Practical Method to Prevent Liquid-Column Separation

This paper describes a practical method to prevent the phenomenon of liquid-column separation in a pipeline by increasing the polar moment of inertia of the rotating parts of a pump-motor unit. Two examples are presented in detail. The examples indicate the following advantages of this method over other methods (e.g., installing air valves, air vessels, or one-way surge tanks in a pipeline): (1) low in cost for small-capacity motors; (2) safe and reliable; (3) not limited by conveyed media and climates; (4) no additional maintenance required; and (5) applicable to any pumping projects when the size and weight of motors are not limited in manufacture.