Through the design control of large industrial motor sliding bearing axial momentum

Through the design control of large industrial motor sliding bearing axial momentum - 2019 06 - 25 joki li gang zhi-qiang zhao abstract: through the analysis of the sliding bearing axial channeling move reason, this paper introduces a control shaft momentum of design thinking. Key words: sliding bearing; Axial channeling move; The motor; Design 1. Introduction at present large industrial motor bearings are sliding bearings, but USES the sliding bearing of the motor running condition of axis moving, the industry also can only control in & plusmn; The critical value of 1 mm, so there is no problem for most of the load, but for some special load, is very strict with axial channeling move, for example: the motor shaft channeling dynamic process must be in the start-stop control in & plusmn; 0. 3 mm, must through the design means control of the motor shaft up momentum. 2. Sliding bearing axial channeling move cause analysis, the main factor is the electromagnetic force symmetry, shaft bearing block alignment, plate tooth bounce off amount, air gap uniformity, frame alignment, the end cover of the end cover two check mouth alignment, assembly method and stator core alignment, etc. The above methods all the demands of the production process strictly, no doubt to ensure that the need to increase the cost, and can't fully guarantee to control the whole process of axial channeling move & plusmn; 0. 3mm。 Through the design time is needed to control shaft momentum. 3. Design ( 1) On the basis of conventional design, the use of sliding bearing thrust bearing surface to limit the axial displacement of rotor, bearing width is smaller than a shaft shoulder width 0. 6 mm, so motor to control the whole process of axial channeling move must & plusmn; 0. 3 mm, but, normally, so design, bearing shell temperature will be high, even more than 80 ℃, cannot use. Here is the detailed operation method. （ 2) First of all, according to the normal bearing shell design, bearing and shaft shoulder unilateral have 3 mm gap, and assembling them into the machine. Shaft center hole shaft extension end C type, design a round head bolt, installed on the center hole, at this point, you can do for the first time debugging, start the motor to the rated speed, a dial indicator is used to measure the motor shaft under rated speed up momentum of maximum and minimum values, when the dynamic value of shaft may be affected by the limit of shoulder, would not be accurate, so you also need to measure the rotor in the natural state stopped dynamic value, when the power is used to eliminate the influence of shaft shoulder limit and if there is a shoulder limit, using the data from the above three analysis is the inside of the shoulder or lateral shoulder limit, according to the analysis result in bearing and end cover gasket adjustment, increase or decrease until the elimination of the influence of shaft shoulder limit. Then do the second time debugging, the method is alexandrine, recording under the rated speed axial momentum of the maximum and the minimum, the motor is calculated from the two data can be actual runtime magnetic centerline, at this point, the need to use 0. 1 mm copper foil gasket fine-tuning until the pad under the theoretical calculation of bearing and shaft shoulder unilateral 3 mm. （ 3) Then you can change another pair of bearing bush ( Hereinafter referred to as the 'wide bearing) The bearing shell width compared with normal bearing width is a little wide, wide bearing minus 0 width by shoulder width. 6 mm, computing, the tolerance value should be taken into consideration, and then a third debugging, motor rated monitoring during the operation of bearing shell temperature and axial dynamic value, if the constant axial channeling dynamic value, and partial in one side, it could be on the other side of the shoulder and bearing friction in the operation process, need according to the axial dynamic values increase or decrease in copper foil, until the shaft can be packed before and after operation, and then detect bearing shell temperature, detection of two consecutive hours, temperature does not exceed 80 ℃, adjust the success. At this point, the motor start-stop process in channeling dynamic axis & plusmn; 0. 3mm。 4. Conclusion this design can without any increase in the cost of materials, on the basis of satisfy some special load on the motor axis channeling move & plusmn; 0. 3 mm. Source: 'the construction of science and technology, 2017, 7 ( Graphic)