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Core Specification Parameters: Key Basis for Selection

Size Specifications

• Thread diameter: Common ranges are M2-M12, adapted to different load requirements. For example, M2-M4 is commonly used in electronic equipment, while M8-M12 is optional for heavy machinery.
• Screw length: Excluding the head, the length ranges from 3mm to 50mm. It should be selected based on the thickness of the connected component, usually 2-3mm longer than the total thickness of the connected component to ensure complete thread engagement.
• Head size: The head diameter and height comply with industry standards. For instance, an M3 screw has a cap head diameter of approximately 5.5mm and a height of 3mm, while an M5 screw has a cap head diameter of about 8.5mm and a height of 5mm—these dimensions ensure compatibility with tools.

Precision Grade

• Thread precision: Mostly 6g (external thread), compatible with H7 (internal thread) connectors to ensure uniform thread fit clearance, avoiding loosening or jamming.
• Hexagon socket precision on the head: Reaches H13, with smooth groove walls and no burrs. It is compatible with hexagon wrenches of corresponding specifications (e.g., an M3 screw matches a 2mm hexagon wrench, and an M5 screw matches a 3mm hexagon wrench), reducing the risk of tooth slipping during driving.

Performance Specifications

• Temperature resistance: Continuous service temperature ≥260℃, short-term temperature resistance up to 300℃.
• Mechanical strength: Tensile strength ≥90MPa, elongation at break ≥15%, ensuring no deformation in extreme environments.
• Corrosion resistance: Passes a 48-hour neutral salt spray test without corrosion; no cracking when immersed in organic solvents (e.g., ethanol, acetone), making it suitable for scenarios such as medical disinfection and chemical contact.

Usage Guide: Comprehensive Key Points from Installation to Maintenance

1. Pre-Installation Preparation: Model Selection & Tool Compatibility

• Medical equipment (e.g., surgical instruments): Prioritize small-size screws (M2-M4, length 5-15mm) to ensure lightweight and biocompatibility.
• Aerospace components (e.g., sensor fixation): Medium-size screws (M5-M8, length 10-30mm) are optional, balancing strength and temperature resistance.
• Chemical equipment (e.g., pipeline joints): Large-size screws (M8-M12, length 20-50mm) are required to enhance corrosion resistance and load-bearing capacity.

• Use high-hardness chrome-vanadium steel hexagon wrenches to avoid damage to the hexagon socket caused by wrench wear.
• For automated assembly, match torque-controllable electric screwdrivers and preset torque values (usually 0.8-1.2N・m for M3 screws and 2.5-3.5N・m for M5 screws) to prevent over-tightening or under-tightening.

2. Installation Steps: Ensure Precision & Safety

• Pretreatment: Clean the threaded holes of the connected components and the screw surface to remove oil and impurities. For medical scenarios, sterilize with high-temperature steam (121℃) for 15 minutes to avoid contamination. If the connected component is made of metal, apply a small amount of PEEK-specific anti-seize agent (e.g., PTFE-based lubricant) to the screw thread to reduce friction and wear between metal and PEEK.
• Screwing operation: Manually align the screw with the threaded hole and gently turn it clockwise 2-3 turns to confirm no thread misalignment. Then use a hexagon wrench or electric tool to screw it in at a constant speed, with the rotation speed controlled at 10-20r/min (to avoid high temperatures from high-speed rotation causing PEEK softening). Stop screwing when the head fits the surface of the connected component—do not apply excessive force to prevent head cracking or thread slipping.
• Inspection and acceptance: After installation, recheck the torque value with a torque wrench, ensuring the error is within ±10%. Check if the head fits flat without tilting or protruding. For medical equipment, additional leak tests (e.g., 0.3MPa air pressure test with no leakage) are required to ensure sealing performance.

3. Maintenance & Precautions: Extend Service Life

• Daily maintenance: Inspect the screw status regularly (every 3-6 months). For medical equipment, clean and disinfect after each use to avoid residual disinfectant corroding the material. For outdoor or high-temperature scenarios (e.g., aerospace equipment), disassemble and inspect annually—if thread wear or head deformation is found, replace with screws of the same specification in a timely manner.
• Forbidden scenarios: Avoid long-term use in environments exceeding 300℃ to prevent PEEK material degradation; do not use in strong acid (e.g., concentrated hydrochloric acid) or strong oxidizing (e.g., concentrated nitric acid) environments to avoid material corrosion; prohibit the use of ordinary carbon steel wrenches to prevent scratches on the hexagon socket, which may affect subsequent disassembly.

Adaptation Scenarios: Utilize Material & Structural Advantages

• Medical equipment: Small-size M2-M3 screws are used for fixing endoscope lenses, featuring disinfection resistance and non-magnetism.
• New energy vehicle battery packs: M4-M6 screws fix battery cell brackets, with electrolyte corrosion resistance and lightweight properties.
• Semiconductor manufacturing equipment: M3-M5 screws fix wafer stages, with low volatility to avoid wafer contamination.