Turbine blade split baffle ring assembly method and assembly tool

Abstract

The invention aims to provide an assembling method and an assembling tool for a turbine blade split baffle ring. The assembling tool comprises a seat body, a driving block, a baffle block, an elastic element and a driving unit. The seat body is provided with an opening, the driving block is arranged in the opening and provided with a first slope, and the check block is arranged in the opening and provided with a second slope. The elastic element elastically supports the check block in the opening so that the second inclined face can be attached to the first inclined face all the time. The driving unit can drive the driving block to move in the opening in the direction from the upper surface to the lower surface from top to bottom. When the driving unit applies force, the first inclined surface extrudes the second inclined surface, so that the stop block moves towards the elastic element, the elastic element is compressed until the stop part abuts against the inner circumference of the baffle ring, and the driving unit continues to apply force, so that the stop part applies external force to the baffle ring. By means of the assembly tool, local interference between the baffle ring and the sealing ring after assembly can be reduced, and therefore the assembly quality of the low-pressure turbine is improved.

Description

Technical Field

[0001] The invention relates to the field of gas turbine engine assembly, and in particular to an assembly method and an assembly tool for a turbine blade opening retaining ring. Background Art

[0002] The assembly of aircraft engines is an important part of the engine manufacturing process, among which the assembly of turbine blades is particularly important. Figure 1 The figure shows a cross-sectional schematic diagram of the installation location of the existing low-pressure turbine blades. Figure 2 The top view of the existing low-pressure turbine blade installation is shown. The low-pressure turbine blade 91 is axially limited by the open elastic retaining ring 92 to prevent the blade from falling out of the turbine disc groove. The sealing ring 93 forms a stopper with the inner hole of the open elastic retaining ring 92, and the stopper fit clearance is about 0.1-0.2mm, which limits the open retaining ring from the radial direction to prevent the retaining ring 92 from falling out of the installation groove, resulting in failure of the axial limit of the blade.

[0003] Figure 3 The schematic diagram of the open elastic retaining ring is shown. The open elastic retaining ring 92 has an open structure 920 and has a certain elasticity. It can be inserted into the hook groove formed by the blade claw and the turbine disk to press the blade to achieve axial limitation of the blade.

[0004] During the assembly of the low-pressure turbine, the turbine disc, blades, and retaining rings are first assembled into a blade disc assembly, and then the blade disc assemblies, sealing rings, and stator assemblies at various levels are assembled into a low-pressure turbine unit. However, the inventors have found that the existing open elastic retaining rings often interfere with the sealing rings locally after assembly, causing the sealing rings to be unable to be assembled in place, affecting the assembly quality of the low-pressure turbine. Summary of the invention

[0005] The object of the present invention is to provide an assembly tool, which can reduce the local interference between the assembled retaining ring and the sealing ring, thereby improving the assembly quality of the low-pressure turbine.

[0006] An assembly tool for achieving the above-mentioned purpose is used to limit the retaining ring on the turbine disk, and includes:

[0007] The seat body has an opening, and the opening is opened through the upper surface and the lower surface of the seat body;

[0008] A driving block, disposed in the opening, having a first inclined surface;

[0009] A stopper, disposed in the opening, having a second inclined surface;

[0010] an elastic element, elastically supporting the stopper in the opening so that the second inclined surface always fits with the first inclined surface; and

[0011] A driving unit capable of driving the driving block to move from top to bottom in the opening along the upper surface toward the lower surface;

[0012] Wherein, the seat body has a mounting portion, through which it can be detachably mounted on the turbine disk, and the block has a blocking portion protruding from the lower surface. When the driving unit applies force, the first inclined surface squeezes the second inclined surface to make the block move toward the elastic element, and the elastic element is compressed until the blocking portion abuts against the inner circumference of the blocking ring, and the driving unit continues to apply force so that the blocking portion applies external force to the blocking ring.

[0013] In one or more embodiments, the driving block includes a connecting portion and a driving portion, the thickness of the driving portion gradually decreases along the direction from the upper surface to the lower surface to form the first inclined surface, and a through hole is provided on the connecting portion;

[0014] In the assembled state, the connecting portion is located above the upper surface of the seat body, and the stopper elastically supported by the elastic element presses the first inclined surface through the second inclined surface, so that the connecting portion is separated from the upper surface by a distance;

[0015] Among them, the driving unit has a force-applying part and a screw part. The screw part passes through the through hole and is threadedly connected to the seat body. The driving unit can be driven to rotate by applying torque to the force-applying part. When the screw part is screwed into the seat body, the force-applying part squeezes the driving block to drive the driving block to actuate.

[0016] In one or more embodiments, one of the stopper and the side wall of the opening has a guide column, and the other has a guide groove, the guide groove extends along the opening direction of the opening, and the guide column and the guide groove cooperate to limit the movement direction of the stopper in the opening.

[0017] In one or more embodiments, connecting holes are respectively opened in the two side walls of the opening, pin shafts are arranged in the connecting holes, the guide groove is opened inside the block, and in the assembled state, the pin shaft passes through the guide groove, and the pin shaft is the guide column.

[0018] In one or more embodiments, a avoidance hole is opened in the bottom wall of the opening along the opening direction of the opening, and the stopper has a convex column, and the convex column can be movably assembled in the avoidance hole in the assembled state.

[0019] In one or more embodiments, the elastic element is a coil spring, and the coil spring is disposed around the outer periphery of the boss to elastically support the stopper at the avoidance hole.

[0020] In one or more embodiments, the mounting portion is a connecting stud protruding from the lower surface of the seat body, and a mounting hole is provided in the turbine disc. The seat body is mounted on the turbine disc by passing the connecting stud through the mounting hole and connecting it with a nut.

[0021] On the other hand, according to some embodiments of the present application, a method for assembling a turbine blade open retaining ring is also provided, wherein the open retaining ring is assembled using the assembly tool as described above, and the assembly method comprises the following steps:

[0022] Uniformly installing a plurality of the assembly tools on the turbine disk along the inner circumference of the open retaining ring;

[0023] Sequentially operate the driving units of the plurality of assembly tools so that the stoppers of the plurality of stoppers respectively and sequentially abut against the inner circumference of the open stop ring;

[0024] Continue to sequentially operate the driving units of the plurality of assembly tools, so that the plurality of stoppers sequentially squeeze the inner circumference of the open stop ring, and press the open stop ring into the installation groove;

[0025] The plurality of assembly tools are made to exert force on the open retaining ring for a first time or longer, the driving unit is released, and the assembly tools are removed one by one.

[0026] In one or more embodiments, the first time is 12 hours.

[0027] In one or more embodiments, the assembly method further comprises:

[0028] While making the blocking parts of the plurality of blocking blocks respectively and sequentially press against the inner circumference of the open blocking ring, observe whether the inner circumference of the open blocking ring pops out from the installation groove. If so, add the assembly tool at the corresponding position, and make the added assembly tool apply force to the pop-up position so that the open blocking ring is assembled as a whole in the installation groove.

[0029] The beneficial effects of the present invention are:

[0030] Since there is an open space above the turbine disk, the cooperation between the second inclined surface and the first inclined surface allows the movement of the driving block from top to bottom to be converted into the movement of the block along the radial direction of the turbine disk, that is, the direction of the opening, so that the force application method on the retaining ring is easy to operate, and will not be interfered with by other components in the turbine disk, and the assembly of the retaining ring can be easily realized. At the same time, through the setting of the elastic element, when the driving unit is released, the block and the driving block can be quickly reset and separated from the retaining ring, which is convenient for the rapid disassembly of the assembly tool.

[0031] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Moreover, the same reference numerals are used throughout the drawings to represent the same components. In the drawings:

[0033] Figure 1 A cross-sectional schematic diagram of the installation location of the existing low-pressure turbine blades is shown;

[0034] Figure 2 A schematic top view of the installation location of existing low-pressure turbine blades is shown;

[0035] Figure 3 A schematic diagram of an open elastic retaining ring is shown;

[0036] Figure 4 A three-dimensional schematic diagram of an assembly tool according to some embodiments of the present application is shown;

[0037] Figure 5 A half-section schematic diagram of an assembly tool according to some embodiments of the present application is shown;

[0038] Figure 6 An exploded schematic diagram of an assembly tool according to some embodiments of the present application is shown;

[0039] Figure 7 A three-dimensional schematic diagram of an assembly tool according to some embodiments of the present application during assembly is shown;

[0040] Figure 8 A half-section schematic diagram of an assembly tool according to some embodiments of the present application during assembly is shown. DETAILED DESCRIPTION

[0041] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0043] When the applicant used the existing assembly process to assemble the open retaining ring, it was found that since the retaining ring is an open structure and has its own elasticity, it lacks radial positioning after being inserted into the installation groove. It is possible that the retaining ring will partially pop out of the installation groove, causing the inner diameter of the retaining ring to be smaller than the outer diameter of the corresponding stop of the sealing ring, resulting in local interference with the sealing ring, making it impossible to assemble the sealing ring in place, affecting the assembly quality of the low-pressure turbine.

[0044] To solve the aforementioned problems, on the one hand, according to some embodiments of the present application, an assembly tool is provided, such as Figure 4 shows a three-dimensional schematic diagram of an assembly tool according to some embodiments of the present application, Figure 5 A half-section schematic diagram of an assembly tool according to some embodiments of the present application is shown. Figure 6 shows an exploded schematic diagram of an assembly tool according to some embodiments of the present application, Figure 7 shows a three-dimensional schematic diagram of an assembly tool according to some embodiments of the present application during assembly, Figure 8 A half-section schematic diagram of an assembly tool according to some embodiments of the present application during assembly is shown.

[0045] Please refer to Figures 4 to 8 The assembly tool 100 is used to limit the position of the retaining ring 91 on the turbine disk 9 and realize the assembly, and includes a seat body 1, a driving block 2, a stopper 3, an elastic element 4 and a driving unit 5. The seat body 1 has an opening 10, which is opened through the upper surface 11 and the lower surface 12 of the seat body 1. The driving block 2 is arranged in the opening 10 and has a first inclined surface 21. The stopper 3 is arranged in the opening 10 and has a second inclined surface 31. The elastic element 4 elastically supports the stopper 3 in the opening 10, so that the stopper 3 always has a tendency to move toward the driving block 2, so that the second inclined surface 31 always fits with the first inclined surface 21. The driving unit 5 can drive the driving block 2 from top to bottom in the opening 10 along the upper surface 11 toward the lower surface 12, that is, Figure 5 Move in the direction indicated by arrow a.

[0046] The seat body 1 has a mounting portion 13, and the seat body 1 is detachably mounted on the turbine disk 9 through the mounting portion 13. In the assembled state, the stopper 3 has a stopper 30 protruding from the lower surface 12. When the driving unit 5 applies force, the first inclined surface 21 squeezes the second inclined surface 31, so that the stopper 3 moves toward the elastic element 4, squeezing the elastic element 4 to compress it until the stopper 30 abuts against the inner periphery of the stopper ring 91, that is, Figure 8 In the state shown, the driving unit 5 continues to apply force, and the retaining portion 30 can continue to apply external force to the retaining ring 91 until the retaining ring 91 is pressed into the installation groove.

[0047] Since there is an open space above the turbine disk, the cooperation between the second inclined surface 31 and the first inclined surface 21 allows the movement of the driving block 2 from top to bottom to be converted into the movement of the stopper 3 along the radial direction of the turbine disk, that is, the opening direction b of the opening 10, so that the force application method on the stopper ring 91 is easy to operate, and will not be interfered with by other components in the turbine disk, and the assembly of the stopper ring can be easily realized. At the same time, through the setting of the elastic element 4, when the driving unit 5 is released, the stopper 3 and the driving block 2 can be quickly reset and separated from the stopper ring, which is convenient for the rapid disassembly of the assembly tool 100.

[0048] In the description of the embodiments of the present application, the technical terms "first" and "second", such as "first inclined plane", "second inclined plane", etc., are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0049] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0050] In one or more embodiments, the driving block 2 includes a connecting portion 22 and a driving portion 23. The thickness of the driving portion 22 is along the direction from the upper surface 11 to the lower surface 12. Figure 5 The direction indicated by the middle arrow a gradually decreases to form a first inclined surface 21 , and a through hole 220 is provided on the connecting portion 22 .

[0051] In the assembled state, the connecting portion 22 is located above the upper surface 11 of the seat body 1, and the stopper 3 elastically supported by the elastic element 4 presses the first inclined surface 21 through the second inclined surface 31, so that the connecting portion 21 is separated from the upper surface 11 by a distance x;

[0052] The driving unit 5 has a force-applying portion 50 and a screw portion 51. The screw portion 51 passes through the through hole 220 and is threadedly connected to the base 1. The driving unit 5 can be driven to rotate by applying torque to the force-applying portion 50. When the screw portion 51 is screwed into the base 1, the force-applying portion 3 squeezes the driving block 2 to drive the driving block 2 to actuate, thereby further driving the first inclined surface 21 to squeeze the second inclined surface 31. The connection portion 21 is separated from the upper surface 11 by a distance x, which provides space for the driving block 2 to actuate from top to bottom.

[0053] In one or more embodiments, one of the stopper 4 and the side wall of the opening 10 has a guide column, and the other has a guide groove, the guide groove extends along the opening direction b of the opening 10, and the guide column and the guide groove cooperate to limit the movement direction of the stopper in the opening 10. It can be understood that when the assembly tool is installed on the turbine disk 9, the opening direction b of the opening 10 is the radial direction of the turbine disk.

[0054] In a specific embodiment, see Figure 6 , connecting holes 101 are respectively opened in the two side walls of the opening 10, and a pin shaft 102 is arranged in the connecting hole 101. A guide groove 32 is opened inside the stopper 3. In the assembled state, the pin shaft 102 is arranged through the guide groove 32. The pin shaft 102 is a guide column, and together with the guide groove 32, it defines the moving direction of the stopper 3 in the opening 10, thereby ensuring the stability of the movement of the stopper 3.

[0055] In a specific embodiment, see Figure 6 The bottom wall of the opening 10 along the opening direction b is provided with an avoidance hole 103, the stopper has a boss 33, the avoidance hole 103 is slightly larger than the boss 33, and the boss 33 can be movably assembled in the avoidance hole 103 in the assembled state, and the avoidance hole 103 and the boss 33 further guide the movement direction of the stopper 3 to a certain extent, further ensuring the stability of the movement of the stopper 3. At the same time, since the thickness of the retaining ring 91 is very thin, such a setting can limit the movement of the stopper 3 in the vertical direction and prevent the stopper 3 from detaching from the retaining ring 91.

[0056] In a specific embodiment, the elastic element 4 is a coil spring. In the assembled state, the coil spring 4 is disposed around the outer periphery of the boss 33 to elastically support the stopper 3 at the avoidance hole 103 .

[0057] In a specific embodiment, Figure 8 As shown, the mounting portion 13 is a connecting stud protruding from the lower surface of the seat body, and a mounting hole is provided in the turbine disk. The seat body 1 is mounted on the turbine disk 9 by passing the connecting stud through the mounting hole and connecting it with the nut 7, thereby realizing the overall fixation of the assembly tool on the turbine disk.

[0058] On the other hand, according to some embodiments of the present application, a method for assembling a turbine blade split retaining ring is further provided, wherein the split retaining ring is assembled using the assembly tool described in one or more of the previous embodiments, and the assembly method comprises the following steps:

[0059] A plurality of assembly tools 100 are evenly installed on the turbine disk 9 along the inner circumference of the split retaining ring;

[0060] The driving units 5 of the plurality of assembly tools 100 are operated in sequence, so that the stoppers 30 of the plurality of stoppers 3 are respectively pressed against the inner circumference of the open stop ring in sequence;

[0061] Continue to sequentially operate the driving units 5 of the plurality of assembly tools 100, so that the plurality of stoppers 30 sequentially squeeze the inner circumference of the open stop ring, and press the open stop ring into the installation groove;

[0062] A plurality of assembly tools are made to exert force on the open retaining ring for a first time or longer, the driving unit 5 is released, and the assembly tools are removed one by one.

[0063] Since the elastic retaining ring lacks radial limit, extrusion from a single point may cause the retaining ring to move in and out. In this case, multiple retaining ring limit tools can be set in the circumferential direction to limit the retaining ring at multiple points and angles. The limit time lasts for more than the first time, so that the retaining ring yields and deforms, and no longer pops out of the installation slot, without affecting the installation of the sealing ring. In a specific embodiment, the first time is 12 hours, which can achieve continuous force to make the retaining ring 91 yield and deform.

[0064] At the same time, the inventor found that compared with the traditional method of simultaneously applying external force to the inner side of the retaining ring, since the retaining ring is an open retaining ring, the elastic modulus at various locations is not consistent, so the deformation angles are not consistent when subjected to the same force. At the same time, the retaining ring will be locally deformed after the engine test run. In addition, due to manufacturing errors, the materials of the retaining ring are not completely consistent at various angles. The use of multiple points of force at the same time may result in the partial assembly of the retaining ring not being completed. Through the aforementioned assembly method, multiple points of force are applied at dispersed locations, and the magnitude of the force applied to the local part of the retaining ring can be individually controlled through multiple assembly tools, achieving non-uniform yield deformation of multiple points of the retaining ring, so that multiple points of the retaining ring can be maintained in a better assembly position, ensuring the stable assembly of the retaining ring, and reducing the local interference between the assembled retaining ring and the sealing ring, thereby improving the assembly quality of the low-pressure turbine.

[0065] In one or more embodiments, the assembly method further includes: while the stopper portions 30 of the plurality of stoppers 3 are respectively pressed against the inner circumference of the open retaining ring in sequence, observing whether the inner circumference of the open retaining ring pops out from the mounting groove, and if so, adding an assembly tool 100 at the corresponding position, and applying force to the pop-up position by the additional assembly tool 100, so that the open retaining ring is assembled in the mounting groove as a whole. In this way, a limiting tool 100 can be added at a position where the local deformation is large to achieve the yield deformation of the local area, further ensuring the accurate assembly of the retaining ring.

[0066] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like 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 an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. An assembly tool for limiting the position of a retaining ring on a turbine disk, characterized in that: include: The seat body has an opening, and the opening is opened through the upper surface and the lower surface of the seat body; A driving block, disposed in the opening, having a first inclined surface; A stopper, disposed in the opening, having a second inclined surface; an elastic element, elastically supporting the stopper in the opening so that the second inclined surface always fits the first inclined surface; as well as A driving unit capable of driving the driving block to move from top to bottom in the opening along the upper surface toward the lower surface; Wherein, the seat body has a mounting portion, through which it can be detachably mounted on the turbine disk, and the block has a blocking portion protruding from the lower surface. When the driving unit applies force, the first inclined surface squeezes the second inclined surface to make the block move toward the elastic element, and the elastic element is compressed until the blocking portion abuts against the inner circumference of the blocking ring, and the driving unit continues to apply force so that the blocking portion applies external force to the blocking ring.

2. The assembly tool according to claim 1, characterized in that: The driving block comprises a connecting portion and a driving portion, the thickness of the driving portion gradually decreases along the direction from the upper surface to the lower surface to form the first inclined surface, and the connecting portion is provided with a through hole; In the assembled state, the connecting portion is located above the upper surface of the seat body, and the stopper elastically supported by the elastic element presses the first inclined surface through the second inclined surface, so that the connecting portion is separated from the upper surface by a distance; Among them, the driving unit has a force-applying part and a screw part. The screw part passes through the through hole and is threadedly connected to the seat body. The driving unit can be driven to rotate by applying torque to the force-applying part. When the screw part is screwed into the seat body, the force-applying part squeezes the driving block to drive the driving block to actuate.

3. The assembly tool according to claim 2, characterized in that: One of the stopper and the side wall of the opening has a guide column, and the other has a guide groove. The guide groove extends along the opening direction of the opening. The guide column and the guide groove cooperate to limit the movement direction of the stopper in the opening.

4. The assembly tool according to claim 3, characterized in that: The two side walls of the opening are respectively provided with connection holes, the connection holes are provided with pin shafts, the guide groove is provided inside the stopper, and in the assembled state, the pin shaft is provided through the guide groove, and the pin shaft is the guide column.

5. The assembly tool according to claim 3, characterized in that: An avoidance hole is provided in the bottom wall of the opening along the opening direction of the opening, and the stopper has a convex column, which can be movably assembled in the avoidance hole in an assembled state.

6. The assembly tool according to claim 5, characterized in that The elastic element is a coil spring, and the coil spring is circumferentially arranged on the outer periphery of the boss to elastically support the stopper at the avoidance hole.

7. The assembly tool according to claim 1, characterized in that: The mounting portion is a connecting stud protruding from the lower surface of the seat body, and a mounting hole is provided in the turbine disk. The seat body is mounted on the turbine disk by passing the connecting stud through the mounting hole and connecting it with a nut.

8. A method for assembling a turbine blade opening retaining ring, characterized in that: The split retaining ring is assembled using the assembly tool as described in any one of claims 1 to 7, and the assembly method comprises the following steps: Uniformly installing a plurality of the assembly tools on the turbine disk along the inner circumference of the open retaining ring; Sequentially operate the driving units of the plurality of assembly tools so that the stoppers of the plurality of stoppers respectively and sequentially abut against the inner circumference of the open stop ring; Continue to sequentially operate the driving units of the plurality of assembly tools, so that the plurality of stoppers sequentially squeeze the inner circumference of the open stop ring, and press the open stop ring into the installation groove; The plurality of assembly tools are made to exert force on the open retaining ring for a first time or longer, the driving unit is released, and the assembly tools are removed one by one.

9. The turbine blade opening retaining ring assembly method according to claim 8, characterized in that: The first time is 12 hours.

10. The turbine blade opening retaining ring assembly method according to claim 8, characterized in that: The assembly method further comprises: While making the blocking parts of the plurality of blocking blocks respectively and sequentially press against the inner circumference of the open blocking ring, observe whether the inner circumference of the open blocking ring pops out from the installation groove. If so, add the assembly tool at the corresponding position, and make the added assembly tool apply force to the pop-up position so that the open blocking ring is assembled as a whole in the installation groove.

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