Thread Sealants

Seal, Secure, and Protect Threaded Connections

Prevent leaks, resist vibration, and ensure long-term reliability with LOCTITE® Thread Sealants.
Engineered for metal pipe fittings and threaded connections, our anaerobic sealants cure in the absence of air and presence of metal to form a durable, pressure-resistant seal that will not shrink, crack, or loosen over time.

What Is a Thread Sealant?

A thread sealant is a single-component adhesive that fills the gaps between metal threads, preventing the escape of liquids or gases.
Unlike PTFE tape or paste, LOCTITE sealants cure into a solid thermoset plastic when confined between metal surfaces, delivering a permanent, leak-proof seal that withstands vibration, temperature extremes, and pressure surges.

Thread sealants vs. threadlockers:
While both cure anaerobically, threadlockers prevent loosening, and thread sealants prevent leakage—many LOCTITE grades combine both functions.

How LOCTITE Thread Sealants Work

1. Applied to male or female threads, the liquid sealant fills microscopic voids.

2. As the fitting is assembled, oxygen is excluded and the sealant begins to cure.

3. The cured polymer forms a resilient, chemical-resistant barrier that locks threads and seals against pressure.

This mechanism ensures consistent sealing even in harsh environments, from hydraulic systems to chemical pipelines.

How to Choose the Right Thread Sealant?

When selecting a LOCTITE thread sealant, consider:

• Pressure and temperature – operating and peak conditions

• Fluid type – oil, gas, water, chemicals

• Thread type – tapered or straight, fine or coarse

• Material – steel, stainless steel, brass, aluminum

• Disassembly – permanent or serviceable joints

• Cure speed – production line or maintenance use

Where to Use Thread Sealants

LOCTITE thread sealants are trusted in a wide range of industries:

• Piping systems & plumbing – water, steam, gas, and chemical pipelines

• Hydraulic and pneumatic systems – fittings exposed to pressure and vibration

• Automotive & heavy equipment – coolant, brake, and fuel systems

• Industrial maintenance & MRO – pumps, valves, compressors, and instrumentation

• Manufacturing & process plants – oil & gas, chemical, and power sectors

They prevent leakage, protect threads from corrosion, and simplify disassembly during maintenance.

Why Choose LOCTITE Thread Sealants?

• No creep, shrinkage, or cracking
• Prevents galling and corrosion
• Provides instant low-pressure seal
• Long-term durability under pressure and temperature cycling

Application Instructions

1. Prepare surfaces: Clean threads of oil, dirt, and debris using LOCTITE SF 7070 or equivalent cleaner.

2. Apply sealant: Dispense 360° around male threads or into female fitting. Avoid over-application.

3. Assemble parts: Tighten as required; product spreads evenly into gaps.

4. Allow curing: Fixture in minutes; full cure within 24 hours (varies by metal and temperature).

5. Disassemble (if needed): Use hand tools or apply localized heat for high-strength grades.

Pro tips:

• Use primer for passive metals (e.g. stainless steel, zinc, aluminum).

• Do not apply to wet or contaminated surfaces.

• Store between 8 °C and 21 °C for maximum shelf life.