Key variables in the design of pipeline systems are pump efficiency, equipment reliability, and throughput flexibility since they significantly influence the pipeline operating costs.
Pumps commonly used in pipelines operate at high efficiency only at the Best Efficiency Point (BEP) capacity. Outside this capacity, efficiency decreases and the wasted energy is converted into harmful vibrations, noise and heat, contributing to premature pump failures. Conventional pumps do not provide capacity flexibility to a pipeline.
A horizontal split case pump with replaceable diffusers and capable of accommodating a series of impellers has been developed. An impeller/diffuser combination with a BEP capacity matching the pumping capacity is selected to maximise efficiency. Since it operates close to BEP capacity, minimal pump vibrations and noise improve pump reliability.
Hydraulic and mechanical design features of the pump, some concepts for the future and a discussion of the potential cost savings when used in pipeline systems are presented.