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The parallel displacement transfer pump, also known as a parallel pump or translational pump, is designed specifically for transporting materials that are highly sensitive to shear forces, as well as high-viscosity materials and materials containing many particles. It is a positive-displacement pump that can be used with a wide range of viscous materials under various process conditions and production scenarios. It is fully capable of the stable transportation of mixed heterogeneous phases such as gas-liquid and solid-liquid. Parallel pumps feature an open, modular design, making them easy to install and maintain. The entire pump system consists of three main components: the pump body, the drive gearbox, and the drive motor. The parallel pump is a fully stainless-steel sanitary pump; all parts in contact with the material are made of high-quality 316 stainless steel, while the other parts are made of 304 stainless steel. The inner surface of the material passage has been subjected to special mechanical and electro-polishing treatments. It features a silicon carbide-based double-end face mechanical seal. The pump body is the core component, and it consists of a self-priming negative-pressure feed chamber, a loss-free material transfer chamber, parallel rotors, a high-pressure discharge chamber, dual mechanical seal chambers, and a high-strength drive shaft. The drive shaft features a robust and reinforced design with a monolithic structure; it is made of high-strength special precipitation-hardening stainless steel that has undergone solution treatment and hardening. The transmission gear box consists of a driving shaft and a driven shaft; each shaft is equipped with paired bearings and gears. Synchronous gears are high-precision synchronous helical gears rather than straight gears. The transmission bearings are of high strength, high performance, and long-lasting design. The gear box features a specially designed vibration-damping, heat-disipation, and lubrication system that ensures smoother and quieter operation of the equipment, while also helping to withstand various unexpected conditions and extend its service life. Tips for selecting parallel pumps: The viscosity of the medium has a significant impact on the performance of parallel pumps. The nominal flow rate of a pump refers to the flow rate under specific viscosity conditions; to ensure that the pump operates at high efficiency, it is essential to determine all relevant performance parameters accurately. Selection of performance parameters: Flow rate Q: As a positive displacement pump, the main factors affecting its flow rate are the rotational speed n, pressure p, and the viscosity v of the medium. All these factors must be considered comprehensively; only through a series of calculations can we accurately determine whether the actual flow rate of the pump meets the requirements of the operating conditions. Pressure P: Unlike centrifugal pumps, the operating pressure of parallel pumps is determined by the outlet load, that is, by the outlet resistance. The outlet resistance matches the pressure at the pump’s outlet; the greater the outlet resistance, the higher the operating pressure. To determine the pressure, it is necessary to use knowledge of fluid mechanics to accurately calculate the outlet resistance. Shaft power N: The shaft power of a parallel pump is divided into two parts, namely: Nth – hydraulic power, which is the energy of the pressurized liquid ； For a given pressure and flow rate, the frictional power is constant, and thus the hydraulic power remains fixed; therefore, the factor that affects the shaft power is the frictional power. Friction power is the portion of power consumed due to the friction between moving parts. These friction powers clearly increase as the working pressure difference increases, and an increase in the viscosity of the medium also leads to an increase in the liquid’s friction power. Therefore, in addition to the hydraulic power, the shaft power of the pump also includes frictional power, which increases with the viscosity of the medium and the operating pressure; thus, when selecting a suitable motor, the viscosity of the medium is also a very important factor to consider. Especially when transporting high-viscosity media, relatively precise calculations are required. Suction performance: The operation of the pump goes through the following stages: Suction: At this stage, the liquid moves continuously along the suction pipe ； The rotating rotor transfers energy to the working fluid ； Extraction: At this point, the liquid is discharged from the pump at a pressure sufficient to overcome all the resistances in the extraction pipeline system. Of the above three stages, the most important one is ensuring the suction conditions for the pump, as this is essential for its proper operation. It is a critical requirement for pump functioning; otherwise, cavitation will occur, leading to problems such as vibration and noise. Net Positive Suction Head: The pump’s Net Positive Suction Head required (NPSHr) is related to factors such as the pump’s rotational speed n, pitch h, and the viscosity v of the fluid being pumped. Selection of rotation speed for parallel pumps: Changes in the viscosity of the medium are the main factor determining the rotation speed; as viscosity increases, the allowable rotation speed decreases as well. As the viscosity changes, the pump speed should also change accordingly. By selecting the appropriate speed, suitable performance parameters such as flow rate can be achieved. The selection of rotational speed is essentially a matter of suction performance, especially in cases involving high viscosity. If the rotational speed is set too high, it can lead to insufficient suction, resulting in problems such as noise and vibration. Therefore, it is essential to select the rotational speed in accordance with relevant principles. Functional features of the parallel pump: it can convey not only materials with medium to high viscosity, but also those with low viscosity ； The conveying direction is the same as the material flow direction; it causes no damage or agitation to the material, generates lower shear forces, and can convey materials containing particles of various sizes ； High head, large flow rate; pressure ranges from 6 to 50 bars, and flow rate can reach up to 300 m³/h. It has excellent self-priming capability, with a negative pressure of up to -0.98 bar ； Continuous and uniform flow, minimal vibration, low noise ； No rotor-spindle structure, simplifying subsequent maintenance ； Water ring double-end mechanical seal, leak-free, long service life ；