Abstract: Based on the vibration analysis of large-scale deep well pumps and various reasons that may cause vibration, a simple method of judging the motors and pumps in the field is proposed. Panzhihua Iron and Steel in the upper reaches of the Jinsha River has built a large deep-well pump station, the pump station consists of two 18m ID, deep 31m deep and the upper plant form. The Jinsha River flows into the deep well via 4 Dg1200 pipes. The upper part of the deep well houses 20 sets of 30JD-19x3 sand control deep well pumps on a reinforced concrete frame beam with a cross-section of 1450mm × 410mm. After a long period of installation and maintenance, we made some explorations on the causes of vibration. First, the deep well pump related technical performance parameters Model: 30JD-19x3, three impeller flow: 1450m3 / h drive shaft length: 24.94m, a total of 9 shaft pump shaft diameter: 0 80mm shaft material: 40Cr speed: 985r / min thrust Oil temperature: <50 ℃ Cooling water pressure: 0.8MPa Yang pipe diameter: 500mm Head: 80m Rubber bearing lubrication medium: water without motor Single weight: 14t Vertical motor model JKL15-6 Rated power: 500kW Rated voltage: 6000V Rated current: 60A Motor rotor moment of inertia: 58kg · m2 Motor weight: 4t Motor and pump vertical and horizontal allowable amplitude: <0.l0mm This deep well pump water quality requirements of not more than 0.1% sediment, particle size of not more than 0.2mm , And the first impeller of the pump should be immersed in water level lm below. At present, during the floods in July and August, the highest concentration of water in the Jinsha River from deep-well pumps is nearly 20%. Second, the vibration fault judgment Pump and motor vibration occurred during operation, when conditions, the first should disconnect the coupling between the two, the vibration source is from the pump or motor, and carefully check the vertical motor base and Pump connection bolts are tightened, the installation level is over tolerance. 1. Motor vibration source and determine (1) the rotor speed is close to the critical speed. It can be calculated by calculating the motor shaft torsional stiffness and torsional vibration motor frequency with the motor critical speed, pump frequency and frequency close to produce resonance. In particular, the first use of the motor, the occurrence of vibration failure, to be analyzed and calculated. Motor rotor speed should be at least below the critical speed of 25% or higher than the critical speed of about 40%. In the analysis, we must also consider that the quality of the rotor of the motor can not be simplified into the concentrated quality situation but distributed along the rotation axis. Therefore, the critical speeds such as second and third order should be analyzed when analyzing the critical speed. (2) Motor rotor imbalance.