Questions regarding the expander
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I would like to ask the experienced colleagues what causes the expanders in our unit to stop operating repeatedly due to excessive vibration! No abnormalities were found after the last maintenance! ! !
What are the specific operating conditions? ? Was the vibration level measured in person or on-site by someone before the machine stopped working? ? Does it start vibrating and cause the machine to shut down right away, or does it vibrate for some time before shutting down? ? Is the lubricant level and quality normal? ? Please, the poster should pay attention to the content of their post and ensure it is logical! To be honest, it’s very difficult to express things in the way you describe, and few people can do it clearly.
First, check the instrument vibration system: the amplifier, the extension cables; and if conditions permit, check the probe as well. Check the oil temperature and the seal gas temperature; lower the seal gas temperature, and the vibration will decrease a bit. Also, check whether your process system is operating unstably and whether there are large fluctuations in the load. Then it’s not possible to inspect the bearing clearance and thrust bearing.
Using a data acquisition instrument for spectral analysis to identify the cause could be very helpful.
The high vibration level of the expander after maintenance is due to the following reasons: 1. Issues with the instrumentation and detection system, ranging from the probes and the cables leading to the control room to problems with the wiring that need to be thoroughly checked； 2. For process-related reasons, all parameters must be controlled in accordance with the operating procedures, especially the oil temperature and the pressure of the sealing gas ； 3. Reasons for maintenance and installation: The expander is a device that operates at high speeds, and its impeller has undergone high-speed dynamic balancing. If the rotor components are assembled incorrectly during maintenance – that is, if they are not assembled according to the specified markings – excessive vibration may occur during startup and acceleration, leading to an automatic shutdown of the equipment. In severe cases, this can even cause damage to the shaft seal ；