Why are some bolts in the design of industrial structural joints pre-coated with drop-resistant anti-loosening adhesive?

Why are some bolts in the design of industrial structural joints pre-coated with drop-resistant anti-loosening adhesive?

The main reasons for screw loosening are: the operation of parts, vibration, impact, etc., caused by the loss of preload between the working objects of the connected parts connected, the external load, especially the transverse load, exceeds the friction generated by the preload of the bolt, resulting in mutual sliding between the connected parts, thus causing loosening. The factors affecting the loosening of the screws are hardness, material, surface treatment, lubrication, and bolt threads.

The purpose of the bolt coating

One type of fastener glue is an anti-loosening solution. Currently, glue is used for anti-loosening and sealing. There are mainly two kinds of physical glue.

Screw drop-resistant adhesive is a product that can make screws stronger, safer, and more reliable. It is composed of a group of chemical substances can effectively prevent screws from loosening or falling off, but it also has a certain cushioning and anti-corrosion function. Bolt gluing is an essential fixing technique whose primary function is to enhance the tightening force of bolts and prevent loosening. Typically, the gluing process is achieved by applying a specific coating to the surface of the bolt. The types and formulations of coatings are designed according to different application scenarios, and their curing time varies according to the temperature, humidity, pressure, and other factors of the application environment.

1. Anti-loosening function, which can resist any long-time constant vibration without screws coming loose, is the best anti-loosening technology at present. The bolt will appear loose with the growth of mechanical equipment or vibration, impact, and other external forces. Bolt coating can enhance its tightening force to avoid the loosening of bolts, thus ensuring the safety and stable operation of the equipment.

2. It can be reused without affecting the fixed anti-loosening function.

3. It has excellent chemical resistance because its chemical composition is a multi-compound polyamide resin; inert, general solvents (ether, ketone, gasoline, diesel, acid, alkali, etc.) do not react.

4. Temperature resistance: General products can be stored at minus 40 degrees to 150 degrees Celsius, and their performance is stable.

5. Enhance the fastening force: the coating can enhance the bolt fastening force, improve the stability and efficiency of the equipment, and reduce the risk of failure and damage.

6. Improve the sealing: glue can fill the microscopic gap between the bolt and the material to be fixed, increase the sealing performance of the fastening part, and prevent pollution and penetration of the external environment.

Application areas of pre-coated drop-resistant screw adhesive

Drop-resistant screw adhesive is a unique engineering resin coated on drop-resistant screws, which has the advantage of very high chemical stability, acid and alkali resistance, and other solvents, and does not oxidize and corrode the metal, so the screws will not rust, the phenomenon of flaking of the electroplating film, and contributes to the lightweight, weather resistance and high quality of the product requirements.

In the automobile, machinery, electronics, construction, and other fields, screws are indispensable and essential parts. And screw's fall-resistant adhesive also came into being as a result. It can be widely used in manufacturing machinery, automobiles, electronic products, construction engineering, aerospace, and other fields to make the screws stronger, safer, and more reliable.

Our familiar Volkswagen uses glue outside the anti-loosening way more, such as the use of the bolt head under the form of a toothed washer; this kind of toothed washer is also a patented nature of the washer or the bolt head under the toothed this kind of, or the nut support surface with the toothed type of anti-loosening way in the Volkswagen car design is more common. There are also other practices, such as spherical bolt design, in the steering knuckle and bearing connection position, which is to use this unique bolt head design, which is also this position, and other companies with some different design forms.

This kind of washer and our automobile standard washer, bolt with teeth type is different; this so-called with teeth type is the arc of the radial tooth shape; there is no sharp acute angle, and our automobile standard parts with teeth bolt type with more sharp teeth. You may wonder whether this type is less effective in preventing loosening than the type of automobile standard parts. The actual transverse vibration test results show that this type of anti-loosening effect is perfect; transverse vibration after 2000 times did not appear below 80% of the initial preload.

Volkswagen adopts this particular type of locking design relatively more. General Motors adopts the anti-loosening form of relatively more rubberized anti-loosening; for example, General Motors steering knuckle and bearing joints may have adopted the rubberized bolts.

As far as which parts need to adopt the form of anti-loosening?

Automobile threaded subconnection firm or not directly affects the car's use. In the car design of the corresponding anti-loosening measures, commonly used friction anti-loosening spring pads, preload anti-loosening or special self-locking threads, etc.; mechanical methods of anti-loosening cotter pins, locking pieces, anti-loosening of fuses, and so on.

Threaded joints commonly use anti-loosening methods, including friction, mechanical, and permanent anti-loosening. Among them, the use of friction anti-loosening methods such as double nuts, spring washers, and self-locking nuts; the use of mechanical anti-loosening methods such as cotter pins and slotted nuts, stopping gaskets, round nuts, with finned gaskets and tandem steel wire, etc.; permanent anti-loosening methods such as riveting, punching points and bonding.

The standard requirements of the screw drop-resistant adhesive

Drop-resistant adhesive, also known as screw fixing agent or anaerobic adhesive, is mainly used in electrical appliances, electronics, aviation machinery, automotive industry; drop-resistant adhesive and screws of the "intimate relationship" is manifested wherever there are screws that will see it.

If it is a good locking screw will point it to the mother of screws. Let it slowly cure. On the one hand, the screw will not fall off in the operation. On the other hand, there is rust prevention. In the future, if you want to repair. Just increase the force can be removed. You can also put the glue on the screws. Then only lock on. This effect will be better. But the work will be a little more trouble. Generally, most of the product is done. Finally, fix the glue to each screw. Let it cure naturally for about 10 minutes after normal dispensing. The surface is not stained and fully healed for about 6-8 hours.

Screws drop resistance principle: is to screw teeth on the processing of special engineering plastic; you can make the screw nut in the locking process because the engineering plastic is pressed and squeezed to produce a strong friction torsion and reaction force, resulting in a complete tooth section of the contact, to provide the absolute resistance to vibration, so that the general screws into a permanent strong drop-resistant screw, a complete solution to the problem of screws loosening. The standard screws fall-resistant adhesive mainly includes the following aspects:

1. Durability requirements: the durability requirements of the screw drop resistance adhesive mean that after some time after the use of screws, the drop adhesive still has a good effect and will not appear loose or fall off.

2. The working temperature range: screw drop resistance adhesive in the working temperature range can not appear embrittlement, rupture, and so on to ensure the service life of the screws and the safety of the machine.

3. The strength value: screw drop resistance adhesive strength value should be large enough to ensure that the screws are subject to extreme conditions of tension and vibration drop rubber will not rupture or fall off.

A design selection of the principle is: for some bolts, longer bolt connection, generally as long as the design of sufficient preload can be used without additional types of anti-loosening; however, for some short bolts, even if the preload design is adequate, but also need to consider adding a certain amount of additional anti-loosening measures. This is mainly because a short bolt will appear with more excellent torque attenuation, and the critical sliding amount of short bolts will be smaller; in the enormous load and vibration, it is relatively easy to rotational loosening and non-rotational loosening double loosening.

How to choose the suitable screw adhesive?

Choosing the right screw fall-resistant adhesive needs to be based on the specific needs of the user. First of all, it is necessary to consider factors such as the size of the screw, the type, and the required strength value. Also, we need to consider the nut material, application areas, working environment, and other factors. In the selection of screws fall-resistant adhesive, you need to combine the above factors for consideration, selected for their use of screws fall-resistant adhesive.

The impact of bolt gluing on the operation of the equipment may be more than the above three points, but also the following points:

1. Improper gluing will lead to problems: As the bolt gluing process is related to the type of coating, curing time, and other factors, if the operation is not appropriate, it may lead to poor gluing quality and even affect the regular operation of the equipment. It should be done as soon as possible under the guidance of professionals.

2. Gluing will increase the difficulty of disassembly: While gluing can enhance the fastening force, it also increases the difficulty of disassembling the bolts, which requires more time and effort.

3. Gluing may affect the performance of the material: Different coatings have different chemical compositions and properties. If the wrong coating is chosen or the coating is too large or too small, it may damage the material's surface and affect its performance. In addition, if the coating glue penetrates the surface and interior of the material, it may also affect the performance and life of the material.

Steps for the correct use of screw-resistant adhesive

1. Cleaning the thread surface: before applying the adhesive layer, the thread surface needs to be cleaned first to remove the oil, dirt, and other impurities on the surface. Clean the screws and nuts to ensure that there is no oil, dust and other debris.

2. Glue: evenly coated with an adhesive coating agent in the cleaned thread surface, and then the nut or bolt can be tightened. Apply the appropriate amount of screw fall-resistant adhesive on the threads of the screws.

3. Curing: After the application is completed, it needs to be curbed for some time to achieve the best results, and generally, it needs to wait 24 hours. Tighten the nut to screw drop-resistant adhesive curing; you can complete the screw connection.

Other car companies use the coating method more. A significant reason is that the coating of anti-loosening can basically use the existing bolt design without the need for greater changes. After the coating of glue, the anti-loosening effect can achieve a relatively ideal level.

Advantages of applying glue to bolts

1. Good anti-loosening: The friction between the bolt and the nut coated with the adhesive layer increases to achieve anti-loosening, as do the static and kinetic friction.

2. Anti-corrosion: Bolt coating can form a protective film in the external gas or liquid environment, protecting the bolts' surface and improving their service life.

3. Noise elimination: the buffer damping effect of the bolt coating can reduce the noise generated by the bolt during operation.

Bolt coating prevents the loosening and corrosion of the machine or equipment and improves its service life and efficiency. In the construction process, you must operate strictly with the requirements to ensure the gluing effect is optimized. If you would like to know more about the professional knowledge of resistant glue screws, you can contact our experienced technical sales team. Email:adelajonly@gmail.com,www.juxinfasteners.com.