Anaerobic sealant: pros and cons

The term “anaerobic” is borrowed from the microbiology building industry. It denotes a class of microorganisms that do not need oxygen for their vital activity. Accordingly, the essence of the work of the sealant can also be characterized - it does not need air for polymerization and solidification, because all these processes occur without oxygen.

There are different types of sealant for different degrees of complexity.

They differ from each other by several criteria:

• viscosity;
• fluidity;
• degree of penetration into the surface.

Based on the degree of strength all the compositions can be divided into:

1. Standard - used for materials that are not exposed to vibration in the absence of the need for frequent dismantling or disassembly of elements. Such sealants are much easier to remove without using special tools. Value in the range of 4 - 9 Nm.
2. Average - used for compounds that are exposed to high atmospheric pressure or strong vibration in service and repair work. Removal of such a substance requires special tools or direct heating with fire. The value is 15 - 22 Nm.
3. Elevated - mainly used for fixing threaded connections that will not dismantle or disconnect for several years. This degree is the most durable and can withstand very powerful vibration and pressure. In order to disconnect such a connection, a force of at least 55 - 60 Nm is required.

The smaller the space between the elements to be joined, the higher the penetrating property of the adhesive should be. Accordingly, the consistency of the composition and its viscosity should be minimal.

The color of the sealant indicates the scope of its use and some properties.composition. At the moment, you can buy glue blue, green, red, orange and yellow.

Also, the compositions are divided into the following groups:

• Used in communications of heating systems to seal pipe elements. They differ in that they tolerate high temperatures and hot water.
• Hermetic compounds, insensitive to the influence of substances with aggressive environment. Maintain a temperature in the range of 60 - 150 ° C.
• Fast-hardening adhesive, characterized by high adhesive properties.

All the positive qualities of anaerobic sealant are achieved through a chemical reaction between the substances in its composition. It consists of oligomers or polymers from the group of acrylics (giving the necessary consistency and viscosity) + substance initiation (providing accelerated polymerization).

Falling on a metal surface, the mixture fills even the smallest and smallest cracks, and then, quickly setting, forms a kind of rubber layer. Under this layer with the help of radicals, a polymerization process takes place. The sealant hardens gradually, starting from the moment when oxygen stops flowing to the seam.One of the main advantages of such a sealant is its high resistance to vibration, which prevents the threads from loosening fixation.

Using years of experience in the construction industry, manufacturers have managed to create a material that has several undeniable advantages:

• reliable fixation of plumbing pipes;
• high strength and wear resistance;
• resistance to vibrational vibrations, which often serve as a fundamental cause in the destruction of communications;
• safe in contact with drinking water;
• after the glue hardens, it can no longer be dissolved in water;

• compound materials of different structure;
• ease of operation - even a person will cope with the application without any experience;
• resistance to high atmospheric pressure - no more than 50 atmospheres;
• immunity to aggressive substances, solvents, paints and oils;
• protects the metal from corrosive changes;
• long service life, which even in the worst conditions lasts up to 4 years;
• high-temperature composition, which is not destroyed even at a temperature of + 300 ° C.

However, not everything is perfect here. Having a wide range of advantages, the sealant is still not deprived of some disadvantages:

• The communications recorded by this train are very difficult to disconnect or dismantle.Sometimes, in order to remove the sealant, it is necessary to subject it to heat by direct fire. In contrast, an ordinary fum-tape or tow will be cleaned much easier.
• High cost price. Quite often, consumers refuse to buy anaerobic sealant due to its high price. But if we consider the sufficient profitability of the composition, then the spent money will be justified.
• Sealant from different manufacturers will not be identical, their composition will vary in the volume of the active component.

It is necessary to work with sealant strictly following the instructions. Do not handle wet compounds, as the desired effect can not be achieved. Therefore, it is important to completely dry the work surface and remove all moisture. There is also a limitation of the diameter of the processed communications - the pipes must be no more than 10 cm in diameter, the wider parts are more difficult to process and dry longer.

Oxygen-free adhesives-sealants are widely used in various fields:

• For locking and sealing threads, replacing various mechanical devices.At the moment, the composition is the easiest and most reliable way to strengthen the threaded connections to the effects of shaking, shock loads and vibration. Due to its semi-liquid consistency, it completely fills the entire space and is able to evenly distribute the load on the coils, preventing leakage of gaseous substances or any liquid.
• For blocking and fixing sliding joints. This includes all metal joints, for example, bushings and bearings. Oxygen-free gels allow you to plant parts with a gap, without heavy deforming stress, but at the same time maintaining shear strength.

• Strengthening of various pipe joints: flanged and threaded. Unlike mechanical devices, which over time are destroyed by vibration and stress, decompose in an aggressive environment and pollute the environment, the sealant can remain in its original state for a long time and firmly fix the pipe elements.
• Impregnation of porous material, welded seams and extruded products. The gel perfectly removes small pores, cracks and other defects in the field of welding, casting and pressing.

As mentioned earlier, the anaerobic sealant hardens very quickly. However, despite this, working with him is easy and even a beginner can handle it. To achieve the desired effect, you just need to follow the instructions on how to use the tool, because the sealant is sold completely ready for use and it does not need to be pre-prepared or mixed with solvents. It is better to completely clean the working surface in advance, and after degreasing it will enhance the reaction and the composition will get much better.

Instructions for use:

• We take the container with the composition and thoroughly shake, thereby mixing the contents.
• Open the container and apply the tool around the connection perimeter.
• Next, completely twist the elements, which were applied sealant.
• The excess must be removed immediately, without waiting for the composition to dry.
• We give the sealant to dry, leaving it for about half an hour (the gel dries differently, depends on the diameter of the compound being processed and the temperature in the room) and then we check it under a pressure of 10 atmospheres. In case the ambient temperature does not reach + 15 ° C, the sealant must be heated.If, after checking, there are no leaks, then after a day, it is possible to test for operation under a pressure of 40 atmospheres.

To ensure maximum bonding, the composition can be applied to both surfaces, that is, inside and outside. But this should be done carefully, so as not to apply too much sealing agent. If plastic pipes are processed, they must be treated with a special activating agent before work. Quite often, a brush is supplied with the container, which greatly simplifies the application process.

Anaerobic sealant is produced and produced by quite a lot of companies, so some difficulties may arise when buying from a consumer. Rating of some of the most common and popular brands of anaerobic sealant:

• Loctite The company produces both liquid sealants and sealing threads. They prevent the leakage of gas or liquid and significantly increase the strength of the connection. The price of the compositions of this brand depends on the area in which they are used and what characteristics the gel has. For example, the universal sealant Loctite 577 costs 1760 rubles for 50 ml, while Loctite 542, designed for small threads, costs slightly more than 1,800 rubles for the same volume.

• "Clamp number 3" - medium strength anaerobic sealant with a homogeneous thixotropic consistency and blue color without any inclusions. Glue withstands such substances as water, oil derivatives, gas, hydraulic fluid, ethylene glycol compounds, alkaline and acid solutions. It is used in work with any metals, regardless of the presence of a protective coating. Examples of application: valve mechanisms, covers, mounted equipment for internal combustion engines, sealing of the necks, assembly of utilities for housing and public utilities (heating, gas, water supply), plumbing. It tolerates high pressure and vibration. The cost is 300 rubles. Analogue from the company Loctite at number 243.

• SantehMaster. The domestic company produces red and blue composition in the form of a gel, complete with which is a brush. It is used mainly in work with gas and plumbing connections up to 5 cm. In a room with room temperature (18-19 ° C), the collected pipeline can be tested already 15 minutes after assembly under a pressure of 0.5 atmospheres. After 60 minutes, it can be increased to 10 atmospheres, and in a day to 40.The sealant is not resistant to antifreeze, gasoline, alcohol, high pressure and temperature. A bottle with about 15 ml of material will cost at least 150-200 rubles.

• "Siseal" - sealant from the company Manta Ecologica. It is also most often used in fortifications of engineering systems: water, gas and water. Suppose in working with drinking water. Polymerization time also depends on the air temperature in the room. It is a medium-strength adhesive, but the product with the prefix "S" (red) is already a strong sealant, which requires warming up with a hair dryer or a burner for disassembly. When disassembling does not require additional heating. In general, all other characteristics are standard. The cost of a bottle with 100 ml is about 800 rubles.

• Permatex. The sealants of this company are designed mostly for the flange, ensuring the filling of the smallest roughness and absolute contact between the contacting surfaces. After bolting, the composition will force out all the air and turn into plastic with high strength. As mentioned above, glue is most often used for flange connections of the gearbox, sediments in the cylinder block and small gaps between the metal elements are sealed.The use of the mixture will increase the rate of torsion, replace the additional tightening of fasteners, protect against corrosion, make further disassembly more simple. It will evenly distribute the load over the entire surface area and make the transfer of forces between parts more accurate, protect against dirt and simplify the installation of gaskets on vertical surfaces. A bottle of 50 ml will cost the consumer about 700 rubles.

• "Quickseal 728" - medium-strength oxygen-free gel glue. It is used for fastening connections of hydraulic and pneumatic power mechanisms. The sealing compound seals the threads of metal parts, protecting them from mechanical damage and vibration waves. When removed, requires heating. Polymerization features: glue hardening occurs in the temperature range from + 20-25 ° C, and the lower the temperature in the room, the slower the sealant will harden. The material is not used for metal-plastic elements, oxygen equipment and systems or compounds with strong oxidation. Designed exclusively for standard metal construction. Before work the surface needs to be cleared and degreased.The cost of a bottle is 800 rubles.

If it becomes necessary to separate the fixed parts, the sealant can be removed immediately after work or some time after hardening. For dismantling you will need a wrench and a building dryer in case the composition is durable.

Removal Instructions:

• turn on the building dryer and direct the hot air stream to the seam;
• we wait until the mass begins to crumble and after we remove it with an ordinary rag;
• wrench and disassemble the connection.

There is no need to completely clean off the remnants, a new layer can be applied directly over the old one.

When choosing a sealant, consider the following:

• connection operating conditions;
• any features of the thread;
• at what temperature the gel will be used;
• what are the requirements for the strength of the future connection;
• how often it will be necessary to disassemble the connections;
• What material is the thread made of?

See the following video for the pros and cons of anaerobic sealant.