Can a centrifugal compressor operate continuously at speeds above its maximum continuous speed?
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Recently, one of our company’s centrifugal compression molding machines has been operating at 9337 RPM continuously, which exceeds the maximum continuous speed specified on the machine’s nameplate. I would like to know whether it is possible to operate it in this manner over the long term.
It definitely won’t work; the motor, bearings, lubricant – all of these components can’t handle it
Exceeding the rated maximum speed is certainly not good for the long-term operation of the machine operator. It has just not reached the tripping speed yet. Once the tripping speed is reached, the unit stops operating immediately.
This post was last edited by tie008 on 2018-3-8 at 13:13. The value exceeded 0.47%~~~ In theory, neither lubrication nor vibration should have any effect; however, if there are no significant changes in bearing temperature, exhaust gas temperature (temperature rise), or mechanical vibrations at various points, it is possible to operate the equipment under special care conditions on a cycle of about 3 months~~~~ I forgot to mention that there have been instances where the value exceeded 1%+ (on a continuous basis) after about half a year of operation~~~~
I asked on site, and it’s because the filter at the compressor inlet is clogged, which prevents an increase in flow rate; therefore, it’s not possible to shut down the machine to clean the filter for now. Therefore, increasing the speed is adopted to achieve an increase in volume. I want to ask if this will work? Does an increase in speed mean that the compression ratio of the compressor has increased? What is the relationship between flow rate, rotational speed, and compression ratio?
It seems that there is no problem operating at a speed that is 0.47% higher than the rated speed; short-term operation is acceptable, but it is still necessary to clean the filter to prevent damage to the various components of the compressor’s drive system. We have also had instances of short-term over-speed operation before, for about 1 month, at less than 1%.
Increasing the rotational speed should enable an increase in output volume; raising the speed essentially means increasing the load on the compressor in order to overcome the pressure drop caused by the inlet filter. However, there is a problem with operating in this manner over the long term: under such conditions, the steam control valve of the turbine may reach its maximum opening position, and over time it can get stuck at that setting (this tends to happen at the extreme positions)
An increase in the force causing the impeller to loosen is not good for the equipment; the overspeed is not too high, so it’s best to monitor its operation
The equipment must not operate at excessive temperatures, speeds, or under overload conditions