Reason analysis for Season 2 of Blower Help
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I would like to continue the discussion with everyone. I replaced all the sealing elements of the rotor oil seals, enlarged the rotor balance disk, and modified the main thrust bearings to increase their load-bearing area. As a result, the performance of the machine has improved significantly today – there is no longer any burning of the thrust bearings. The outlet pressure is 0.27 MPa and the flow rate is 750 cubic meters per second; however, the temperature of the thrust bearings is relatively high at 60 degrees. When pressure is applied to the main fan, the outlet pressure rises to 0.28 MPa and the flow rate reaches 800 cubic meters per second, at which point the temperature of the main thrust bearings rises to 70 degrees, triggering an alarm. I would appreciate it if everyone could help analyze what the cause might be and suggest ways to keep the thrust bearing temperatures stable under high pressure. Thank you! The user requires an outlet pressure of 0.3 MP and a flow rate of 1000 cubic meters per second
I’m not sure whether the high temperature applies to all the thrust bearings in general, or only to individual bearings. If it’s the latter, it is recommended to check for variations in the thickness of the thrust bearings, as well as any deviation in the alignment of the thrust disc, and the perpendicularity between the radial bearings and the thrust bearings； If all of them are high, it is recommended to check the balance drum clearance, whether the lubricating oil has deteriorated, and whether the oil supply temperature and pressure are normal. If nothing is wrong, then the issue should be traced back to the design stage
Check whether the return oil flow is unobstructed? Grinding of the thrust pad entry angle.
The reason is still excessive thrust; as pressure and flow rate increase, the axial thrust also rises, which inevitably leads to an increase in the temperature of the main thrust bearings. Your approach is also very correct – by increasing the area under stress on these bearings, to design a product that meets users’ requirements it is necessary to determine the relationships and balances between pressure, flow rate, thrust, and bearing temperature. Some companies have very comprehensive data on this. If improvements are made only at the technical level, they can at most reach the limits allowed by the design
I don’t know what kind of blower this is – why does it trigger an alarm when the thrust bearing temperature reaches 70? Ours is a compressor; the temperature alarm for the large thrust bearings is set at 105 degrees. It would be best to measure the thickness of the tiles. What is the shaft displacement? What is the thrust bearing clearance?
As the force-bearing area of the main tile increases, the friction surface also increases, which in turn leads to an increased heating area; however, heat dissipation does not seem to improve
Thank you for the review! Because the fan is really too old! A product from 81!
I plan to increase the return oil flow rate, which will help remove some of the heat from the oil. If that still doesn’t solve the problem, I will recommend that the user have a thorough inspection of the main unit.
The user requires an outlet pressure of 0.3 MP and a flow rate of 1000 cubic meters per second. What parameters were used in the design of the fan?
After reading the comments from each floor, I have a rough idea of the details. Changing the balance disc is indeed a great idea; you’re really amazing. If the issue still lies in the excessively high temperature of the thrust bearings, it indicates that the balance disc may still need to be modified further. Could an additional oil injection port or something be added near the thrust bearing? Although this would increase the oil return flow rate, the amount of oil that actually reaches each point also increases only slightly. I suspect that a significant increase in cooling is required for your thrust pads.