Explore our precision-engineered selection of B2B industrial fasteners, anchor elements, and custom hardware components manufactured for durability.
Serrated washers (also referred to as serrated lock washers or star washers) represent a critical engineering solution for managing vibration-induced loosening in threaded fastners. As global manufacturing demands rise, particularly in automotive, aerospace, structural engineering, and solar energy systems, standard flat washers are no longer sufficient to guarantee joint integrity under dynamic mechanical stresses.
The operational mechanics of a serrated washer depend on the localized biting action of its teeth. When compressed under preload, these teeth dig into the mating surface of the nut or bolt head and the parent material. This dynamic friction prevents counter-rotational movement. Depending on the loading pattern, engineers can choose between Internal Serrated Washers (DIN 6798 Type J), which provide flush contact for smaller fastener heads, and External Serrated Washers (DIN 6798 Type A), which optimize torque resistance by placing the locking diameter at the outer perimeter.
For custom ODM configurations, selecting the correct material, tooth deflection angle, and surface treatment is paramount. Sinsun Hardware matches these parameters with ISO/EN standards to supply robust anti-vibration systems that extend product lifecycles in critical operating environments.
Sinsun Hardware, established in 2006, is a leading manufacturer and global supplier of high-quality fasteners. As Northern China's largest producer of Self-Tapping Screws, we operate from a gigantic 30,000 sqm integrated facility that includes modern production zones, a 12,000 sqm smart warehouse (18,000+ pallet capacity), and multi-language customer support centres. Our yearly supply of over 8,500 containers consistently services key global markets such as the Middle East, Southeast Asia, South America, and Russia.
Our production prowess is driven by German-imported machinery, precision Taiwanese technology, and a dependable staff of trained specialists. We offer over 20,000 SKUs of nails, screws, wires, and rivets, each undergoing 12+ stringent quality checks to assure outstanding polish (Ra ≤ 0.4μm), corrosion resistance (1,000+ hours salt spray), dimensional accuracy (±0.02mm), high strength (1,000+ MPa), and consistent hardness (HRC 28-32).
We specialise in offering unique fastening solutions that are tailored to your specific needs. Our technical team works directly with clients from design to manufacturing, providing support for unusual materials, coatings, dimensions, and performance requirements to ensure that each custom order matches exact specifications.
We guarantee reliable and rapid lead times for both standard and special orders by using our integrated facility, optimised inventory, and effective planning. Sinsun Hardware is your strategic partner, committed to delivering quality, innovation, and on-time performance worldwide.
Choose the optimal parameters for your specific high-torque, anti-vibration applications. Our OEM/ODM tooling services allow customization across international sizing frameworks.
| Specification Parameter | DIN Standard Equivalents | Available Materials | Surface Treatment Options |
|---|---|---|---|
| External Teeth (Type A) | DIN 6798-A / ISO 7273 | Carbon Steel, SS304, SS316, A4-80 | Yellow Zinc, Dacromet, Geomet 500 hours |
| Internal Teeth (Type J) | DIN 6798-J | Carbon Steel, SS304, SS316 | Passivated, Electro-galvanized, Phosphated |
| Countersunk Teeth (Type V) | DIN 6798-V | High-tensile Spring Steel, SS304 | Zinc Flake Coating, Plain Oil Finish |
| Custom Tooth Profiles | ODM Tailored Geometry | Alloy Steels, Carbon Steels, Cu/Ni Alloys | Nickel Plating, Multi-layer Epoxy, Salt-spray > 1000h |
From Sinsun founding in 2006, Sinsun has grown into a leading Chinese fastener manufacturer. Explore our journey of expansion, from establishing exports in 2012 and integrating German technology in 2018, to achieving a 36,000-ton annual output and adding advanced heat treatment lines by 2025.
Sinsun began with a singular focus in 2006: to build a factory dedicated to self-tapping screws. This foundational specialization established our core expertise from the ground up. It remains the unwavering commitment behind every screw we manufacture today.
The year 2012 marked a pivotal step for Sinsun with the establishment of our Export Department. From that point forward, our specialized self-tapping screws began reaching customers across the world, expanding our mission beyond borders.
In 2015, Sinsun expanded its control over quality by adding four spheroidizing furnaces for raw material processing and in-house wire drawing capabilities. This strategic upgrade moved our production beyond screw manufacturing, beginning with precise control from the raw material stage. It ensures superior consistency and performance in every piece screw we produce.
Our production capability was enhanced in 2018 with new German multi-station cold heading machines. Concurrently, we grew our product line to include a variety of drill tail screws. This dual development strengthened our specialized manufacturing foundation.
Sinsun's growth in 2021 was defined by two key metrics: reaching 36,000 tons in annual production and fulfilling international orders with over 1,100 export containers. This period underscored our capacity to deliver at scale to a global market.
To ensure timely delivery for our clients, we operate a 1,200-square-meter ready-stock warehouse as of 2023. This facility is dedicated to supporting efficient daily distribution and meeting your routine supply needs.
The addition of four heat treatment lines in 2025 significantly boosts our production capacity. This directly translates to greater consistency in product quality and stronger guarantees for on-schedule delivery, meeting your project needs with confidence.
At SINSUN, our quality control begins at the source. We start with premium raw materials from XING TAI Steel, then perform in-house spheroidizing annealing and precision wire drawing in our own plant. This end-to-end control, supported by our advanced drawing machines and gas-fired furnaces, ensures superior microstructure, consistency, and performance in every fastener we produce.
At SINSUN, we combine German-engineered multi-station cold heading machines with precision Taiwanese production technology. Our specialized processes, including tail-gripping for drill screws, ensure every fastener is manufactured with utmost accuracy and consistency in our state-of-the-art production facility.
SINSUN operates four dedicated heat treatment lines, allowing for precise and controlled processing time to achieve consistent hardness and enhanced product durability. This in-house capacity ensures both exceptional fastener quality and reliable delivery schedules. Our advanced heat treatment systems support our end-to-end manufacturing control.
Sourcing engineers face persistent issues with structural failures arising from bolt tension relaxation. For systems exposed to continuous thermal expansion cycles or mechanical shaking—such as automotive chassis, heavy industrial gearboxes, and solar rooftop racking arrays—serrated washers provide an essential locking mechanism.
Modern B2B purchasing processes prioritize supply chain traceability and material testing verification. High-strength applications typically require carbon spring steel with specific hardening treatment, while marine or chemical environments demand Grade 316 stainless steel with specialized passivation coatings. An ODM partner like Sinsun Hardware allows global procurement offices to customize dimensions, teeth depth, and zinc-nickel platings to match these dynamic environment-specific requirements.
SINSUN offers flexible OEM and ODM packaging tailored to your needs. With a professional packaging team and a 12,000 m² warehouse, we provide custom packaging, 3D design previews, and full logistics support to deliver a seamless, worry-free experience from production to shipment.
Our warehouse features automated inventory indexing to handle large-scale shipments. This infrastructure underpins our capacity to export over 8,500 containers yearly while maintaining stock for rapid standard order fulfillment.
Every month, we welcome clients from across the country and around the globe for on-site factory visits, demonstrating our transparency and production strength. As a trusted industry partner, we actively participate in global exhibitions to connect, exchange insights, and showcase innovation — building lasting relationships based on quality and reliability.
Get direct answers to common engineering questions regarding serrated washers selection, materials, and ODM customization capabilities.
Serrated lock washers provide superior locking action in high-vibration applications. While split washers rely solely on spring tension, serrated washers bite into both mating surfaces. This physical interference prevents loosening, making them ideal for applications prone to constant movement and thermal expansion.
Internal serrated washers (DIN 6798 J) feature teeth along the inner diameter, making them ideal for smaller bolt heads and applications requiring a clean, snag-free exterior profile. External serrated washers (DIN 6798 A) place the teeth along the outer perimeter, maximizing the locking radius and providing higher rotational resistance on larger fastener assemblies.
To minimize the risk of hydrogen embrittlement in high-strength carbon steel washers (especially those graded over 1000 MPa), we execute a strict baking process (typically at 200°C for 4 to 8 hours) immediately after acid pickling and electro-galvanizing. This ensures trapped hydrogen molecules diffuse out, preventing sudden brittle fractures under load.
We support complete customization. This includes custom dimensions (thickness, outer and inner diameters), specific tooth counts, exotic material compositions (such as premium spring steels or alloy grades), and specialized surface finishes (like Geomet, Dacromet, or multi-layer zinc platings) to match particular salt-spray and torque expectations.
The four newly added heat treatment lines allow precise, digitally monitored tempering and quenching phases. By controlling thermodynamic parameters, we achieve uniform microstructural transformation. This guarantees consistent hardness across production runs (HRC 28-32 for standard steel applications), minimizing variations in washer bite force.
Yes. All shipments can be accompanied by complete Quality Assurance documentation, including Material Test Reports (MTR) verifying chemical composition, Hardness Certificates (HRC/HV), Salt Spray Test logs (ISO 9227), and Dimensional Measurement logs indicating compliance with defined engineering tolerances.
Partner with China's premier fastener factory. Submit your dimensions, target standards, and volume requirements for a detailed quotation within 24 hours.
We provide an extensive catalog of industrial fixing, structural stabilization, and surface protection fasteners.
