The undriven end of the distillation column bottom pump experiences significant vertical vibration
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The non-driven end of the distillation column bottom pump P203AB in the diesel hydrogenation unit experiences significant vertical vibration; this stream of diesel exits the unit； The vibration of the distillation column bottom reflux pump P204AB is normal. Vibration remains high after centering P203AB; what other factors could be affecting it? What is the impact of flow rate and bottom temperature?
What is the operating flow rate of the pump? What is the flow rate at the pump’s maximum efficiency point? What is the model of the pump?
Model 250AYS180: The normal operating flow rate ranges from 220 to 260; the liquid level in the fractionation tower is adjusted automatically based on the processing volume, with the outlet control valve being under cascade control with the liquid level. The bottom temperature of the tower is 260–270, adjustable according to product requirements. Design flow rate: 596, temperature: 320
What is the vibration value? Over 5 mm/s? 1. Check whether the coupling diaphragm is damaged. 2. Re-center if not damaged. 3. High bearing housing temperature; it could be an oil issue or a damaged bearing.
P203 has two pumps; despite multiple alignment attempts, the vibration level remains high at 6.6–7 mm/s, while the bearing temperatures are normal. Currently, it is considered to be a process-related issue, because if there’s a problem, it’s unlikely that both layers would be affected
Is the clearance of the bearing shells adjusted according to the temperature of the medium?
The pump inlet pressure isn’t reaching the design value, right? I’m not sure if it has any impact
The recirculation pump also hasn’t reached the design value, but the vibration is normal