Permanent magnetism canning pump

Abstract

The invention provides a permanent magnetism canning pump, and in particular relates to a plastic or plastic-lined pump which is suitable for application such as the conveying, pressurization, circulation and the like of highly-corrosive chemical liquid. Aiming at the improvement of a supporting structure of a rotor system, a high-rigidity cantilever type fixing shaft structure is provided to meet various requirements. The high-rigidity cantilever type fixing shaft structure is characterized by comprising a high-rigidity metal shaft, a ceramic shaft sleeve, a motor rear frame and a sealing rear cover, wherein the high-rigidity metal shaft is fixed to the motor rear frame and forms a fixing shaft with the ceramic shaft sleeve; the ceramic shaft sleeve is used for forming the fixing shaft by combining with the metal shaft to support the rotation and the axial anti-thrust function of a motor rotor; the motor rear frame is used for fixing the metal shaft to strengthen the supporting strength of the fixing shaft and providing the sealing function of a motor coil by matching with the sealing rear cover; and the sealing rear cover is provided with a middle open pore through which the metal shaft can pass, and the inner space of the sealing rear cover is used for accommodating the motor rotor and providing the sealing function of a motor stator coil.

Description

technical field [0001] Because the producers pursue the maximum efficiency of production equipment, they hope that the same pump can be used in high flow and low head, and can also be used in high head and low flow conditions. However, the production line managers do not consider many factors. There must be many pumps of different specifications in standby at any time, so that the permanent magnet canned pump is gradually valued by users; the present invention also makes further improvements to the above solutions, and the innovative pump structure enables the permanent magnet canned pump to meet needs for various uses. [0002] The present invention provides a canned shaft-sealless pump driven by a permanent magnet motor, hereinafter referred to as a permanent magnet canned pump, which is especially suitable for plastic or plastic internal pumps for the delivery, pressurization and circulation of highly corrosive chemical liquids. Lined pump; because the highly corrosive che...

AI Technical Summary

Problems solved by technology

[0021] (1) The problem of insufficient bonding strength of plastic and ceramic materials due to the difference in thermophysical properties

[0022] (2) The strength reduction of plastic materials at high temperatures

[0023] (3) The problem that the centrifugal force increases when the operating speed exceeds the rated speed

[0025] (1) The strength of plastic materials: the strength of many corrosion-resistant materials cannot be compared with that of ceramic materials, especially when the temperature increases, the material strength decreases greatly, and some plastics still have good strength when the temperature increases, but their corrosion resistance is insufficient.

[0026] (2) Thermal deformation of plastic materials: Many corrosion-resistant plastic materials have poor thermal deformation resistance and cannot maintain close bonding with ceramic materials

[0027] (3) High-speed centrifugal force problem: the mass of the motor rotor is large, and there is a gap required for lubrication between the hydrodynamic pressure bearing and the fixed shaft, which will increase the burden on the centrifugal force of the fixed shaft, and the centrifugal force will increase as the second power of the speed ratio , when the pump is running at a higher than rated speed, the fixed shaft must bear higher centrifugal force

[0029] British Patent No. GB2417981 adopts the design of cantilever fixed shaft structure, and uses high rigidity structural parts at the bottom of the sealed back cover to shoot together with the fixed shaft, so that the plastic material and the fixed shaft can be tightly combined and the supporting force of the shaft can be improved. This patent uses The material is high-temperature-resistant and high-strength engineering plastics, but this material cannot meet the needs of highly corrosive liquids such as hydrofluoric acid; since the previous patent is used for engine cooling water circulation, there is no corrosion resistance problem, but As far as the plastic material is used in corrosion-resistant applications, the combination of the fixed shaft and plastic, and the combination of other metal parts and plastics, cannot completely seal highly corrosive liquids; secondly, the cylindrical part of the back cover The thickness is thin and the rigidity is insufficient, and it is easy to cause displacement or misalignment of the fixed shaft

[0030] In addition, Japanese Patent No. JP2005299559 is a fixed shaft structure with bilateral support. A tripod is used at the pump inlet and an additional rigid structural member is used at the bottom of the rear cover to strengthen the support of the fixed shaft; the focus of this patent is on the The weight of the rotor is designed to reduce weight. This feature effectively solves the weight problem of the rotor; but its structure still cannot meet the problem of softening and deformation of the plastic material on the cylindrical part of the back cover under high temperature, the deformation of the tripod at high temperature, and the second rigidity. Structural parts must be used in highly corrosive liquids. This patent is only applicable to the use of non-corrosive liquids in engine cooling water circulation

[0031] The above solutions cannot provide a complete answer to the high-corrosion and high-temperature chemical liquid process, so the present invention will provide the best solution to the above problems to meet the needs of users

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