A friend of Ms. Shen who is engaged in design said that their company has a batch of high-efficiency motors exported, and the type test results of motor efficiency are much smaller than the design value, but the small technicians who followed up said that the dimensions of all parts meet the requirements. When he was puzzled, the worker who tested the motor said inadvertently: The bearings of this batch of motors are not good, and they will not move! The later inspection is indeed a problem with the bearing.
The reason for this problem is that the design requires the use of 2RZ bearings. As a result, a 2RS bearing was purchased due to a problem in the procurement process . So what is the difference between a 2RZ bearing and a 2RS bearing?
Simply put, 2RS is a two-sided rubber seal, 2RZ is a two-sided dust cover seal, one is a contact type and the other is a non-contact type. The noise of 2RS is small, but the accuracy is not too high to reach P5 level. The basic dimensions of both bearings are the same. Whether it can be used generally depends on your application. The sealing effect of 2RS is better than that of 2RZ , but the friction resistance is slightly larger. If it is required to be well sealed, such as no oil leakage, it is best to use 2RS .
In the actual production and processing process, in addition to the structure and quality of the bearing itself, it is also related to the cooperation of grease and bearing. After some motors are started, they will be very flexible after rotating for a period of time; for manufacturers with conditional monitoring data, the most It is intuitive that the no-load current and no-load loss will increase from large to small and tend to be stable as the motor rotates.
Individual customers will control the downtime of the motor. From the test data, it can be found that the efficiency of the motor with a relatively long downtime is better than that of the motor with a relatively short downtime.
Another friend of Ms. participating in the experiment, Sister C , did accumulate some data. This type of data is very useful. Their unit adjusted the bearing chamber size based on these data, and the effect was very good.
From the actual facts, it can be found that the cycle from theory to practice and then to theory is the improvement process of the interaction between motor designers, manufacturers and testers.
Post time: Jun-07-2022