Loctite
Loctite is the adhesives and sealants brand of the Henkel group. For compressed air, water and gas lines we offer three thread sealants, the Loctite 620 retaining compound and the Loctite 55 sealing cord.
Loctite adhesives are anaerobic: they stay liquid in the bottle and only cure inside the thread, where air cannot reach them. They fill the gap between the threads, so the joint seals and will not work loose under vibration or shock.
Technical data sheets in CzechWhich Loctite for which joint
Loctite 511 — low strength
For joints you will take apart. White paste for threaded metal pipes and fittings.
- cures quickly
- loosens with an ordinary spanner
- 50 and 250 ml packs
Loctite 542 — medium strength
Pipes and fittings in pneumatics. A thin brown liquid that seals and locks metal pipes and fittings.
- flows easily into fine threads
- joint resists vibration and shock
- 10, 50 and 250 ml packs
Loctite 577 — medium strength
All-round thread sealant. A yellow paste that does not run and cures even on stainless steel without an activator.
- tolerates slightly oily threads
- fills gaps up to 0.25 mm
- DVGW certificate for gas
Loctite 620 — retaining compound
For cylindrical joints, not threads. A green adhesive that holds close-fitting parts, such as a bearing in its housing.
- gap up to 0.2 mm
- medium to high strength
- withstands high temperatures
Loctite 55 — sealing cord
Does not cure, the joint can be adjusted. Cord for tapered and parallel threads on metal and plastic pipes.
- threads up to 6″
- can be turned back up to 45° after tightening
- approved for drinking water
Looking for PTFE tape, a sealing ring or an adhesive from our own HiSEAL brand? Everything for sealing threads is in one category.
Everything for sealing threadsLoctite adhesives side by side
| Type, use, strength and pack size | ||||
|---|---|---|---|---|
| Type | Use | Strength | Appearance | Pack |
| Loctite 511 | sealing threaded metal pipes and fittings | low | white paste | 50 and 250 ml |
| Loctite 542 | sealing and locking metal pipes and fittings | medium | brown liquid | 10, 50 and 250 ml |
| Loctite 577 | sealing metal threads, stainless steel without an activator | medium | yellow paste | 50 and 250 ml |
| Loctite 620 | retaining close-fitting cylindrical parts | medium to high | green liquid | 50 and 250 ml |
| Loctite 55 | sealing metal and plastic threads up to 6″ | does not cure | white cord | 50 and 150 m |
The higher the strength, the more force you need to undo the joint.
How to apply thread adhesive
1. Clean
Clean and degrease the male and female threads and let them dry.
2. Apply
Apply a bead of adhesive all around the leading threads, leaving the first thread free. On larger threads, apply adhesive inside the nut as well.
3. Tighten
Assemble and tighten the joint as usual. A correctly tightened joint seals low pressure straight away.
4. Let it cure
The adhesive reaches full strength after at least 24 hours. It cures more slowly in the cold.
Frequently asked questions
- How do I take apart a joint made with Loctite?
- Threaded joints made with 511, 542 and 577 can be undone with ordinary tools. If the joint will not come apart, heat the nut or bolt to about 250 °C and dismantle it while hot. A joint made with the 620 retaining compound is heated to about 300 °C.
- Can I use the adhesives on plastic threads?
- Loctite adhesives are generally not recommended for plastics, as thermoplastics may crack under stress. For plastic pipes, use Loctite 55 cord, which seals cold water and compressed air on them.
- Is Loctite suitable for oxygen?
- No. Neither the adhesives nor the Loctite cord are suitable for pure oxygen systems or for sealing chlorine and other strong oxidising substances.
- How much Loctite 55 cord should I wind on?
- It depends on the pipe diameter: on a metal thread ½″ 6 to 8 turns, 1″ 8 to 12 and 2″ 15 to 25 turns. Plastic needs more, 12 to 15 turns for ½″. You do not need to fill the whole thread.
- Why does the adhesive not harden in the bottle?
- An anaerobic adhesive only hardens where air cannot reach it, and only in contact with metal. In the bottle it is in contact with air, so it stays liquid.
A Czech technical data sheet is available for download with every Loctite product. LOCTITE® is a registered trademark of Henkel.
Product sorting
List of products
The manufacturer of the cord is Loctite 55. Package contents are 50 m. Used on fine and coarse threads up to 4".
The manufacturer of the adhesive is Loctite 577. The content is 50 ml. The breakaway torque is 18-22 Nm . Functions for pipe threads up to 3" with medium strength - gases...
The manufacturer of the adhesive is Loctite 542. The content is 10 ml. The breakaway torque is 12-16 Nm. Functions for pipe threads up to 3/4" with medium strength - pneumatics,...
The manufacturer of the cord is Loctite 55. Package contents are 150 m. Used on fine and coarse threads up to 4".
The manufacturer of the adhesive is Loctite 620. The content is 250 ml. The breakaway torque is 28-36 Nm . Functions for pipe threads up to 2" with high strength - gases (DVGW),...
The manufacturer of the adhesive is Loctite 620. The content is 50 ml. The breakaway torque is 28 - 36 Nm . Functions for pipe threads up to 2" with high strength - gases...
The manufacturer of the adhesive is Loctite 577. The content is 250 ml. The breakaway torque is 18-22 Nm . Functions for pipe threads up to 3" with medium strength - gases...
The manufacturer of the adhesive is Loctite 542. The content is 250 ml. The breakaway torque is 12-16 Nm. Functions for pipe threads up to 3/4" with medium strength -...
The manufacturer of the adhesive is Loctite 542. The content is 50 ml. The breakaway torque is 12-16 Nm. Functions for pipe threads up to 3/4" with medium strength - pneumatics,...
The manufacturer of the adhesive is Loctite 511. The content is 250 ml. The breakaway torque is 6-11 Nm. Functions for pipe threads up to 2" with PTFE, suitable for gases (DVGW)...
The manufacturer of the adhesive is Loctite 511. The content is 50 ml. The breakaway torque is 6-11 Nm. Functions for pipe threads up to 2" with PTFE, suitable for gases (DVGW)...