LOCTITE 55 – Universal thread sealing cord for metal and plastic pipe threads

LOCTITE 55 – Universal thread sealing cord for metal and plastic pipe threads

LOCTITE 55 is an instant sealing thread sealant for the fast, safe and flexible sealing of metal and plastic pipe threads – ideal for water, gas, hydrogen and drinking water applications.

Product Description

LOCTITE 55 is a multifunctional, coated polyamide thread with a chemically inert special paste, used as a sealant for tapered and cylindrical pipe threads made of metal and plastic. The product is wound directly onto the thread from the convenient dispenser and provides an immediate, reliable seal without any curing time. LOCTITE 55 is universally applicable for cold and hot water, drinking water, gas (including LPG and hydrogen), and numerous industrial media.

Unlike PTFE tape, LOCTITE 55 can be rotated back up to 45° after installation without losing its sealing effect – ideal for flexible adjustment of fittings and threaded connections. The seal remains permanently reliable, even under vibration, temperature fluctuations, and pressure loads up to 69 MPa. The product is ready for immediate use and facilitates quick installation on-site or in the workshop.

Thanks to numerous international approvals (including DVGW, KIWA, NSF, WRAS, EN 751-2, BS 6920), LOCTITE 55 is approved for use on drinking water, gas, and hydrogen lines, as well as in commercial, industrial, and residential installations. The sealant is vapor-compatible and resistant to many industrial liquids and gases.

Product properties

• Technology: coated polyamide multifilament thread
• Color: white
• Sealing effect: immediate, no curing required
• Temperature range: -10 °C to +149 °C (briefly up to 150 °C)
• Pressure resistance: up to 69 MPa
• Media resistance: Water, hot water, gas, hydrogen, steam, oil, many industrial media
• Reversible rotation: adjustable up to 45° without leakage
• Spool sizes: 12 m, 50 m, 100 m, 160 m
• Specific density: 1,25
• Coating application: 0.54–0.74 g/m²
• Lubricability (K-value): 0.15–0.16 (ASTM D5648)
• Storage: 8 °C to 21 °C, store in a dry place

Approvals and certifications

• DVGW/KTW (Gas & Drinking Water)
• EN 751-2 Class ARp
• ANSI/NSF Standard 61 (drinking water up to 82 °C)
• WRAS (British Standard BS 6920 for drinking water)
• KIWA GASTEC QA AR 214 (hydrogen gas mixtures up to 100% hydrogen)
• Australian Gas Association
• WRC and BGA KTW for cold and hot drinking water

Suitable materials

• Metallic pipe threads (steel, brass, copper, galvanized, etc.)
• Plastic pipe threads (e.g. PVC, PP, PE)

Typical application areas

• Sealing of water, heating and gas pipes
• Installation of drinking water and hot water systems
• Sealing of hydrogen and gas pipelines
• Pipe fittings in industry and plant engineering
• Building services, plumbing, heating, air conditioning
• Installations using steam, compressed air or aggressive media

Processing instructions

1. Cleaning: Clean the threads with a wire brush before application.
2. Application: Place the thread end approximately two thread turns away from the end on the external thread and hold it in place.
3. Wrapping: Wrap thread onto the pipe thread in the direction of the thread, filling the base of the thread (number of wraps depending on material and diameter, e.g. 6–8 for ½" metal, 12–15 for ½" plastic).
4. Cutting: Use the integrated cutting tool to cut the thread, then place the loose end onto the thread.
5. Assembly: Screw fittings together; readjustment up to 45° is possible.
6. Immediate sealing effect: The system can be put into operation directly after installation.