High-Tensile Hex Screw for Hydraulic Rock Drills This hex screw is engineered to secure critical components in hydraulic rock drills, withstanding vibration, axial loads, and abrasive mining environments. Constructed from 8.8 级 high-tensile steel（ISO 898-1）, it delivers reliable clamping force in high-stress applications such as securing drill housings, valve bodies, and hydraulic fittings.
Key Performance Attributes
Material & Durability:
8.8 级 high-tensile steel achieves 800MPa tensile strength, providing a 20kN clamping load—suitable for heavy-duty fastening in hydraulic rock drills. The zinc plating（8μm, ASTM B633） offers 72-hour salt spray resistance（ASTM B117）, preventing corrosion in damp underground mines .
Precision Engineering:
M12x30mm thread（ISO 4017） with 6g thread tolerance ensures compatible mating with standard nuts and tapped holes. The h6 shaft tolerance（ISO 4759-1） guarantees proper fit in precision-machined components, reducing vibration-induced loosening .
Hexagonal head（19mm 扳手 size） facilitates secure torque application, while the integrated thread locker patch maintains clamping force in high-vibration environments.
Operational Reliability:
Operating temperature range（-40°C to +120°C） ensures performance stability in extreme mining conditions, from cold underground tunnels to high-friction mechanical systems. The screw’s design meets ISO 4017 standards, ensuring interchangeability with OEM components .
Applications
Hydraulic Rock Drills: Secures housings, cylinder mounts, and valve assemblies in R38 models.
Mining Equipment: Compatible with tunneling machines, quarry drills, and mineral exploration rigs.
Industrial Machinery: Suitable for heavy-duty fastening in hydraulic systems, conveyor frames, and industrial presses.
