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LOCTITE 2400 Threadlocker for Reliable Metal Fastener Locking

LOCTITE 2400 Threadlocker is a one-component, medium-strength anaerobic adhesive designed to lock and seal threaded metal fasteners that may require later servicing with standard hand tools. The blue liquid cures when confined without air between close-fitting metal surfaces, helping prevent bolts, nuts, and studs from loosening or leaking under shock, vibration, and normal equipment operation.

This product is particularly suitable for less-active substrates such as stainless steel, zinc-flake-coated steel, zinc-plated fasteners, and other treated metal surfaces. Its thixotropic formulation reduces migration after dispensing, helping the liquid remain around the threaded engagement area instead of flowing onto adjacent parts. It also fluoresces under ultraviolet light, allowing production personnel to inspect adhesive coverage during assembly.

Key Benefits of LOCTITE 2400 Threadlocker

LOCTITE 2400 Threadlocker is based on dimethacrylate-ester technology and requires no resin-to-hardener mixing. The uncured material has a typical specific gravity of approximately 1.1 and a Brookfield viscosity of around 3,100 mPa·s at 25°C. Cone-and-plate testing gives a representative viscosity of approximately 350 mPa·s at the specified shear rate.

Henkel lists a typical fixture time of approximately ten minutes and suitability for metal threads up to M36. The medium-strength bond is intended to provide dependable resistance to vibration while still permitting normal maintenance disassembly with common hand tools. Cure speed depends on fastener material, thread clearance, temperature, and the presence of an activator.

After curing for 23 hours at 23°C, the November 2024 technical data sheet reports a typical breakaway torque of approximately 25 N·m on M10 steel nuts and black-oxide steel bolts. Representative breakaway torque on M10 zinc-flake fasteners is approximately 19 N·m, while compressive shear strength on steel pins and collars is around 11 N/mm². These values are typical laboratory results rather than guaranteed specifications for every assembly.

LOCTITE 2400 Threadlocker also demonstrates resistance to motor oil, water-glycol coolant, unleaded petrol, diesel fuel, brake fluid, acetone, and ethanol under Henkel’s published ageing conditions. Actual durability depends on fluid concentration, temperature, exposure time, thread geometry, substrate condition, and mechanical load.

Applications for LOCTITE 2400 Threadlocker

LOCTITE 2400 Threadlocker is suitable for pumps, electric motors, gearboxes, presses, machine tools, compressors, industrial automation equipment, automotive components, electrical machinery, and general maintenance assemblies. Typical uses include securing mounting bolts, housing screws, threaded shafts, studs, brackets, covers, and other metal fasteners exposed to vibration.

The product can be used on steel, stainless steel, aluminum, brass, zinc-plated steel, and zinc-flake-coated fasteners. Henkel also lists WRAS approval to BS 6920 under reference 1104507. Approval scope should be checked for the intended market, package, water system, and operating conditions before use in regulated applications.

How to Apply LOCTITE 2400 Threadlocker

Before applying LOCTITE 2400 Threadlocker, clean the internal and external threads with a compatible LOCTITE cleaning solvent and allow them to dry. Shake the bottle thoroughly. For through holes, apply several drops around the bolt where the nut will engage. For blind holes, place several drops on the lower third of the internal threads or into the bottom of the hole. Assemble and tighten the fastener according to the required torque specification.

When cure speed is too slow or the joint contains a larger gap, LOCTITE SF 7471 or LOCTITE SF 7649 activator may be applied and allowed to dry before assembly. Uncured excess can be removed with LOCTITE SF 7063 or a similar compatible cleaner. Most assemblies can be dismantled using standard hand tools; unusually long thread engagement may require localized heating to approximately 250°C before hot disassembly.

Storage and Safety of LOCTITE 2400 Threadlocker

Store unopened LOCTITE 2400 Threadlocker in a dry location between approximately 8°C and 21°C. Storage below 8°C or above 28°C may affect product properties. Do not return dispensed material to the original container. The product is not recommended for pure oxygen, oxygen-rich systems, chlorine, strong oxidizers, or unvalidated thermoplastic applications.

For manufacturers seeking medium-strength locking with easier maintenance removal, LOCTITE 2400 Threadlocker provides dependable vibration resistance, improved curing on inactive metals, controlled thixotropic application, and UV inspection capability. Explore our medium-strength threadlockers for bolts, nuts, studs, pumps, motors, gearboxes, machinery, and industrial maintenance.

medium-strength threadlockers