What should be measured during the assembly of the centrifugal pump rotor?
Thread Content
1. Measure the ellipticity and deflection of the journal, as well as the fit between the shaft and the coupling, and between the bearing housing and the outer ring of the bearing. 2. Measure the verticality and coaxiality of the bearing housing. 3. Measure the thermal expansion clearance of the bearing. 4. Measure the forward and backward movement of the rotor. 5. Measure the impeller vibration value. 6. Measure the ring gap. 7. Measure the sealing compression amount and the end-face specific pressure.
Those who study* and work with equipment must be clear about this
New pump installation or maintenance?
All 7 points are correct, but not complete; moreover, the inspection and measurement tasks for cantilever pumps and multi-stage double-support pumps have been mixed together； “3. Measure the thermal expansion clearance of the bearing? ”How is this measured? Is it the gland clearance? “5. Measure the impeller vibration value? ? Does this refer to the end face runout of the impeller or dynamic balancing? I can’t understand the terminology; here are a few additional points: 1. The clearance between the shaft and the impeller (this is very important – a slightly larger clearance allows the assembly to function, but it will cause more vibration). 2. The 5-point runout of the shaft (this must be checked; otherwise, it’s possible not to even detect if the shaft coupling is bent. The 5 points refer to the impeller, coupling, front and rear bearings, and seal). 3. The clearance between the gland seals of the front and rear bearing housings. 4. The clearance at the front and rear edges of the impeller, as well as its radial runout. 5. Dynamic balancing (it’s necessary to carry out this process according to standard requirements, but in practice, as long as there was no significant vibration before, companies prefer to just replace the bearings or seals rather than waste money on balancing). 6. If it’s shaft bearings, then the clearance at the top, the tightening force, and the clearance of the oil seals. 7. Records of alignment data. 8. Values related to verticality, levelness at the bearing locations before and after testing, bearing vibration levels, bearing temperature, and the sound emitted by the bearings (using a stethoscope)