Nylon Insert Lock Nuts (commonly known as Nylock Nuts) represent a pinnacle of cost-effective anti-loosening technology. Unlike standard hex nuts that rely strictly on joint pre-tension and friction between metal mating threads, Nylock nuts integrate a non-threaded nylon collar situated in an extra cavity at the nut's exit.
Upon installation, mating bolt threads force their way through the undersized nylon collar. This causes elastic deformation of the polymer rather than thread-cutting, generating a continuous radial compressive force.
The friction created by this interference fit constitutes the "prevailing torque." It maintains lock integrity even under zero-pre-load or when joint relaxation occurs under constant thermal expansion cycles.
By conforming completely around the mating threads, the high-density nylon collar serves as a partial barrier, preventing moisture, corrosives, and particulate matter from infiltrating the thread interface.
In high-frequency vibration environments (e.g., dynamic machinery, vehicle chassis, industrial blowers), standard locking mechanisms like split lock washers or double nuts fail over time. Washers fatigue and flatten out, whereas Nylock nuts sustain their locking force over hundreds of load cycles. By customizing the formulation of our high-strength nylon inserts (Nylon 66 or specialized glass-filled nylon), Sinsun Hardware's ODM division ensures that prevailing torque specifications match the operational thermal bounds of your end application.
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.
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 expanded our facility into a 12,000-square-meter warehouse (including 1,200㎡ of instant stock). 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.
Sinsun Hardware manufactures Nylock Nuts conforming to international standards including DIN 985, DIN 982, ISO 7040, and ASME B18.16.6. Explore our typical production spectrum below.
| Specification Parameter | Carbon Steel (Medium/High Carbon) | Stainless Steel (Austenitic/Martensitic) | Alloy Steel / Specialized Alloys |
|---|---|---|---|
| Standard Conformity | DIN 985 / ISO 7040 / ASME B18.16.6 | DIN 985 / DIN 982 / ISO 10511 | ASTM A563 / ISO 7042 (All-Metal counterparts) |
| Metric Thread Range | M3 to M48 (Coarse, Fine, and Extra-Fine pitch) | M3 to M36 (Standard coarse & fine pitch) | M6 to M64 (Custom large diameters) |
| Imperial Thread Range | #4-40 UNC up to 2-1/2" UNF | #4-40 UNC up to 1-1/2" UNF | #10-24 UNC up to 3" UNF |
| Strength / Property Class | Class 5, Class 6, Class 8, Class 10, Class 12 | A2-70, A4-80, Duplex 2205 | ASTM A194 Grade 2H / 7 / 8M |
| Collar Material Options | Nylon 6 / Nylon 66 / Glass-Filled Nylon | Nylon 66 / High-Temperature PEEK (Custom) | Nylon 66 / Extreme-temp Elastomers |
| Surface Finishes | Zinc (Clear/Yellow), Zinc Flake (Geomet), Hot Dip Galv | Plain (Passivated), PTFE Coating, Electropolished | Cadmium, Black Oxide, Xylan Protective Coating |
Our ODM Nylon Insert Lock Nuts are engineered for critical applications around the world. Every industry demands unique performance profiles, which we deliver through precision engineering.
Underbody vehicle assemblies, engine mounts, and suspension linkage systems face relentless dynamic vibrations and high road debris exposure. We engineer Class 10 carbon steel Nylock nuts with Geomet coating to prevent hydrogen embrittlement and resist over 1,000 hours of salt spray exposure in winter climates.
Solar farm torque tubes in desert environments (e.g., Middle East, Western US) experience extreme thermal cycling (-10°C at night to 50°C midday) alongside intense UV exposure. Our custom-stabilized Nylon 66 inserts prevent UV degradation and maintain locking torque despite thermal dimensional changes.
Vibratory screens, rock crushers, and tractor attachments operate under constant shock loading. Our high-torque nylon inserts guarantee that fasteners do not spin off, avoiding catastrophic machine damage and saving operators thousands of dollars in unplanned downtime.
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.
Combined with German-engineered multi-station cold heading machines and precision Taiwanese production technology, we maintain strict control over every critical tolerance. Our specialized processes, including tail-gripping for drill screws and automatic locking collar injection for Nylock nuts, ensure every fastener is manufactured with utmost accuracy in our state-of-the-art 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.
As fastener technologies evolve to meet more demanding environmental regulations and extreme operating conditions, Sinsun Hardware's R&D department continues to lead with the following advancements:
Transitioning from petroleum-derived nylon to bio-based and highly stable polymers such as PEEK and carbon-fiber filled composites. This will push the thermal ceiling of Nylock nuts past 220°C, bridging the gap between nylon inserts and expensive all-metal prevailing torque nuts.
Integrating 360-degree high-speed camera optical sorting systems post-assembly. This process ensures that 100% of exported fasteners are checked for collar placement, concentricity, and micro-cracking, targetting a process defect rate of under 10 PPM (parts per million).
Phasing out older chemical coatings in favor of chromium-free zinc-flake and water-based inorganic protective coatings, ensuring complete compliance with the latest global RoHS 3.0 and REACH environmental guidelines.
Our commitment to E-E-A-T (Experience, Expertise, Authoritativeness, Trustworthiness) is backed by rigorous test environments. All Sinsun fasteners are subject to the following testing workflow before shipment:
Verifying chemical composition (C, Si, Mn, P, S, Cr, Ni) of incoming wire coils to prevent material mixing.
Utilizing Rockwell and Vickers hardness testers to confirm heat treatment uniformity across batches.
Accelerated corrosion chambers checking resistance up to 1,000+ hours as per ASTM B117 standards.
Applying prevailing torque and break-away torque tests to verify the integrity of the nylon collar fit.
