Loctite 572

Overview

Loctite 572 is a medium-strength, slow-curing anaerobic pipe thread sealant formulated for coarse metal threads (e.g. larger pipe sizes and fittings).

It cures in the absence of air and in contact with metal to form a solid, leak-tight seal that resists vibration, fluids and gases, while still allowing disassembly with standard tools during maintenance.

Use Loctite 572 when you want a reliable alternative to PTFE tape and pipe dopes on rigid metal pipework, especially where large threads and higher clearances are involved.

Key Features & Benefits

• Optimized for coarse threads
  Designed for larger, looser-tolerance pipe threads, helping to seal gaps that tapes and pastes can struggle with.

• Medium-strength for serviceable joints
  Provides secure sealing without locking the joint permanently; fittings can be broken loose with normal hand tools.

• Slow, controlled cure
  Longer cure time gives more assembly and alignment time on large installations and complex manifolds.

• Replaces tapes and pastes
  Eliminates thread galling, shredding and creep associated with PTFE tape and traditional pipe compounds.

• Good resistance to industrial fluids
  Suitable for many oils, coolants, fuels and process fluids (always verify compatibility for critical media).

• Helps prevent corrosion and fretting
  Seals the thread spiral, helping keep out moisture and contaminants that can cause rust and seizure.

Typical Applications

Loctite 572 is intended for rigid metal pipe and fittings, including:

• Process piping in industrial plants and workshops

• Hydraulic and low-to-medium pressure pneumatic systems

• Compressed air networks and general utility lines

• Threaded plugs, reducers, elbows, tees and unions in maintenance and repair jobs

• Equipment skids and machinery where vibration and thermal cycling can cause conventional seals to loosen

Typical substrates: carbon steel, stainless steel, brass, bronze and other metallic threads.
(Not recommended for plastic fittings or pure oxygen service unless specifically qualified.)

How Loctite 572 Works

Loctite 572 is an anaerobic methacrylate-based sealant:

1. Apply the liquid to the male thread.

2. As the joint is tightened, the material is distributed through the thread spiral, filling the voids.

3. Once air is excluded and the product is in contact with metal, it cures to a tough thermoset plastic, sealing against liquids and gases and resisting loosening from vibration.

Because it solidifies in the thread, it cannot be extruded or washed out the way tapes and soft pastes can.

Typical Property Snapshot

Values vary by substrate and conditions; always consult the official TDS and test in your own application.

• Technology: Anaerobic thread sealant for metal pipe threads

• Strength level: Medium (allows future disassembly)

• Cure profile: Relatively slow vs. many other thread sealants – ideal where extra assembly time is needed

• Viscosity: Medium to high – formulated to stay on coarse threads without running excessively

• Service temperature: Suitable for typical industrial utility temperatures (check data sheet for exact range)

Directions for Use

1. Prepare the threads

   • Remove oil, grease, dirt, old tape or compound.

   • For best results on passive metals or slightly oily surfaces, use an appropriate Loctite cleaner/primer if available.

2. Apply the product

   • Shake the bottle.

   • Apply a continuous bead of Loctite 572 around the full circumference of the male thread, a couple of threads back from the leading edge.

   • For larger diameters, apply to both male and female threads if needed.

3. Assemble and position

   • Tighten to the recommended torque.

   • Align components within the working time; wipe away any excess sealant squeezed out of the joint.

4. Cure and test

   • Allow sufficient time for the sealant to cure before applying full system pressure.

   • For critical systems, perform a leak or pressure test prior to returning to service.

5. Disassembly

   • Loosen with standard hand tools.

   • If the joint is difficult to move after long service, controlled heat and/or penetrating oil can help.

Storage & Safety

• Store in a cool, dry location, away from heat and direct sunlight.

• Keep the bottle closed when not in use to avoid contamination.

• Follow the Safety Data Sheet (SDS) for PPE, handling and first-aid information.

FAQs

Q1: What is the main difference between Loctite 572 and faster-curing thread sealants?
A: Loctite 572 cures more slowly, giving extra time to position and align large assemblies. This makes it particularly useful on coarse, large-diameter pipework where adjustments are common.

Q2: Can Loctite 572 be used on fine threads?
A: It can seal fine threads, but its strength and cure profile are optimized for coarse metal threads. For small fittings or where faster cure is needed, another Loctite thread sealant may be more suitable.

Q3: Is the joint permanent once Loctite 572 has cured?
A: No. Loctite 572 is medium-strength. Joints are securely sealed but generally serviceable with normal hand tools.

Q4: Do I still need PTFE tape with Loctite 572?
A: No. Loctite 572 is designed to replace PTFE tape and paste, providing sealing and vibration resistance in one product.