Vibration source and discrimination of motor and pump body in deep well pump

Vibration source and discrimination of motor and pump body in deep well pump
(1) the motor rotor imbalance. The imbalance of the motor rotor is the most important and common vibration reasons, such as: 17 #, 19 # motor, with the speed meter (displacement meter) measured motor vibration speed of 9.8-l0mm / s, control IS02372 vibration speed standard, Class III machinery should be less than 4.5mm / s, and in the 9.8-l0mm / s state, with the vibration meter measured the motor amplitude to 0.30mm.In order to find out the motor rotor imbalance, we made two Steel frame were erected two parallel rails (to pay attention to the steel frame should have sufficient rigidity), rail surface treatment into a smooth cleansing, with a level instrument to adjust the level of the rail surface and fixed. Check the motor rotor placed on top of the two rails, hand-driven rotor metering pump imported rolling back and forth many times, each time after its static, the rotor under the mark. With the adhesive sticky at the symmetrical point on the weight position, and then the rotor several times until the rotor can be stopped at random positions, to confirm the motor rotor has reached a state of static equilibrium. Equivalent to replace the adhesive paste quality, complete the work of the motor rotor balance. If using the above method still can not solve the problem, you need to balance the motor rotor test. The two motors that increase in the rotor side of the balance weight of 45-5g, the amplitude value reduced to 0.05mm, with the displacement meter measured vibration velocity of 2.1mm / s or so.
    (2) deep shaft submersible pump rotor speed is close to the critical speed. Can be calculated by the motor shaft torsional stiffness and motor torsional vibration frequency is the same as the motor critical speed, pump angular frequency and frequency close to resonance. Especially the first use of the motor, the occurrence of vibration failure, to analyze and calculate. The operating speed of the motor rotor should be at least 25% below the critical speed or above 40% of the critical speed. In the analysis should also take into account the quality of the motor rotor can not be reduced to focus on the quality of the situation, but along the axis of distribution, so the analysis of the critical speed should be analyzed to the second and third order and other major critical speed. In this case,
(3) has been a normal use for some time on the motor, the vibration reason to check whether the bearing clearance is too large, the shaft seat screw is loose, whether the shaft wear and bending or a part of the winding short circuit, air gap, the rotor and The gap between the stator ring gap is generally not more than 10% .In particular note that the motor amplitude value close to the standard value, that is still within the qualified range of circumstances, with the load after the motor amplitude will often exceed the standard, which is Because the vibration of the deep well pump transmission system is the result of mutual influence and interaction