Industrial-grade nails, staples, rivets, and customized structural screws engineered to global standard compliances.
Stainless steel cap nuts, also known as dome nuts or acorn nuts, perform a critical dual role: safeguarding underlying thread projections from environmental aggression (moisture, acidic fumes, and physical shear) and preventing mechanical abrasion against adjacent components. The internal thread cavity depth is precisely engineered to avoid bottoming out, ensuring maximum preload retention.
Utilizing premium SS304 (A2) and SS316 (A4) raw materials, our cap nuts achieve excellent resistance to chloride-induced stress corrosion cracking. SS316, enhanced with 2-3% Molybdenum, serves as the industrial standard for marine settings and chemical process piping, maintaining its yield strength under extreme thermal and mechanical loads.
Our OEM output adheres to stringent global standards including DIN 1587 (high-type dome nuts), DIN 917 (low-type dome nuts), and ASME B18.2.2. Utilizing multi-station cold heading alongside high-speed CNC finish operations guarantees concentricity tolerances down to ±0.02mm, providing precise thread fitment.
Established in 2006, Sinsun Hardware is a leading manufacturer and global supplier of high-quality fasteners. We operate from a gigantic 30,000 sqm integrated facility that includes modern production zones, a 12,000 sqm smart warehouse (with an 18,000+ pallet capacity), and multi-language customer support centers. 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 tensile strength (1,000+ MPa), and consistent hardness (HRC 28-32).
We specialize in offering unique fastening solutions tailored to your specific project needs. Our technical team works directly with clients from design to manufacturing, providing OEM support for unusual materials, custom coatings, non-standard dimensions, and rigorous performance requirements.
Developing high-strength, anti-galling coatings and smart-manufacturing infrastructure to address the next generation of industrial fastening challenges.
Stainless steel threads are inherently susceptible to galling under torque. Our R&D is focused on applying micro-thin dry-film lubricants directly to internal cap nut threads to ensure uniform friction coefficients without wet grease contamination.
Transitioning to zero-defect criteria (0 PPM) across large production runs, Sinsun is deploying intelligent optical sorting machines utilizing machine vision to flag micro-cracks and thread deviations undetectable by mechanical gauges.
In response to expanding chemical processing requirements, we are expanding our custom cap nut material range to include Duplex SAF 2205 and Super Duplex alloys, doubling the tensile performance of standard A4 steel.
Aligning with global decarbonization frameworks, our 2026 roadmap implements certified low-emission steel wire rods and recuperative gas-fired furnaces to minimize our carbon footprint per ton of finished fasteners.
Tailoring dimensional standards and structural integrity to demanding operating environments globally.
Exposed to constant spray and salt atmospheres, standard components suffer rapid pitting. Sinsun's SS316 cap nuts provide high pitting resistance (PREN ≥ 23), offering robust performance in structural yacht building and offshore drilling platforms.
Refineries operate under thermal fluctuations and corrosive gases. Cap nuts seal thread extensions, preventing gas leaks from deteriorating structural joints and assuring pressure vessel enclosure integrity over long inspection cycles.
Continuous vibrations pose a fatigue risk. Through strict HRC 28-32 tempering control and precise thread profiling, our cap nuts achieve excellent resistance to thread loosening and backing off under dynamic loads.
A chronological view of our capacity expansion, manufacturing modernization, and global alignment since 2006.
Sinsun was founded with a primary specialization in high-volume self-tapping screws, establishing our core expertise from the ground up.
Established the specialized Export Department to distribute high-grade structural fasteners to industrial partners worldwide.
Added four spheroidizing annealing furnaces and in-house wire drawing capabilities to achieve absolute quality control starting from wire rod materials.
Imported advanced German multi-station cold heading machines to expand technical capabilities for self-drilling, cap, and custom structural fasteners.
Reached 36,000 tons in annual output and surpassed 1,100 export containers shipped worldwide in a single fiscal year.
Opened our 1,200 sqm ready-stock facility within our larger 12,000 sqm smart warehouse to facilitate rapid dispatch of standardized lines.
Integrated 4 state-of-the-art continuous heat treatment lines to assure mechanical strength and structural consistency.
In the current global economic landscape, reliability is as crucial as technical quality. Sinsun's operations utilize the core principles of China Factory 4.0 to mitigate supply disruptions. By maintaining direct integration with Xingtai Steel, we secure a stable supply of premium carbon and alloy wire rods, protecting clients from raw material market fluctuations.
Inside the factory, digitized production lines monitor execution parameters in real-time. From annealing temperature profiles to cold-heading forging pressures, every variable is tracked. This level of quality management allows us to maintain a low scrap rate and consistently deliver standard-compliant fasteners on time.
Internal gas-fired spheroidization furnaces prepare structural steels for dynamic cold heading without cracking risks.
Advanced chemical passivation lines strip free iron from stainless steel surfaces, creating a corrosion-resistant oxide layer.
Our 12,000 sqm warehouse features automated racking that interfaces with customer ERP structures to enable smooth logistics dispatch.
We align our manufacturing with the compliance protocols, shipping demands, and quality validation processes of multi-national procurement organizations.
Every shipment is backed by comprehensive MTRs (Material Test Reports) detailing chemical ladle analysis, hardness parameters, and torque testing. We provide EN 10204 3.1 certification upon request to verify international compliance.
Our 12,000 sqm logistics facility supports customized labeling, retail display cartoning, bulk crate packaging, and robust palletizing configurations. We apply multi-standard barcoding to help streamline customer inventory operations.
Sinsun helps buyers navigate complex regional import policies, environmental restrictions (RoHS and REACH compliance), and duty rates, providing a reliable and compliant import process.
Technical and logistical details regarding custom OEM cap nuts, manufacturing capabilities, and standard requirements.
Thread galling typically occurs when pressure and friction cause the oxide layer of stainless steel surfaces to rub off, resulting in localized welding. We address this by maintaining precise thread tolerances (±0.02mm) and offering anti-galling wax coatings or thin-film dry lubricants to reduce installation friction.
We manufacture in strict compliance with DIN 1587 (hexagonal domed cap nuts, high type), DIN 917 (hexagonal cap nuts, low type), and ASME B18.2.2 (acorn and cap nuts). Custom OEM dimensions can also be produced based on customer-supplied blueprints.
SS304 (A2) contains chromium and nickel, providing good corrosion resistance for general applications. SS316 (A4) includes 2-3% Molybdenum, which increases its resistance to pitting and crevice corrosion in chloride-rich environments like marine installations and chemical processing systems.
Yes, we carry out regular salt spray testing in accordance with ASTM B117 standards. Depending on the steel grade and surface passivation treatments applied, our products are engineered to withstand over 1,000 hours of continuous exposure without showing signs of red rust.
For standard sizes and grades, we offer low MOQ requirements, especially when utilizing our 1,200 sqm ready stock. For non-standard custom dimensions requiring tooling adjustment, the MOQ typically ranges from 50,000 to 100,000 pieces depending on material size and manufacturing steps.
Yes, we offer complete quality traceability starting from XING TAI Steel raw materials. We provide mechanical test reports, chemical analysis certificates, and EN 10204 3.1 mill certs with each shipment.
We regularly host international clients at our 30,000 sqm production site, showing our commitment to manufacturing transparency and global standard compliance.
Our comprehensive structural fastening collection designed for building, masonry, roofing, and heavy-duty structural applications.
Sinsun's engineering team provides detailed 3D designs, CAD drawings, and prototype validation services for custom OEM stainless steel cap nuts. Partner with a supplier equipped with German cold heading technology, internal heat treatment lines, and a 12,000 sqm logistics center.
