TN series contact sealing device-a mechanism for preventing oil, water and hydrogen from leaking, as an important invention, won the national invention patent of 1994 (ZL 19 109382.4). Its unique structure is the first in the world. In the design concept, it has reached the highest level of large-scale high-speed rotating mechanical seal-the sealing teeth contact with the rotating shaft and seal without gap.
Second, the original structure analysis of oil mist
Because the rotor of the unit oscillates in operation, the gap between the traditional copper tooth seal ring (or felt seal, air labyrinth) and the rotor shaft can't guarantee the design gap and installation gap in actual operation, and it can't be compensated, and it can't form a stable oil film seal, which is easy to cause oil leakage and oil mist leakage.
Third, the role of each component:
(1) Multi-dividing function: the contact teeth of the contact seal cover are divided into several even-numbered equal parts along the circumferential direction, and each equal part can move back and forth in the radial direction, with high sensitivity and can follow the displacement of the shaft in the radial direction, thus ensuring that the contact seal cover of the thrust bearing can always run stably without clearance with the shaft;
⑵. Back-compensation function: After the contact teeth are equally divided, each division can move forward and backward radially, with a forward distance of 1mm and a backward distance of 2.5mm, which is extremely sensitive, and can effectively compensate the wear in operation, so that the contact teeth can continuously contact with the rotating shaft and ensure that the contact teeth and the rotating shaft can run without gaps under any working conditions;
(3) Limit function: The accurate limit device can effectively limit the feed of the contact teeth, reduce the wear between the contact teeth and the rotating shaft, and ensure that there is always zero clearance between the contact teeth and the rotating shaft.
⑷. Material in contact with the rotating shaft: The material in contact with the rotating shaft is a nonmetallic multi-component composite material independently developed, which has the characteristics of wear resistance, oil resistance, high temperature resistance, aging resistance, chemical corrosion resistance and self-lubrication.
(5) Aluminum alloy seat ring: the mother body and the supporting parts are made of special light aluminum alloy, which has the characteristics of beauty, generosity, portability and no deformation after special surface activation treatment.
(6) Oil mist filtering respirator (steam chimney): The breathing filter consists of cover, body, baffle and oil collector. Years of experience accumulation and mature design are the remarkable characteristics of oil mist filter respirator. It can make the oil mist condense into oil droplets in the process of passing through the baffle to the oil collector, return to the oil tank, and exhaust the filtered air, so that the pressure difference inside and outside the oil tank is consistent.
To sum up, the contact sealing cover can effectively solve the problems of oil throwing and oil mist leakage of the unit. The biggest feature of this contact sealing device is that the contact teeth (the material itself has the characteristics of wear resistance, high temperature resistance and self-lubrication, and will not damage the rotating shaft, cause vibration and raise the temperature of the shaft) directly contact with the rotating shaft, which has good radial tracking function. This contact sealing device ensures and limits the pressure between the contact teeth and the rotating shaft through a complete mechanical chain. Under the control of this complete mechanical chain, the contact teeth and the rotating shaft can contact each other to form a gap, which includes both dynamic operation and static needs, and organically combines dynamic and static to meet the needs of various pressures in operation. This kind of contact seal is ingenious in design and reasonable in structure, which contains all the functions that may be needed in the real working condition of the dynamic-static joint, so as to achieve long-term and effective ideal sealing effect.