1. Ten causes the centrifugal pump vibration big reason - - Pump type selection and variable operating conditions:
Each pump has its own rated point, the actual operating conditions and design conditions are in line with the pump's dynamic stability has an important influence. Pump operating conditions in the design is relatively stable, but under variable conditions in operation, due to the role of radial force in the impeller, the vibration has increased; single pump selection is improper, or two models do not match the pump in parallel. These will cause the pump vibration.
2.Ten causes of centrifugal pump vibration of the major reasons - bearing and lubrication :
Bearing stiffness is too low, it will cause the first critical speed is reduced, causing vibration. In addition, the guide bearing closed due to bad performance of poor wear resistance, poor fixation, larger bearing clearance, also easy to cause vibration; and thrust bearings and other rolling bearing wear, will make the longitudinal axial dynamic vibration and bending vibration also increased. Improper selection of lubricating oil, deterioration, excessive content of impurities and lubrication pipeline caused by the lubrication failure, will cause the deterioration of the bearing conditions, causing vibration. Motor sliding bearing oil film of the self excitation will also produce vibration.
3.Ten causes the centrifugal pump vibration big reason - - pipeline and its installation fixed :
The pump outlet pipe bracket stiffness is not enough, the deformation is too large, resulting in the pipeline under pressure in the pump body, the pump body and the motor of the neutral pipeline during installation failure; the rivalry is too large, the import and export pipeline is connected with the pump when the internal stress is large; the inlet and outlet pipeline is loose, the restraint stiffness decreased even the outlet channel failure; all parts of fracture fragments card impeller; pipeline is not smooth, such as the outlet air bag; outlet valve board, or did not open the water inlet; air intake, uneven flow, pressure fluctuation. These causes can directly or indirectly lead to pump and pipeline vibration.
4.Ten caused by centrifugal pump vibration of the major reasons - the coordination between parts :
The motor shaft and the pump shaft concentricity error; at the connection of the motor and the drive shaft using the coupling, coupling concentricity error; static and dynamic components (e.g. between Ye Lunyi and ring) wear design gap becomes large; intermediate bearing bracket and the pump cylinder clearance exceed the standard ring gap is not proper; unbalanced; gap sealing ring around the uneven, such as ring grooves or not partition no slot, this occurs. These adverse factors can cause vibration.
5.Ten caused by centrifugal pump vibration of the major reasons - impeller :
Centrifugal pump impeller mass eccentricity. The quality control is not good in the process of manufacturing, for example, the casting quality and the processing precision are not qualified; or the liquid is corrosive, the impeller flow channel is corroded, resulting in the eccentric impeller. The number of blades, the outlet angle, the angle of wrap, the radial distance between the throat and the throat of the impeller and the radial distance between the impeller and the impeller are suitable for the centrifugal pump. Between the impeller and the pump body of the centrifugal pump, the stage between the sleeve and the spacer sleeve, the initial rub, gradually become mechanical friction and wear, which will increase the vibration of the centrifugal pump.
