Release time：2020-01-16 18:44 Browse：
### 1. **Manufacturer Focus & Compliance** - Specializes in manufacturing **lengthening screws/bolts** that strictly comply with **GB5789** (China’s national standard for hexagonal flange bolts), ensuring uniformity in flange dimensions, thread specifications, and head design. - Core product: Hexagonal flange galvanized lengthening bolts with a semi-threaded structure, tailored for applications requiring extended reach. ### 2. **Product Design & Structural Details** - **Lengthened Shank**: Longer overall length than standard bolts (customizable per project needs), enabling fastening of thick materials, multi-layer assemblies, or deep-set components (e.g., heavy machinery frames, structural brackets). - **Semi-Threaded Configuration**: Features a threaded section (for secure engagement with nuts/threads) and a smooth, unthreaded shank (reducing material waste and allowing flexibility in alignment during installation). - **Hexagonal Flange Head**: Integral hexagonal drive (compatible with standard hex wrenches/sockets) paired with a circular flange. The flange acts as a built-in washer, distributing clamping force to prevent workpiece damage (e.g., wood, plastic, or thin metal) and enhancing stability under vibration. ### 3. **Surface Treatment: Galvanization** - **Zinc Plating Process**: Electroplated zinc coating (typically 8-25μm thick) applied to the bolt surface, forming a protective barrier against oxidation and rust. - **Additional Protection**: May include a passivation layer (e.g., chromate treatment) to improve zinc adhesion, extend corrosion resistance, and ensure a uniform, bright finish—suitable for indoor, dry, or moderately humid industrial environments. ### 4. **Materials & Mechanical Performance** - Crafted from high-quality carbon steel or alloy steel (e.g., 45# steel, 10B21, or 35K), selected for strength and machinability. - Heat-treated (quenched and tempered) to meet common strength grades (e.g., 8.8 grade: tensile strength ≥800MPa, yield strength ≥640MPa), ensuring durability under static or dynamic loads. - Semi-threaded design balances threading length (for secure grip) and unthreaded shank (for adaptability to uneven or thick workpieces). ### 5. **Key Advantages** - **Extended Reach**: Lengthened shank eliminates the need for spacer washers or custom fabrication when fastening thick/stacked components. - **Flange Benefits**: Integral flange reduces assembly time by replacing separate washers, while its large contact area minimizes pull-through in soft materials. - **Corrosion Resistance**: Galvanized coating protects against rust in non-extreme environments (e.g., factory floors, indoor machinery), extending service life. - **Versatile Semi-Threading**: Allows partial insertion into pre-drilled holes without binding, ideal for aligning misaligned or variable-thickness parts. ### 6. **Applications Across Industries** - **Heavy Machinery**: Securing large brackets, engine blocks, or conveyor system components where extended length is needed to reach through thick metal plates. - **Construction**: Fastening structural steel, precast concrete panels, or outdoor fixtures (e.g., streetlight poles) where galvanized protection and long shanks prevent loosening. - **Automotive & Transportation**: Assembling truck chassis, trailer frames, or vehicle undercarriage parts, where vibration resistance and extended grip are critical. - **Industrial Equipment**: Fixing control panels, machine guards, or hydraulic system components in factories, leveraging the semi-threaded design for easy adjustment. ### 7. **Manufacturing & Quality Control** - Offers customizable lengths (beyond standard sizes) while maintaining GB5789 compliance, catering to unique project specifications. - Implements strict quality checks: dimensional verification (thread pitch, flange diameter, shank length), galvanization thickness testing (via micrometers), and mechanical performance trials (tensile, torque, and corrosion resistance). - Ensures consistent plating coverage (no bare spots or uneven zinc layers) and precise threading to avoid cross-threading during installation. ### 8. **Customer Support & Capabilities** - Provides technical documentation (material certificates, GB5789 compliance reports) and guidance on bolt selection (e.g., matching length to workpiece thickness). - Accommodates bulk orders for industrial projects, with options for custom packaging (e.g., boxed, palletized) to streamline logistics.
