Discussion on the individual testing of waste heat recovery fans
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Let’s talk about the operating conditions of the equipment first. The design operating conditions for this fan are a flue gas temperature of 250 to 290 degrees, and an air density of 0.59 to 0.62 KG/CM3. The motor speed is 1486 RPM, with no transmission or anything similar. The unit has not yet been started, so for now a single-unit test at ambient temperature is being carried out. Under normal conditions, the air density is approximately 1.2 KG/M3; therefore, with a high load, the performance during testing will certainly not reach the designed levels. The argument now is that, according to my colleague, it’s sufficient to run it for 4 hours with the inlet dampers fully closed. Once the device is put into operation, performance tests will be conducted under actual operating conditions. I agree that performance tests should be conducted under actual operating conditions, but I’m not sure about running the inlet dampers fully closed for 4 hours – is it really necessary to conduct such a long-duration no-load test? ? I understand that the flow rate at low temperatures certainly won’t meet the requirements under normal operating conditions, but it’s also not feasible to keep all the dampers closed; in my opinion, the purpose of such testing isn’t clear. I think the air damper can be gradually opened within the motor’s rated current limits; the ultimate goal is to avoid overloading the motor, while also monitoring the temperature and vibration of the equipment. Please give your suggestions, Heyou. :Q
It’s not good to have the dampers completely closed, right? Will surge occur? The opening degree is generally required to be 15%.
I agree with you; let the motor operate at its rated current.
This post was last edited by wawa*n*ntaozi on 2017-12-25 at 14:14. It is okay to conduct a test run with the air valve open, but centrifugal pumps still need to be tested for their performance using water; they may not be able to pump water after use. If you really don’t know, just ask the manufacturer
Under test conditions, the outlet pipeline system is pressure-free, so there is no possibility of surge； The purpose of this test run is a mechanical test – mainly to test the fan, with the motor also being tested as well. The goal is to evaluate the mechanical properties of both the fan and the motor. As for 4 hours, that’s not necessary. A more reliable approach is to close the outlet valve and run the system for 45–60 minutes, then measure the bearing temperature rise and vibration levels; once that has been done, it’s sufficient~~~~~
I think it’s still necessary to check the temperature and vibration of the bearings. Since air isn’t being used, I wonder if some other gas could be used as a substitute
Your suggestion is good; running with all the dampers closed for 5-10 minutes will suffice as long as the motor does not experience overcurrent, with the main focus being on observing the vibration of the transmission part.