1, with excellent follow: as the bellows seal itself completely closed structure, the structure eliminates the common spring seal must have in static ring and the shaft sleeve (or shaft) of the dynamic sealing ring, so that the elastic corrugated pipe is used to form sufficient pressure (and common seal the seal rings there, in the ring sleeve relative displacement requires a partial balance of force. The friction force between the sealing ring and the sleeve (or shaft) makes its position, the size of the balance force be limited by the processing accuracy and the heat treatment of the sealing ring, which shows its excellent following. In the process of using ordinary mechanical seal device often because of fluctuations or operation process and other aspects caused by the pump body to the phenomenon, the moving ring of the sealing ring to open the end there can not be reset, and the leakage of the mechanical seal and bellows mechanical seal, the seal failure way to eliminate the structure. The pump body is almost not affected by the time, shows its compensation and good, in the light hydrocarbon pump evacuable, decompression tower bottom pump in the outstanding performance, this feature is bellows seal to one of the important reasons of the popularization and application.
2, high temperature resistance as the bellows seal ring off effect of ordinary spring seal sealing ring in the medium temperature and suitable is greatly expanded. The ordinary mechanical seal ring seal material with PTFE rubber and other organic compounds, these organic compounds in some medium, with medium body to produce chemical reaction at low temperature and high temperature conditions, will change its physical properties, have hardened sealing failure, bellows seal without the above factors limit tube, usually applies to benzene, ketones, olefins, alkanes and general oil, acid, alkali and salt and other media, but also by the temperature range – 250 degrees – 450 degrees, of course, this is also the need for strict selection of welding and heat repair of metal bellows.
3, the balance of the bellows seal compared with ordinary mechanical seal, does not need to be processed with steps in the sleeve, itself can establish the equilibrium diameter in equilibrium (usually partial equilibrium) when external corrugated pipe size parameters can be adjusted to achieve the ideal state, corrugated tube sealing machine used in general balanced type.
4, less leakage points on the moving ring and the static ring sealing points are metallic (non-metallic) gasket sealed and connected by bolts, it is difficult to find the leak, leak essentially bellows mechanical seal friction pair only the dynamic sealing point, will greatly reduce the risk, and the general mechanical seal leakage channels there are three main dynamic seal ring, sealing ring and static ring end face friction. In this leakage channel, the seal leakage is 40% of the total leakage due to the failure of the dynamic and static ring auxiliary sealing ring.
5, shock resistance and high speed of bellows seal off the rotating sealing ring can reduce the pump vibration or shock caused by the transmission shaft sealing ring ring ring caused by the vibration, the dynamic ring from big impact, usually called the floating seal.
When the corrugated pipe is designed for static structure with damping device, the damper can effectively prevent the total shock generated in high speed condition with the shaft and the pump body, so the use of line speed has been greatly improved, the line speed of up to 100M/S.
6, can reduce the spring pressure in the ordinary mechanical seal spring in the process of using pressure than the general design in 0.15MPa 0.25 MPa, while the bellows seal spring pressure of the general design for the 0.05 – 0.15 MPa, bellows seal into static structure, spring pressure is obviously small. Therefore, the friction heat generated by spring pressure decreases, reducing the surface temperature, thereby reducing the amount of wear surface friction, which reduces the mechanical power, improves the sealing performance and prolongs the service life of the seal
7, can transfer torque in the ordinary mechanical seal operation, additional transfer structure must be sealed and the structure of a variety of forms, such as fork, pins, screws and the fastening to transfer torque performance, generally no extra torque can be used normally, to simplify the structure, avoid the transfer of structural failure the cause of the failure, improve the reliability of the mechanical seal, when the bellows mechanical seal working pressure exceeds the allowable torque, often in the structure increase fork structure, increase its anti torque capacity and stability, play a supporting role is widely used in high voltage and high speed sealing.
8, the design of a certain structure, can reduce the failure due to the scaling in the water seal: in many areas, due to poor water quality, scaling index is high, plus no water softening device specific and dynamic ring seal in common auxiliary seal ring for water scaling leads to the failure phenomenon of many has become a chronic problem.
The bellows seal design become cold or static structure, can effectively prevent the fouling, if unreasonable structure design or improper application of bellows seal is easy to fouling, resulting in seal failure, it is recommended to use the corrugated pipe, with cooling water as cooling water for the water, so that the bellows seal work environment will be greatly improved to extend the service life.
9, remove the oil seal, cost saving in high temperature and impurity pump with ordinary mechanical seal, due to a variety of auxiliary seal ring and the friction pair of group by the limit of usage temperature tend to friction around the injection of flushing oil (oil seal), lubrication, reduce the sealing cavity temperature to establish a suitable job in various components to adapt to the environment, but because the sealing oil flushing causing huge waste of money, choose the right amount of bellows seal can not hit oil seal oil seal save a lot of funds.
10, the design of a certain structure, can reduce the sealing failure due to the scaling causes: in many areas, due to poor water quality, scaling index is high, plus no water softening device specific and dynamic ring seal in common auxiliary seal ring for water scaling failure phenomenon has become a lot of difficult the problem. The bellows seal design become cold or static structure, can effectively prevent the fouling, if unreasonable structure design or improper application of bellows seal is easy to fouling, resulting in seal failure, it is recommended to use the corrugated pipe, cooled with disposable water, preferably without circulating water as cooling water so bellows seal, working environment will be greatly improved to extend the service life.
Source: China Bellows Compensator Manufacturer – Yaang Pipe Industry Co., Limited (www.yaang.com)