Convection and fully-cooled type end cover structure for novel roots pump

Abstract

The invention relates to a convection and fully-cooled type end cover structure for a novel roots pump. The convection and fully-cooled type end cover structure comprises an end cover body and is characterized in that the end cover body is in shape of a geometrical octagon; inner end cover cooling grooves which are annually distributed are formed in the inner surface of the end cover body; outer end cover cooling grooves which are also annularly distributed are formed in the inner surface, on the outer side of each inner end cover cooling groove, of the end cover body; and two symmetrically-distributed vacuum sealing grooves are formed in the inner surface, on the inner side of each inner end cover cooling groove, of the end cover body. According to the convection and fully-cooled type end cover structure for the novel roots pump, a roots pump body is high in strength and rigidity due to the end cover in shape of the geometrical octagon; two independent cooling chamber layers are formed, thereby two independent cooling falling lines can be formed by the cooling liquid, and a convection mode can be formed as well; the convection and fully-cooled type end cover structure can be used in match with a novel jacketed type fully-cooled roots pump, therefore, sufficient cooling liquid can be provided for dissipating the heat generated by the roots pump in running, and as a result, the potential risk that a rotor is heated and expanded to result in locking as the roots pump is overheat can be completely solved, and lubricating oil in a shaft chamber of the end cover can be kept at a certain temperature for running.

Description

technical field [0001] The invention relates to the technical field of front and rear end covers of a Roots pump, in particular to a design for an end cover of a totally-cooled Roots pump, and in particular to a mechanical structure of an end cover of a Roots pump. Background technique [0002] At present, the end cover of the Roots pump is generally in the shape of an oval or a circle. There are two deficiencies that are difficult to overcome when the Roots pump is running. Since the Roots pump cannot be used alone as a vacuum pump, it needs to be equipped with a backing vacuum pump. Otherwise, gas will accumulate at the exhaust port of the Roots pump, forming a pressure difference between the exhaust port and the suction port of the Roots pump. When the pressure difference is too large, when the rotor of the Roots pump compresses the gas at the exhaust port side, it needs more work. According to the gas compression heat balance, the greater the gas compression work, the g...

AI Technical Summary

Problems solved by technology

When the temperature in the pump body of the Roots pump is getting higher and higher, the expansion of these metal parts will be greater, exceeding the gap between the rotor and the pump body or the end cover of the Roots pump, and metal collision will occur until the rotor is stuck, causing Roots pump damage

[0003] If the gap between the rotor of the Roots pump and the pump body or the end cover of the Roots pump is too large, the pressure difference between the two ends will cause a great loss of vacuum at the inlet of the Roots pump.

It can be seen that if the inlet of the Roots pump reaches a high degree of vacuum, the gap between the rotor of the Roots pump and the pump body or the end cover needs to be small, but if the gap is too small, it is easy to cause an excessive pressure difference, and the compression heat cannot be timely The removal causes the rotor, the pump body and the end cover to be stuck

At the same time, for some harsh use environments, the high surface temperature of the pump body will also cause dangerous hidden dangers, so removing the gas compression heat of the Roots pump in time is the core key to improving the performance and safety of the Roots pump

[0004] At the same time, if the compression heat cannot be removed in time, the accumulated heat will cause the temperature of the Roots pump pump body to rise, which will be transmitted to the end cover and further to the parts at the end cover, so that these parts include bearings, seals and lubricating oil. It will run at high temperature. Once the temperature is too high, it will seriously affect the service life of the parts. Due to such hidden dangers, the existing Roots pump uses a piston ring between the impeller and the end cover to resist lubricating oil. Splash into the impeller, but it is not completely sealed after all, so it will take a long time to reach the ultimate vacuum, and the problem of acid gas corrosion is difficult to solve. However, if a mechanical seal is used, it is also difficult to guarantee its proper performance due to high temperature operation. service life, and the replacement of mechanical seals is not the best choice for Roots pumps because of the inconvenience of disassembly.

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