Characteristics and Applications of Anaerobic Adhesives

Anaerobic adhesives are short for anaerobic adhesives. They are single-component sealing adhesives that are made of oxygen on the principle of free radical polymerization. They can be used both for bonding and for sealing. When the coating surface is isolated from air and catalyzed, it can be rapidly polymerized at room temperature and solidified. The composition of anaerobic adhesives is relatively complex, with unsaturated monomers as the main components, and aromatic amines, phenols, aromatic oximes, and peroxides. In recent years, the formulation of foreign anaerobic adhesives has been continuously improved and improved, and it has been favored by the machinery industry.

Since the 1990s, the United States has established a single component anaerobic adhesive standard (ASTM 5363-97), which regulates the manufacture and function of anaerobic adhesives. China also has a chemical industry standard (HG/T 3737-2004).

Anaerobic adhesive characteristics and applications

(1) Most are haplotypes, with a wide range of viscosity changes, many varieties, and ease of selection.
(2) It is not necessary to weigh, mix, and mix glue. It is extremely easy to use and easy to automate.
(3) Curing at room temperature, high speed, high strength, energy saving, low shrinkage, and good sealing. Removable after curing.
(4) Excellent performance, good heat resistance, pressure resistance, low temperature resistance, chemical resistance, impact resistance, shock absorption, antisepsis, anti-fog and other properties.
(5) Adhesive overflow adhesive is not cured and easy to remove.
(6) Solvent-free, low toxicity, little harm, no pollution.
(7) Widely used, sealing, locking, holding, bonding, plugging, etc. can be used.
(8) Stable storage, glue storage period is generally three years.

Anaerobic adhesives have unique anaerobic adhesive properties and can be used for locking, sealing, holding, bonding, and plugging. Anaerobic adhesives have become an indispensable liquid tool for the machinery industry. In aerospace, military, automotive, machinery, electronics, electrical and other industries have a very wide range of applications.

(1) Lock the lock. Metal screws are easily loosened or off-line due to shock and vibration. The traditional mechanical locking methods are not ideal, and chemical locking methods are inexpensive and effective. If the screw is assembled after the anaerobic adhesive is applied to the rabbit, a strong plastic film is formed in the thread gap after curing, so that the screw locking will not loosen. There are now pre-coated (B-204) anaerobic adhesives that are pre-coated on screws and placed for use (valid for four years). As long as the screws are screwed in, the desired anti-loosening effect can be achieved.

(2) Seal leakproof. Any plane can not be completely close contact, need to leak seal, the traditional method is to use rubber, asbestos, metal gaskets, but will soon leak due to aging or corrosion. The use of anaerobic adhesives instead of solid gaskets, after curing, can achieve close contact, making the seal more durable. Anaerobic adhesives are used for the sealing of threaded pipe joints and threaded plugs, the sealing of flange mating surfaces, and the sealing of the mechanical box joint surfaces, all of which have good leakage prevention effects.

(3) Hold positioning. Cylindrical row components, such as bearings and shafts, pulleys and shafts, gears and shafts, bearing and seat holes, bushings and holes, etc., hole shaft assembly accessories, previously without exception, the use of hot sleeve, cold pressure and other size interference method re-assembly , supplemented by keys and pins. This fixing method requires strict machining accuracy, and due to the difference in thermal expansion coefficients, wear and corrosion occur, and loosening is easily generated. The use of anaerobic adhesive can fill the fit gap, solid and durable after curing, stable and reliable. The method of holding anaerobic adhesive reduces the processing precision, facilitates the assembly operation, improves the production efficiency, and the energy consumption and processing costs of the delivery.

Fill plugging. For microporous castings, die castings, powder metallurgy, and welded parts, a low-viscosity anaerobic adhesive (B-290) can be applied to the defect so that the glue penetrates into the micropores and is isolated at room temperature. In the case of oxygen, the cure can be completed, filling the hole and sealing. If vacuum infiltration is used, the success rate is higher and it has become a new technology in the foundry industry.