Loctite EA 3478 Superior Metal - 1Kg

LOCTITE EA 3478, also known as LOCTITE 3478 Superior Metal, is a high-strength, two-component, ferro-silicon-filled epoxy repair compound designed for rebuilding, resurfacing and restoring worn or corroded metal components.

It is formulated for demanding industrial maintenance applications where damaged metal surfaces need to be rebuilt and subsequently machined to restore the original dimensions or tolerances. The cured material provides high compressive strength and excellent resistance to corrosion, abrasion and chemical attack.

Key Features

Two-component ferro-silicon-filled epoxy

Designed for metal rebuilding and repair

High compressive strength

Excellent machinability after curing

Resists corrosion and abrasion

Good resistance to chemical attack

Cures to a metal-like finish

Suitable for restoring worn shafts and bearing housings

Can repair worn keyways and damaged housings

Suitable for filling pitted and eroded metal surfaces

Helps restore dimensional tolerances

Room-temperature curing system

Designed for industrial maintenance and repair applications

Typical Applications

LOCTITE EA 3478 is particularly suitable for rebuilding metal components affected by mechanical wear, corrosion and surface deterioration.

Worn Shaft Repair

The compound can be used to rebuild worn areas on shafts. Once cured, the repaired surface can be machined to restore the required dimensions and fit.

Bearing Housing Repair

LOCTITE EA 3478 can restore worn or damaged bearing housings, helping rebuild the material required to obtain an appropriate bearing fit.

Keyway Repair

It can be used to rebuild worn keyways and damaged keyed connections where material has been lost through mechanical wear.

Damaged Housing Repair

The epoxy can be applied to worn or damaged metal housings to restore missing material and provide a machinable repair surface.

Pitted Metal Surfaces

The material is suitable for filling pitted, corroded and eroded surfaces in machinery and metal components.

Corrosion Damage

Its resistance to corrosion, abrasion and chemical attack makes it suitable for selected repairs where the component has suffered deterioration from aggressive operating conditions.

Ferro-Silicon-Filled Formulation

A major characteristic of LOCTITE EA 3478 is its ferro-silicon filler system.

The formulation is designed to produce a hard, metal-like repair surface with high compressive strength. This makes it particularly suitable for rebuilding worn metal components that subsequently require machining to restore their original geometry.

Henkel specifically describes the product as a ferro-silicon-filled epoxy system with excellent machinability and outstanding compression strength.

Excellent Machinability

After curing, LOCTITE EA 3478 can be machined to restore dimensions and tolerances.

This characteristic is particularly valuable for:

Shaft rebuilding

Bearing housing restoration

Keyway repair

Worn machine surfaces

Damaged housings

Pitted metal surfaces

The repair can therefore be applied slightly oversized and subsequently machined where the application permits.

Corrosion, Abrasion and Chemical Resistance

LOCTITE EA 3478 is formulated to resist corrosion, abrasion and chemical attack, making it suitable for industrial maintenance environments where repaired surfaces may be exposed to mechanical wear or aggressive operating conditions.

Henkel also states that the cured product does not rust like conventional metal-filled epoxies.

Mixing Ratio

LOCTITE EA 3478 is supplied as a two-component resin and hardener system.

Mix ratio:

By weight: 7.25 : 1

By volume: 4 : 1

The resin is metallic gray and the hardener is white. After mixing, the compound becomes gray.

Thorough mixing is important to obtain a uniform repair material and consistent curing.

Working Life and Cure

The typical working life is approximately:

20 minutes at 25°C

Henkel lists a typical fixture time of approximately:

6 hours

The material cures at room temperature after mixing. Actual cure time can vary with temperature, repair thickness, substrate condition and other application factors.

For maximum properties, the manufacturer's technical data should be followed for the applicable cure schedule.

Typical Mechanical Properties

Typical values reported in the LOCTITE technical documentation include:

Property

Typical Value

Technology: Epoxy

Components: 2-part resin + hardener

Mixed appearance: Gray

Mix ratio by volume: 4 : 1

Mix ratio by weight: 7.25 : 1

Working lif: 20 minutes

Fixture time: 6 hours

Shear strength: 17 N/mm²

Application temperature: 15°C to 30°C

Cure: Room-temperature cure

The reported shear-strength value is a typical value, not a guaranteed specification for every application.

Cured Material Performance

The technical data sheet reports typical cured properties after curing at 25°C, including approximately:

Shore hardness: 90 D

Compressive strength: 125 N/mm²

Tensile strength: 38 N/mm²

Steel lap shear strength: 17 N/mm²

These values are typical laboratory results and actual performance depends on surface preparation, joint design, curing conditions and service environment.

Surface Preparation

Proper surface preparation is essential for achieving reliable adhesion.

Recommended preparation includes:

Remove oil, grease, dirt and other contaminants.

Remove loose rust, scale and damaged material.

Abrade or grit-blast the surface where appropriate.

Remove dust and loose particles.

Degrease the prepared surface.

Ensure the surface is dry and properly prepared before mixing and applying the epoxy.

For critical industrial repairs, follow the latest Henkel technical documentation for the exact preparation procedure.

Application Procedure

Prepare and clean the damaged metal surface.

Mechanically roughen the surface where required.

Measure the resin and hardener according to the specified mixing ratio.

Thoroughly mix the two components until a uniform gray colour is obtained.

Apply the mixed compound to the damaged or worn area.

Build the material slightly above the desired final dimension when subsequent machining is required.

Allow the compound to cure.

Machine, grind or finish the repaired area as required.

Inspect the repaired component before returning it to service.

Advantages for Industrial Maintenance

Restores Worn Components

EA 3478 can rebuild missing material on worn metal parts instead of requiring immediate replacement of the entire component.

Machinable Repair

Its machinability allows repaired surfaces to be brought back to required dimensions and tolerances.

High Compression Strength

The ferro-silicon-filled formulation provides high compressive strength for suitable rebuilding applications.

Resists Harsh Conditions

Resistance to corrosion, abrasion and chemical attack makes it suitable for demanding industrial maintenance environments.

Helps Reduce Downtime

By rebuilding worn components in place or during maintenance, the product can help reduce equipment downtime and the need for replacement components. Henkel specifically describes it as a material that rebuilds worn parts fast.

Industries and Equipment

LOCTITE EA 3478 is primarily associated with industrial maintenance and repair applications.

Typical equipment and components include:

Industrial machinery

Pumps

Shafts

Bearing housings

Gear housings

Machine housings

Keyways

Flanges and metal surfaces

Rotating equipment

Corroded machinery

Manufacturing equipment

General plant maintenance equipment

Packaging

Henkel's India product listing currently identifies LOCTITE EA 3478, 1 kg Tub, with IDH/part number 680035. Other markets list different package configurations, including 453 g and 500 g formats, so packaging should be confirmed for the specific market and SKU being sold.

Important Application Consideration

LOCTITE EA 3478 is an industrial metal-rebuilding epoxy, not a universal replacement for welding or component replacement.

For safety-critical, pressure-containing, structural or highly loaded equipment, the suitability of an epoxy repair should be evaluated according to the equipment manufacturer's requirements, engineering procedures and applicable standards.

Product Summary

LOCTITE EA 3478 is a high-strength, ferro-silicon-filled epoxy repair compound for rebuilding worn, corroded and damaged metal components. Its excellent machinability, high compressive strength and resistance to corrosion, abrasion and chemical attack make it suitable for restoring worn shafts, keyways, bearing housings, machine housings and pitted metal surfaces. It cures at room temperature and is designed for demanding industrial maintenance and metal-rebuilding applications.