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LOCTITE 518 Gasket Sealant

Known as Loctite 518 Gasket Eliminator Flange Sealant

Features and Benefits

Available sizes:

LOCTITE 518 is a medium-strength, general purpose gasketing product with excellent contamination tolerance. Ideal for use on casted iron, steel and aluminum flanges.
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. LOCTITE 518 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.
  • Semi-flexible, medium-strength anaerobic flange gasket
  • For active and inactive rigid metal flanges
  • Cures through minor surface contamination
  • Adapts to flange surface irregularities and gaps up to 0.25 mm
  • Gel-type consistency
  • Seals instantly against low pressure
  • Reduces inventory costs – no need for large inventory of cut gaskets
  • Resists high pressure when fully cured
  • No compression set or misaligned gaskets
  • Easy to automate
  • Reduces process costs – eliminates manual assembly of conventional gaskets
  • NSF P1 Reg. No. 123758
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Documents and Downloads

Safety Data Sheets and RoHs
LOCTITE 518 PEN, 25ml 2392164 en-US
IDH: 2392164
EAN: 079340013001

Size Case: 25 ml Bottle

Quantity: 12.0/case

No documents found

Technical Information

Application Method Dispense System, Manual
Applications Rigid Assembly Gasketing, Sealing
Color Red
Cure Type Anaerobic Cure
Fixture Time, Steel 25.0 min.
Gap Fill, Unprimed 0.25 mm
Key Characteristics Thixotropic, For machined, rigid flanges, Fluorescent, Strength: Medium Strength, Immediate Low Pressure Sealing, Surface Contamination-Tolerant
Operating Temperature -55.0 - 150.0 °C (-65.0 - 300.0 °F )
Physical Form Gel
Specific Gravity, @ 25.0 °C 1.1
Substrates Metal: Aluminum, Metal: Iron - Cast Iron, Metal: Steel, Metal: Passive Metal
Technology Acrylic
Viscosity 750000.0 mPa·s (cP)

How to

Step by Step Guide

1. Preparation - Cleaning

Apply LOCTITE® SF 790™ to old gasket or gasket sealants and use a wood or plastic scraper to remove residues from flange surfaces. Remove burrs. It is recommended to use LOCTITE® SF 7070™ to degrease and clean surfaces prior to applying the sealant.

2. Preparation - Activation

If cure speed of LOCTITE® 518™ is too slow due to passive metals or low temperature (below 5°C), use LOCTITE® SF 7649™ activator. Allow to dry.

3. Application

Apply a continuous bead of sealant onto one flange surface. Place the bead close to the inner rim of the flange and encircle all bolt holes. Small surface scratches will be filled by the adhesive. LOCTITE® 518™ can also be applied by roller onto larger flanges.

4. Assembly

Assemble flanges and tighten bolts as soon as possible. Wipe away any excess squeeze-out, as this will not cure when exposed to air due to sealant's anaerobic curing properties.

5. Disassembly

Disassemble bolts with standard hand tools. Use jacking-screws, cast-on bosses or recesses to lift flanges apart. Once disassembled, apply LOCTITE® SF 790™ on old sealant and use a wood or plastic scraper to remove residues from flange surfaces. For corroded or seized parts, use LOCTITE® LB 8040™ Freeze and Release.

Where to Buy

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LOCTITE 518
LOCTITE 518 is a medium-strength, general purpose gasketing product with excellent contamination tolerance. Ideal for use on casted iron, steel and aluminum flanges.

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