Effect of Intake Maintenance on Pump Reliability and Performance

The trend toward higher speed, higher power density liquid turbomachinery has inevitably increased the potential for fluid/structure interaction problems, and the severity of those problems. Fluid structure interaction phenomena can lead to increased wear and to structure failure. There are many factors affecting hydraulic and dynamic performance of pumping plants. These factors contribute to decrease performance efficiency, increase maintenance and replacement costs, and decrease reliability and operating life of the plants. Fortunately, vibration is a good indicator of pump performance and can early predict any failure or damage avoiding sudden breakdown. Through vibration monitoring, reliability and safety of pump plants can be ensured. Vibration analysis offers a comprehensive method of identifying a variety of pump problems. Aquatic weeds and waste pollutants in the sump basin of pump plant block pump intake, reduce pump suction, and produce hydraulic problems affecting performance and efficiency of the plant. Hydraulic problems contribute significantly to downtime in pumping stations. Maintenance of pump intake is very important to ease water entrance to the plant, decrease consumed power, and avoid flow problems such as turbulence and eddies in the intake. In this research, dynamic and hydraulic performance was recorded on Al-Twesa Pump Station, Kom Ombo, Aswan. Heavy deposits and biological growth are found in the suction basin of the station. The primary results show that pump discharge is smaller than that designed and the vibration level is high. Amplitude of vibration is directly proportional to the amount of dynamic loads generated. Measurements were repeated after removing of aquatic weeds and cleaning the sump basin, and the results show that intake maintenance decreases vibration level from 25 % to 70 %. Hydraulic power increased 50 %, overall static efficiency reached up to 70 % as well as reliable and safe dynamic performance achieved. The research points out the importance of regular maintenance and cleaning of pump intake with regular vibration monitoring to early predict and diagnose pump faults, and maintain efficient pump performance and water requirements.