Product details
| Grade | Loctite 55 |
| Strength | Mechanical seal — no cure |
| Colour | White cord |
| Family | Thread sealants |
| Brand | Loctite (Henkel) |
| Stock | Held in Dubai — buy one or bulk |
Pack sizes
Prices on request. Tell us the quantity you need.
Check stockWhat Loctite 55 is for
Not a liquid at all — a coated polyamide cord that you wind onto the thread. There is no cure time, so the joint can be pressurised immediately, and it can still be adjusted up to 45° after tightening without breaking the seal. That last point is why plumbers keep it in the bag: a fitting that ends up facing the wrong way does not have to be stripped and redone.
Key features
- No cure time — pressurise the joint immediately
- Adjustable up to 45° after tightening without losing the seal
- Seals metal and plastic tapered pipe threads to 4in NPT
- Certified to ANSI/NSF Standard 61 for potable water to 82°C (a regional approval)
- Conforms to EN 751-2 class ARp and carries DVGW approval
- Potable water approval to BS 6920; meets WRC and BGA KTW for cold and hot water
- Tested to GASTEC QA AR-214 for hydrogen service (a regional approval)
- Typically used to 149°C
Typical applications
- Water and gas pipes
- Instant sealing
Technical data
Product data
| Technology | White coated cord |
| Chemical type | Polyamide thread with inert proprietary paste |
| Cure | Not applicable — seals mechanically |
| Specific gravity at 25°C | 1.25 |
| Coating weight | 0.54–0.74 g/m |
| Service temperature | Typically used up to 149°C |
| Lubricity, K value (ASTM D5648) | 0.15 on a 3/8 × 16 fastener |
Spool sizes
| 12 m spool | 12.5–14.0 m · 7.0–10.4 g |
| 50 m spool | 50.5–53.5 m · 27.3–39.6 g |
| 100 m spool | 101.0–109.0 m · 54.0–80.7 g |
| 160 m spool | 161.0–169.0 m · 86.4–125.1 g |
How much to use
Henkel's guideline for number of turns by pipe diameter.
| Pipe diameter | Metal — turns | Plastic — turns |
|---|
| ½ in. | 6 to 8 | 12 to 15 |
| ¾ in. | 7 to 9 | 15 to 25 |
| 1 in. | 8 to 12 | 20 to 30 |
| 1½ in. | 10 to 15 | 25 to 35 |
| 2 in. | 15 to 25 | — |
| 2½ in. | 20 to 30 | — |
| 3 in. | 25 to 35 | — |
| 4 in. | 35 to 45 | — |
Pressure and steam
| Pressure resistance (ASTM D1599) | Tested to 69 MPa on 3/8 NPT steel tees and plugs |
| Steam compatibility | 0.17 MPa at 130°C for 1,000 hours on 1.5in NPT |
| EN 751-2 soundness, before and after 45° adjustment | No leaks |
| EN 751-2 gas condensate, hot water, thermal cycling, vibration | No leaks |
How to use it
- Clean the threads with a wire brush before applying.
- Hold the end of the cord against the male nipple, about two threads from the end.
- Wind the cord on in the same direction as the thread helix, starting from the pipe end. Fill the thread grooves without completely masking the thread pitches.
- Do not over-apply. Excess cord gets pushed off as the fitting is assembled and makes full engagement harder.
- Cut to length with the integrated cutter and smooth the loose end onto the thread.
- The joint can be adjusted up to 45° after tightening.
Handling and storage
- Not recommended for pure oxygen or oxygen-rich systems.
- Not a sealant for chlorine or other strong oxidising materials.
- Store unopened and dry, ideally 8°C to 21°C.
Loctite 55 or an anaerobic sealant?
Use 55 where the joint must be usable immediately or may need adjusting — and on plastic threads, which anaerobics do not suit. Use 567 or 577 where you want a cured, locked, chemically resistant seal on metal threads that will not be disturbed.
Always read the current technical and safety data before use —
ask us and we'll send it with your quotation.
