Vertical shaft heading machine, sealing system of vertical shaft heading machine and combined sealing device with active pressure compensation

Abstract

The invention relates to the technical field of vertical shaft heading machines, in particular to a vertical shaft heading machine, a sealing system of the vertical shaft heading machine and an active pressure compensation combined sealing device. The combined sealing device comprises a main sealing body and a sealing pressing ring. The sealing pressing ring and the first side wall jointly form a containing space of the pressure adjusting part so that the pressure adjusting part can abut against the first side wall in the containing space, and the sealing part penetrates through the containing space to abut against the second side wall. The pressure adjusting part is further provided with a pressure adjusting cavity, and the gap distance or contact stress between the sealing part and the second side wall can be changed by changing the pressure in the pressure adjusting cavity. The vertical shaft heading machine uses the combined sealing device to seal a main driving system, the compensation pressure of the pressure adjusting cavity can be changed according to the environment pressure, the sealing effect is improved, it is guaranteed that core components of the vertical shaft heading machine are prevented from being impacted by pressure, and the service life of the combined sealing device can be prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of shaft boring machines, and in particular to a shaft boring machine and a sealing system thereof, and a combined sealing device for active pressure compensation. Background Art

[0002] The shaft boring machine is a device specially used for shaft construction. It is widely used in mining, marine engineering, water conservancy, new energy and other construction fields, providing a boring tool for deep earth engineering, underground parking lots, underground space development, etc.

[0003] During the construction process, the shaft boring machine is easily affected by external environmental pressure and external substances. Therefore, the main drive sealing device of the shaft boring machine becomes an important part of the main drive system of the shaft boring machine. It is used to ensure the sealing performance of the main bearing, a key component of the main drive system, resist the external high confining mud pressure, and prevent external mud or internal sealing medium from entering the main bearing cavity.

[0004] In the construction of shallow shafts, the existing main drive sealing devices mostly adopt a single-lip-multi-lip combined sealing structure, which can meet the better sealing requirements. However, when the shaft depth increases, the threat of external pressure increases accordingly. The traditional sealing form needs to increase the number of sealing channels on the existing basis to meet the additional sealing requirements, and the sealing channel space is limited. In addition, the existing contact sealing form relies on the self-tightening sealing principle under high pressure and relies on the large elastic-plastic deformation of the material to produce a sealing effect. Excessive deformation under high pressure means that the sealing components need to be replaced more frequently during use, which will have an adverse effect on the construction progress of the tunnel boring machine. Therefore, the existing main drive sealing device form is difficult to meet the increasing demand for resisting external high confining pressure.

[0005] In the prior art, there is a lack of a sealing device that can actively adjust the sealing contact stress according to the ambient pressure to reduce dynamic friction and wear at normal pressure or low pressure to extend the sealing life, and increase the sealing contact stress at high confining pressure in emergency situations to achieve a good static sealing effect to protect the main bearing of the core component from load impact. Summary of the invention

[0006] In order to solve the problem in the prior art that the sealing system of a shaft boring machine cannot adjust the sealing contact stress according to the ambient pressure, resulting in a short service life of the sealing device or a poor sealing effect, an embodiment of the present invention provides a shaft boring machine and its sealing system, and a combined sealing device with active pressure compensation.

[0007] According to one aspect of the present invention, there is provided a combined sealing device for active pressure compensation, which can isolate a first space and a second space at both ends of a sealing channel, and comprises a main sealing body and a sealing pressure ring, wherein one side of the main sealing body is a sealing part and the other side is a pressure regulating part; the sealing pressure ring is connected to the first side wall of the sealing channel and forms a gap with the second side wall; the sealing pressure ring and the first side wall together form a accommodating space for the pressure regulating part, so that the pressure regulating part abuts against the first side wall in the accommodating space, and the sealing part abuts against the second side wall through the accommodating space; a pressure regulating chamber is also provided on the side of the pressure regulating part close to the first side wall, and the gap distance or contact stress between the sealing part and the second side wall can be changed by changing the pressure in the pressure regulating chamber; the outer contour of the sealing part close to the first space is an arc-shaped structure protruding outward, so that the gap between the side of the sealing part close to the first space and the second side wall gradually decreases.

[0008] Furthermore, the outer contour of the sealing portion near the second space is an inwardly concave arc-shaped structure, and forms a sharp-angle structure with the outer contour of the sealing portion near the first space, so that the sharp corner faces the external space.

[0009] Furthermore, the outer contour of the sealing portion close to the first space also includes a straight area connected to the arc-shaped structure, and the straight area abuts against the second side wall to increase the sealing contact area between the sealing portion and the second side wall.

[0010] Furthermore, both sides of the pressure regulating part are protruding from the sealing part to form raised parts on both sides of the pressure regulating part; the sealing pressure ring includes an inner sealing pressure ring and an outer sealing pressure ring, the inner sealing pressure ring and the outer sealing pressure ring are arranged opposite to each other at intervals, and the inner sealing pressure ring and the outer sealing pressure ring are both provided with raised parts on the side close to the second side wall, the raised parts of the inner sealing pressure ring and the outer sealing pressure ring are close to each other, so as to form a accommodating space matching the shape of the pressure regulating part together with the first side wall, so that the raised parts on both sides of the pressure regulating part are confined in the accommodating space; the two sides of the sealing part are respectively abutted against the raised parts of the inner sealing pressure ring and the outer sealing pressure ring, and extend outward from the gap between the raised parts of the inner sealing pressure ring and the outer sealing pressure ring, so that the end of the sealing part abuts against the second side wall.

[0011] Another aspect of the present invention provides a sealing system for a shaft boring machine, comprising the combined sealing device described in the above items, wherein the shaft boring machine comprises a swivel flange connected to a rotating body of the shaft boring machine and a sealing support arranged opposite to the swivel flange, a sealing channel is formed between the swivel flange and the sealing support, an outer side wall of the swivel flange is a second side wall of the sealing channel, an inner side wall of the sealing support is a first side wall of the sealing channel, an inner space of the shaft boring machine is used as a first space, and an outer space of the shaft boring machine is used as a second space, and the combined sealing device is used to isolate and seal the inner space and the outer space of the shaft boring machine.

[0012] Furthermore, the sealing system further comprises a second sealing component arranged near the internal space, the second sealing component being a single-lip sealing structure or a multi-lip sealing structure, one side of the second sealing component being fixedly connected to the second side wall, and the other side of the second sealing component being in contact with the first side wall to seal the sealing channel, the second sealing component and the combined sealing device isolating the sealing channel from the first cavity, and the first cavity can contain sealing grease; When the pressure of the external space is lower than the preset pressure threshold, the sealing of the sealing channel is realized by the second sealing assembly, and the pressure in the pressure regulating chamber of the combined sealing device can be reduced, so that a clearance fit is formed between the sealing portion of the combined sealing device and the second side wall, and the pressure of the internal space, the first chamber and the external space is in a step-down trend, so that the material in the first chamber can flow out through the gap between the combined sealing device and the first side wall; When the external space pressure exceeds a preset pressure threshold, the pressure in the pressure regulating chamber of the combined sealing device can be increased according to the sealing correspondence between the pressure regulating chamber of the combined sealing device and the external space pressure, so that the sealing part of the combined sealing device and the second side wall are interference fit to seal the sealing channel.

[0013] Furthermore, the sealing system of the shaft boring machine also includes a second combined sealing device arranged between the combined sealing device and the second sealing assembly. The second combined sealing device has the same structure as the combined sealing device. When the external space pressure exceeds a preset pressure threshold and the combined sealing device fails, the pressure in the pressure regulating chamber of the second combined sealing device can be increased according to the sealing correspondence between the pressure regulating chamber of the second combined sealing device and the external space pressure, so that the sealing part of the second combined sealing device and the second side wall are interference fit to seal the sealing channel.

[0014] Furthermore, an L-shaped sealing gap is formed between the swivel flange and the sealing support, and the second sealing component and the combined sealing device are respectively arranged on both sides of the L-shaped sealing gap.

[0015] Furthermore, the sealing support is provided with a first active compensation conduit leading to the pressure regulating chamber of the combined sealing device and a second active compensation conduit leading to the pressure regulating chamber of the second combined sealing device; The second combined sealing device divides the first cavity into a second cavity and a third cavity, and the sealing support is provided with a first back pressure compensation pipeline leading to the second cavity and a second back pressure compensation pipeline leading to the third cavity; The sealing support is also provided with a water injection cavity close to the second sealing component, and a water inlet channel and a water outlet channel communicating with the water injection cavity.

[0016] Another aspect of the present invention provides a shaft boring machine, comprising the sealing system for the shaft boring machine as described above.

[0017] The combined sealing device with active pressure compensation provided by the present invention has the following beneficial effects: 1. The main sealing body includes a sealing part and a pressure regulating part. The sealing pressure ring limits the pressure regulating part to abut against the first side wall. By changing the pressure in the pressure regulating chamber, the contact stress between the sealing part and the second side wall can be changed, so as to adapt to different external pressures. Not only can a better sealing effect be achieved for higher external pressures, but also a material discharge channel can be formed between the main sealing body and the second side wall when the external pressure is relatively low. 2. The outer contour of the sealing part close to the internal space is an arc-shaped structure protruding outward, and the top of the arc-shaped structure abuts against the second side wall, so that the gap between the side of the sealing part close to the internal space and the second side wall is gradually reduced, so that when the sealing part and the second side wall are in a gap fit, the substances in the internal space, especially the impurities in the internal space, can be more easily discharged through the gap between the sealing part and the second side wall; 3. The outer contour of the sealing part close to the external space is an inwardly concave arc structure, and forms a sharp-angle structure with the outer contour of the sealing part close to the internal space, so that the sharp angle faces the external space. The sharp-angle structure can not only effectively prevent the material in the external space from entering the internal space, but also further increase the contact stress between the sealing part and the second side wall when the external pressure is large. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 is a schematic structural diagram of a combined sealing device for active pressure compensation provided by an embodiment of the present invention; Figure 2 is a schematic diagram of contact stress simulation results of a combined sealing device provided by an embodiment of the present invention; Figure 3 A test bench for the combined sealing device provided in an embodiment of the present invention; Figure 4 is a cross-sectional view of a test bench for a combined sealing device provided by an embodiment of the present invention; Figure 5 is a system diagram of a test experiment of a combined sealing device provided by an embodiment of the present invention; Figure 6 is a cross-sectional view of a sealing system of a shaft boring machine provided by an embodiment of the present invention; Figure 7is another cross-sectional view of a sealing system of a shaft boring machine provided by an embodiment of the present invention; Figure 8 The diagram is a top view of a partial structure of a sealing system of a shaft boring machine provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0020] In order to make the technical problems, technical solutions and advantages to be solved by the present invention more clear, a detailed description will be given below with reference to the accompanying drawings and specific embodiments.

[0021] The specific structure of the combined sealing device for active pressure compensation (hereinafter referred to as the combined sealing device) provided by the embodiment of the present invention is as follows: Figure 1 As shown, the combined sealing device is arranged in a sealing channel, and can isolate the first space and the second space at both ends of the first channel, wherein the first space and the second space can be the internal space and the external space of a certain device, so as to effectively isolate the internal space and the external space, or can be other two spaces that need to be isolated. In addition, the combined sealing device of active pressure compensation provided in the embodiment of the present invention can also seal the rotating device to ensure the sealing of the internal and external spaces of the rotating device. It can be understood that the sealing device provided in the embodiment of the present invention can be applied not only to the sealing system of the shaft boring machine, but also to the structure with similar sealing channels.

[0022] Furthermore, Figure 1 A sealing channel is formed by the first support 8 and the second support 7, the inner side wall of the first support 8 is the first side wall, and the inner side wall of the second support 7 is the second side wall. It can be understood that the combined sealing device of the embodiment of the present invention is arranged in the sealing channel formed by the first side wall and the second side wall, and the structure to which the first side wall and the second side wall belong may be different according to the application scenario. In a specific embodiment of the present invention, the first support 8 is a sealing support, and the second support 7 is a rotatable swivel flange. In addition, for the convenience of description, the present invention takes the extension direction of the sealing channel to the inner and outer sides as the length direction of the sealing channel, and the relative direction of the two side walls as the width direction of the sealing channel.

[0023] Furthermore, the combined sealing device provided in the embodiment of the present invention includes a main sealing body 1 and a sealing pressure ring, wherein the width of the main sealing body 1 is slightly smaller than the width of the sealing channel, so that one side of the width direction of the main sealing body 1 abuts against the first side wall, and the other side abuts against the second side wall. More specifically, since the width of the sealing channel may also increase with the increase of pressure, the main sealing body 1 and the sealing channel in the embodiment of the present invention are transitionally matched, and can be switched between clearance fit and interference fit according to different compensation pressures. The sealing pressure ring is fixedly connected to the first side wall by bolts, and a gap is formed between the sealing pressure ring and the second side wall, and the gap is filled by the main sealing body 1.

[0024] Specifically, the main sealing body 1 can be divided into a sealing part 11 and a pressure regulating part 12. The sealing part 11 and the pressure regulating part 12 extend along the width direction of the sealing channel. The sealing pressure ring is connected to the first side wall and together with the first side wall forms a accommodating space for the pressure regulating part 12. The pressure regulating part 12 fills the accommodating space so that the pressure regulating part 12 abuts against the first side wall in the accommodating space, and the sealing part 11 passes through the accommodating space and abuts against the second side wall.

[0025] It should be noted that, although the pressure regulating part 12 in the embodiment of the present invention is filled in the accommodating space, since the pressure regulating part 12 itself is not fixed by fixing devices such as bolts, the pressure regulating part 12 may produce a slight displacement in the accommodating space.

[0026] Refer to the attached Figure 1 , the pressure regulating part 12 is protruding from the sealing part 11 on both sides of the length direction of the main sealing body 1 to form raised parts on both sides of the pressure regulating part 12, so that the overall outline of the main sealing body 1 is similar to a convex shape; the sealing pressure ring includes an inner sealing pressure ring 2 and an outer sealing pressure ring 3, the inner sealing pressure ring 2 and the outer sealing pressure ring 3 are arranged opposite to each other at intervals, and the inner sealing pressure ring 2 and the outer sealing pressure ring 3 are also provided with raised parts on the side close to the second side wall, the raised parts of the inner sealing pressure ring 2 and the outer sealing pressure ring 3 are close to each other, and together with the first side wall, they constitute an accommodating space matching the shape of the pressure regulating part 12, so that the raised parts on both sides of the pressure regulating part 12 are limited in the accommodating space; the two sides of the sealing part 11 are respectively abutted against the raised parts of the inner sealing pressure ring 2 and the outer sealing pressure ring 3, and extend outward from the gap between the raised parts of the inner sealing pressure ring 2 and the outer sealing pressure ring 3, so that the end of the sealing part 11 is abutted against the second side wall. That is, the accommodation space formed by the inner sealing ring 2, the outer sealing ring 3 and the first side wall is a convex structure matching the shape of the main sealing body 1, and an opening is formed at the upper end of the convex structure for the sealing part 11 to pass through the accommodation space and abut against the second side wall. Therefore, when the pressure regulating part 12 is slightly displaced in the accommodation space, the gap distance or contact stress between the sealing part 11 and the second side wall can be changed.

[0027] Based on the above structural features, a pressure regulating chamber 13 is further provided at one end of the pressure regulating portion 12 close to the first side wall, and the gap distance or contact stress between the sealing portion 11 and the second side wall can be changed by changing the pressure in the pressure regulating chamber 13. Therefore, it can be understood that the sealing portion 11 and the second side wall can be switched between clearance fit and interference fit by changing the pressure in the pressure regulating chamber 13, and the gap between the two can be changed in the case of clearance fit, and the contact stress between the two can be changed in the case of interference fit.

[0028] It is understandable that when the pressure in the sealing channel is high, especially when the pressure difference between the spaces on both sides of the combined sealing device is large, the excessive pressure will cause the gap in the sealing channel to increase, thereby reducing the contact stress between the sealing portion 11 and the second side wall, and even causing a gap between the two, ultimately causing sealing failure. The present invention provides compensation pressure for the sealing portion 11 through the pressure regulating chamber 13, so that it moves further toward the second side wall, thereby compensating for the sealing loss caused by the excessive pressure in the sealing channel, thereby achieving a better sealing effect.

[0029] By the attached Figure 1 As shown, when the pressure in the pressure regulating chamber 13 is increased, the main sealing body 1 as a whole will move toward the second side wall along with the compensation pressure in the pressure regulating chamber 13, increasing the contact stress between the sealing portion 11 and the second side wall. At this time, since the sealing pressure ring is tightly connected to the first side wall, the sealing pressure ring and the main sealing body 1 jointly seal the sealing channel. When the ambient pressure of the second space increases, the pressure in the pressure regulating chamber 13 is increased accordingly, and the seal can be further compensated to achieve a good sealing effect. Therefore, the pressure in the pressure regulating chamber 13 is also called the compensation pressure.

[0030] Specifically, the cross section of the pressure regulating chamber 13 is an arc-shaped structure close to the first side wall, and the pressure regulating chamber 13 can be provided with a compensation pressure by introducing hydraulic oil into the pressure regulating chamber 13. The arc-shaped structure can make the pressure in the pressure regulating chamber 13 more uniform. In addition, in order to facilitate the introduction of hydraulic oil into the pressure regulating chamber 13, a pressure regulating channel 9 connected to the pressure regulating chamber 13 is also provided on the first side wall, and hydraulic oil or other liquid is transported into the pressure regulating chamber 13 through the pressure regulating channel 9 to change the pressure of the pressure regulating chamber 13.

[0031] Furthermore, the outer contour of the sealing portion 11 near the first space is an arc-shaped structure protruding outward, and the arc-shaped structure can be a circular arc segment, or other arc segments with gradually changing curvatures, wherein the top of the arc-shaped structure abuts against the second side wall, and at this time, the gap between the side of the sealing portion 11 near the first space and the second side wall gradually decreases, forming a guide channel for flow from the first space to the second space. When the space pressure of the first space is greater than that of the second space, and there is a gap between the sealing portion 11 and the second side wall, impurities in the first space can enter the second space more smoothly through the arc-shaped structure.

[0032] It should be noted here that Figure 1 The radial cross-sectional view of the combined sealing device. The sealing device as a whole can be a circular ring structure. The specific structure can be referred to Figure 3 , Figure 4The combined sealing device with an annular structure can seal both the inner and outer sides of the rotating shaft. In addition, the combined sealing device can also be in other shapes, as long as the cross-sectional shape is Figure 1 The structure shown can achieve the sealing of the corresponding channel.

[0033] In a specific embodiment of the present invention, the first space is an internal space, and the second space is an external space. When the pressure of the internal space is higher than that of the external space, the pressure in the pressure regulating chamber 13 can be reduced to create a gap between the sealing portion 11 and the second side wall, thereby discharging impurities in the internal space into the external space.

[0034] Furthermore, the outer contour of the sealing portion 11 on the side close to the second space is an inwardly concave arc-shaped structure, and forms a sharp angle structure with the outer contour of the sealing portion 11 on the side close to the first space, so that the sharp angle faces the second space. The arc-shaped structure close to the second space can effectively prevent the material in the second space from entering the first space, and when the pressure in the second space is too high, the contact stress between the sealing portion 11 and the second side wall can be increased.

[0035] Specifically, as attached Figure 1 As shown, the sealing portion 11 is similar to a blade-shaped structure as a whole. In a specific embodiment of the present invention, the arc surface of the blade-shaped structure close to the first space is tangent to the second side wall, so that the pressure fluid in the first space can be easily pressed thereon to form an outward gap, and the impurities entering the first space can be promptly discharged to the second space through the gap; the arc surface of the blade-shaped structure facing the second space is perpendicular to the contact part of the second side wall, so that under the cooperation of the compensation pressure, it is difficult for the fluid in the second space to enter the first space to form a sealing effect.

[0036] Figure 2 FIG. 4 shows a schematic diagram of a simulation of contact stress in an embodiment of the present invention. Figure 2 The abscissa of the middle curve is the contact distance between the sealing portion 11 and the second side wall, and the ordinate is the contact stress between the sealing portion 11 and the second side wall. Figure 2 (a) is the stress change between the sealing portion 11 and the second side wall when the internal space pressure is 0, the compensation pressure of the pressure regulating chamber 13 is 1.0 MPa, and the external space pressure is gradually increased; Figure 2 (b) shows the stress change between the sealing part 11 and the second side wall when the external space pressure is 0, the compensation pressure of the pressure regulating chamber 13 is 1.0 MPa, and the internal space pressure is gradually increased. Figure 2 It can be seen that when the external space pressure is relatively high, the structure of the sealing portion 11 can effectively increase the contact stress between the sealing portion 11 and the second side wall, thereby achieving a good sealing effect. This effect also meets the requirement that it is difficult for external fluid to enter the interior through the gap, while the internal fluid can easily flow out to remove impurities.

[0037] Furthermore, the outer contour of the sealing portion 11 close to the first space also includes a straight area connected to the arc-shaped structure, and the straight area abuts against the second side wall to increase the sealing contact area between the sealing portion 11 and the second side wall, thereby further improving the sealing effect.

[0038] In addition, in the embodiment of the present invention, the contact portion between the sealing ring and the sealing portion 11 adopts an arc transition, and the sealing ring is an outwardly protruding arc structure at the contact portion, and the sealing portion 11 is an inwardly recessed arc structure. At this time, the specific structure of the side of the sealing portion 11 facing the first space is two sections of mutually circumscribed arcs, and the specific structure of the side of the sealing portion 11 facing the second space is a whole section of an inwardly recessed arc structure. This structure can not only make the contact stress between the main sealing body 1 and the sealing ring more uniform, but also be more conducive to the sealing ring limiting the main sealing body 1.

[0039] Furthermore, the combined sealing device provided in an embodiment of the present invention also includes a corresponding sealing ring structure, wherein a first sealing groove for accommodating a first sealing ring 4 is provided on a side of the pressure regulating part 12 close to the first side wall, and the first sealing ring 4 is used to form a seal between the pressure regulating part 12 and the first side wall; and / or a second sealing groove for accommodating a second sealing ring 5 is provided on a side of the sealing pressure ring close to the first side wall, and the second sealing ring 5 is used to form a seal between the sealing pressure ring and the first side wall; and / or a third sealing groove for accommodating a third sealing ring 6 is provided on the side of the sealing pressure ring close to the pressure regulating part 12, or on the side of the pressure regulating part 12 close to the sealing pressure ring, and the third sealing ring 6 is used to form a seal between the sealing pressure ring and the pressure regulating part 12.

[0040] It should be noted that each of the above sealing rings can select a series of O-rings made of corresponding materials according to the use requirements. When the required pressure is low, the softer nitrile rubber series can be selected. When the required pressure is high, the harder fluororubber series can be selected, and even a retaining ring can be configured to enhance the sealing effect. In order to increase the sealing effect, each sealing ring and the contact surface are interference fit.

[0041] In addition, the preferred embodiment of the present invention is that three kinds of sealing rings are used at the same time. After the first sealing ring 4 fails due to various reasons, the second sealing ring 5 and the third sealing ring 6 can continue to play a sealing effect, thereby enhancing the safety of the seal. In addition, if the second sealing ring and the third sealing ring are made of metal materials, the pressure bearing capacity of the bottom cavity of the sealing device can be further enhanced, that is, the sealing pressure between the main sealing body 1 and the second side wall surface is increased, and the pressure bearing capacity of the seal is further enhanced. In addition, in the preferred embodiment of the present invention, the main sealing body 1 is a PTFE series special-shaped seal.

[0042] In addition, in order to further obtain the corresponding relationship of the sealing pressure of the combined sealing device of the present invention, the embodiment of the present invention also provides the following Figure 3-Figure 5 The seal pressure bearing capacity test system shown in the figure includes a seal test bench module 101, which is used to accommodate the combined seal device and carry out a series of seal pressure bearing tests; a pressure supply system module 102, which is used to provide the external pressure and compensation pressure required for simulation into the test bench; and a data acquisition module 103, which is used to obtain the signal data required for analysis during the test.

[0043] like Figure 3 and Figure 4 As shown, the sealing test bench module 101 of the present invention includes an end cover 21 and a base 22, which are buckled together to form a sealing groove to simulate a sealing channel. Specifically, the present invention buckles and presses the end cover 21 and the base 22 through a plurality of connecting bolts 23 in the circumferential direction of the end cover 21. In addition, in order to increase the sealing effect, an end face sealing ring is also provided.

[0044] Specifically, Figure 4 As shown, a rectangular sealing groove is formed on the flange of the base 22 and the contact side of the end cover 21. The groove is an annular cavity with a rectangular cross section. The combined sealing device is filled in the sealing groove. The sealing device divides the sealing groove into an inner chamber 27 and an outer chamber 26.

[0045] Furthermore, a through hole is opened in the center and the periphery of the end cover 21 respectively. The first through hole 24 of the end cover is opened above the internal chamber 27 and can be idle or introduced inward to introduce the sensor to test the contact stress change of the sealing contact surface. The second through hole 25 of the end cover is opened above the external chamber 26.

[0046] Correspondingly, three through holes are opened in the center and periphery of the base 22. The first through hole 29 of the base is opened below the internal chamber 27, which is used to lead out a pipeline to the outside to collect the liquid generated by leakage. The second through hole 28 of the base is opened below the external chamber 26, and the third through hole 210 of the base is opened below the pressure regulating chamber 13.

[0047] Furthermore, the pressure supply system module 102 includes a hydraulic oil pump 32, a hydraulic water pump 31 and matching high-pressure pipelines. The hydraulic water pump 31 is connected to the second through hole 28 of the sealing test bench base through the first high-pressure pipeline, and provides the external pressure required for the test to the external chamber 26 through the first high-pressure pipeline. The hydraulic oil pump 31 is connected to the third through hole 210 of the sealing test bench base through the second high-pressure pipeline, and provides the compensation pressure required for the test to the pressure regulating chamber 13 through the second high-pressure pipeline.

[0048] Furthermore, the data acquisition module 103 includes a beaker 35, an inner cavity sensing device 34 and an outer cavity pressure sensor (including digital display) 36. The inner cavity sensing device 34 specifically includes a mass sensor and a digital display controller pressure regulating chamber 13 pressure sensor (including digital display) 33. The beaker 35 is connected to the first through hole 29 of the base, and is used to collect the liquid generated by the leakage of the internal chamber 27. The mass sensor is a membrane box type weighing force sensor, which is placed at the bottom of the beaker 35 and is used to collect the leakage liquid mass signal data generated in the internal chamber 27 during the test and changes with time. The digital display controller is used to convert the mass analog signal into a digital signal for display.

[0049] Furthermore, the external cavity pressure sensor 36 is arranged on the second through hole 25 of the end cover, and is used to collect the pressure signal that changes with time in the external cavity 26 and display it through a digital display. The pressure sensor 33 of the pressure regulating cavity 13 is arranged on the second high-pressure pipeline between the hydraulic oil pump 32 and the third through hole 210 of the base, and is used to collect the pressure signal that changes with time in the pressure regulating cavity 13 and display it through a digital display.

[0050] Furthermore, during the test, after the specified oil pressure is injected into the pressure regulating chamber 13 through the hydraulic oil pump 32, the pressure is maintained unchanged, and water pressure is slowly injected into the external chamber 26 through the hydraulic water pump 21 until the pressure no longer increases and the liquid generated by the leakage is collected in the beaker 35 connected to the first through hole 29 of the base, causing the numerical control display to change the reading and stop pressurizing. The readings on the external cavity pressure sensor 26 and the bottom cavity pressure sensor 33 at this time are recorded, and the pressure bearing capacity of the combined sealing device to the external load under the compensation pressure can be obtained through the data acquisition module 103. The compensation pressure is changed, and the compensation pressure reading is recorded through the bottom cavity pressure sensor 33. The above operation is repeated to obtain the maximum external pressure bearing capacity corresponding to different compensation pressures, and the corresponding relationship between the compensation pressure and the sealing pressure of the combined sealing device can be obtained, that is, the sealing correspondence between the pressure regulating chamber of the sealing device and the external space pressure.

[0051] like Figure 6 , Figure 7 As shown, an embodiment of the present invention further provides a sealing system for a shaft boring machine, wherein the shaft boring machine comprises a swivel flange 44 connected to a rotating body of the shaft boring machine and a sealing support 45 arranged opposite to the swivel flange 44, a sealing channel is formed between the swivel flange 44 and the sealing support 45, an outer side wall of the swivel flange 44 is a second side wall of the sealing channel, an inner side wall of the sealing support 45 is a first side wall of the sealing channel, an inner space of the shaft boring machine is used as a first space, an outer space of the shaft boring machine is used as a second space, and a combined sealing device is used to seal the inner space and the outer space of the shaft boring machine.

[0052] Furthermore, the sealing system also includes a second sealing component 42 arranged close to the internal space. The second sealing component 42 is a single-lip sealing structure or a multi-lip sealing structure. One side of the second sealing component 42 is fixedly connected to the second side wall, and the other side abuts against the first side wall to seal the sealing channel. The second sealing component 42 and the combined sealing device isolate the sealing channel from the first cavity, and the first cavity can accommodate sealing grease.

[0053] The sealing system of the shaft boring machine in the embodiment of the present invention realizes the sealing of the shaft boring machine by the cooperation between the second sealing assembly 42 and the combined sealing device.

[0054] Specifically, when the pressure of the external space is lower than the preset pressure threshold, the sealing of the sealing channel is realized by the second sealing component 42, and the pressure in the pressure regulating chamber 13 of the combined sealing device can be reduced, so that the sealing part 11 of the combined sealing device and the second side wall are in a clearance fit, and the pressure of the internal space, the first chamber and the external space is in a step-down trend, so that the material in the first chamber flows out through the gap between the combined sealing device and the first side wall; when the pressure of the external space exceeds the preset pressure threshold, the pressure in the pressure regulating chamber 13 of the combined sealing device can be increased according to the sealing correspondence between the pressure regulating chamber 13 of the combined sealing device and the pressure of the external space, so that the sealing part 11 of the combined sealing device and the second side wall are in an interference fit, so as to seal the sealing channel. The sealing correspondence between the pressure regulating chamber 13 of the sealing device and the pressure of the external space is the corresponding relationship between the compensation pressure and the sealing pressure of the combined sealing device obtained in the above test. The present invention can adjust the compensation pressure of the combined sealing device in a step-by-step manner according to the pressure of the external space, which can not only achieve the effect of effective sealing, but also minimize the compensation pressure of the combined sealing device, reduce the contact stress between the mechanical components, and improve the service life of the combined sealing device.

[0055] Furthermore, in order to achieve a better sealing effect, in an embodiment of the present invention, the sealing system of the shaft boring machine also includes a second combined sealing device 44 arranged between the combined sealing device and the second sealing assembly 42. The second combined sealing device 44 has the same structure as the combined sealing device. When the external space pressure exceeds a preset pressure threshold and the combined sealing device fails, the pressure in the pressure regulating chamber 13 of the second combined sealing device 44 can be increased according to the sealing correspondence between the pressure regulating chamber 13 of the second combined sealing device 44 and the external space pressure, so that the sealing portion 11 of the second combined sealing device and the second side wall are interference fit to seal the sealing channel.

[0056] Furthermore, in order to reasonably arrange each sealing device, the rotary flange 44 and the sealing support 45 form an L-shaped sealing gap, and the second sealing component 42 and the combined sealing device are respectively arranged on both sides of the L-shaped sealing gap. The tortuous sealing channel design also causes the external fluid to produce along-the-way loss when entering the corner, which reduces the impact on the subsequent sealing structure and buys time for the secondary pressure compensation effect to be produced, thereby playing a double role of protection. At the same time, due to the high ambient pressure, the dynamic operation of the seal needs to be interrupted, and the seal enters the static sealing state to prevent the high wear state during the rotation due to excessive contact torque, so as to achieve zero leakage sealing against external high pressure.

[0057] Furthermore, a first active compensation pipe 51 leading to the pressure regulating chamber 13 of the combined sealing device and a second active compensation pipe 52 leading to the pressure regulating chamber 13 of the second combined sealing device 43 are provided on the sealing support; the second combined sealing device 43 divides the first cavity into a second cavity and a third cavity, and a first back pressure compensation pipe 54 leading to the second cavity and a second back pressure compensation pipe 55 leading to the third cavity are provided on the sealing support 45; the sealing support 45 is also provided with a water injection cavity 48 close to the second sealing assembly 42, and a water inlet channel and a water outlet channel 53 connecting the water injection cavity 48.

[0058] It should be noted here that Figure 7 and Figure 8 The combined sealing device of the shaft boring machine is a circular ring structure around the rotating shaft, and each channel is as follows Figure 8 As shown, the channels are distributed on the annular end surface of the sealing support 45. In order to facilitate the description of the direction of each channel, different channels are drawn on the same cross section. In fact, each channel is distributed along the annular space at intervals, and each channel is independent of each other. Figure 8 shown.

[0059] In a specific embodiment of the present invention, when the pressure of the external space is lower than a preset pressure threshold, oil pressure is injected into the first back pressure compensation pipe 54 and the second back pressure compensation pipe 55, so that the pressure between the external space, the second cavity and the third cavity tends to rise in a step-by-step manner, and the first active compensation pipe 51 and the second active compensation pipe 52 do not perform pressure compensation. At this time, the sealing of the sealing channel is realized by the second sealing assembly 42, so that the sealing part 11 of the combined sealing device, the sealing part of the second combined sealing device 43 and the second side wall are gap-fitted, so that the substances in the second chamber and the third chamber can flow out through the gap between the combined sealing device and the first side wall; when the pressure of the external space exceeds the preset pressure threshold, the pressure in the pressure regulating chamber 13 of the combined sealing device can be increased through the first active compensation pipe 51 according to the sealing correspondence between the pressure regulating chamber 13 of the combined sealing device and the external space pressure, so that the sealing part 11 of the combined sealing device and the second side wall are interference-fitted to seal the sealing channel. The sealing correspondence between the pressure regulating chamber 13 of the sealing device and the pressure of the external space is the corresponding relationship between the compensation pressure and the sealing pressure of the combined sealing device obtained in the above test. When the combined sealing device fails, the pressure in the pressure regulating chamber 13 of the second combined sealing device 43 is increased through the second active compensation pipe 52, so that the sealing portion 11 of the second combined sealing device 43 and the second side wall are interference fit to seal the sealing channel.

[0060] In addition, one aspect of the present invention provides a shaft boring machine, comprising the sealing system of the shaft boring machine described in the above embodiment.

[0061] The shaft boring machine and its sealing system, and the combined sealing device with active pressure compensation provided by the present invention have the following beneficial effects: 1. The main sealing body 1 includes a sealing part 11 and a pressure regulating part 12. The sealing pressure ring limits the pressure regulating part 12 to abut against the first side wall. The contact stress between the sealing part 11 and the second side wall can be changed by changing the pressure in the pressure regulating chamber 13, so as to adapt to different external pressures. Not only can a better sealing effect be achieved for higher external pressures, but also a material discharge channel can be formed between the main sealing body 1 and the second side wall when the external pressure is relatively low. 2. The outer contour of the sealing portion 11 close to the internal space is an arc-shaped structure protruding outward, and the top of the arc-shaped structure abuts against the second side wall, so that the gap between the side of the sealing portion 11 close to the internal space and the second side wall is gradually reduced, so that when the sealing portion 11 and the second side wall are in a gap fit, the substances in the internal space, especially the impurities in the internal space, can be more easily discharged through the gap between the sealing portion 11 and the second side wall; 3. The outer contour of the sealing portion 11 close to the external space is an inwardly concave arc-shaped structure, and forms a sharp angle structure with the outer contour of the sealing portion 11 close to the internal space, so that the sharp angle faces the external space. The sharp angle structure can not only effectively prevent the substances in the external space from entering the internal space, but also further increase the contact stress between the sealing portion 11 and the second side wall when the external pressure is large; 4. The sealing system of the shaft boring machine can select the sealing method according to the external environmental pressure, which is not only conducive to the sealing system to discharge impurities in the internal space in time, but also can effectively seal the internal space when the external environmental pressure is high. It has a stronger ability to adapt to the external environmental pressure, further protecting the safe operation of the shaft boring machine.

[0062] The present invention is further described above with the help of specific embodiments, but it should be understood that the specific description here should not be understood as limiting the essence and scope of the present invention. Various modifications made to the above embodiments by ordinary technicians in this field after reading this specification belong to the scope of protection of the present invention. The various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the embodiments of the present invention will not be described separately for various possible combinations.

[0063] If an embodiment of the present invention involves directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

Claims

1. An active pressure compensation combined sealing device, arranged in a sealing channel, can isolate a first space and a second space at both ends of the sealing channel, characterized in that: It includes a main sealing body and a sealing pressure ring, one side of the main sealing body is a sealing part, and the other side is a pressure regulating part; the sealing pressure ring is connected to the first side wall of the sealing channel and forms a gap with the second side wall; the sealing pressure ring and the first side wall together form a accommodating space for the pressure regulating part, so that the pressure regulating part abuts against the first side wall in the accommodating space, and the sealing part passes through the accommodating space and abuts against the second side wall; a pressure regulating chamber is also provided on the side of the pressure regulating part close to the first side wall, and the gap distance or contact stress between the sealing part and the second side wall can be changed by changing the pressure in the pressure regulating chamber; the outer contour of the sealing part close to the first space is an arc-shaped structure protruding outward, so that the gap between the side of the sealing part close to the first space and the second side wall gradually decreases.

2. The combined sealing device according to claim 1, characterized in that: The outer contour of the sealing portion near the second space is an inwardly concave arc-shaped structure, and forms a sharp angle structure with the outer contour of the sealing portion near the first space, so that the sharp angle faces the external space.

3. The combined sealing device according to claim 1 or 2, characterized in that: The outer contour of the sealing portion close to the first space also includes a straight area connected to the arc-shaped structure, and the straight area abuts against the second side wall to increase the sealing contact area between the sealing portion and the second side wall.

4. The combined sealing device according to claim 2, characterized in that: The two sides of the pressure regulating part protrude from the sealing part to form raised parts on both sides of the pressure regulating part; the sealing pressure ring includes an inner sealing pressure ring and an outer sealing pressure ring, the inner sealing pressure ring and the outer sealing pressure ring are arranged opposite to each other at intervals, and the inner sealing pressure ring and the outer sealing pressure ring are both provided with raised parts on the side close to the second side wall, the raised parts of the inner sealing pressure ring and the outer sealing pressure ring are close to each other, so as to form a accommodating space matching the shape of the pressure regulating part together with the first side wall, so that the raised parts on both sides of the pressure regulating part are confined in the accommodating space; the two sides of the sealing part are respectively abutted against the raised parts of the inner sealing pressure ring and the outer sealing pressure ring, and extend outward from the gap between the raised parts of the inner sealing pressure ring and the outer sealing pressure ring, so that the end of the sealing part abuts against the second side wall.

5. A sealing system for a shaft boring machine, characterized in that: The invention comprises the combined sealing device described in any one of claims 1 to 4, wherein the shaft boring machine comprises a swivel flange connected to the rotating body of the shaft boring machine and a sealing support arranged opposite to the swivel flange, a sealing channel is formed between the swivel flange and the sealing support, the outer side wall of the swivel flange is the second side wall of the sealing channel, the inner side wall of the sealing support is the first side wall of the sealing channel, the inner space of the shaft boring machine is used as the first space, and the outer space of the shaft boring machine is used as the second space, and the combined sealing device is used to isolate and seal the inner space and the outer space of the shaft boring machine.

6. The sealing system for a shaft boring machine according to claim 5, characterized in that: The sealing system further includes a second sealing component arranged near the internal space, the second sealing component is a single-lip sealing structure or a multi-lip sealing structure, one side of the second sealing component is fixedly connected to the second side wall, and the other side abuts against the first side wall to seal the sealing channel, the second sealing component and the combined sealing device isolate the sealing channel from the first cavity, and the first cavity can contain sealing grease; When the pressure of the external space is lower than the preset pressure threshold, the sealing of the sealing channel is realized by the second sealing assembly, and the pressure in the pressure regulating chamber of the combined sealing device can be reduced, so that a clearance fit is formed between the sealing portion of the combined sealing device and the second side wall, and the pressure of the internal space, the first chamber and the external space is in a step-down trend, so that the material in the first chamber can flow out through the gap between the combined sealing device and the first side wall; When the external space pressure exceeds a preset pressure threshold, the pressure in the pressure regulating chamber of the combined sealing device can be increased according to the sealing correspondence between the pressure regulating chamber of the combined sealing device and the external space pressure, so that the sealing part of the combined sealing device and the second side wall are interference fit to seal the sealing channel.

7. The sealing system of a shaft boring machine according to claim 5, characterized in that: The sealing system of the shaft boring machine also includes a second combined sealing device arranged between the combined sealing device and the second sealing assembly. The second combined sealing device has the same structure as the combined sealing device. When the external space pressure exceeds a preset pressure threshold and the combined sealing device fails, the pressure in the pressure regulating chamber of the second combined sealing device can be increased according to the sealing correspondence between the pressure regulating chamber of the second combined sealing device and the external space pressure, so that the sealing part of the second combined sealing device and the second side wall are interference fit to seal the sealing channel.

8. The sealing system of a shaft boring machine according to claim 6 or 7, characterized in that: An L-shaped sealing gap is formed between the swivel flange and the sealing support, and the second sealing component and the combined sealing device are respectively arranged on both sides of the L-shaped sealing gap.

9. The sealing system for a shaft boring machine according to claim 6, characterized in that: The sealing support is provided with a first active compensation pipeline leading to the pressure regulating chamber of the combined sealing device and a second active compensation pipeline leading to the pressure regulating chamber of the second combined sealing device; The second combined sealing device divides the first cavity into a second cavity and a third cavity, and the sealing support is provided with a first back pressure compensation pipeline leading to the second cavity and a second back pressure compensation pipeline leading to the third cavity; The sealing support is also provided with a water injection cavity close to the second sealing component, and a water inlet channel and a water outlet channel communicating with the water injection cavity.

10. A shaft boring machine, characterized in that: A sealing system for a shaft boring machine comprising any one of claims 5-9.

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