Product Overview
The graphite locking nut is a specialized fastener made from high-purity graphite material, specifically designed for high-temperature, vacuum, and corrosive environments. Combining graphite's heat resistance with self-lubricating properties, it solves common issues of traditional metal nuts such as oxidation-induced seizing and thermal expansion mismatch in extreme conditions. It is the ideal choice for semiconductor equipment, vacuum furnaces, and chemical pipelines.
Key Features
✅ Ultra-High Temperature Resistance
Stable operation up to 2200°C in inert environments, 800°C in oxidizing conditions (with coating)
✅ Self-Lubricating & Anti-Galling
Friction coefficient ≤0.15, preventing thread seizure at high temperatures
✅ Zero Thermal Expansion Mismatch
Thermal expansion coefficient only 1/10 that of metal, maintaining constant preload
✅ Chemical Corrosion Resistance
Withstands acids, alkalis, molten salts, and organic solvents
✅ Lightweight Design
60% lighter than metal nuts, reducing inertia in moving parts
Technical Specifications
|
Parameter |
Standard Type |
Enhanced Type |
|
Material |
Isostatic Graphite |
Carbon Fiber Reinforced Graphite |
|
Max Operating Temp |
2200°C (Inert) |
2400°C (Inert) |
|
Thread Size |
M4-M48 |
M3-M60 |
|
Tensile Strength |
25MPa |
90MPa |
|
Surface Treatment |
Uncoated/SiC Coated |
Multi-Layer Composite Coating |
|
Compatible Media |
Vacuum/Inert Gas |
Strong Acid/Molten Salt |
Typical Applications
1,Semiconductor Equipment
Wafer transfer robot fasteners, CVD reaction chamber sealing
2,Vacuum Heat Treatment
High-temperature furnace viewport locking, heating electrode fixation
3,New Energy Equipment
Fuel cell bipolar plate connections, electrolyzer assembly
4,Special Chemical Processing
Corrosive pipeline flange connections, molten salt pump fastening
Customization Services
Non-Standard Threads: Supports special thread types (e.g., UNC, UNF)
Composite Structures: Graphite-metal insert hybrid designs
Smart Monitoring: Integrated temperature/stress-sensing nuts
Fast Delivery: Small-batch orders completed within 10 business days
Quality Control
✔ Raw Material Testing: Ash content ≤100ppm
✔ Machining Precision: Thread pitch diameter tolerance ±0.01mm
✔ Performance Testing:
2000°C thermal shock cycling (20 cycles without cracking)
Salt spray test (500 hours without corrosion)
Usage Guidelines
⚠ Installation requires dedicated graphite tools (metal tools prohibited)
⚠ Initial tightening must be followed by secondary tightening at operating temperature
⚠ Coating integrity must be inspected every 500 hours in oxidizing environments
Selection Support: Provide operating conditions (temperature/media/vibration) for optimal model recommendations
(Related products: Graphite washers, graphite threaded sleeves)