An Analysis of the Core Structural Components of Centrifugal Pumps

TEFFIKO, a highly regarded brand in the industry, has always been dedicated to the in - depth exploration and innovation in the field of centrifugal pumps. In the industrial sector, centrifugal pumps are crucial fluid - conveying equipment, widely used in various industries. Their reliable operation depends on several key structural components.

Impeller: The Power Source

The impeller is the core component of a centrifugal pump, much like the engine of a car. It is composed of multiple curved blades, usually with a backward - curved design, and the blade angle ranges from 30° to 40°. This structure can optimize the pump's efficiency. When the impeller rotates at a high speed, its blades drive the liquid. Under the action of centrifugal force, the liquid is thrown from the center of the impeller to the edge, thus obtaining high speed and kinetic energy.

The material selection of the impeller is of great significance. For regular applications, 304 stainless steel is sufficient as it has certain corrosion resistance and mechanical strength to meet the requirements. However, in harsh chemical environments such as chemical manufacturing, Duplex 2205 duplex stainless steel is more favored. It has a relatively high pitting resistance equivalent number (PREN > 35), which can resist severe corrosion and ensure the smooth operation of the impeller.

Volute: The Energy Conversion Center

The volute, shaped like a snail shell, plays a key role in converting the kinetic energy of the liquid into pressure energy. When the high - speed liquid thrown out from the impeller enters the volute, as the flow - passage area of the volute gradually increases, the liquid flow rate gradually decreases. According to the law of conservation of energy, the reduction in kinetic energy leads to an increase in pressure energy.

Compared with other types of pump casings, the volute can increase the pump's efficiency by 7% to 12%. Under normal operating conditions, cast iron is a common choice due to its low cost and ability to meet basic functional requirements. However, when dealing with corrosive media, super duplex stainless steel that meets the NACE MR0175 standard is used to ensure long - term stable operation.

Shaft Assembly: The Guarantee of Stable Operation

The shaft assembly connects the impeller and the driving device and is crucial for the stable operation of the centrifugal pump. It is usually made of ASTM A479 stainless steel, which has good mechanical properties and corrosion resistance. The shaft not only has to bear the weight of the impeller but also the torque generated by rotation. At the same time, it must maintain high - precision rotation. To ensure efficient operation, its rotation tolerance is controlled below 0.005 mm.

In extreme conditions such as high - temperature, high - pressure, or strong corrosion, high - performance alloys like Inconel 625 are used. Its yield strength is as high as 125 ksi, which can prevent the shaft from deforming and being damaged, ensuring the reliable operation of the pump.

Sealing System: The Leak - Proof Barrier

The sealing system is an important defense line for centrifugal pumps to prevent liquid leakage and the intrusion of external impurities. Traditional packing seals have certain limitations in sealing performance and service life. Most modern centrifugal pumps use mechanical seals, and their service life can exceed 25,000 hours.

A mechanical seal consists of components such as a moving ring, a stationary ring, and elastic elements. It prevents leakage through the close fit of the moving ring and the stationary ring. In high - risk scenarios such as transporting toxic or flammable liquids, double - seal systems with flushing devices are used. For sealing materials, carbon/ceramic is suitable for general situations, while in more demanding working conditions, materials such as silicon carbide (SiC) are used to ensure reliability.

In conclusion, the impeller, volute, shaft assembly, and sealing system are all indispensable for centrifugal pumps. TEFFIKO always adheres to carefully selecting and maintaining these components according to specific working conditions to achieve the best performance of the pump and ensure the smooth progress of industrial production. If you have any needs, you can contact us at any time.