SEVERE PRESSURE SURGES IN A SIMPLE PUMP-PIPELINE-VALVE SYSTEM (AND WHAT TO DO ABOUT IT)

A simple case study of a relatively high-friction pipeline with pump-a ssisted gravity flow (e.g., for high viscosity fluids such as hydrocar bon products) illustrates three features which lead to unexpectedly hi gh transient pressure surges for which conventional alleviation practi ces (such as extended valve-closure times or surge-relief devices at t he pump discharge) are ineffective: (i) the use of a valve to control flow in a long or high-friction pipeline; (ii) a system with a valve c losure a significant distance downstream of a pump; and (iii) a system where surge protection is located a significant distance away from a control valve.