So What Did We Learn About Pumps During The Past 20 Years?

Abstract

The paper discusses and highlights the most prominent critical pump related challenges and experiences Eskom has been faced with during the past 20 years. The challenges include the following: The effects of Pump System resistance on pump operating point including NPSH requirements and cavitation problems; The effect of the boiler feed water quality on Boiler Feed Pump Mechanical Seal face life and the required changes made to seal face materials in order to be compatible with the required boiler feed water chemistry utilized; The advantages and disadvantages of gear type mechanical couplings compared to flexible membrane couplings as used on critical pumps; Experiences and lessons learnt through retrofitting Boiler Feed Pumps designed in the 1960’s utilizing modern design tools and technology; The selection of coating applications for different pump components; The pros and cons of having a long term contract / partnering agreement with a partner or a pump supplier; BWCP’s (Boiler Water Circulating Pumps) experiences and progress made in refurbishment in South Africa utilizing OEM and Non-OEM repairers; The effects of, and the resultant costs incurred, as a result of the unavailability and unreliability of the Feed Pump Driver (Steam Turbine).