Progressive cavity pumps (PCPs) consist of a rotor and a stator. The extrusion process of PCPs is governed by a single-helical rotor which rotates eccentrically within a double-helical stator of twice the pitch length. Between the seal lines (the contact lines of rotor and stator), there are cavities which are constantly moved towards the discharge end of the pump. As one cavity is eliminated, another cavity develops, keeping the cross-sectional area of the cavities constant. The process makes a continuous non-pulsating flow in the PCPs. The developed pushing–and–suction action allows PCPs to exert significantly lower shear rates on the pumped material, compared to other pump types, such as membrane pumps or peristaltic pumps. However, the sliding of the rotor and stator in the pump causes a biting phenomenon [1-3]. Therefore, the degradation of particles in the fluid occurs. In this study, we adopted a flexible, low-friction gels as the stator material. By using gels materials as stator, we could make a pump that could discharge at low torque as previously reported by our group [4]. In this work, the rubber stator and the gels stator fabricated by 3D printing were compared and evaluated by performing discharge and torque test.

References:

[1] K. Nishimura, E. Uetsuji, and Y. Iwai, “Study on the Behavior of Particles in the Sliding Portion of a Progressive Cavity Pump”, Journal of Japanese Society of Tribologists, Vol. 63 (2018), No. 9 pp. 641-650

[2] P. Fisch, M. Holub, and M. Z. Wong, “Improved accuracy and precision of bioprinting through progressive cavity pump-controlled extrusion”, 2021 Biofabrication 13 015012

[3] M. Horie, S. Shigemitsu, S. Ookura, “Fundamental Study on Pediatric Single Eccentric Screw Blood Pump”, Turbomachinery, vol. 43(2015), No.4 pp.222-228

[4] Yeh, Yee Cheng, Naoya Yamada, Yosuke Watanabe, MD Nahin Islam Shiblee, Jun Ogawa, Ajit Khosla, Masaru Kawakami, Teruaki Akamatsu, and Hidemitsu Furukawa. “3D Printing of Soft-Matter Mono Pump in Infant Ventricular Assist Device (VAD) for Blood Pumping” ECS Transactions 98, no. 13 (2020): 31.