Product Parameter Specifications
Parameter | Details |
Product Name | ISO 8765 Fine Thread Partial-Thread Hex Head Bolt |
Executive Standard | ISO 8765:2022, Grade A/B |
Replaced Standard | DIN 960 Fine Thread Half Thread Hex Bolt |
Accuracy Grade | Grade A (Precision), Grade B (General) |
Strength Grade | 8.8/10.9/12.9 High-strength Alloy Steel |
Size Range | M8-M36 Full Fine Thread Sizes In Stock |
Length Range | 20mm-300mm Standard Length, Custom Length Available |
Structure | Hex head, smooth shank, partial fine thread design |
Surface Finish | Black Oxide, Zinc Plated, Hot-dip Galvanized, Phosphating |
Material | High-quality Quenched & Tempered Alloy Steel |
Core Features | Fine thread self-locking, precise adjustment, anti-vibration, shear resistance, heavy load stability |
Application | Hydraulic equipment, precision machinery, heavy-duty equipment, vibrating devices, jigs & fixtures |
Quality Control | Dimension, thread gauge, hardness, tensile strength and concentricity full inspection |
Package | Export carton + pallet, neutral packaging available |
Supply Capacity | Mass stock, bulk orders and non-standard customization supported |
Core Product Advantages
The fine pitch thread design reduces thread lift angle and enhances meshing tightness, providing superior self-locking ability compared with standard coarse threads. It effectively prevents loosening under high-frequency vibration and alternating load conditions, ensuring long-term stable fastening without extra anti-loosening accessories.
Smooth Shank for High Shear Resistance & Positioning Accuracy
The solid smooth shank improves structural rigidity and concentricity, capable of bearing lateral shear force. It ensures precise hole positioning and zero assembly deviation, ideal for precision docking and heavy-load structural connection scenarios.
Fine thread provides smaller feed per rotation, allowing accurate preload adjustment. It avoids workpiece deformation and thread damage caused by excessive torque of coarse thread bolts, perfectly suitable for precision hydraulic components and thin-wall heavy-load parts assembly.
Complete High-strength Grades for Heavy-duty Scenarios
Manufactured with 8.8 to 12.9 grade quenched and tempered alloy steel, featuring high tensile strength, good toughness and excellent fatigue resistance. It stably bears long-term static heavy load and dynamic alternating load for engineering and hydraulic heavy-duty equipment.
Dual A/B Precision Grades
Grade A for high-precision equipment replacement and precision mold assembly; Grade B for cost-effective mass heavy-duty production. Dual-grade design meets diverse precision and budget requirements of global industrial projects.
ISO8765 Fine Thread VS ISO4014 Coarse Thread Selection Guide
ISO8765 Fine Thread Partial Thread Bolt: Fine pitch, strong self-locking, high adjustment accuracy and outstanding anti-vibration performance. Preferred for precision heavy-duty, high-vibration and precise preload scenarios such as hydraulic systems and precision machine tools.
ISO4014 Coarse Thread Partial Thread Bolt: Large pitch, fast assembly and high versatility. Suitable for general machinery, steel structures and conventional fastening with low precision and anti-vibration requirements.
Production Process
Raw Material Selection: High-standard alloy steel with stable composition for high-strength heat treatment.
Cold Heading Forming: Standard hex head and straight shank with precise dimensions.
Professional Fine Thread Rolling: Dedicated fine thread rolling process ensures full tooth profile and 100% gauge qualified.
Quenching & Tempering: Overall heat treatment to balance hardness and toughness for heavy-load resistance.
Surface Anti-corrosion Treatment: Black oxide, zinc plating, hot-dip galvanizing and phosphating as required.
Precision Full Inspection: Strict inspection on thread precision, dimension, hardness and mechanical properties.
Application Industries
Hydraulic Industry: Precision locking of hydraulic valve groups, pipelines and cylinder components.
Precision Machine Tools: High-precision assembly of machine frames, guide rails and tooling fixtures.
Heavy-duty Engineering Machinery: Fastening and positioning of vibrating and heavy-load joints.
Automation Heavy Equipment: Structural connection for high-frequency operating devices.
High-end Precision Supporting Projects: Imported equipment replacement and precision industrial assembly.
Why Choose Our ISO8765 Bolts
We specialize in manufacturing ISO8765 Grade A/B fine thread partial-thread hex bolts in full compliance with ISO 8765:2022 standards. Complete fine thread sizes and high-strength grades are in stock. We provide material certificates, mechanical test reports, sample support, bulk export and non-standard fine thread customization, delivering reliable high-precision heavy-load fastening solutions.
Installation & Usage Notes
1. Professional Selection: Choose ISO8765 fine thread for precision vibration and heavy-load adjustment scenarios; select ISO4014 coarse thread for general assembly to avoid performance mismatch.
2. Matched Accessories: Fine thread bolts must be matched with corresponding fine thread nuts. Never mix coarse and fine thread to prevent thread damage.
3. Standard Torque Operation: Tighten slowly with standard torque. Avoid over-tightening to protect dense fine thread profile.
4. Anti-vibration Priority: Fine thread self-locking structure is preferred for continuously vibrating and alternating load equipment for higher stability.
5. Prohibit Reuse: 10.9/12.9 high-strength structural bolts shall not be reused after bearing preload to eliminate fatigue failure risks.
For ISO8765 fine thread bolts, full range of ISO standard fasteners and customized fastening solutions, please contact us for professional technical support and accurate quotation.
