Assembly method for mechanical seal of high-speed gearbox

Abstract

The invention discloses an assembly method for a mechanical seal of a high-speed gearbox, which changes an assembly process method of a static sealing ring and a static sealing ring seat, and changes the traditional'assembly after machining 'into'machining after assembly', so that the dimensional precision and the assembly precision of a static sealing ring assembly are improved; a plurality of quality key points such as fitting degree of a rotary sealing ring, end face jumping, end face jumping of a fixed box cover, distribution condition of high and low points of compression springs and the like are controlled and implemented, working pressure selection and matching between friction pairs of dynamic and static rings of a mechanical seal are simulated through a balancing weight, and each compression spring is determined or replaced. It is ensured that all the compression springs are located at the optimal positions in the circumferential direction of the spring seat, accumulative errors caused by different spring stiffness coefficients, spring size heights and spring seat inner holes are completely reduced, and the assembly precision and the assembly quality of the mechanical seal are improved.

Description

Technical Field

[0001] The invention relates to the technical field of mechanical assembly, and in particular to an assembly method for a high-speed gear box mechanical seal. Background Art

[0002] Mechanical seal is a rotary axial end face dynamic sealing device. It often uses the pre-tightening of elastic parts or the pressure of the medium to press the end face of the rotary seal ring against the end face of the stationary seal ring, generating an appropriate specific pressure between the contact friction pairs of the dynamic and static ring ends, and forming a very thin liquid film under the action of lubricating oil to achieve the sealing effect. It has the advantages of less leakage, good sealing effect, long service life, and wide application range (reliable sealing performance under high temperature, high pressure, and high speed conditions). It is widely used in high-speed gearboxes, centrifuges, compressors, reactors and other equipment. In high-speed gearboxes, mechanical seals are mainly composed of rotary seal rings, stationary seal rings, stationary seal ring seats, multiple compression springs, spring seats, dynamic and static ring auxiliary O-rings, and limit retaining rings. In the existing assembly technology, on the one hand, due to the installation errors of the dynamic and static rings, the different stiffness coefficients and height dimensions of multiple compression springs, the differences in the spring installation inner holes (spring seat inner holes) and other factors, the cumulative installation errors are large. On the other hand, the working pressure between the mechanical seals is indirectly calculated by measuring the compression amount of the mechanical seal compression spring before and after installation and the stiffness coefficient value marked on the drawing. Due to the differences in the stiffness coefficients of each compression spring and the existence of measurement errors and cumulative errors, it is difficult to accurately judge the working pressure of the mechanical seal after installation. In addition, the conventional assembly process route is not only complicated, but also has large measurement errors and cumulative errors, which greatly reduces the assembly accuracy of the mechanical seal and is prone to the risk and hidden danger of oil leakage after assembly. Summary of the invention

[0003] In view of the above-mentioned deficiencies in the prior art, the technical problem to be solved by the present invention is: how to provide an assembly method for a high-speed gearbox mechanical seal that can accurately control assembly errors at each stage and improve the assembly accuracy and assembly quality of the mechanical seal.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions: A method for assembling a high-speed gearbox mechanical seal comprises the following steps: (1) Obtain a rotating sealing ring, a stationary sealing ring, a stationary sealing ring seat, a compression spring, a limit retaining ring, a spring seat, an adjustment gasket, a distance ring, a rotating shaft and a fixed box cover, wherein the rotating shaft passes through the fixed box cover; (2) Install the stationary sealing ring in the inner hole at one end of the stationary sealing ring seat by interference fit, process the outer end surface of the stationary sealing ring to meet the shape and position tolerance and size requirements, install an O-ring on the outer circle of the other end of the stationary sealing ring seat to obtain a stationary sealing ring assembly, and test whether the sealing performance of the stationary sealing ring assembly is qualified; (3) Install the distance ring, rotating sealing ring and stationary sealing ring assembly on the rotating shaft, check whether the contact spot K1 between the rotating sealing ring and the distance ring meets the requirements, and check whether the contact spot K2 between the rotating sealing ring and the stationary sealing ring meets the requirements; (4) Axially limit the rotating seal ring, check the runout value of the contact surface K2 on the rotating seal ring with the outer mounting surface of the fixed cover as the reference, and then check the runout value of the outer mounting surface of the fixed cover with the rotating shaft as the reference; (5) Install N compression springs in spring holes evenly spaced around the center line of the spring seat on the spring seat, and test the compression of each compression spring according to the design pressure required by the mechanical seal to ensure that it is qualified; (6) Install the rotating sealing ring, stationary sealing ring, stationary sealing ring seat, compression spring, spring seat and distance ring on the rotating shaft as required; (7) Apply a force along the axial direction of the rotating shaft to the spring seat. This force is the same as the design pressure required by the mechanical seal and satisfies the corresponding compression amount of each compression spring. Measure the distance L between the mounting surface of the spring seat and the outer mounting surface of the fixed box cover in this state. Select an adjustment gasket of corresponding thickness according to the distance L to meet the requirement. Install the adjustment gasket between the mounting surface of the spring seat and the outer mounting surface of the fixed box cover. Finally, use the fixing bolts to fix the spring seat to the fixed box cover.

[0005] As an optimization, in step (2), a stationary sealing ring water pressure sealing performance test device is obtained, comprising an upper top plate and a lower top plate which are arranged in parallel and opposite to each other, a bottom hole is recessed on the upper surface of the lower top plate, one end of the stationary sealing ring seat is inserted into the bottom hole, so that the stationary sealing ring seat is sealed between the O-ring and the inner wall of the bottom hole, the upper top plate is pressed onto the stationary sealing ring located at the other end of the stationary sealing ring seat, a sealing gasket is arranged between the stationary sealing ring and the upper pressing plate, the upper top plate is pressed onto the stationary sealing ring by tightening bolts arranged around the stationary sealing ring seat, a water inlet hole is opened on the upper top plate at a position corresponding to the inner hole of the stationary sealing ring seat, water is injected into the stationary sealing ring seat through the water inlet hole to maintain pressure, and the fitting point P between the stationary sealing ring and the stationary sealing ring seat, and the fitting point Q between the O-ring and the stationary sealing ring seat and the bottom hole are observed to see if there is any leakage, and whether the water pressure drops. Only after the test is qualified can the next step be entered.

[0006] As an optimization, in step (3), after colorant is evenly applied on the contact surface K1 of the rotating sealing ring, the distance ring and the rotating sealing ring are sequentially installed on the rotating shaft, so that the distance ring and the rotating sealing ring are in contact with each other and maintain axial pressure in relative directions. After rotating the rotating sealing ring for one circle, check that the contact spot of the contact surface K1 between the rotating sealing ring and the distance ring is ≥80%, and there is no gap and the contact spot is uniform in the entire circumference; after colorant is evenly applied on the contact surface K2 of the stationary sealing ring, the stationary sealing ring assembly is installed on the rotating shaft, so that the stationary sealing ring is in contact with the rotating sealing ring and maintain axial pressure in relative directions. After rotating the stationary sealing ring assembly for one circle, check that the contact spot of the contact surface K2 between the rotating sealing ring and the stationary sealing ring is ≥80%, and there is no gap and the contact spot is uniform in the entire circumference.

[0007] As an optimization, when installing the compression springs in step (5), first select and arrange the compression springs, place the spring seat on a horizontal platform, make the spring hole face upward, put all the compression springs into the spring holes respectively, measure the spring end face distance from the upper end face of each compression spring in a free state to the upper surface of the horizontal platform, select the center of the spring hole where the compression spring corresponding to the maximum value of the spring end face distance is located as the first reference position, retain the compression spring at this position, and rearrange the remaining compression springs, taking the center of the circle where the centers of all the spring holes are located as the symmetry point, taking the position symmetrical to the first reference position as the second reference position, taking the line between the first reference position and the second reference position as the reference symmetry line AA, and arranging the compression springs at the second reference position. When the compression springs When the number N is an even number, the number of the spring holes located at the second reference position is one and the center thereof is located on the reference symmetry line AA. When the number N of the compression springs is an odd number, the number of the spring holes located at the second reference position is two and the centers thereof are symmetrically arranged about the reference symmetry line AA. The compression springs located at the second reference position are arranged to meet the requirement that the difference in spring end face distance from the compression springs located at the first reference position is not greater than 0.1 mm. The compression springs at the remaining positions are then arranged step by step from the first reference position and the second reference position along their relative directions. Each stage includes two compression springs symmetrically arranged about the reference symmetry line AA, to meet the requirement that the difference in spring end face distance between the two compression springs in each stage is not greater than 0.1 mm, and the difference in spring end face distance between the two compression springs located at the same side and at two adjacent stages is not greater than 0.5 mm. Obtain a counterweight block, the upper plane and the lower plane of the counterweight block are parallel planes, ensure that the center of gravity of the counterweight block is located on its center line, and the mass of the counterweight block is calculated according to the design pressure required by the mechanical seal, and place the counterweight block above the spring seat so that the center line of the counterweight block coincides with the center line of the spring seat, and support the lower plane of the counterweight block by all the compression springs. After the counterweight block is in a stable static state, use the first reference position and the second reference position as measurement starting points, respectively measure the distance value difference between the upper plane of the counterweight block and the upper end face of the spring seat at this location, and the difference is no more than 0.1mm, and evenly measure the distance value difference between the upper plane of the counterweight block and the upper end face of the spring seat at multiple locations symmetrically located at symmetrical points, and the difference is no more than 0.1mm. After meeting the requirements, mark the assembly position of each compression spring for subsequent assembly.

[0008] As an optimization, during the installation process of step (6), the spring seat is placed vertically with the spring hole facing upward, and each compression spring is respectively installed in the spring hole of the spring seat; the stationary sealing ring assembly is installed in the spring seat and abuts against each compression spring, the stationary sealing ring seat and the spring seat are sealed by the O-ring, and the limit retaining ring is installed in the spring seat to ensure that the stationary sealing ring assembly can be axially limited; a force is applied to the stationary sealing ring assembly in the axial direction downward, and after testing that the axial movement process of the stationary sealing ring assembly meets the requirements, it is installed on the rotating shaft.

[0009] As an optimization, in step (7), an installation distance measurement auxiliary device is obtained, including a hydraulic drive device, a fixing tool and a piston seat, the piston seat is provided with a mounting through hole that can slide with the rotating shaft, a side surface of the piston seat along the center line direction of the mounting through hole is provided with a plurality of piston holes evenly spaced around the center line direction of the mounting through hole, the center line direction of the piston hole is parallel to the center line direction of the mounting through hole, each piston hole is provided with a piston column slidingly sealingly matched along the center line direction of the piston hole, and the bottom of the piston hole is provided with an oil inlet channel connected to the outside of the piston seat, when in use, the piston seat is sleeved on the rotating shaft through the mounting through hole and is located behind the spring seat, and each piston column is respectively abutted against the spring seat, the fixing tool is located behind the piston seat and abuts against the piston seat to limit the piston seat, and the fixing tool is fixed to the rotating shaft, the oil supply end of the hydraulic drive device is connected to each oil inlet channel through the oil supply path, according to the design pressure required by the mechanical seal, the output pressure corresponding to the hydraulic drive device is calculated, and the hydraulic drive piston column pushes the spring seat to compress the compression spring. That is, lubricating oil medium is filled into the piston hole, and the design pressure of the mechanical seal is directly converted into the pressure P (unit Pa) of the hydraulic oil in the hydraulic drive device according to the effective area S of the piston column and the working pressure of the mechanical seal (P=F / S). The reading of the pressure gauge directly and truly reflects the working pressure or design pressure of the mechanical seal, completely avoiding the measurement error and installation cumulative error caused by the difference in the stiffness coefficients of each compression spring, multiple measurements of compression before and after installation, improper installation, human factors and errors of different assembly platforms.

[0010] Compared with the prior art, the present invention firstly changes the assembly process method of the stationary sealing ring and the stationary sealing ring seat from the traditional "assembly after processing" to "processing after assembly", thereby improving the dimensional accuracy and assembly accuracy of the stationary sealing ring assembly. Furthermore, the present invention controls and implements multiple key quality points such as the fit of the rotating sealing ring, the end face runout and the end face runout of the fixed box cover, and the distribution of the high and low points of the compression spring. The counterweight block is used to simulate the working pressure between the friction pairs of the dynamic and static rings of the mechanical seal to select, determine or replace each compression spring, thereby ensuring that each compression spring is in the optimal position in the circumferential direction of the spring seat, completely reducing the cumulative error caused by the different spring stiffness coefficients, spring size heights and spring seat inner holes, thereby improving the assembly accuracy and assembly quality of the mechanical seal. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is a flow chart of the present invention; Figure 2 It is a schematic diagram of the installation structure of the mechanical seal in the present invention; Figure 3 It is a structural diagram of the water pressure sealing performance test structure of the stationary sealing ring in the present invention; Figure 4 It is a sequential diagram of the arrangement of the compression springs in the present invention; Figure 5 This is a schematic diagram of the compression test structure of the compression spring in the present invention; Figure 6 It is a structural schematic diagram of the installation distance measurement auxiliary device in the present invention in use state. DETAILED DESCRIPTION

[0012] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention.

[0013] It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. In the description of the present invention, it should be noted that the orientation or position relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the invention product is usually placed when used, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying 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 of the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance. In addition, the terms "horizontal", "vertical", etc. do not mean that the components are absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted. In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0014] like Figures 1 to 6 As shown, the assembly method of the high-speed gearbox mechanical seal in this specific embodiment includes the following steps: (1) Obtain a rotating sealing ring 1, a stationary sealing ring 2, a stationary sealing ring seat 3, a compression spring 4, a limit ring 5, a spring seat 6, an adjustment gasket 7, a distance ring 8, a rotating shaft 9 and a fixed box cover 10, wherein the rotating shaft 9 passes through the fixed box cover 10; (2) The stationary sealing ring 2 is interference-fitted into the inner hole at one end of the stationary sealing ring seat 3, and the outer end surface of the stationary sealing ring 2 is processed to meet the shape and position tolerance and size requirements. An O-ring 11 is installed on the outer circle of the other end of the stationary sealing ring seat 3 to obtain a stationary sealing ring assembly, and the sealing performance of the stationary sealing ring assembly is tested to be qualified; here, the sealing effect of the O-ring 11 and the sealing performance between the stationary sealing ring 2 and the stationary sealing ring seat 3 need to be tested, and the next step is entered after the test is qualified; (3) Install the distance ring 8, the rotating sealing ring 1 and the stationary sealing ring assembly on the rotating shaft 9, check whether the contact spot K1 on the contact surface between the rotating sealing ring 1 and the distance ring 8 meets the requirements, and check whether the contact spot K2 on the contact surface between the rotating sealing ring 1 and the stationary sealing ring 2 meets the requirements; (4) Axially limit the rotating seal ring 1, and check the runout value of the contact surface K2 on the rotating seal ring 1 with the outer mounting surface of the fixed cover 10 as the reference to see if it is qualified, and then check the runout value of the outer mounting surface of the fixed cover 10 with the rotating shaft 9 as the reference to see if it is qualified; (5) Install N compression springs 4 in spring holes evenly spaced around the center line of the spring seat 6 on the spring seat 6, and test the compression amount of each compression spring 4 according to the design pressure required by the mechanical seal to ensure that it is qualified; (6) Install the rotating sealing ring, stationary sealing ring, stationary sealing ring seat, compression spring, spring seat and distance ring on the rotating shaft as required; (7) Apply a force along the axial direction of the rotating shaft 9 to the spring seat 6. The force is the same as the design pressure required by the mechanical seal and satisfies the corresponding compression amount of each compression spring 4. Measure the distance L between the mounting surface of the spring seat 6 and the outer mounting surface of the fixed box cover 10 in this state. Select an adjustment gasket 7 with a corresponding thickness according to the distance L to meet the requirement. Install the adjustment gasket 7 at the position between the mounting surface of the spring seat 6 and the outer mounting surface of the fixed box cover 10. Finally, use the fixing bolts to fix the spring seat 6 to the fixed box cover 10.

[0015] In step (2), a stationary sealing ring water pressure sealing performance test device is obtained, comprising an upper top plate 13 and a lower top plate 14 arranged in parallel and opposite to each other, a bottom hole is concavely provided on the upper surface of the lower top plate 14, one end of the stationary sealing ring seat 3 is installed in the bottom hole, so that the stationary sealing ring seat 4 is sealed between the O-ring I11 and the inner wall of the bottom hole, the upper top plate 13 is pressed on the stationary sealing ring 2 located at the other end of the stationary sealing ring seat 3, a sealing gasket 15 is arranged between the stationary sealing ring 2 and the upper pressing plate 13, and the stationary sealing ring 2 is sealed by the O-ring I11. The tensioning bolts 16 arranged around the stationary sealing ring seat 3 press the upper plate 13 against the stationary sealing ring 2. The upper plate 13 is provided with a water inlet hole corresponding to the position of the inner hole of the stationary sealing ring seat 3. Water is injected into the stationary sealing ring seat 3 through the water inlet hole to maintain the pressure. The fitting point P between the stationary sealing ring 2 and the stationary sealing ring seat 3, and the fitting point Q between the O-ring Ⅰ11 and the stationary sealing ring seat 3 and the bottom hole are observed to see if there is any leakage, and whether the water pressure drops. The next step can be entered only after the test is qualified. First, install the stationary sealing ring seat 3 into the bottom hole, and then put the stationary sealing ring seat 3 and the lower top plate 14 into the heating box for overall heating. The heating temperature is calculated based on the maximum interference between the stationary sealing ring 2 and the stationary sealing ring seat 3 and the minimum clearance required for baking. The heating time and the insulation time are estimated based on the thickness of the stationary sealing ring seat 3. Generally, for every 10mm of thickness, the heating time is 10-15min, and for every 40mm of thickness, the insulation time is 10-15min. After the heating is completed, quickly install the stationary sealing ring 2 into the inner hole of the stationary sealing ring seat 3, make it close to the inner hole shoulder, and then quickly fasten it to the lower top plate 14 with the upper top plate 13 and the tension bolts 16 to prevent the stationary sealing ring seat 3 from serious shrinkage during the cooling process and reduce the assembly error. Remove it after cooling to room temperature. After aligning the outer circle of the stationary sealing ring 2 and its end face runout ≤0.01mm, process the end face of the stationary sealing ring 2 according to the assembly diagram of the stationary sealing ring assembly, and the end face is not allowed to have quality defects such as cracks, inclusions, and damage. During the water injection and pressure maintenance process, the water pressure must reach 0.4±0.05MPa and be maintained for 60 minutes continuously. The next step can only be carried out after verification.

[0016] In step (3), after colorant is evenly applied on the contact surface K1 of the rotating seal ring 1, the distance ring 8 and the rotating seal ring 1 are sequentially installed on the rotating shaft 9, so that the distance ring 8 and the rotating seal ring 1 are in contact with each other and maintain axial pressure in relative directions. After rotating the rotating seal ring 1 for one circle, check that the contact spot of the contact surface K1 between the rotating seal ring 1 and the distance ring 8 is ≥80%, and there is no gap and the contact spot is uniform in the entire circumference; after colorant is evenly applied on the contact surface K2 of the stationary seal ring 2, the stationary seal ring assembly is installed on the rotating shaft 9, so that the stationary seal ring 2 is in contact with the rotating seal ring 1 and maintain axial pressure in relative directions. After rotating the stationary seal ring assembly for one circle, check that the contact spot of the contact surface K2 between the rotating seal ring 1 and the stationary seal ring 2 is ≥80%, and there is no gap and the contact spot is uniform in the entire circumference.

[0017] When installing the compression spring 4 in step (5), first select and arrange the compression spring 4, place the spring seat 6 on the horizontal platform 17, make the spring hole face upward, put all the compression springs 4 into the spring holes respectively, measure the spring end face distance from the upper end face of each compression spring 4 in the free state to the upper surface of the horizontal platform 17, select the center of the spring hole where the compression spring 4 corresponding to the maximum value of the spring end face distance is located as the first reference position, retain the compression spring 4 at this position, and rearrange the remaining compression springs 4, take the center of the circle where the center of all the spring holes is located as the symmetry point, take the position symmetrical to the first reference position as the second reference position, and use the first reference position as the reference point. The connecting line between the second reference positions is used as the reference symmetry line AA, and the compression springs 4 at the second reference positions are arranged. When the number N of the compression springs 4 is an even number, the number of the spring holes at the second reference position is one and the center thereof is located on the reference symmetry line AA. When the number N of the compression springs 4 is an odd number, the number of the spring holes at the second reference position is two and the centers thereof are symmetrically arranged about the reference symmetry line AA. The compression springs 4 at the second reference position are arranged so as to ensure that the difference in the distance from the spring end surface of the compression spring 4 at the first reference position is not greater than 0.1 mm. The compression springs 4 at the remaining positions are arranged step by step from the first reference position and the second reference position along their relative directions. Figure 4 The arrow direction in is the arrangement direction, and each stage includes two compression springs 4 arranged symmetrically with respect to the reference symmetry line AA, satisfying that the difference in spring end face distance between the two compression springs 4 in each stage is not greater than 0.1 mm, and the difference in spring end face distance between the two compression springs 4 in two adjacent stages and located on the same side is not greater than 0.5 mm; Obtain a counterweight 18, the upper plane and the lower plane of the counterweight 18 are parallel planes, ensure that the center of gravity of the counterweight 18 is located on its center line, and the mass of the counterweight 18 is calculated according to the design pressure required by the mechanical seal, that is, m=F / g (where F is the design pressure, unit N, m is the mass of the counterweight, unit kg, and g is the gravity acceleration, unit N / kg). Place the counterweight 18 above the spring seat 6 so that the center line of the counterweight 18 coincides with the center line of the spring seat 6, and press the counterweight 18 against all the compression springs 4. The lower plane of 18 is supported. After the counterweight 18 is in a stable and stationary state, the first reference position and the second reference position are used as the measurement starting points. The difference in the distance between the upper plane of the counterweight 18 and the upper end surface of the spring seat 6 at that location is measured, and the difference is not greater than 0.1 mm. The distance between the upper plane of the counterweight 18 and the upper end surface of the spring seat 6 at multiple locations symmetrically located at symmetrical points is evenly measured, and the difference is not greater than 0.1 mm. After the requirements are met, the assembly position of each compression spring 4 is marked to facilitate subsequent assembly.

[0018] During the installation process of step (6), the surfaces of the stationary sealing ring seat 3, the compression spring 4, the limit retaining ring 5 and the spring seat 6 are cleaned, the spring seat 6 is placed vertically with the spring hole facing upward, and each compression spring 4 is respectively installed in the spring hole of the spring seat 6; after applying appropriate lubricating oil on the O-ring Ⅰ11, the stationary sealing ring assembly is installed in the spring seat 6 and abutted against each compression spring 4, the stationary sealing ring seat 3 and the spring seat 6 are sealed by the O-ring Ⅰ11, and the The limit retaining ring 5 ensures that the stationary sealing ring assembly can be axially limited; a force is applied to the stationary sealing ring assembly along the axial direction of the stationary sealing ring assembly to check whether the stationary sealing ring assembly can move smoothly and flexibly under the action of the axial force, and whether there is any sticking or other phenomena. The test number is ≥ 2 times. After the axial movement process of the stationary sealing ring assembly meets the requirements, it is installed on the rotating shaft 9. In addition, the distance ring 8 and the rotating sealing ring 1 are installed on the rotating shaft 9, and the rotating sealing ring 1 and the distance ring 8 are sealed by an O-ring II 12.

[0019] In step (7), an installation distance measurement auxiliary device is obtained, including a hydraulic drive device, a fixing tool 19 and a piston seat 20. The piston seat 20 is provided with an installation through hole that can slide with the rotating shaft 9. The side surface of the piston seat 20 along the center line direction of the installation through hole is provided with a plurality of piston holes evenly spaced around the center line direction of the installation through hole. The center line direction of the piston hole is parallel to the center line direction of the installation through hole. A piston column 21 is provided in each piston hole along the center line direction of the piston hole. An oil inlet channel connected to the outside of the piston seat 20 is provided at the bottom of the piston hole. When in use, the piston seat 20 is installed through a perforated sleeve on the rotating shaft 9 and is located at a position behind the spring seat 6, and each piston column 21 is respectively abutted against the spring seat 6, the fixing tool 19 is placed behind the piston seat 20 and abuts against the piston seat 20 to limit the piston seat 20, and the fixing tool 19 is fixed to the rotating shaft 9, the oil supply end of the hydraulic drive device is respectively connected to each oil inlet channel through the oil supply path, and the output pressure corresponding to the hydraulic drive device is calculated according to the design pressure required by the mechanical seal, and the effective area S of the action is calculated by the inner and outer diameters of the piston column 21, that is, S=π×(D 外 2 -D 内 2 ) / 4 (unit: m 2 ), and then directly convert the design pressure required by the mechanical seal into the hydraulic oil pressure P (unit Pa) in the hydraulic drive device according to P=F / S, and push the spring seat 6 to compress the compression spring 4 through the hydraulic drive piston column 21.

[0020] In step (7), when measuring the distance L, even-numbered positions are measured at uniform intervals around the center line of the rotation axis 9 to ensure that the difference in the distance L measurement values ​​at the symmetrical positions is no more than 0.1 mm. The average value is calculated based on the distance L measurement values ​​at different positions and used as the thickness value of the adjustment gasket 7.

[0021] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described with reference to the preferred embodiments of the present invention, it should be understood by those skilled in the art that various changes may be made in form and details without departing from the spirit and scope of the present invention as defined in the appended claims.

Claims

1. A method for assembling a high-speed gearbox mechanical seal, characterized in that: The following steps are involved: (1) Obtain a rotating sealing ring, a stationary sealing ring, a stationary sealing ring seat, a compression spring, a limit retaining ring, a spring seat, an adjustment gasket, a distance ring, a rotating shaft and a fixed box cover, wherein the rotating shaft passes through the fixed box cover; (2) Install the stationary sealing ring in the inner hole at one end of the stationary sealing ring seat by interference fit, process the outer end surface of the stationary sealing ring to meet the shape and position tolerance and size requirements, install an O-ring on the outer circle of the other end of the stationary sealing ring seat to obtain a stationary sealing ring assembly, and test whether the sealing performance of the stationary sealing ring assembly is qualified; (3) Install the distance ring, rotating sealing ring and stationary sealing ring assembly on the rotating shaft, check whether the contact spot K1 between the rotating sealing ring and the distance ring meets the requirements, and check whether the contact spot K2 between the rotating sealing ring and the stationary sealing ring meets the requirements; (4) Axially limit the rotating seal ring, check the runout value of the contact surface K2 on the rotating seal ring with the outer mounting surface of the fixed cover as the reference, and then check the runout value of the outer mounting surface of the fixed cover with the rotating shaft as the reference; (5) Install N compression springs in spring holes evenly spaced around the center line of the spring seat on the spring seat, and test the compression of each compression spring according to the design pressure required by the mechanical seal to ensure that it is qualified; (6) Install the rotating sealing ring, stationary sealing ring, stationary sealing ring seat, compression spring, spring seat and distance ring on the rotating shaft as required; (7) Apply a force along the axial direction of the rotating shaft to the spring seat. This force is the same as the design pressure required by the mechanical seal and satisfies the corresponding compression amount of each compression spring. Measure the distance L between the mounting surface of the spring seat and the outer mounting surface of the fixed box cover in this state. Select an adjustment gasket of corresponding thickness according to the distance L to meet the requirement. Install the adjustment gasket between the mounting surface of the spring seat and the outer mounting surface of the fixed box cover. Finally, use the fixing bolts to fix the spring seat to the fixed box cover.

2. The assembly method of the high-speed gearbox mechanical seal according to claim 1, characterized in that: In step (2), a stationary sealing ring water pressure sealing performance test device is obtained, comprising an upper top plate and a lower top plate arranged in parallel and opposite to each other, a bottom hole is recessed on the upper surface of the lower top plate, one end of the stationary sealing ring seat is inserted into the bottom hole, the stationary sealing ring seat is sealed between the O-ring and the inner wall of the bottom hole, the upper top plate is pressed onto the stationary sealing ring located at the other end of the stationary sealing ring seat, a sealing gasket is arranged between the stationary sealing ring and the upper pressing plate, the upper top plate is pressed onto the stationary sealing ring by tightening bolts arranged around the stationary sealing ring seat, a water inlet hole is opened on the upper top plate at a position corresponding to the inner hole of the stationary sealing ring seat, water is injected into the stationary sealing ring seat through the water inlet hole to maintain pressure, and the fitting point P between the stationary sealing ring and the stationary sealing ring seat, and the fitting point Q between the O-ring and the stationary sealing ring seat and the bottom hole are observed to see if there is any leakage, and whether the water pressure drops. The next step can be entered only after the test is qualified.

3. The assembly method of the high-speed gearbox mechanical seal according to claim 1, characterized in that: In step (3), after colorant is evenly applied on the contact surface K1 of the rotating sealing ring, the distance ring and the rotating sealing ring are sequentially installed on the rotating shaft, so that the distance ring and the rotating sealing ring are in contact with each other and maintain axial pressure in relative directions. After rotating the rotating sealing ring for one circle, check that the contact spot of the contact surface K1 between the rotating sealing ring and the distance ring is ≥80%, and there is no gap and the contact spot is uniform in the entire circumference; after colorant is evenly applied on the contact surface K2 of the stationary sealing ring, the stationary sealing ring assembly is installed on the rotating shaft, so that the stationary sealing ring is in contact with the rotating sealing ring and maintain axial pressure in relative directions. After rotating the stationary sealing ring assembly for one circle, check that the contact spot of the contact surface K2 between the rotating sealing ring and the stationary sealing ring is ≥80%, and there is no gap and the contact spot is uniform in the entire circumference.

4. The assembly method of the high-speed gearbox mechanical seal according to claim 1, characterized in that: When installing the compression springs in step (5), first select and arrange the compression springs, place the spring seat on a horizontal platform with the spring hole facing upward, put all the compression springs into the spring holes respectively, measure the spring end face distance from the upper end face of each compression spring in a free state to the upper surface of the horizontal platform, select the center of the spring hole where the compression spring corresponding to the maximum value of the spring end face distance is located as the first reference position, retain the compression spring at this position, and rearrange the remaining compression springs, using the center of the circle where the centers of all the spring holes are located as the symmetry point, the position symmetrical to the first reference position as the second reference position, and the line between the first reference position and the second reference position as the reference symmetry line AA, arrange the compression springs at the second reference position, and when the number of the compression springs is When N is an even number, the number of the spring holes located at the second reference position is one and the center thereof is located on the reference symmetry line AA. When the number of the compression springs N is an odd number, the number of the spring holes located at the second reference position is two and the centers thereof are symmetrically arranged about the reference symmetry line AA. The compression spring located at the second reference position is arranged to meet the requirement that the difference in spring end face distance from the compression spring located at the first reference position is not greater than 0.1 mm. The compression springs at the remaining positions are then arranged step by step from the first reference position and the second reference position along their relative directions. Each stage includes two compression springs symmetrically arranged about the reference symmetry line AA, meeting the requirement that the difference in spring end face distance between the two compression springs in each stage is not greater than 0.1 mm, and the difference in spring end face distance between the two compression springs located at the same side and at two adjacent stages is not greater than 0.5 mm. Obtain a counterweight block, the upper plane and the lower plane of the counterweight block are parallel planes, ensure that the center of gravity of the counterweight block is located on its center line, and the mass of the counterweight block is calculated according to the design pressure required by the mechanical seal, and place the counterweight block above the spring seat so that the center line of the counterweight block coincides with the center line of the spring seat, and support the lower plane of the counterweight block by all the compression springs. After the counterweight block is in a stable static state, use the first reference position and the second reference position as measurement starting points, respectively measure the distance value difference between the upper plane of the counterweight block and the upper end face of the spring seat at this location, and the difference is no more than 0.1mm, and evenly measure the distance value difference between the upper plane of the counterweight block and the upper end face of the spring seat at multiple locations symmetrically located at symmetrical points, and the difference is no more than 0.1mm. After meeting the requirements, mark the assembly position of each compression spring for subsequent assembly.

5. The assembly method of the high-speed gearbox mechanical seal according to claim 1, characterized in that: During the installation process of step (6), the spring seat is placed vertically with the spring hole facing upward, and each compression spring is installed in the spring hole of the spring seat respectively; the stationary sealing ring assembly is installed in the spring seat and abuts against each compression spring, the stationary sealing ring seat and the spring seat are sealed by the O-ring, and the limit retaining ring is installed in the spring seat to ensure that the stationary sealing ring assembly can be axially limited; a force is applied to the stationary sealing ring assembly in the axial direction downward, and after testing that the axial movement process of the stationary sealing ring assembly meets the requirements, it is installed on the rotating shaft.

6. The method for assembling a high-speed gearbox mechanical seal according to claim 1, characterized in that: In step (7), an installation distance measurement auxiliary device is obtained, including a hydraulic drive device, a fixing tool and a piston seat. The piston seat is provided with a mounting through hole that can slide with the rotating shaft. A plurality of piston holes are recessed on the side surface of the piston seat along the center line direction of the mounting through hole and are evenly spaced around the center line direction of the mounting through hole. The center line direction of the piston hole is parallel to the center line direction of the mounting through hole. A piston column is provided in each piston hole along the center line direction of the piston hole for sliding sealing. An oil inlet channel connected to the outside of the piston seat is provided at the bottom of the piston hole. When in use, the piston seat is sleeved on the rotating shaft through the mounting through hole and is located behind the spring seat, and each piston column is respectively abutted against the spring seat. The fixing tool is located behind the piston seat and abuts against the piston seat to limit the piston seat, and the fixing tool is fixed to the rotating shaft. The oil supply end of the hydraulic drive device is connected to each oil inlet channel through an oil supply path. According to the design pressure required by the mechanical seal, the output pressure corresponding to the hydraulic drive device is calculated, and the spring seat is pushed by the hydraulic drive piston column to compress the compression spring.

7. The assembly method of the high-speed gearbox mechanical seal according to claim 1, characterized in that: In step (7), when measuring the distance L, even-numbered positions are measured at uniform intervals around the center line of the rotation axis to ensure that the difference in the distance L measurement values ​​at the symmetrical positions is no more than 0.1 mm. The average value is calculated based on the distance L measurement values ​​at different positions and used as the thickness value of the adjustment gasket.

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