1. Superior followability

Due to the fully closed structure of the bellows seal itself, the dynamic and static rings and the dynamic seal ring of the shaft sleeve (or shaft) that are necessary in the ordinary spring seal are eliminated in structure, so that the elastic rate of the bellows itself is fully utilized to form a specific pressure. (The ordinary seal, due to the existence of the sealing ring, needs to consume part of the balance force when the moving ring shaft sleeve is relatively displaced. The friction between the sealing ring and the shaft sleeve (or shaft) makes it in place, and the size of the balance force is affected by the seal. The processing dimensional accuracy of the ring and the limitation of heat treatment show its superior followability. During the use process, ordinary mechanical seals often cause the pump body to be evacuated due to various reasons such as device fluctuations or operating processes. At this time, the existence of the moving ring seal ring After the end face is opened, it cannot be reset in time, resulting in the leakage of the mechanical seal, and the bellows mechanical seal eliminates the way of this seal failure in structure. It is hardly affected by the pump body evacuation, showing its good compensation and performance. Light hydrocarbon pumps that are easy to evacuate, vacuum tower bottom pumps and other pumps have outstanding performance. This feature is an important reason for the popularization of bellows seals.

2. High temperature resistance

Since the bellows seal cancels the influence of the moving ring seal in the ordinary spring seal, the applicable medium and temperature are greatly expanded. Usually, the material of the moving ring seal of the ordinary mechanical seal is mostly made of organic compounds such as PTFE rubber. These organic compounds In some media, the compound will react chemically with the whole body of the medium. At low temperature and high temperature, it will change its physical properties and cause hardening to make the seal fail. The bellows seal is not limited by the above factors, and is usually suitable for benzene, Ketones, olefins, alkanes, general oils, acids, alkali salts and many other media, the temperature range can also be from -250 degrees to 450 degrees. Of course, this also requires strict selection of metal bellows, welding and thermal repair.

3. Balance

Compared with ordinary mechanical seals, the bellows seal does not need to be processed on the shaft sleeve, and the balance diameter can be established by itself. When the bellows is in a balanced state (usually partially balanced), the size parameters of the inner and outer diameters of the bellows can be adjusted to achieve Ideally, bellows mechanical seals are generally balanced in application.

4. Fewer leakage points

The sealing points of the moving ring and the static ring are all metal (non-metallic) gaskets that are sealed and connected by bolting, so it is difficult to find leakage. In fact, the leakage of the bellows mechanical seal is only the dynamic sealing point of the friction pair. The probability is greatly reduced, and there are three main leakage channels of ordinary mechanical seals: the dynamic ring seal, the static ring seal and the end face of the friction pair. In this leakage channel, the sealing leakage caused by the failure of the auxiliary sealing ring of the dynamic and static rings accounts for 40% of the total leakage.

5. Earthquake resistance and high speed

The bellows seal cancels the moving ring sealing ring and greatly reduces the vibration of the moving ring caused by the transmission of the moving ring sealing ring caused by the vibration of the pump body or the shaft vibration, so that the moving ring is not greatly affected. Floatability.

When the bellows is designed as a static structure with a damping device, the damper can effectively prevent the resonance with the shaft and the pump body under the condition of high linear speed, so the applicable linear speed is greatly improved. The speed can reach 100M/S.

6. can reduce the spring specific pressure

In the use of ordinary mechanical seals, the spring specific pressure is generally designed to be 0.15MPa-0.25MPa, while the spring specific pressure of the bellows seal is generally designed to be between 0.05-0.15MPa. When the bellows seal is a static structure, the spring specific pressure is obvious. too small. Therefore, the frictional heat generated by the specific pressure of the spring is reduced, and the temperature of the end face is reduced, thereby reducing the wear amount of the end face during friction, that is, reducing the mechanical power consumption, improving the sealing performance and prolonging the service life of the sealing.

7. It can transmit torque itself. In the operation of ordinary mechanical seals, it is necessary to add a structure to transmit the seal. There are various structural forms, such as fork, pin, screw and tightening to transmit torque performance. Generally, no additional transmission is required. It can be used normally after twisting, the structure is simplified, the failure caused by the failure of the transmission structure is avoided, and the reliability of the mechanical seal is improved. structure, increase its anti-torque ability and stability, and play an auxiliary role, which is widely used in high pressure and high speed sealing.

8. Design a certain structure to reduce the seal failure caused by water scaling: in many areas, due to poor water quality, the scaling index is high, and there is no specific softened water treatment device, the moving ring in the ordinary machine seal The failure of auxiliary sealing ring due to water scaling has been a long-standing problem.

The bellows seal is designed as an external cooling or static structure, which can effectively prevent its scaling. If the structural design is unreasonable or improperly applied, the bellows seal is also prone to scaling, resulting in seal failure. Therefore, it is recommended to use bellows. Using cooling water as cooling water as water, in this way, the working environment of the bellows seal will be greatly improved and the service life will be extended.

9. Remove the sealing oil and save costs. In ordinary mechanical seals for pumps with high temperature and impurities, due to the limitation of the operating temperature of various auxiliary sealing rings and friction pairs, external flushing oil (sealing oil) is often injected around the friction pairs. , to lubricate and reduce the temperature of the sealing chamber to establish an adaptable environment suitable for the work of each component. However, a lot of money is wasted due to oil sealing flushing. Selecting an appropriate amount of bellows seal can save a lot of oil sealing money without sealing oil.

10. Design a certain structure to reduce the seal failure caused by water scaling: in many areas, due to poor water quality, the scaling index is high, and there is no specific softened water treatment device. The failure of auxiliary sealing ring due to water scaling has been a long-standing problem. Designing the bellows seal as an external cooling or static structure can effectively prevent its scaling. If the structural design is unreasonable or improperly applied, the bellows seal is also prone to scaling, resulting in seal failure. Therefore, Hengchang Metal Hose recommends When you use bellows, use disposable water for cooling, it is best not to use circulating water as cooling water. In this way, the sealing working environment of the bellows will be greatly improved and the service life will be extended.

Shanghai Sansheng Health Technology Co.,Ltd. with more than 20 years’ history is headquartered in Shanghai city. We enjoy very convenient traffic, near Pudong airport and Ningbo port. Shanghai factory covers over 24000 square meters, produces corrugated stainless steel tube. The branch factory is located in Yuhuan Zhejiang province, supply all kinds of brass valves and fittings.As a famous China flexible metal hoses manufacturers and custom metal flex hoses factory, our core business is the production of CSST corrugated stainless steel tube 304 (with high resistance to pressure and deformation ) for two different applications: Plumbing and Gas.We specialize in manufacturing and supplying a wide variety of water tube and gas tube, wholesale metal flex hoses, and all kinds of fittings. Our ISO9001 certification further assures our internal and external quality control. We guarantee our customers high-quality products, quick delivery, and direct and attentive customer service. All the while we continue to actively seek mutual cooperation in business and technology, advocating OEM and ODM projects. We are looking forward to working with you.