In industries such as chemical, petroleum, and power, centrifugal pumps are core equipment for fluid transportation. The mechanical seal, as a crucial component of centrifugal pumps to prevent medium leakage and ensure equipment safety, directly affects the efficiency, lifespan of the centrifugal pump, and the safety of production.
A centrifugal pump mechanical seal mainly consists of a rotating ring, a stationary ring, elastic elements, and auxiliary sealing rings. The rotating ring rotates with the pump shaft, while the stationary ring is fixed to the pump body. The elastic elements provide a pre - tightening force to keep the two rings in close contact, and the auxiliary sealing rings prevent leakage from non - sealing surfaces. During operation, the rotating and stationary rings rotate relative to each other. Under the action of the pre - tightening force and medium pressure, a liquid film is formed between the sealing surfaces. This liquid film not only lubricates and reduces wear but also prevents medium leakage.
A single - end face mechanical seal has only one pair of sealing surfaces. It features a simple structure, low cost, and easy maintenance. However, its sealing ability is limited, and it is suitable for scenarios where the medium pressure and temperature are not high and the sealing requirements are relatively low, such as clean water transportation.
A double - end face mechanical seal has two pairs of sealing surfaces. By introducing an isolation liquid, a buffer chamber is formed, enabling it to handle high - pressure and harsh working conditions. It is commonly used for transporting dangerous media such as flammable, explosive, and toxic substances. Nevertheless, its structure is complex, and installation, maintenance are difficult and costly.
A multi - spring mechanical seal uses multiple small springs. It has a uniform sealing specific pressure and strong adaptability to shaft vibration, making it suitable for high - speed centrifugal pumps. However, attention should be paid to the spring compression and uniformity during installation.
Factors such as wear of the sealing surface, improper installation, impurities in the medium, and high temperature can all lead to the most common problem of sealing surface leakage.
Reasons such as incorrect material selection, installation damage, and aging can cause the failure of the auxiliary sealing ring, resulting in leakage.
Issues like poor corrosion resistance of the spring material, plastic deformation, and the influence of environmental temperature can cause the spring to fail, leading to insufficient pre - tightening force on the sealing surface.
During daily operation, it is necessary to check the leakage volume, temperature, and operating sound of the sealing part. Regularly disassemble and clean the mechanical seal. Depending on the degree of wear of the sealing surface, choose to repair or replace it. Timely replace aging sealing rings and failed springs, and strictly follow the procedures during installation. At the same time, properly manage the medium, install filters to intercept particulate impurities, and control the medium temperature and pressure within the allowable range of the seal.
The performance of centrifugal pump mechanical seals is related to the stability and reliability of centrifugal pump operation. Mastering its structural principles, type characteristics, fault causes, and maintenance methods helps to ensure the efficient operation of centrifugal pumps, reduce production risks, and promote the safe and stable development of industrial production.
If you have any questions, you can contact TEFFIKO. We will provide you with professional and detailed answers, supplement the information you need, and help you better master the technical key points of centrifugal pump mechanical seals.
