This paper presents a new pump concept, called the New Progressing Cavity Pump (NPCP). The NPCP is composed of a Progressing Cavity Pump (PCP) and a system of Hydraulic Regulators (HR) installed inside the pump in between the cavities. The HR are self-regulated devices that recirculate the fluid between the cavities in order to control the pump thermo-hydraulic response and to avoid excessive built up of heat, which might result in premature failure of the pump's stator.
It is common knowledge that the traditional Progressing Cavity Pumps (PCP) have shown significant problems when dealing with multiphase mixtures, with high gas void fraction (GVF). We propose a new concept, NPCP, which is able to handle much better such conditions, as its internal hydraulic regulators (HR) recirculate fluid inside the pump. The benefits are multiple. First, it uniformizes the pressure across the pump length, which stabilizes the temperature. Second, it compensates the compressed gas volume of progressing cavities. Furthermore, it protects the stator and therefore, improves the pump's performance.
The relatively small dimensions of hydraulic regulators HR and their distribution along the pump result in an efficient multiphase design. Compared to traditional PCP, the new NPCP system better controls the reliability parameters, such as temperature and friction torque, reduces energy consumption and enhances hydraulic performance (flow rate, delivered pressure).
Several industrial NPCP have been manufactured and tested in liquid, both water and oil, as well in multiphase flow (air and liquid). This paper presents and describes the bench test results and shows that NPCP improves both reliability and hydraulic performance over existing pumps.