Threadlocker High-Strength – SUPEX 680 Permanent Bolt Lock

Benefit	Mechanism
Vibration Resistance	Completely fills 100% of the microscopic thread air gap, preventing transverse micro-movement that causes self-loosening.
Corrosion Prevention	Seals the thread root against moisture, process chemicals, oils, and road salt, stopping galvanic corrosion and thread seizure.
Prevents Back-Off from Thermal Expansion	Maintains clamp load even through repeated thermal cycles where mechanical lock washers yield or deform.

Property	Typical Value
Chemical Type	Dimethacrylate / Triacrylate
Appearance	Green
Viscosity	1,800–3,200 cPs
Breakaway Torque	50–60 N·m
Prevail Torque	22–28 N·m
Shear Strength	25–39 N/mm²
Fixture Time	≤15 minutes
Full Cure @ 20°C	24 hours
Maximum Gap Fill	0.25 mm
Operating Temperature	-50°C to +200°C
Shelf Life @ 20°C	12 months

1. What is a high-strength anaerobic threadlocker?

It is a single-component, liquid-to-gel chemical adhesive formulated to permanently lock and seal threaded metal fasteners. It cures (hardens) strictly under anaerobic conditions—meaning in the absence of air (oxygen) and in the presence of active metal ions.

2. What color is high-strength threadlocker typically?

In standard industrial coding, high-strength threadlocker is red. Medium-strength formulations are typically blue, and low-strength formulations are typically purple.

3. What is the difference between medium-strength (blue) and high-strength (red) threadlocker?

Medium-Strength: Removable using standard hand tools (wrenches, ratchets) without heating. Ideal for parts requiring routine servicing.
High-Strength: Permanent. It delivers significantly higher breakaway and prevailing torque. Disassembly requires localized high heat alongside hand tools.

Application & Compatibility

4. What fastener sizes can high-strength threadlocker handle?

Most standard high-strength grades effectively lock fasteners up to M20 to M36 (approx. 3/4″ to 1.5″ diameter). Fasteners with larger diameters or wider thread pitches may require higher-viscosity formulations to bridge the thread gaps.

5. Does it work on all metals?

It cures best on active metals (iron, plain steel, copper, brass, bronze). On passive metals (stainless steel, aluminum, titanium, zinc-plated, or galvanized fasteners), the curing speed slows down, and an anaerobic activator/primer is recommended to achieve full strength.

6. Can it be used on plastic fasteners or threaded plastic pipes?

No. Anaerobic threadlockers require metal ions to trigger the polymerization reaction. Furthermore, the liquid chemistry can attack, soften, or stress-crack many thermoplastics (e.g., ABS, polycarbonate, acrylic).

7. How should threads be prepared before applying?

Threads should be clean and dry. Degrease surfaces using an industrial solvent or fast-evaporating cleaner (like acetone or brake/parts cleaner) to remove residual cutting oils, rust inhibitors, and dirt. While many modern formulas tolerate light oil films, degreased threads yield maximum bond strength.

Curing & Performance

8. How long does high-strength threadlocker take to cure?

Fixture time: 10 to 30 minutes (parts can be handled, but not loaded).
Functional strength: 1 to 3 hours (light operating load).
Full cure: 24 hours at room temperature (~22°C / 72°F).
Note: Curing is slower in cold temperatures or on passive metals.

9. What temperatures can it withstand?

Standard high-strength threadlockers typically operate reliably between -55°C and +150°C (-65°F to +300°F). Specialized high-temperature grades can withstand continuous temperatures up to +200°C to +230°C (+400°F to +450°F).

10. Is it resistant to fuels, oils, and automotive fluids?

Yes. Once fully cured, the thermoset polymer cross-links into a solid plastic that resists motor oils, diesel, gasoline, transmission fluid, glycol/water mixtures, hydraulic fluids, and most mild industrial chemicals.

Disassembly & Removal

11. Can high-strength threadlocker ever be disassembled?

Yes, but it is not meant for routine removal. To disassemble without shearing the fastener:

Apply localized heat directly to the nut/bolt interface using a heat gun, mini induction heater, or torch until the joint reaches approximately 250°C (482°F).
The heat softens the cured polymer resin.
Unscrew the fastener immediately while hot using standard hand tools.

12. How do you clean cured threadlocker residue before reassembly?

Cured anaerobic polymer is insoluble in standard solvents. Remove bulk residue mechanically using a wire brush, wire wheel, or tap/die chase. A methylene-chloride-based or specialized gasket/adhesive stripper can help soften stubborn residue.

Storage & Handling

13. Why are threadlocker bottles only half full?

Anaerobic adhesives require dissolved oxygen to remain liquid in the bottle. The special low-density polyethylene (LDPE) packaging is gas-permeable, and the headspace ensures the liquid continuously receives enough air exposure to prevent it from curing inside the bottle.

14. What is the typical shelf life?

Stored in original, sealed containers in a cool, dry place (ideally between 8°C and 21°C / 46°F and 70°F), most high-strength threadlockers have an unopened shelf life of 24 months from the date of manufacture.