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I. Improve the shaft seal structure: To address the issue of excessive gap between the outer hole of the original packing gland and the shaft, the shape of the outer part of the packing gland was modified. Adopt an outer constricted aperture to retain the liquid ejected from the shaft seal ； Methods such as drilling a through-hole in the middle of the wide surface of the packing seal gland can be used (place the side with the through-hole on the bottom during assembly). Let’s refer to Figure 1 instead. http://img.pmec.net/200708/2517801.gif 1. Reduce the gap between the gland and the shaft: Add an annular step at this diameter to decrease the gap between the hole and the shaft, keeping this gap within the range of 0.2–0.3 mm. A vertical hole is drilled on the outer side of the middle part of the packing gland, whose purpose is to direct the liquid trapped in the annular space inside the gland to the lower side of the packing chamber. 2. Change the cone angle of the gland end face: By altering the cone angle of the inner end face of the gland, the contact area between the gland and the fiber packing is increased, thereby preventing the fiber packing from rotating. II. Replacing the pump’s liquid seal ring: In some centrifugal pumps, the inlet is filled with high-pressure liquid; in other cases, the liquid flowing through the suction holes in the stuffing box can cause corrosion, leading to an increase in the diameter of these holes. Additionally, when multiple pumps operate in parallel, it is easy for high-pressure liquid to enter the stuffing box, thereby increasing the leakage from the pump. To address this issue, the liquid seal components in the filler chamber were modified, changing the original liquid seal ring, which served to guide the liquid, into one that functions as a seal. After the sealing ring is installed, the amount of high-pressure liquid entering the packing chamber is reduced, thereby eliminating the need to over-compress the packing gland and lowering the friction between the fiber packing and the pump shaft. This improvement can reduce mechanical losses and extend the service life of the fiber filler. It is estimated that a centrifugal pump will use 30%–40% less fiber packing per year, and the shaft sleeves made of ordinary cast iron will need to be replaced less frequently each year, which also reduces the amount of maintenance work required. Improvements are shown in Figure 2. http://img.pmec.net/200708/2517802.gif The gap between the outer diameter of the sealing ring and the hole in the packing chamber is 0.1–0.15 mm. The dimensions of the two grooves are based on the diameter of the O-ring’s cross-section, being slightly smaller than that dimension. After installing the O-rings, the outer diameter should be slightly larger than the outer diameter of the sealing ring by 0.2–0.3 mm, so that once the sealing ring is placed inside the hole in the packing chamber, the O-rings on both sides can seal off the liquid in the liquid guide holes. The sealing ring should be 6–10 mm wider than the liquid seal ring, to prevent excessive axial movement of the sealing ring when adjusting the packing gland, which could cause the O-ring to miss its position in the liquid seal hole and thus lose its function. III. Regular inspection and management of the packing gland: The gap between the new packing gland hole and the pump shaft should be 0.2 mm. During maintenance, it is essential to ensure the proper installation of the packing gland; an inclined gland can cause friction between the inner hole and the pump shaft sleeve. In daily maintenance, it is necessary to regularly check the fluid guide holes at the lower end of the packing gland to ensure they remain unobstructed. The shaft seal components of centrifugal pumps need to be cleaned and protected against corrosion on a regular basis, especially in the case of hot water pumps and sewage pumps, as the shaft seal parts are prone to rusting. This can result in an inability to adjust the gland. If these components are not made of stainless steel, the studs and nuts used to secure the packing gland must be replaced regularly; otherwise, rusting between these components and those of the packing chamber can lead to malfunctions. Different models of pumps use different materials and have various shapes, but the structure of the packing seal components in pumps remains unchanged. It is hoped that the production department will manufacture a small quantity of new gland seals, or produce gland seals made from different materials for the users to choose from, so as to reduce waste.