Combined sealing structure for stuffing box of axial flow pump

Abstract

The utility model relates to an axial flow pump stuffing box combined type sealing structure which comprises a gland, a stuffing box body, an oil injection nozzle and a separation ring, the gland is connected with the stuffing box body through a bolt, an upper inner flanging and a lower inner flanging are correspondingly formed on the inner sides of the upper end and the lower end of the gland, and the separation ring is located in the middle of the inner ring wall of the gland. A first J-shaped sealing piece is clamped between the upper inner flanging and the upper end of the separation ring, a second J-shaped sealing piece and a third J-shaped sealing piece which are stacked up and down and arranged back to back are clamped between the lower inner flanging and the lower end of the separation ring, an oil injection channel penetrating up and down is formed in the separation ring, and the oil injection nozzle is connected to the outer wall of the gland and communicated with the oil injection channel. The packing box has the advantages that the first J-shaped sealing piece, the second J-shaped sealing piece and the third J-shaped sealing piece are arranged from top to bottom, three seals are formed, the sealing effect is good, lubricating grease can be injected into the J-shaped sealing pieces in the packing box through the oil injection nozzles to reduce the friction effect and form oil seals, after the lubricating grease is lost, the lubricating grease can be supplemented through the oil injection nozzles, disassembly and maintenance are not needed, and maintenance is convenient.

Description

Technical Field

[0001] The utility model belongs to the field of water pump sealing structures, and in particular relates to an axial flow pump stuffing box combined sealing structure. Background Art

[0002] The main function of the pump stuffing box is to form a seal at the position where the pump shaft passes through the pump casing to prevent the working medium of the pump from leaking and ensure the sealing performance and normal operation of the pump. The stuffing box is usually cylindrical in shape and fits the pump body. The stuffing box is filled with stuffing, which is the sealing material between the medium and the pump shaft (such as oil-impregnated asbestos rope). Conventional stuffing seal structures are as follows: Figure 1 As shown, the sealing packing 1A is sealed in the stuffing box body by a packing gland. This structure can provide a good sealing effect for a certain period of time, but as the use time increases, the sealing packing will gradually disappear or age and deform, resulting in an obvious gap between the pump shaft and the sealing packing, causing water leakage. Utility Model Content

[0003] The utility model provides an axial flow pump stuffing box combined sealing structure, aiming to overcome the problem of poor sealing effect and water leakage in conventional stuffing sealing structures in the prior art as the service time increases.

[0004] The utility model solves the above-mentioned technical problems with a technical solution as follows: a combined sealing structure of an axial flow pump stuffing box, comprising a gland, a stuffing box body, an oil injection nozzle and a separator ring, the gland is connected to the stuffing box body by bolts, the upper and lower ends of the gland are correspondingly formed with upper inner flanges and lower inner flanges on the inner sides, the separator ring is located in the middle of the inner ring wall of the gland, a first J-type seal is sandwiched between the upper inner flange and the upper end of the separator ring, a second J-type seal and a third J-type seal stacked up and back to back are sandwiched between the lower inner flange and the lower end of the separator ring, an oil injection channel running through the separator ring from top to bottom is provided in the separator ring, the oil injection nozzle is connected to the outer wall of the gland and communicated with the oil injection channel, and the sealing lips of the first J-type seal, the second J-type seal and the third J-type seal are all interference fit with the pump shaft sleeve.

[0005] On the basis of the above technical solution, the present invention can also be improved as follows.

[0006] Furthermore, the first J-type seal and the third J-type seal are both placed with their sealing lips downward, and the second J-type seal is placed with its sealing lip upward.

[0007] Furthermore, oil inlets are correspondingly provided on the side walls of the gland and the separation ring, and the oil inlets are connected to the oil injection nozzle and the oil injection channel.

[0008] Furthermore, the separation ring is integrally formed or formed by splicing multiple arc-shaped blocks.

[0009] Furthermore, the upper inner flange is detachably connected to the upper end of the gland by means of bolts or a pressure plate arranged above.

[0010] Furthermore, the separation ring is clearance-matched with the shaft sleeve.

[0011] Compared with the prior art, the beneficial effects of the utility model are:

[0012] A total of three J-shaped seals, the first to the third, are arranged in the stuffing box from top to bottom to form three seals with good sealing effect. The oil injection nozzle can inject lubricating grease into the J-shaped seal in the stuffing box through the oil injection port and the oil injection channel on the pressure cover and the side wall of the separation ring to reduce friction and form an oil seal. When the lubricating grease is lost, it can be supplemented through the oil injection nozzle without disassembly and maintenance. The maintenance is convenient and has a longer-lasting sealing effect than the conventional sealing packing seal. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 A schematic diagram of a conventional sealing structure using sealing packing;

[0014] Figure 2 A schematic diagram of the combined sealing structure of the axial flow pump stuffing box provided by the utility model;

[0015] Figure 3 for Figure 2 A top view of the combined sealing structure shown;

[0016] Figure 4 for Figure 2 An enlarged view of the oil filling nozzle and the structure within the dotted circle in the combined sealing structure shown.

[0017] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0018] 1. Gland; 2. Stuffing box body; 3. Oil injection nozzle; 4. Separation ring; 5. First J-type seal; 6. Second J-type seal; 7. Third J-type seal; 8. Bushing; 9. Oil injection channel; 1A. Sealing packing. DETAILED DESCRIPTION

[0019] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0020] In the description of the present invention, if terms indicating orientation such as "up", "down", "left", "right", "top", "bottom", "inside" and "outside" are used, the orientation or position relationship indicated is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0021] like Figure 1 As shown, currently, a conventional packing seal structure is generally used for the pump shaft extending out of the pump casing. In this structure, the sealing packing 1A is sealed in the stuffing box by the packing gland, and a mechanical seal is formed between the sealing packing and the shaft sleeve. The sealing effect can meet the requirements for a certain period of time, but as the sealing packing ages or loses, a water leakage gap will be formed between the shaft sleeve and the sealing packing, and the seal will fail.

[0022] like Figures 2 to 4 As shown, the utility model provides an axial flow pump stuffing box combined sealing structure, which includes a gland 1, a stuffing box body 2, an oil injection nozzle 3 and a separator ring 4, the gland 1 is connected to the stuffing box body 2 by bolts, the upper end and the lower end of the gland 1 are formed with upper inner flanges and lower inner flanges on the inner side respectively, the separator ring 4 is located in the middle of the inner ring wall of the gland 1, a first J-type seal 5 is sandwiched between the upper inner flange and the upper end of the separator ring 4, a second J-type seal 6 and a third J-type seal 7 stacked up and down and arranged back to back are sandwiched between the lower inner flange and the lower end of the separator ring 4, an oil injection channel 9 running through the separator ring 4 from top to bottom is provided, the oil injection nozzle 3 is connected to the outer wall of the gland 1 and communicated with the oil injection channel 9, and the sealing lips of the first J-type seal 5, the second J-type seal 6 and the third J-type seal 7 are all interference fit with the pump shaft sleeve 8.

[0023] It should be noted that the first to third J-type seals are all commercially available standard parts, which generally include a hard plastic ring body and an elastic sealing lip arranged in the ring body. The inner side of the elastic sealing lip is usually also provided with an annular spring ring to keep it close to the outer wall of the sleeve. The specific structure and specifications are not elaborated here.

[0024] It is understandable that, if necessary, more J-type seals can be set on the inner side of the pressure cover. The setting and placement of the above-mentioned first to third J-type seals are a form with better sealing effect and relatively low cost. Other structural forms for placing more J-type seals can also be selected according to actual conditions.

[0025] In one embodiment of the present invention, the first J-shaped seal 5 and the third J-shaped seal 7 are both placed with the sealing lips facing downward, and the second J-shaped seal 6 is placed with the sealing lips facing upward.

[0026] It should be noted that the back-to-back arrangement of the second and third J-shaped seals can allow a certain spacing distance between the sealing lips of the two, so that there will be no adverse interaction between them, and a better sealing effect can be achieved by appropriately spacing the two seals at a certain distance.

[0027] In one embodiment of the present utility model, oil inlets are correspondingly opened on the side walls of the gland 1 and the separation ring 4 , and the oil inlets are connected to the oil injection nozzle 3 and the oil injection channel 9 .

[0028] It should be noted that in order to make the oil injection flow smoother and reduce the trouble of holes during installation, the oil inlet on the separator ring can be arranged to go around the separator ring for one circle or more than half a circle.

[0029] In one embodiment of the utility model, the separator ring 4 is integrally formed or formed by splicing multiple arc-shaped blocks. The separator ring formed by splicing multiple arc-shaped blocks has the effect of replacing only the severely worn blocks during maintenance, thereby reducing costs.

[0030] In one embodiment of the utility model, the upper inner flange is detachably connected to the upper end of the gland 1 by bolts or a pressure plate arranged above.

[0031] It should be noted that the upper inner flange is configured to be detachable relative to the gland, which facilitates the installation of the first to third J-shaped sealing rings and separator rings and subsequent maintenance and replacement.

[0032] In the above-mentioned embodiments, the separation ring 4 and the shaft sleeve 8 are clearance-matched to avoid direct friction between the shaft sleeve and the inner wall of the separation ring.

[0033] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An axial flow pump stuffing box combined sealing structure, characterized in that: The invention comprises a gland (1), a stuffing box body (2), an oil injection nozzle (3) and a separator ring (4); the gland (1) is connected to the stuffing box body (2) by bolts; the upper end and the lower end of the gland (1) are formed with an upper inner flange and a lower inner flange on the inner side respectively; the separator ring (4) is located in the middle of the inner ring wall of the gland (1); a first J-shaped seal (5) is sandwiched between the upper inner flange and the upper end of the separator ring (4); a second J-shaped seal (6) and a third J-shaped seal (7) are sandwiched between the lower inner flange and the lower end of the separator ring (4) and are stacked up and down and arranged back to back; an oil injection channel (9) is provided in the separator ring (4) and runs through the oil injection channel (9); the oil injection nozzle (3) is connected to the outer wall of the gland (1) and communicates with the oil injection channel (9); the sealing lips of the first J-shaped seal (5), the second J-shaped seal (6) and the third J-shaped seal (7) are all interference fit with the pump shaft sleeve (8).

2. The axial flow pump stuffing box combined sealing structure according to claim 1 is characterized in that: The first J-shaped seal (5) and the third J-shaped seal (7) are both placed with their sealing lips facing downwards, while the second J-shaped seal (6) is placed with its sealing lips facing upwards.

3. The axial flow pump stuffing box combined sealing structure according to claim 1, characterized in that: Oil inlets are correspondingly provided on the side walls of the gland (1) and the separation ring (4), and the oil inlets are connected to the oil injection nozzle (3) and the oil injection channel (9).

4. The axial flow pump stuffing box combined sealing structure according to claim 1, characterized in that: The separation ring (4) is integrally formed or is formed by splicing multiple arc-shaped blocks.

5. The axial flow pump stuffing box combined sealing structure according to claim 1, characterized in that: The upper inner flange is detachably connected to the upper end of the gland (1) via bolts or a pressure plate arranged above.

6. An axial flow pump stuffing box combined sealing structure according to any one of claims 1 to 5, characterized in that: The separation ring (4) and the shaft sleeve (8) are clearance-matched.

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