Product Parameter Specifications
Parameter | Details |
Product Name | ISO 7042 All‑Metal Prevailing Torque Nut |
Standard | ISO 7042‑2025 |
Thread Size | M12‑M39, sizes in brackets are non‑preferred |
Strength Class | 8,10,12 |
Locking Type | All‑metal deformed prevailing torque, no nylon insert, locking profile optional |
Material | Carbon steel, alloy steel |
Surface Finish | Black oxide, zinc plated, hot‑dip galvanized, zinc‑nickel |
Key Features | High‑temperature resistant, anti‑vibration, fully‑metal, reusable |
Applications | Vibration & high‑temp condition, construction machinery, engine components |
Quality Inspection | Dimension check, thread gauge, prevailing torque test, hardness, visual inspection |
Supply Capacity | Stock for regular sizes, bulk export orders available, test reports on request |
Core Product Advantages
Without nylon insert, no risk of nylon melting or aging under heat. Suitable for working temperatures where nylon lock nuts cannot perform.
Controlled metal deformation generates prevailing torque, increases thread friction and reduces risk of self‑loosening under continuous vibration.
Standard hex profile for good compatibility
Standard hexagon body works with common hex nut tools. Locking end profile can be selected as per customer requirement.
High strength grades for heavy‑duty bolting
Available in class 8‑12 to match high‑strength bolts for heavy‑load mechanical connections.
Production Process
Raw Material Preparation Qualified carbon/alloy steel bar stock for stable mechanical performance.
Cold Heading Multi‑station cold forging forms hex body, critical dimensions comply with ISO7042 drawing.
Tapping CNC tapping, thread pass‑fail gauge inspection to guarantee smooth mating.
Prevailing Torque Deformation Controlled squeezing operation to form the locking torque section.
Heat Treatment Quenched and tempered to reach required hardness and toughness for each strength class.
Surface Treatment Black oxide, electro‑plating, zinc‑nickel for corrosion resistance.
Inspection & Sorting Dimensional, thread, torque and hardness test, reject defective parts.
Application Industries
Construction Machinery Anti‑loosening joints for excavators, loaders and vibrating assemblies.
Engine & Power Equipment Fastening for engine surrounding parts under heat and vibration.
Heavy‑duty Transmission Gearboxes, drive shafts, vibrating mechanical assemblies.
Industrial High‑temp Equipment Machine base and frame connections under elevated temperature.
Installation & Usage Notes
1. Matching bolt grade Use nuts with corresponding strength‑grade bolts; avoid pairing with low‑strength bolts.
2. Correct tightening torque Follow recommended torque values for each thread size, over‑torque may damage threads.
3. Re‑use limitation Prevailing‑torque value will drop after multiple disassembly. Replace nuts for safety‑critical joints.
4. Clean thread surface Keep threads free of chips and dirt to maintain stable locking torque.
Why Choose Our ISO7042 Lock Nuts
NINGBO TOPBOLT METALWORKS CO., LTD supplies ISO7042 all‑metal prevailing torque nuts manufactured strictly against ISO7042‑2025 drawing specifications. Stable prevailing‑torque performance and tight dimensional control. Regular sizes in stock for bulk export orders, test documentation available for machinery & engine‑industry customers.
Get quotation and technical support for ISO7042 all‑metal lock nuts, contact our sales team.
