know and understand centrifugal pumps pdf

Very few industrial pumps come out of service and go into the maintenance shop because the volute casing or impeller split down the middle, or because the shaft fractured into four pieces. The majority of pumps go into the shop because the bearings or the mechanical seal failed. Most mechanics spend their time at work time greasing and changing bearings, changing pump packing, and mechanical seals. The mechanical engineers spend their time comparing the various claims of the pump manufacturers, trying desperately to relate the theory learned at the University with the reality of the industrial plant. Purchasing agents have to make costly decisions with inadequate information at their disposal. Process engineers and operators are charged with maintaining and increasing production. The focus of industrial plant maintenance has always been that the design is correct, and that the operation of the pumps in the system is as it should be. In this book, you will see that in the majority of occasions, this is not true. Most of us in maintenance spend our valuable time, just changing parts, and in the best of cases, performing preventive maintenance, trying to diminish the time required to change those parts.