- Clean and easy to apply
- Resists vibration and impact
- Excellent performance on a variety of metals
- Provides uniform assembly torque to prevent fretting corrosion
- Reduces inventory costs
The main criteria for selecting the right threadlocker from Loctite’s extensive product range are: the material (plastic or metal), the diameter and thread length of the screw or bolt used, and its strength grade. Many Loctite products are universally compatible with a wide range of thread sizes. Low strength: Can be removed with standard hand tools. Suitable for adjustable, standardized screws, measuring instruments, etc. (thread size: ≤M80) Medium strength: Can be removed with hand tools, but will be more difficult to remove. Suitable for machine tools, presses, pumps, compressors, assembly bolts, gearboxes (thread size: ≤M80) High strength: Very difficult to remove with standard hand tools; heat may be required for removal. Suitable for permanent assemblies such as heavy transport, wall studs, engines, ejector pumps, etc. (thread size: ≤M80)
Anaerobic adhesive bottles are specially developed oxygen-permeable polyethylene bottles that allow air to pass through the bottle wall, thereby maintaining the stability of the liquid product. For the purpose of adhesive stability, the bottle cannot be filled to the brim. A 50ml product actually contains 50ml of product in a larger packaging bottle.
No solvent can penetrate the joints and break down the threadlocker. In this case, removal with hand tools at room temperature is possible. If this is not possible, the components must be separated at elevated temperatures (232°C-315°C). These products are thermoset plastics in their cured state and soften at higher temperatures. Therefore, removal requires elevated temperatures. Avoid disassembly while the product is cool, as its strength will recover upon cooling. After disassembly, solvents such as methyl ethyl ketone and methylene chloride can be used to clean any residue.
Yes, you can. Traditionally, we recommend using retaining compounds such as Loctite 609 or Loctite 603, but threadlockers share the same basic chemistry and can be used as an alternative in many situations. In fact, the threadlocker Loctite 271 has been used for stud and bearing installation for many years. Conversely, you can use retaining compounds to lock threads, as long as you recognize that most will permanently lock the threads.
For thinner grades like Loctite 609 and 603, the best fit diameter is 0.001-0.003′. For thicker grades like Loctite 620 and 638, the best fit diameter is 0.002-0.004′.
Anaerobic adhesives are generally not suitable for most plastics. Anaerobic adhesives can cause stress cracking in some plastics, including many thermoplastics like ABS and polycarbonate. If used between metals in close proximity to the plastic, excess liquid product or vapor may affect the plastic. For compatible plastics like acetal, anaerobic adhesives are not the best product for achieving effective locking and sealing. Cyanoacrylate adhesives are generally recommended when other application parameters are met.
Yes, you can heat cure anaerobic adhesives to achieve a full cure faster. Typically, these products can be cured by heating at 250°F (125°C) for about an hour, or at a lower temperature, such as 150°F (66°C), for three hours. However, as a trade-off, this may reduce some of the ultimate strength. Whenever you accelerate the crosslinking of a polymer, you reduce the ultimate strength. Please conduct careful testing to determine suitability.
When both parts are classified as “inactive” metals, we recommend using primers such as Loctite 7649 and 7471 before most anaerobic adhesives. These metals lack iron or copper content and, therefore, lack the “active” metal ions necessary to fully cure the product within 24 hours. Examples of these metals include plated parts, stainless steel, galvanized steel, and anodized aluminum. On the other hand, if both parts, or at least one, are “active” metals such as ordinary steel, brass, bronze, copper, or iron, no primer is required, and full cure can typically be achieved within 24 hours at room temperature.
For through-hole applications, such as nut and bolt combinations, simply apply threadlocker to three or four threads on the bolt and around the outside diameter, and assembly is complete. For blind-hole applications, such as bolts entering enclosed housings, it’s crucial to apply threadlocker to both the male and female threads. If applied only to the male threads and then tightened, air pressure can squeeze out most of the product during assembly. This results in incomplete coverage and partial cure, leading to premature failure.
Generally speaking, threadlockers will support the growth of pre-existing fungi, but will not promote their growth. Many threadlockers meet military specifications that state (Mil-S-22473E, Mil-S-46163A) that the polymeric compound will not support the growth of fungi when tested according to military standard specifications.
There are no long-term studies on the compatibility of anaerobic adhesives with various elastomers. However, there is general agreement that liquid anaerobic adhesives may cause adverse effects on certain elastomers in the form of swelling, cracking, and weight changes after prolonged contact with the latter. Customers should carefully test their products for compatibility. Some Loctite dispensing equipment is designed specifically for use with fluoroelastomer O-rings and seals because fluoroelastomer is considered suitable for extended use with anaerobic adhesives. Once the anaerobic adhesive has cured, compatibility issues should not arise between the rubber component and the very inert cured plastic film anaerobic adhesive.
Yes. Anaerobic adhesives can be used on oil-impregnated parts. Simply wipe the parts clean before applying the product. More oil-resistant grades like Loctite 603 and 243 are good choices because they offer better resistance to cutting oils, allowing them to cure well and provide an effective seal after curing.
Glue stick products are similar, but not identical. Their chemistry and functionality are the same, but with some significant differences. Glue stick products are not recommended for blind hole applications. Blind hole applications require applying the product to the male and female threads, which is difficult due to the stick formulation. Glue stick products produce strength values that differ somewhat from their liquid counterparts. Refer to the TDS for specific data. Additionally, unlike their liquid counterparts, glue stick products have not been tested to any military standards.
Both are anaerobic flange sealants designed for rigid machined flanges. They are similar products, with one key difference being that Loctite 518 performs better on aluminum flanges. Therefore, Loctite 518 can replace Loctite 515 in most applications. However, Loctite 518 is generally a faster-setting anaerobic adhesive and may cure too quickly on highly reactive metals like brass. In such cases, Loctite 515 may be a better choice.
Yes—torque-related properties for LOCTITE anaerobic threadlockers have been measured, but a single universal “torque coefficient (K / nut factor)” value is usually not published as a fixed product parameter, because it depends heavily on the fastener system (material/finish, lubrication/oil, thread class, washers, speed, curing state, etc.).
Loctite thread sealants seal and secure plugs, pipes, and fittings. They fill the gaps between threaded metal parts and then harden to prevent and stop leaks. Loctite offers a wide variety of pipe thread sealants, specifically developed for the different properties of materials.
Anaerobic flat sealants are self-forming liquid gaskets that can completely fill the gaps between flange surfaces, thereby preventing gas or liquid leakage and assembly interface corrosion at the interfaces of composite machine parts or pipelines.
Flat sealants can be used with many different types of materials, including various metals, wood, plastics, rubber, ceramics, glass, and even concrete. The type of sealant selected for a specific application depends on the materials being sealed, the environmental conditions, temperature, and operating pressure within the system.
- 0-0.15mm: Low viscosity retaining compound (125 to 2,000 mPa•s);
- 0.15mm: High viscosity retaining compound (2,000 mPa•s)
There are several ways to increase the toughness of cyanoacrylates, but the most popular method is to use rubber or anhydride toughening agents. Toughening agents are designed to absorb and distribute the shock and pressure applied to the adhesive bondline, resulting in a stronger bond. Toughened cyanoacrylates: If subjected to shock loads, toughened cyanoacrylates can prevent cracking from propagating to the bondline by absorbing the force. Additionally, they offer enhanced thermal performance and resistance to metal bonding in humid environments.
Because of its high water content, instant adhesive quickly bonds to skin. A simple method is to run a pen or pencil across the bond line, applying peeling force to the adhesive and separating the skin between your fingers. You can also try warm water and soap.
- Instant adhesive primers are pre-applied solvent-based products designed to promote adhesion (not cure speed) on “inactive” surfaces, making them suitable for bonding with cyanoacrylate adhesives. Before applying the adhesive, the solvent-based primer must be allowed to evaporate and dry (typically within one minute). Primers are not recommended for all substrates; therefore, consult the product TDS for detailed data.
- For optimal results with any Loctite instant adhesive, ensure the surface is clean and oil-free. Loctite 770 is particularly well-suited for polyolefin plastics such as polypropylene (PP) and polyethylene (PE). When mixing multiple materials, primers should only be applied to difficult-to-bond substrates.
Instant adhesive accelerators are solvent-based products that can be applied pre- or post-applied to increase the cure speed and/or improve the gap-filling ability of cyanoacrylate adhesives. They can also be applied post-application to cure cyanoacrylates that have squeezed out of bond lines or to hold items like wires in place. They are particularly useful in very cold and dry environments during the winter.
When using instant adhesives to bond glass, initial strength is high but decreases significantly over time. Due to the fundamental properties of glass, curing occurs very quickly, potentially generating high molecular-level stresses in the adhesive layer directly adjacent to the glass. Over time, these high stresses can cause chemical and physical degradation of the cured polymer surrounding the adhesive layer due to contraction and expansion of the joint, temperature fluctuations, and hydrolytic erosion. Consequently, when used to bond glass substrates, permanent bonds cannot be achieved at the joint.
Stress is more evenly distributed across the entire bond surface, which has a very positive impact on the static and dynamic strength achieved. Welding and riveting can lead to local stress peaks, while adhesive bonding allows for a more uniform distribution and absorption of stress loads. The surface and texture of the bonded materials are not altered, whereas welding temperatures can alter the texture and, therefore, the mechanical properties of the material. Furthermore, welding, riveting, and fastening all affect the visual appearance of the component. Weight reduction: Adhesives are particularly popular for lightweight construction, especially when thin-walled components (wall thickness < 0.5 mm) need to be joined. Sealing and unsealing adhesives can also act as sealants, preventing pressure or liquid loss, blocking condensation penetration, and providing corrosion protection. Henkel’s liquid sealants offer great flexibility to meet the requirements of most applications, joining dissimilar materials and reducing the risk of corrosion. The adhesive forms an insulating film to prevent contact corrosion when joining different types of metal. It can also serve as an insulator and thermal insulator.
- Eliminate or significantly reduce the use of expensive mechanical fastening methods
- Improved appearance compared to mechanical fasteners
- Extremely fast processing speed
- Reduced labor costs
- Fills large gaps between parts
• User-friendly packaging
It’s not necessary to over-apply accelerator, as it can inhibit cure and reduce ultimate bond strength. This can significantly shorten the setting time and significantly reduce the adhesive’s resistance to moisture and aging. Furthermore, for tight-fitting (almost zero-gap) applications, applying a small amount of accelerator is more effective. Since each application is different, it’s recommended to test the product’s suitability before use.