Pipeline pumps, as crucial components in fluid delivery systems, rely on the synergy of various parts for their proper operation and performance. The sealing device is particularly critical, serving as the "gatekeeper" of the pump, safeguarding the fluid world inside and outside the pump body to ensure no leakage occurs, thus maintaining the stable operation of the entire system. Understanding the working principles of pipeline pumps and delving into the types and working principles of their sealing devices is of significant importance for us to better utilize and maintain pipeline pumps.

Stuffing Seal: This is a common sealing method in pipeline pumps. It utilizes packing material (such as graphite, asbestos, etc.) to form a seal between the shaft and the packing box. By compressing the packing material, it snugly fits against the shaft, preventing medium leakage. Stuffing seal has a simple structure, is inexpensive, and easy to maintain. However, it tends to have a larger leakage volume and higher consumption losses, thus generally suitable for transporting general media such as water. In petroleum, chemical media, especially valuable, volatile, and toxic media, stuffing seals are usually not applicable.

Mechanical Seal: Mechanical seal (also known as end-face seal) is another important sealing method. It consists of a rotating ring (moving ring) and a stationary ring (static ring), with the end faces of the two rings tightly fitted together and relative rotation forming a sealed end face. Mechanical seals have excellent sealing effects, minimal leakage, long service life, but relatively higher prices, and higher requirements for processing, installation, maintenance, and upkeep compared to general seals. They are suitable for transporting petroleum and chemical media and can also be used for various media with different viscosities, strong corrosiveness, and particle content.

Dynamic Seal: Dynamic seals can be divided into back vane seals and impeller seals. This sealing method utilizes the dynamic characteristics of the pump to achieve sealing effects through specific structural designs.

Through an in-depth exploration of the sealing devices in pipeline pumps, it's evident that both traditional stuffing seals and efficient mechanical seals play irreplaceable roles in their respective application areas. Each sealing device has its unique advantages and suitable scenarios, making the selection of the appropriate sealing device crucial for ensuring the safe and stable operation of pipeline pumps.