High temperature condensate pump motor bearing cause analysis

Condensate pump motor bearing high temperature cause analysis - 2018 10 - 02 a background of a nuclear power plant, case condensate pump put into operation three years later, the motor bearing temperature is too high, reached more than 80 degrees. To discover the cause of the high temperature, bearing grease and fat new samples sent to widely used to grind test detection. The motor grease for 3 # extreme pressure lithium complex grease, use time for three years, fatliquoring cycle for three months, with old fat is liquid. Second, the monitoring condition 1) New fat test results of condensate pump motor bearing new fat samples were analyzed, and find new fat drop point is low, the sintering load is low, cannot meet the requirements of extreme pressure lithium complex base grease. 2) Old fat analysis due to the use fat has liquid, can't be measured as grease, only through infrared spectrum were analyzed. Through infrared spectrum detection, found in fat on the characteristics of the wave number around 1580 significantly lower peak intensity, indicates that the soap base fiber grease has damage failure. 3) Wear new fat and comparative analysis with spectral element found in fat fat, fat elements Cu, zinc content in the relatively new fat increased significantly, system of copper zinc alloy parts in the system the existence of abnormal wear. Three, 1 case revelation) Bearing high temperature is the main reason of the abnormal wear and tear, and the cause of the abnormal wear and tear is bearing grease consistency, thixotropic performance degradation and adhesion performance degradation, lubrication part from erosion, cannot have normal lubrication effect, lead to bad lubrication friction pair surface. 2) Grease consistency decrease is the direct cause of fat in the soap base by external force, the permanent fault, lost to keep the effect of base oil, base oil precipitation, present a liquid state. 3) New fat drop point and sintering load is low, does not accord with the requirement of extreme pressure lithium complex grease. In addition, the soap base fracture failure after bearing grease, show that the mechanical stability and colloidal stability is poor, poor ability to resist shear. 4) Motor bearing belongs to the high speed bearing, higher requirements on the shear resistance of the grease, the grease of shear resistance cannot meet the operation requirements of motor bearing, it is the leading cause of bearing heating, grease failure root cause.