Loctite 620 Retaining Compound(tube)

LOCTITE 620 is a medium-to-high-strength anaerobic retaining compound formulated for bonding cylindrical fitting parts, with particular strength in applications involving larger bond gaps (up to 0.2mm) and elevated service temperatures. This green methacrylate ester adhesive is engineered to deliver robust, reliable curing performance where standard retaining compounds may fall short on gap-filling or thermal demands.

Key Features

LOCTITE 620's high viscosity (8,500 mPa·s) sets it apart from lower-viscosity retainers, allowing it to bridge wider gaps between cylindrical mating parts without excessive run-off. Its standout performance characteristic is high-temperature capability — LOCTITE 620 is specifically suited for retaining higher-temperature assemblies, making it the preferred choice over standard-strength retainers for thermally demanding rotating equipment. As a one-component anaerobic adhesive, it requires no mixing and cures fully confined between close-fitting metal surfaces.

Performance Data

After 24 hours of cure at 23°C, LOCTITE 620 achieves compressive shear strength of 17 N/mm² on steel pins and collars — and remarkably, this strength increases to 24 N/mm² after a follow-up cure of 24 hours at 177°C, demonstrating genuine thermal enhancement rather than degradation. Hot-strength testing shows the adhesive actually exceeds 100% of room-temperature strength in the 50–150°C range before gradually declining at higher temperatures up to 250°C. Heat-aging data through 5,000 hours at 120°C, 150°C, and 180°C confirms long-term thermal stability, and chemical resistance testing shows excellent retention in motor oil, unleaded petrol, and brake fluid.

Applications

LOCTITE 620 retaining compound is specifically engineered for locating pins in radiator assemblies and bearings in automatic transmissions — applications where both wider bond gaps and sustained high temperatures are the norm. It's also used for locking bushings and sleeves into housings and onto shafts across general high-temperature industrial equipment, automotive powertrain components, and machinery exposed to continuous thermal cycling.

Directions for Use

Clean all bonding surfaces with a LOCTITE cleaning solvent before assembly. Use activator to accelerate cure speed or when working with larger gaps. For slip-fitted assemblies, apply around the leading edge of the male part and inside the female part, using a rotating motion for even coverage. For press-fitted assemblies, coat both surfaces thoroughly and assemble at high press-on rates. For shrink-fitted assemblies, coat the part being inserted into a heated or cooled mating part, avoiding condensation on cooled surfaces. Disassembly requires localized heating to approximately 300°C, or mechanical aids if that temperature isn't achievable.

Why Buy From Tapemart

Tapemart carries genuine LOCTITE 620 medium-to-high-strength, high-temperature retaining compound as part of our full LOCTITE bearing and bushing retainer range. As an authorized LOCTITE distributor, we help automotive and industrial customers select retaining compounds engineered for thermal extremes and gap-filling demands. Order LOCTITE 620 from Tapemart for dependable high-temperature retention in your most demanding rotating assemblies.