How does a progressive cavity pump reduce pulsation during fluid transmission?

In the process of industrial fluid transmission, pulsation can cause unstable flow, which in turn affects the working efficiency and service life of the equipment. Progressive cavity pumps (such as Equal Wall Thickness Screw Pumps) can effectively reduce pulsation and achieve smooth fluid transmission due to their unique design. This article will discuss the working principle, design features and specific advantages of progressive cavity pumps in reducing pulsation.

1. Working principle of progressive cavity pumps
The core components of progressive cavity pumps are rotors and stators.

Rotor: Usually a screw with a large lead, high tooth height and small spiral diameter, its geometric design ensures a smooth motion trajectory.
Stator: A double-thread or triple-thread spiral sleeve that matches the rotor, and its equal wall thickness design ensures uniform delivery of the medium.
When the rotor rotates, multiple closed cavities are formed between the stator and the rotor. The fluid moves from the suction end through these cavities gradually to the discharge end, forming a stable axial flow.

2. Design features to reduce pulsation
2.1 Closed cavity design
The progressive cavity pump forms a uniform and continuous closed cavity through the precise cooperation between the rotor and the stator. The volume of each cavity remains constant during the rotation of the rotor, thus avoiding sudden changes in flow and greatly reducing pulsation.

2.2 Progressive delivery
The design of the pump allows the fluid to be gradually transferred from one cavity to the next. Compared with the intermittent delivery of other pumps (such as plunger pumps), this progressive fluid delivery method can achieve continuity and stability of flow.

2.3 Double-threaded or triple-threaded stator
The design of the multi-threaded stator allows more cavities to be transferred per unit time, further smoothing the flow fluctuations and reducing the amplitude of periodic pulsation.

2.4 Equal wall thickness stator design
The equal wall thickness stator not only makes the rubber stress distribution more uniform, but also reduces pressure fluctuations when the cavity is switched. This design is particularly suitable for scenarios that require high-precision flow control.

3. Advantages of reducing pulsation
3.1 Improving fluid delivery stability
Due to the reduction of fluid pulsation, the progressive cavity pump can provide constant flow and pressure output, which is suitable for applications such as precision machining and metering delivery that require stable flow.

3.2 Reducing equipment vibration and noise
Pulsation often causes vibration and noise in the equipment, while the smooth delivery of the progressive cavity pump effectively reduces these problems, thereby improving the reliability and comfort of equipment operation.

3.3 Prolonging equipment service life
Reducing pulsation means that the pressure fluctuations on the pump and pipeline system are reduced, which helps to reduce the wear of parts and extend the service life of the pump and related equipment.

4. Application scenarios
Progressive cavity pumps are widely used in the following fields due to their excellent smooth delivery ability:

Food processing: conveying high-viscosity media such as jam and dairy products to ensure the consistency of product quality.

Chemical industry: When conveying sensitive chemicals, reducing pulsation can avoid medium stratification or chemical reactions.

Oil and gas extraction: used to convey crude oil containing sand or solid particles to ensure smooth operation of equipment.