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Medium-strength, thread sealant

Main Category: All Systems
SKU: LOCTITE 577
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Medium-strength, thread sealant

Medium-strength, general purpose thread sealant for straight/straight and straight/taper threads and fittings. Fills the space between threaded parts and seals and locks at the same time.

LOCTITE® 577 is designed for the locking and sealing of metal pipes and fittings as well as other threaded assemblies. The product provides an instant, low-pressure seal for metal pipes and fittings. It will not creep, shrink or shred. It has excellent chemical and thermal resistance and offers less migration of liquid product after application.

Excellent chemical resistance

Instant low pressure seal

Suitable for all metals

Medium-strength, general purpose thread sealant for sealing metal threads

Locks connection against vibration-induced loosening and other stresses

Easy to apply

Cures on active and inactive metals

NSF P1 Reg. No. 123001

DVGW Approval (EN 751-1): DVGW Reg. No. NG-5146CQ0312

Technical Information

Agency Approvals / Specifications DVGW, WRAS, NSF
Breakaway Torque, Steel M10 33.0 N·m (295.0 in./lb. )
Colour Yellow
Key Characteristics Thixotropic, General Purpose, Strength: Medium Strength
Operating Temperature -55.0 - 150.0 °C (-65.0 - 300.0 °F )
Viscosity, 20 RPM 25000.0 mPa·s

Step by Step Guide

1. Preparation

Cleaning - It is recommended to use LOCTITE SF 7649 solvent-based activator for surface preparation to degrease and clean surfaces prior to applying adhesive.
Activation - With passive metals (stainless steel, aluminium and plated metals), use activator LOCTITE® 7649 (see cure speed vs activator graph in the TDS).

2. Application

Apply a 360° bead to the leading male thread, leaving the first thread free.

For bigger threads, apply both on male and female threads.

(Recommended dispensing equipment: IDH 608996 50ml Hand Pump or IDH 88631 Peristaltic handgun 97001)

3. Assembly

Assemble fittings using wrench tightening in accordance with manufacturers' recommendations.

4. Disassembly

Disassemble with standard hand tools.

If not possible, apply localised heat to approximately 250°C, disassemble while hot.

For corroded or seized parts use LOCTITE® 8040 Freeze and Release.