Product Name
Loctite 271 High-Strength Threadlocker
Brief Description
Loctite 271 is a red, low viscosity, high-strength, anaerobic-curing adhesive designed for the permanent locking and sealing of threaded fasteners. It cures in the absence of air between close-fitting metal surfaces, effectively preventing loosening and leakage caused by severe shock and vibration. This product also offers protection against rust and corrosion for the threads.
Popular Applications & Uses
- Automotive: Ideal for internal engine components, auto frames, auto suspensions, wheel studs, valve covers, water pumps, and alternators.
- Industrial Maintenance: Used on heavy machinery, structural fasteners, heavy conveyors, and material movers.
- Construction & Home: Suitable for structural bolts in residential applications, handrails, play sets, and heavy-duty equipment.
- Heavy Equipment: Applied in truck and trailer assembly, including suspensions and drivetrain components.
- Machine Tooling: Secures high-torque bolts in lathes and mills.
- Energy Sector: Utilized for locking anchor bolts in wind power equipment, where dynamic stresses are common.
- General Assembly: Permanent locking and sealing of large bolts and studs up to M25 (1 inch) in diameter.
Industries that Commonly Use It
- Aerospace/Defense: Meets specifications like US Military MIL-S-46163 Notice 4 Type 1 Grade K and Pratt and Whitney CML 09-002F.
- Automotive Service/Repair: Essential for securing critical fasteners in engines, chassis, and other vehicle systems.
- Construction/ Building Services: Used for structural integrity in buildings and heavy-duty equipment.
- Energy: Critical for maintaining the integrity of components in power generation, such as wind turbines.
- General Manufacturing: Employed in the assembly of various machinery and equipment requiring robust fastener locking.
- Metal Fabrication: Utilized for securing metal components in fabricated structures and machinery.
- Transportation/ Specialty Vehicle: Applied in the assembly and maintenance of trucks, trailers, and other specialized vehicles.
Special and Unique Features
- High Strength: Provides a permanent lock for threaded fasteners.
- Anaerobic Cure: Cures in the absence of air when confined between close-fitting metal surfaces.
- Vibration and Shock Resistance: Prevents loosening and leakage from severe operational stresses.
- Corrosion Protection: Protects threads from rust and corrosion.
- Low Viscosity: Allows for easy application and penetration into threads.
- UV Fluorescent: Fluoresces under UV light, enabling easy quality control and inspection.
- Oil Tolerance: Can tolerate slight contaminations of industrial oils.
- Seals Threads: Effectively seals threads, allowing for through-hole tapping applications.
Key Properties
- Color: Red
- Strength: High
- Viscosity: Low (typically 400-600 cP at 25°C)
- Cure Type: Anaerobic
- Chemical Base: Dimethylacrylate ester / Methacrylate
- Fixture Time (Set Time): 5-15 minutes on active metals (e.g., steel)
- Full Cure Time: 24 hours
- Operating Temperature Range: -55°C to +150°C (standard anaerobic adhesives)
- Disassembly Temperature: Requires localized heat to approximately 232-260°C (450-500°F) for removal.
- Max Fastener Size: Up to 1 inch (25mm) or M25
- Specifications: Meets MIL-S-46163A Type I Grade K and ASTM D5363 Group 2 Class 2 Grade 1.
Surface Compatibility
Loctite 271 is suitable for use on all metal fasteners. It is specifically recommended for brass, steel, and stainless steel. It is not recommended for use on plastic parts, especially thermoplastic materials, as it may cause stress cracking. Additionally, it should not be used in pure oxygen or oxygen-rich systems, nor as a sealant for chlorine or other strong oxidizing materials. For inactive metals (such as stainless steel, aluminum, and plated metals) or in low-temperature conditions (below 5°C), an activator like Loctite SF 7649 or SF 7471 may be required to ensure proper cure speed.
Known backups / known substitutes
Several products are considered equivalents or alternatives to Loctite 271 High-Strength Threadlocker:
- 3M Scotch-Weld Threadlocker TL71 Series (High Strength, Red)
- Permatex 271000 Red Threadlocker
- JB Weld 27106 Red Threadlocker
- Pro Seal 27106 Red Threadlocker
- Vibra Tite Red Threadlocker
- Other brands like Loxeal and Threebond also offer high-strength threadlockers that can serve as alternatives.
Comparison Note
Loctite 271 (Red) is distinguished from Loctite 242 (Blue) by its significantly higher strength and permanent locking capabilities. While Loctite 242 (Blue) is a medium-strength, removable threadlocker suitable for parts requiring occasional servicing and can be disassembled with hand tools, Loctite 271 (Red) provides a permanent bond. Disassembly of components secured with Loctite 271 typically requires localized heat application (around 232-260°C or 450-500°F) in addition to tools. Tests have shown Loctite Red to be substantially stronger than Loctite Blue, particularly under load.
