable closed-loop manufacture from raw materials to finished goods. Because of inline optical sorting and a digital MES, each fastener meets stringent standards for strength, accuracy, and surface quality. You guarantee the best fasteners: dependable, efficient, and ecologically conscious.
Lab for Innovation:
Are you working on any projects right now? Let's proceed now. Our growth is fueled by talent and work, and we are always looking for new concepts. Are you engaged in a project? Let's proceed now.
"Pain Point Diagnosis" to "Customized Implementation" in the Entire Joint R&D Process
We provide more than just traditional parts. From the beginning of your project, our multicultural engineering team actively collaborates. We comprehensively study the application context and customize solutions in the lab, fully combining technology and application, to guarantee that innovative ideas are quickly transformed into practical solutions that lower overall lifecycle costs.
Integrated Verification System: Using "Test Data" to Assure Innovation
The creative process doesn't finish at the drawing board. We offer one-stop verification for everything from corrosion testing to prototype development through our internal technical center. We employ empirical data to verify the performance stability of customized solutions through comprehensive simulated working condition tests. In addition to achieving genuinely dependable cost reduction and efficiency improvement, this considerably lowers project risks.
