An airtightness testing device for a single-end mechanical seal

Abstract

This utility model provides an airtightness testing device for a single-end mechanical seal, belonging to the field of petrochemical plant construction. The device includes an air pump, a pressure gauge, a top cover, a mechanical seal, a nylon short shaft, a pressure plate, a crossbeam, a sealing cylinder, and a base. The mechanical seal is mounted on the top cover of the sealing cylinder, and the nylon short shaft is located at the upper end of the mechanical seal. The crossbeam is mounted on the base via supporting adjusting bolts, and is positioned directly above the sealing cylinder. The upper end of the pressure plate is mounted on the crossbeam, and the lower end of the pressure plate is located on the upper surface of the mechanical seal. The pressure gauge is mounted on the base and connected to the air pump. This utility model solves the problem that conventional methods cannot perform external pressure testing on the pump body before installation due to the different structural forms of single-end mechanical seals.

Description

Technical Field

[0001] This utility model belongs to the field of petrochemical plant construction, and specifically relates to a device for testing the airtightness of a single-end mechanical seal. Background Technology

[0002] During the construction of petrochemical plants, pump sealing devices include several types such as packing seals, tandem mechanical seals, double-end mechanical seals, and single-end mechanical seals. Packing seals have been largely phased out in refining and chemical plants.

[0003] Tandem mechanical seals and double-end mechanical seals are relatively easy to pressure test before maintenance and replacement to check their sealing effect. However, due to their different structural form, single-end mechanical seals cannot be pressure tested outside the pump body before installation using conventional methods.

[0004] Publication No. CN107192504A discloses a hydrostatic testing fixture for inspecting the pressure-bearing capacity and airtightness of machine body parts. The machine body parts are equipped with cylinder bore sealing devices that seal the upper and lower ends of the cylinder bores. Multiple flange sealing devices, corresponding to and sealing the water and air chamber openings, are located on the side walls of the machine body parts. Oil hole sealing devices are also provided on the machine body parts, sealing the oil holes on the side walls and left and right end faces, as well as the open oil holes inside the machine body parts. A venting device is connected to the cylinder bore and, after being connected to a quick-change hydrostatic testing unit, the pressure-bearing capacity and airtightness of the machine body parts are inspected through water injection, pressurization, and pressure holding. This invention utilizes a hydrostatic testing fixture to ensure the pressure-bearing capacity and airtightness of the water chamber, lubricating oil chamber, and various oil passages of machine body parts. It provides good sealing, high safety, and convenient disassembly and assembly during hydrostatic testing, improving the quality and efficiency of hydrostatic testing of machine body parts. It has a wide range of applications and is easy to promote and apply. Its structure is relatively complex and it is not suitable for airtightness tests of single-end mechanical seals for pumps. Utility Model Content

[0005] To overcome the problem that conventional methods cannot perform external pressure testing on the pump body before installation due to the different structural forms of existing single-end mechanical seals, this utility model provides an airtightness testing device for single-end mechanical seals. This utility model uses bolts installed in the bolt holes to fix the mechanical seal and the pressure plate to the upper cover, and pressurizes the sealing cylinder with an air pump to test the sealing performance of the mechanical seal. This improves the convenience of installation and disassembly when testing the airtightness of the mechanical seal.

[0006] The technical solution provided by this utility model is as follows:

[0007] An airtightness testing device for a single-end mechanical seal includes an air pump, a pressure gauge, a top cover, a mechanical seal, a nylon short shaft, a pressure plate, a crossbeam, a sealing cylinder, and a base. The mechanical seal is mounted on the top cover of the sealing cylinder, and the upper end of the mechanical seal has a nylon short shaft. The crossbeam is mounted on the base via support adjusting bolts, and the crossbeam is located directly above the sealing cylinder. The upper end of the pressure plate is mounted on the crossbeam, and the lower end of the pressure plate is located on the upper surface of the mechanical seal. The pressure gauge is mounted on the base and is connected to the air pump.

[0008] The pressure plate consists of two pieces, each of which is a long rectangular block. One end of the long rectangular block has a horizontal through groove, through which a crossbeam passes.

[0009] The sealing cylinder is welded to the base as a single unit.

[0010] A filter is provided between the pressure gauge and the air pump, and valves are provided at both ends of the filter.

[0011] A pressure reducing valve is provided between the pressure gauge and the filter.

[0012] The top cover is provided with a sealing groove and a positioning groove.

[0013] The maximum outer diameter of the top cover is greater than the maximum outer diameter of the sealing cylinder.

[0014] Four casters are installed under the base.

[0015] The air pump mentioned is a miniature air pump.

[0016] The upper end of the nylon short shaft is connected to the crossbeam by a short shaft bolt.

[0017] The beneficial effects of this utility model are as follows:

[0018] This invention provides an airtightness testing device for a single-end mechanical seal. The mechanical seal and pressure plate are fixed to the upper cover via bolt holes. The sealing cylinder is pressurized using an air pump to test the seal's tightness. This invention is easy to disassemble, assemble, or manufacture; it is small in size and easy to carry, allowing for convenient testing and inspection at construction sites.

[0019] This invention solves the problem of air source limitation by using a miniature air pump. By adding a filter and a pressure reducing valve, it ensures the cleanliness and pressure accuracy of the compressed air entering the mechanical seal, eliminating the damage to the mechanical seal caused by unclean air source and overpressure during the inspection process.

[0020] The air tightness test device for single-end mechanical seals of pumps provided by this utility model solves the problem that conventional methods cannot perform external pressure testing on single-end mechanical seals before installation due to their different structural forms.

[0021] This invention has a simple structure, is easy to operate, provides good sealing test results, and can improve test efficiency.

[0022] The following will provide further explanation in conjunction with the accompanying drawings. Attached Figure Description

[0023] Figure 1 This is the main structural view of this utility model.

[0024] Figure 2 This is a side view of the structure of this utility model.

[0025] Figure 3 Top view of the structure of this utility model.

[0026] Figure 4 This is a three-dimensional structural diagram of the present invention.

[0027] Figure 5 yes Figure 3 BB section view.

[0028] Figure 6 yes Figure 1 FF sectional view.

[0029] Figure 7 A schematic diagram of the sealing groove opened at the mechanical seal.

[0030] In the figure, the attached figures are labeled as follows:

[0031] 1. Air pump; 2. Valve; 3. Filter; 4. Pressure reducing valve; 5. Pressure gauge; 6. Top cover; 7. Mechanical seal; 8. Nylon short shaft; 9. Pressure plate; 10. Crossbeam; 11. Short shaft bolt; 12. Sealing cylinder; 13. Support adjusting bolt; 14. Base; 15. Sealing groove; 16. Positioning groove. Detailed Implementation

[0032] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0033] The accompanying drawings show various structural schematic diagrams according to embodiments of the present invention. These drawings are not to scale, and some details have been enlarged and may have been omitted for clarity. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0034] Example 1:

[0035] To overcome the problem that conventional methods cannot perform external pressure testing on the pump body before installation due to the different structural forms of existing single-end mechanical seals, this utility model provides... Figure 1-7 The invention relates to a single-end mechanical seal airtightness testing device. The mechanical seal mating pressure plate is fixed to the upper cover by bolts installed in the bolt holes. The sealing cylinder is pressurized by an air pump to test the airtightness of the mechanical seal. This improves the convenience of installation and disassembly when testing the airtightness of the mechanical seal.

[0036] An airtightness testing device for a single-end mechanical seal includes an air pump 1, a pressure gauge 5, a top cover 6, a mechanical seal 7, a nylon short shaft 8, a pressure plate 9, a crossbeam 10, a sealing cylinder 12, and a base 14. The mechanical seal 7 is mounted on the top cover 6 of the sealing cylinder 12, and the upper end of the mechanical seal 7 is provided with the nylon short shaft 8. The crossbeam 10 is mounted on the base 14 via a support adjusting bolt 13, and the crossbeam 10 is located directly above the sealing cylinder 12. The upper end of the pressure plate 9 is mounted on the crossbeam 10, and the lower end of the pressure plate 9 is located on the upper surface of the mechanical seal 7. The pressure gauge 6 is mounted on the base 14, and the pressure gauge 5 is connected to the air pump 1.

[0037] In this invention, during the mechanical seal sealing test, a bolt hole is provided at the center of the crossbeam 10. A short shaft bolt 11 passes downward through this bolt hole, fixing the mechanical seal 7 and pressure plate 9 to the upper cover 6. Then, gas is pumped into the sealing cylinder 12 through the air pump 1 to pressurize it and test the sealing performance of the mechanical seal 7. The gas from the air pump 1 enters the sealing cylinder 12 after passing through the pressure gauge 5.

[0038] like Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, the crossbeam 10 is mounted on the base 14 by the support adjustment bolt 13, and the crossbeam 10 is located directly above the sealing cylinder 12. The support adjustment bolt 13 can adjust the height of the crossbeam 10. After the crossbeam 10 is adjusted to a suitable height, the pressure plate 9 presses down on the mechanical seal 7, and then the subsequent sealing test begins.

[0039] This invention not only solves the problem of difficulty in inspecting single-end mechanical seals using traditional techniques, but also reduces the operation process and inspection time. Using the airtightness testing device for a single-end mechanical seal provided by this invention improves efficiency and reduces risk compared to the traditional method of installing it on the pump body for testing, and the test results meet the requirements.

[0040] Example 2:

[0041] Based on Embodiment 1, in this embodiment, preferably, the pressure plate 9 consists of two pieces, each of which is a long rectangular block with a horizontal through groove at one end, through which the crossbeam 10 passes.

[0042] like Figure 4 As shown in Figure 5, the pressure plate 9 in this utility model is preferably two long rectangular blocks. The two pressure plates 9 are fitted onto the crossbeam 10 through their own through grooves. The relative distance between the two pressure plates 9 can be adjusted according to the different sizes of the mechanical seals 7 to ensure that it is suitable for mechanical seals 7 of various sizes.

[0043] like Figure 5 and 6 As shown, in this utility model, the bolts are divided into two categories: one is the short shaft bolt 11, and the other is the support and adjustment bolt 13.

[0044] In this utility model, there are two support adjustment bolts 13 and two pressure plates 9. The two support adjustment bolts 13, the two pressure plates 9 and the short shaft bolts 11 are all provided on the crossbeam 10. The short shaft bolts 11 are located at the center of the crossbeam 10, and the two support adjustment bolts 13 are located on the outside of the two pressure plates 9.

[0045] In this utility model, the pressure plate 9 can also be ring-shaped or other shapes, as long as the pressure plate 9 is pressed tightly onto the mechanical seal 7.

[0046] Preferably, the sealing cylinder 12 is welded to the base 14 as a whole.

[0047] In this invention, the base 14 and the sealing cylinder 12 are welded together to avoid leakage. The side and planar boreholes of the base 14 are interconnected; the side borehole is sealed with a plug after tapping. A pressure gauge 5 is installed inside the planar borehole. Gas from the air pump 1 passes through the pressure gauge 5 and then enters the sealing cylinder 12. The air pump 1 has an adjustable pressure setting; the required pumping pressure can be selected and determined according to needs, facilitating control.

[0048] Preferably, a filter 3 is provided between the pressure gauge 5 and the air pump 1, and valves 2 are provided at both ends of the filter 3.

[0049] Preferably, a pressure reducing valve 4 is provided between the pressure gauge 5 and the filter 3.

[0050] like Figure 4 As shown, this utility model ensures the cleanliness and pressure accuracy of the compressed air entering the mechanical seal 7 by adding a filter 3 and a pressure reducing valve 4, thus eliminating the damage to the mechanical seal 7 caused by unclean air source and overpressure during the inspection process.

[0051] In this utility model, the pressure reducing valve 4 further ensures that the gas pressure entering the sealed cylinder 12 does not exceed the standard, thus ensuring that the gas pressure entering the sealed cylinder 12 meets the requirements.

[0052] The filter 3 of this utility model has a filtration accuracy of no more than 25μm. This is sufficient to filter out some impurities from the incoming gas.

[0053] Preferably, the upper cover 6 is provided with a sealing groove 15 and a positioning groove 16.

[0054] like Figure 7 As shown, an O-ring is installed in the sealing groove 15 to seal the upper part of the sealing cylinder 12. The positioning groove 16 is a machined groove that mates with the sealing cylinder 12. The sealing groove 15 and the positioning groove 16 serve to position and seal, ensuring that the sealing cylinder 12 will not leak or become misaligned during testing, thus preventing inaccurate testing.

[0055] In this invention, the depth of the sealing groove 15 is the same as the depth of the positioning groove 16, and the positioning groove 16 is located in the middle of the sealing groove 15. The depth of the positioning groove 16 is preferably 1.5 mm, and the distance from the bottom of the positioning groove 16 to the bottom surface of the upper cover 6 is preferably 3 mm.

[0056] In this invention, the sealing cylinder 12 is made of DN150 material with a thickness of 7.11mm. Its pressure does not exceed 0.17MPa.

[0057] Preferably, the maximum outer diameter of the upper cover 6 is greater than the maximum outer diameter of the sealing cylinder 12.

[0058] In this invention, the maximum outer diameter of the upper cover 6 is greater than the maximum outer diameter of the sealing cylinder 12, ensuring that the sealing groove 15 and the positioning groove 16 effectively seal and position the sealing cylinder 12.

[0059] Preferably, four casters are installed under the base 14.

[0060] In this invention, four casters are installed under the base 14 to facilitate movement to the desired location and make it easy to carry and move.

[0061] Preferably, the air pump 1 is a miniature air pump.

[0062] In this invention, the air pump 1 is a miniature air pump, which solves the problem of limited air supply. The miniature air pump used in this invention is a readily available and mature product that can be purchased and used directly. Further details are omitted here.

[0063] Preferably, the upper end of the nylon short shaft 8 is connected to the crossbeam 10 by a short shaft bolt 11.

[0064] In this invention, the nylon short shaft 8 is pressed and sealed to the upper end of the mechanical seal 7 by the short shaft bolt 11, ensuring that the mechanical seal 7 will not run upward during the test.

[0065] This invention solves the problem that, due to the different structural forms of single-end mechanical seals, conventional methods cannot perform external pressure testing on the pump body before installation. This invention has a simple structure, is easy to operate, provides good sealing test results, and improves testing efficiency.

[0066] This utility model can be easily disassembled, assembled, or manufactured. It is small in size, easy to carry and move, and can be conveniently tested and inspected on the construction site.

[0067] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0068] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0069] The examples above are merely illustrative of this utility model and do not constitute a limitation on the scope of protection of this utility model. All designs that are identical or similar to this utility model fall within the scope of protection of this utility model. Device structures and steps not described in detail in this utility model are prior art and will not be further described in this utility model.

Claims

1. A device for testing the airtightness of a single-end mechanical seal, characterized in that: The system includes an air pump (1), a pressure gauge (5), a top cover (6), a mechanical seal (7), a nylon short shaft (8), a pressure plate (9), a crossbeam (10), a sealing cylinder (12), and a base (14). The mechanical seal (7) is located on the top cover (6) of the sealing cylinder (12), and the upper end of the mechanical seal (7) is provided with a nylon short shaft (8). The crossbeam (10) is located on the base (14) by a support adjusting bolt (13), and the crossbeam (10) is located directly above the sealing cylinder (12). The upper end of the pressure plate (9) is located on the crossbeam (10), and the lower end of the pressure plate (9) is located on the upper surface of the mechanical seal (7). The pressure gauge (5) is located on the base (14) and is connected to the air pump (1).

2. The airtightness testing device for a single-end mechanical seal according to claim 1, characterized in that: The pressure plate (9) consists of two pieces, each of which is a long rectangular block. One end of the long rectangular block has a horizontal through groove, and the crossbeam (10) passes through the through groove.

3. The airtightness testing device for a single-end mechanical seal according to claim 1, characterized in that: The sealing cylinder (12) is welded to the base (14) as a whole.

4. The airtightness testing device for a single-end mechanical seal according to claim 1, characterized in that: A filter (3) is provided between the pressure gauge (5) and the air pump (1), and valves (2) are provided at both ends of the filter (3).

5. The airtightness testing device for a single-end mechanical seal according to claim 4, characterized in that: A pressure reducing valve (4) is provided between the pressure gauge (5) and the filter (3).

6. The airtightness testing device for a single-end mechanical seal according to claim 1, characterized in that: The top cover (6) is provided with a sealing groove (15) and a positioning groove (16).

7. The airtightness testing device for a single-end mechanical seal according to claim 1, characterized in that: The maximum outer diameter of the top cover (6) is greater than the maximum outer diameter of the sealing cylinder (12).

8. The airtightness testing device for a single-end mechanical seal according to claim 1, characterized in that: Four casters are installed under the base (14).

9. The airtightness testing device for a single-end mechanical seal according to claim 1, characterized in that: The air pump (1) mentioned above is a miniature air pump.

10. The airtightness testing device for a single-end mechanical seal according to claim 1, characterized in that: The upper end of the nylon short shaft (8) is connected to the crossbeam (10) by a short shaft bolt (11).

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