What is Loctite 518 used for?

It is a semi-flexible anaerobic gasket sealant designed for rigid metal flange mating surfaces such as steel, iron, and aluminium.

What is the maximum gap fill capability?

It accommodates surface irregularities and fills gaps up to 0.25 mm.

How does Loctite 518 cure?

It cures anaerobically in the absence of air between close-fitting metal surfaces.

Can parts be disassembled after application?

Yes, its medium strength allows parts to be disassembled using standard hand tools.

What is the operating temperature range?

The operating temperature ranges from -55 °C to 150 °C.

LOCTITE 518 surface sealant (25 ml standard tube) - 2125535

Name: LOCTITE 518 surface sealant (25 ml standard tube) - 2125535
Brand: LOCTITE
SKU: 02349035
Price: 25.6 EUR
Availability: PreOrder

Supplier number: LOCTITE 2125535 | EAN 4058093005699

Recommended Retail Price €32.59

25.60 tax incl.

€21.16 excl. VAT (incl. all environmental contributions)

On order: delivered from 13/10/2026

The minimum purchase order quantity for the product is 12.

Ordered before 20:00 - delivered as of 13/10/2026
Free shipping
Delivery by DHL
Delivered from Belgium

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How does it work?

For a purchase value of €99 to €125 excl. VAT, receive FREE LOCTITE 55 thread sealing cord 50 m (IDH 528244) worth €9.99.
For a purchase value of more than €125 excl. VAT, receive FREE LOCTITE SF 7850 hand cleaner 400 ml (IDH 2098250) worth €13.21.
The free item is automatically added to your order. No registration is required.
The promotion is valid from 01.10.2026 to 31.10.2026.
Loctite Buy & Get deals are recognisable by the promotion label on the product page. Click the label to view all available deals.

Reliable flange sealing with Loctite 518

Practical benefits

Instant seal against pressure: You achieve an immediate low-pressure seal on rigid metal flanges, allowing you to complete assemblies quickly without waiting for full cure.
High tolerance to contamination: You get dependable adhesion on steel, cast iron, and aluminum surfaces, even when minor oil or surface contaminants are present.
Easy disassembly during maintenance: Thanks to the semi-flexible cured layer, you easily disassemble connected components during servicing without damaging precision-machined mating faces.

In a nutshell

The right choise for

With Loctite 518 flange sealant, you create a dependable and immediate seal on rigid metal flanges and mating surfaces. This semi-flexible liquid gasketing material cures anaerobically between close-fitting components made of steel, cast iron, and aluminium. It delivers an instant low-pressure seal while filling surface irregularities and gaps up to 0.25 mm. Even on surfaces with minor oil residue, it provides excellent adhesion to prevent fluid and gas leaks in engine blocks, gearboxes, and pump housings. Operating reliably from -55 °C to 150 °C, its medium strength ensures durable sealing performance while allowing quick disassembly during maintenance using standard hand tools without damaging precision mating faces.

Product information FAQ

€25.60

tax incl.

Key features according to our expert

Net volume: 25 ml
ADR packing group: Not applicable
ADR class: Not applicable
Principal hazard property: GHS07 Harmful or irritant
UN number: Not applicable
P-statements: P101; P102; P273; P280; P302 + P352; P333 + P313; P337 + P313; P501
H-statements: H315; H317; H319; H412
Hazard class: GHS07 Harmful or irritant
Physical state: Liquid
Flash point: > 100 °C

Product description:

LOCTITE 518 cures when confined in the absence of air between close-fitting metal surfaces.
It is an anaerobic gasketing material designed for use on rigid iron, aluminum, and steel flanged mating surfaces.
Fills gaps up to 0.25mm and forms a flexible, chemical-resistant seal that will not tear or decay.
Parts disassemble easily, even after extended service.
Typical applications include sealing close-fitting joints between rigid metal faces and flanges.
It is also used as a formed-in-place gasket on rigid flanged connections, e.g. transmissions and motor housings.
NEW: Henkel has recently improved the product formulation of LOCTITE 518 providing:
Higher strength on contaminated surfaces
Better flexibility and improved adhesion
Enhanced sealing capability
Improved gap cure
High performance on passive metals without an activator

Precautionary statements

P101: If medical advice is needed, have product container or label at hand.
P102: Keep out of reach of children.
P273: Avoid release to the environment.
P280: Wear protective gloves/protective clothing/eye protection/face protection.
P302 + P352: IF ON SKIN: Wash with plenty of water/…
P333 + P313: If skin irritation or rash occurs: Get medical advice/attention.
P337 + P313: If eye irritation persists: Get medical advice/attention.
P501: Dispose of contents/container to ... (see safety data sheet).

Hazard statements

H315: Causes skin irritation.
H317: May cause an allergic skin reaction.
H319: Causes serious eye irritation.
H412: Harmful to aquatic life with long lasting effects.

All Features

Net volume: 25 ml
Adr packing group: Not applicable
Adr class: Not applicable
Principal hazard property: GHS07 Harmful or irritant
Un number: Not applicable
P-statements: P101; P102; P273; P280; P302 + P352; P333 + P313; P337 + P313; P501
H-statements: H315; H317; H319; H412
Hazard class: GHS07 Harmful or irritant
Physical state: Liquid
Flash point: > 100 °C

Brand LOCTITE
02349035
EAN 4058093005699
Supplier number LOCTITE 2125535

Frequently asked questions about this product

Answered by specialists

What is Loctite 518 used for?: It is a semi-flexible anaerobic gasket sealant designed for rigid metal flange mating surfaces such as steel, iron, and aluminium.
What is the maximum gap fill capability?: It accommodates surface irregularities and fills gaps up to 0.25 mm.
How does Loctite 518 cure?: It cures anaerobically in the absence of air between close-fitting metal surfaces.
Can parts be disassembled after application?: Yes, its medium strength allows parts to be disassembled using standard hand tools.
What is the operating temperature range?: The operating temperature ranges from -55 °C to 150 °C.