Effect of rod stiffness change on the ‎performance of reciprocating pumps ‎and its starting requirements

Lots of solutions and methods were developed to deal with reciprocating pump systems’ starting requirements either the reciprocating pump driven by a wind turbine or electric motor (Ford et al., 2013). Decrease reciprocating pump-starting requirements in term of starting torque and starting current is a critical issue and should be considered in designing, sizing, and selecting reciprocating pump systems (Mahmoud Mohamed , 2013). In the present paper, the effect of rod stiffness change on the performance of reciprocating pumps and its starting requirements were experimentally studied using manufactured test rig equipped with closed loop reciprocating pump system. The system was driven by a squirrel cage electric motor through mechanical Scotch Yoke mechanism to transform rotational motion to linear (reciprocating) motion. Several experiments and the combination of the input parameters have been performed. Moreover, the outcomes and results obtained were explained, analyzed, discussed and the conclusion was drawn. The change of the reciprocating pump rod stiffness through the pneumatic cylinder improved the system efficiency and minimized the power consumption and the required starting torque. This approach experimentally proofed that the rod stiffness change has a great influence on the reciprocating pump performance and can decrease the reciprocating pump starting requirements. The starting torque requirements were decreased by an average of 19 %, power consumption corresponding to the peak starting torque were decreased by an average of 9% and the overall system performance and efficiency were increased by an average of 10%.