Mechanical seal device capable of monitoring wear amount

Abstract

The application discloses a mechanical sealing device for monitoring wear amount, wherein a plurality of dynamic pressure grooves are uniformly distributed along the circumferential direction on the sealing end surface of the dynamic ring near the outer diameter, a plurality of first conductive layers are arranged on the sealing end surface of the dynamic ring, the plurality of first conductive layers are electrically connected to one another and are electrically connected to one pole of an external circuit; a plurality of concave structures are uniformly distributed along the circumferential direction on the sealing end surface of the static ring, the plurality of dynamic pressure grooves can pass through the plurality of concave structures when the dynamic ring rotates; a plurality of second conductive layers are arranged on the sealing end surface of the static ring, the plurality of second conductive layers are distributed on the concave bottom surfaces of the plurality of concave structures, one end of the parallel circuit of the plurality of second conductive layers is electrically connected to the other pole of the external circuit, and the parallel circuit of the plurality of second conductive layers is provided with a signal device; and a displacement monitor is further arranged on the static ring. The application can monitor the wear amount of the sealing end surface of the static ring under the contact or non-contact condition of the mechanical sealing end surface, has a wide application range, and can avoid safety hazards and economic losses.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wear amount monitoring of mechanical seal devices, and particularly to a mechanical seal device capable of monitoring wear amount. BACKGROUND

[0002] Mechanical seals are generally used as shaft end seals of rotating mechanical equipment, and can work at high parameters, and are widely used in the fields of petrochemical industry, nuclear energy, aerospace, etc.

[0003] Generally, due to good followability, the seal end face contact is controlled within a reasonable range, although the mechanical seal is usually designed to be not prone to wear, but the errors in design calculation, manufacturing and assembly, changes in working conditions, external impacts and other uncontrollable factors will cause the wear to deviate from the expected state, affect the normal working performance of the seal, and thus cause the end face contact friction and wear to be stronger. Mechanical end face contact friction and wear mainly occur on the static ring, which is an irreversible process, which will cause the normal leakage channel to be damaged, thereby increasing the leakage and shortening the service life of the seal. Therefore, it is particularly important to monitor the real-time wear amount of the seal end face, and the working personnel can understand the seal running state in real time according to the wear amount monitoring result, and replace the seal in time to avoid major accidents and economic losses. SUMMARY

[0004] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, one object of the present application is to provide a mechanical seal device capable of monitoring wear amount, which can intelligently monitor the wear amount of the seal end face of the static ring under the condition of mechanical seal end face contact or non-contact, has a wide range of applications, and avoids safety hazards and economic losses.

[0005] The mechanical seal device capable of monitoring wear amount according to the embodiment of the present application comprises a dynamic ring and a static ring arranged coaxially and end to end;

[0006] Among them, a plurality of dynamic pressure grooves are uniformly distributed along the circumferential direction on the seal end face of the dynamic ring close to the outer diameter, a plurality of first conductive layers are arranged on the seal end face of the dynamic ring, the plurality of first conductive layers are distributed at the interval positions between adjacent dynamic pressure grooves, and the plurality of first conductive layers are integrally connected to each other and electrically connected to one of the positive electrode and the negative electrode of an external circuit.

[0007] The sealing end face of the static ring is provided with a plurality of concave structures distributed uniformly in the circumferential direction, and when the dynamic ring rotates, a plurality of dynamic pressure grooves can pass through a plurality of the concave structures; the sealing end face of the static ring is provided with a plurality of second conductive layers, the plurality of second conductive layers are distributed on the concave bottom surfaces of the plurality of concave structures and correspond to the first conductive layers, one end of the parallel circuit of the plurality of second conductive layers is electrically connected to the other of the positive electrode and the negative electrode of the external circuit, and the parallel circuit of the plurality of second conductive layers is provided with a signal device; the static ring is further provided with a displacement monitor for monitoring the angular displacement disturbance of the static ring when the dynamic ring rotates at a high speed.

[0008] The mechanical sealing device capable of monitoring wear amount according to the embodiment of the application can realize online quantitative monitoring of wear amount under the condition of mechanical sealing end face contact or non-contact, realizes online step-by-step wear amount monitoring under the condition of contact, realizes online stepless wear amount monitoring under the condition of non-contact, and has a wide range of applications. Moreover, the mechanical sealing device capable of monitoring wear amount according to the embodiment of the application can monitor the sealing operation life by monitoring the sealing wear amount, and timely maintenance can avoid safety hazards and economic losses.

[0009] In some embodiments, the arrangement position of the concave structure on the sealing end face of the static ring corresponds to the radial outer end of the dynamic pressure groove, and the arrangement position of the first conductive layer is consistent with the radial outer end of the dynamic pressure groove.

[0010] In some embodiments, the arrangement position of the concave structure on the sealing end face of the static ring corresponds to the radial groove root of the dynamic pressure groove, and the arrangement position of the first conductive layer is consistent with the radial groove root of the dynamic pressure groove.

[0011] In some embodiments, the concave bottom surface of the concave structure is a layered surface including a plurality of layered surfaces with different depths, and each of the layered surfaces is provided with the second conductive layer.

[0012] In some embodiments, the first conductive layers are sequentially connected to form a ring-shaped conductive layer.

[0013] In some embodiments, the first conductive layer and the second conductive layer are obtained by an additive manufacturing method.

[0014] In some embodiments, the peripheral wall of the concave structure is a slope wall.

[0015] In some embodiments, the signal device is an indicator light or an alarm.

[0016] Additional aspects and advantages of the application will be set forth in part in the description that follows, and in part will become apparent to those skilled in the art upon examination of the following and / or can be learned by practice of the application. BRIEF DESCRIPTION OF DRAWINGS

[0017] The above and / or additional aspects and advantages of the present application will become apparent and more readily appreciated from the following description, taken in conjunction with the following drawings of which:

[0018] Figure 1 A schematic view of a partial section of a mechanical seal device with monitorable wear amount according to the present application;

[0019] Figure 2 A schematic view of a sealing face of a dynamic ring according to the present application;

[0020] Figure 3 A schematic view of a sealing face of a static ring according to the present application;

[0021] Figure 4 A schematic view of a partial section of a mechanical seal device with monitorable wear amount according to the present application; Figure 2 A schematic view of a partial section of a mechanical seal device with monitorable wear amount according to the present application;

[0022] Figure 5 A schematic view of a circuit of a mechanical seal device with monitorable wear amount according to an embodiment of the present application;

[0023] Figure 6 A schematic view of an angular displacement signal of a dynamic simulation model according to the present application;

[0024] Figure 7 A schematic view of a sealing face of a dynamic ring according to the present application;

[0025] Figure 8 A schematic view of a sealing face of a static ring according to the present application;

[0026] Figure 9 A schematic view of a sealing face of a static ring according to the present application;

[0027] Figure 10 A schematic view of a partial section of a mechanical seal device with monitorable wear amount according to the present application; Figure 9 A schematic view of a partial section of a mechanical seal device with monitorable wear amount according to the present application.

[0028] Reference Signs:

[0029] Mechanical seal device with monitorable wear amount 1000; dynamic ring 1; dynamic pressure groove 101; first electrically conductive layer 102; static ring 2; concave structure 201; ramp wall 2011; second electrically conductive layer 202; external circuit 3; signal device 4; displacement monitor 5. DETAILED DESCRIPTION

[0030] Embodiments of the present application are described below in detail with reference to the accompanying drawings, in which like or similar elements are denoted by the same or similar reference signs, and the embodiments described below are examples only for explaining the present application, and are not to be understood as limiting the present application.

[0031] The embodiments of the present application will be described below with reference to the accompanying drawings. Figures 1 to 10The mechanical seal device 1000 with monitorable wear amount according to the embodiment of the present application is described.

[0032] The mechanical seal device 1000 with monitorable wear amount according to the embodiment of the present application is a fluid seal device, such as a dry gas seal device.

[0033] As shown in Figures 1 to 10 , the mechanical seal device 1000 with monitorable wear amount according to the embodiment of the present application comprises a dynamic ring 1 and a static ring 2 coaxially arranged in an end-to-end manner, the dynamic ring 1 and the static ring 2 form a pair of mechanical seal rings, and the end faces of the dynamic ring 1 and the static ring 2 facing each other are sealing end faces. In the process of mechanical sealing, the dynamic ring 1 rotates, the static ring 2 does not rotate, and the friction pair between the dynamic ring 1 and the static ring 2 plays a role of mechanical sealing (i.e. rotary sealing). The static ring 2 has floating property, and the static ring 2 is designed to maintain a relatively stable relative motion relationship between the end face and the end face of the dynamic ring 1 under the action of various forces, so as to prevent the distance between the static ring 2 and the dynamic ring 1 from being too large to cause excessive leakage, or contact to be damaged quickly.

[0034] A plurality of dynamic pressure grooves 101 (see Figure 2 and Figure 7 ) are uniformly distributed in the circumferential direction near the outer diameter of the sealing end face of the dynamic ring 1. The dynamic pressure grooves 101 can be spiral grooves or grooves of other shapes as shown in Figure 2 . The dynamic pressure grooves 101 provide a certain stiffness for the dynamic ring 1 and the static ring 2 during rotary sealing. Specifically, when the dynamic ring 1 rotates to a high speed, the dynamic pressure grooves 101 generate a fluid dynamic pressure effect, so that a stable fluid film is formed between the dynamic ring 1 and the static ring 2, the fluid film separates the dynamic ring 1 and the static ring 2, at this time, the sealing end face of the dynamic ring 1 and the sealing end face of the static ring 2 maintain a relatively stable motion relationship, and the sealing end face of the dynamic ring 1 and the sealing end face of the static ring 2 do not occur solid contact.

[0035] Although the mechanical seal is designed to not occur solid contact friction during normal stable operation, due to uncontrollable factors such as errors in design calculation, errors in manufacturing and assembly, changes in working conditions, external impact, etc., the sealing end face of the dynamic ring 1 and the sealing end face of the static ring 2 still occur solid contact friction, and then cause sealing end face contact friction wear, which mainly occurs on the static ring 2. Therefore, it is necessary to monitor the wear condition of the sealing end face of the static ring 2 in real time online, so as to replace the static ring 2 in time.

[0036] In order to realize online real-time intelligent monitoring of the wear amount of the sealing end face of the static ring 2, referring to Figure 2 , Figure 5 and Figure 7The sealing end surface of the dynamic ring 1 is further provided with a plurality of first conductive layers 102, which are distributed at interval positions between adjacent dynamic pressure grooves 101 and are electrically connected to one of the positive and negative poles of the external circuit 3.

[0037] Referring to Figures 3 to 5 and Figures 8 to 10 The sealing end surface of the static ring 2 is provided with a plurality of concave structures 201 which are evenly distributed along the circumferential direction, and the plurality of dynamic pressure grooves 101 can pass through the plurality of concave structures 201 when the dynamic ring 1 rotates. The sealing end surface of the static ring 2 is further provided with a plurality of second conductive layers 202 which are distributed on the bottom surfaces of the plurality of concave structures 201 and correspond to the first conductive layers 102. One end of the parallel circuit of the plurality of second conductive layers 202 is electrically connected to the other of the positive and negative poles of the external circuit 3, and the parallel circuit of the plurality of second conductive layers 202 is further provided with a signal device 4. The static ring 2 is further provided with a displacement monitor 5 for monitoring the angular displacement disturbance of the static ring 2 when the dynamic ring 1 rotates at a high speed.

[0038] When the dynamic ring 1 rotates at a low speed, the sealing end surfaces of the dynamic ring 1 and the static ring 2 do not form a stable fluid film, and the sealing end surfaces of the dynamic ring 1 and the static ring 2 are in solid contact. When the sealing end surface of the static ring 2 is in the initial stage of wear (i.e., the wear amount of the sealing end surface of the static ring 2 is small), none of the second conductive layers 202 contacts the first conductive layers 102, the external circuit 3 is not conductive, and the signal device 4 on the parallel circuit of the corresponding second conductive layer 202 does not emit a signal. When the wear amount of the sealing end surface of the static ring 2 is greater than or equal to the depth of the concave structure 201 (i.e., the wear amount of the sealing end surface of the static ring 2 is large), if the sealing end surface of the static ring 2 is uniformly worn, all of the second conductive layers 202 contact the first conductive layers 102, the external circuit 3 is conductive, and the signal device 4 on the parallel circuit of all of the second conductive layers 202 emits a signal. If the sealing end surface of the static ring 2 is not uniformly worn, the degrees of wear of different concave structures 201 are inconsistent, and the second conductive layers 202 in some concave structures 201 contact the first conductive layers 102, and the signal device 4 on the parallel circuit of the second conductive layers 202 that contact the first conductive layers 102 emits a signal, i.e., part of the signal indicating devices emits a signal. That is, when the dynamic ring 1 rotates at a low speed, the wear amount of the sealing end surface of the static ring 2 is monitored by whether the second conductive layers 202 contact the first conductive layers 102, and the wear amount of the sealing end surface of the static ring 2 is monitored on-line in stages.

[0039] When the rotating ring 1 rotates at high speed, the dynamic pressure groove 101 generates a fluid dynamic pressure effect, so that a stable fluid film is formed between the rotating ring 1 and the static ring 2, the fluid film separates the rotating ring 1 and the static ring 2, at this time, the sealing end face of the rotating ring 1 and the sealing end face of the static ring 2 do not have solid contact, because high pressure areas are generated in the dynamic pressure groove 101 of the rotating ring 1, these local high pressure areas will meet the concave structure 201 on the static ring 2 constantly with the rotation of the rotating ring 1, each time the dynamic pressure groove 101 of the rotating ring 1 meets the concave structure 201, the pressure in the dynamic pressure groove 101 will be released due to the sudden increase in space, thereby causing the pressure of the fluid film of the sealing end face to suddenly change, which causes the angular displacement disturbance of the static ring 2, and the angular displacement disturbance of the static ring 2 is monitored by the displacement monitor 5. Specifically, if there are n concave structures 201 on the surface of the static ring 2, then the high pressure area in the dynamic pressure groove 101 on the ring ring will have n times of pressure release in one rotation period, thereby generating an n times frequency signal in the displacement signal frequency domain of the displacement monitor 5, if there are m dynamic pressure grooves 101, then at most m x n times of pressure disturbance will be generated. As the wear amount of the sealing end face of the static ring 2 gradually increases, the monitoring structure of the sealing end face of the static ring 2 is gradually worn out until it is worn out, in this process, the space volume of the concave structure 201 will gradually decrease, the disturbance will gradually decrease and weaken, and the disturbance signal monitored by the displacement monitor 5 will also gradually weaken; when the wear monitoring structure is worn out, the disturbance signal from the displacement monitor 5 will disappear. Therefore, an alarm threshold can be set, when the wear amount reaches a certain degree, the disturbance signal amount will be lower than the threshold, thereby triggering the alarm. That is to say, when the rotating ring 1 rotates at high speed, under the condition that the second conductive layer 202 does not contact the first conductive layer 102, the angular displacement disturbance of the static ring 2 is monitored by the displacement monitor 5 to realize the stepless monitoring of the wear amount of the sealing end face of the static ring 2.

[0040] As shown in Figure 2 , seven concave structures 201 are manufactured on the static ring 2, the angular displacement of the static ring 2 is simulated by using a dynamic simulation model, and the result is shown in Figure 6 , Figure 6 , the angular displacement of the static ring 2 is schematically shown, it can be found in the frequency domain diagram on the right side that the angular displacement of the static ring 2 appears 7 times frequency, which verifies the effectiveness of the technical scheme of the present application, and it is proved that the angular displacement signal of the static ring 2 can be monitored by the displacement monitor 5, and the corresponding characteristics can be found in the frequency domain of the signal.

[0041] The mechanical seal device 1000 capable of monitoring wear amount according to the embodiment of the present application can realize online quantitative monitoring of wear amount under the condition of mechanical seal end face contact or non-contact, realizes online stepwise end face wear amount monitoring under the condition of contact, realizes online stepless wear amount monitoring under the condition of non-contact, and is widely applicable. Moreover, the mechanical seal device 1000 capable of monitoring wear amount according to the embodiment of the present application can monitor the sealing operation life by monitoring the sealing wear amount, and timely maintenance can avoid safety hazards and economic losses.

[0042] In some embodiments, such as Figures 2 to 4 As shown, the concave structure 201 is positioned on the sealing end face of the stationary ring 2, corresponding to the radial outer end of the dynamic pressure groove 101, and the first conductive layer 102 is positioned on the same radial outer end as the dynamic pressure groove 101. It is understandable that placing the concave structure 201 on the sealing end face of the stationary ring 2 will essentially cause fluid film pressure instability, making it more difficult to open the sealing end face between the rotating ring 1 and the stationary ring 2. However, when the concave structure 201 is positioned on the sealing end face of the stationary ring 2, corresponding to the radial outer end of the dynamic pressure groove 101 (i.e., when the concave structure 201 is located at the outer edge of the sealing end face of the stationary ring 2), the hydrostatic pressure effect within the concave structure 201 will make it easier to open the sealing end face between the rotating ring 1 and the stationary ring 2.

[0043] In some embodiments, such as Figures 7 to 8 As shown, the concave structure 201 is positioned on the sealing end face of the stationary ring 2, corresponding to the radial root of the dynamic pressure groove 101; the first conductive layer 102 is positioned at the same location as the radial root of the dynamic pressure groove 101. Since the gas film pressure of the dynamic pressure groove 101 is mainly concentrated at the root of the groove, placing the concave structure 201 at the position of the stationary ring 2 corresponding to the root of the dynamic pressure groove 101 allows the stationary ring 2 to generate more obvious angular displacement disturbances, making it easier for the displacement monitor 5 to detect the angular displacement disturbance signal and facilitate accurate judgment.

[0044] In some embodiments, the concave bottom surface of the concave structure 201 comprises multiple layered surfaces of different depths, each layered surface having a second conductive layer 202. Taking a double-layered surface as an example... Figures 9 to 10 As shown, the total depth of the concave structure 201 is α, the depth of the first layer surface is α-β, and the depth of the second layer surface is β.

[0045] like Figure 6 As shown, when the wear of the sealing end face of the stationary ring 2 is less than α-β and the rotation speed of the moving ring 1 is low, the first conductive layer 102 will not contact the second conductive layer 202, and the signal device 4 on all the parallel lines of the second conductive layer 202 will not send a signal. When the rotation speed of the moving ring 1 is high, the 7th and 14th harmonic components appear in the frequency domain of the disturbance signal of the displacement monitor 5.

[0046] When the wear of the sealing end face of the stationary ring 2 is equal to α-β and the rotation speed of the moving ring 1 is low, the first conductive layer 102 and the second conductive layer 202 on all the first layer surfaces come into contact. The signal device 4 on the parallel line of the second conductive layer 202 on the first layer surface in contact with the first conductive layer 102 sends a signal. When the rotation speed of the moving ring 1 is high, the 14th harmonic component appears in the frequency domain of the disturbance signal of the displacement monitor 5, and the 7th harmonic component weakens to the point of being indistinguishable.

[0047] When the wear amount of the sealing end surface of the static ring 2 is greater than a-β and less than β, if the rotating speed of the dynamic ring 1 is low, the first conductive layer 102 does not contact the second conductive layer 202 on the second layered surface, and the signal device 4 on the parallel circuit of all the second conductive layers 202 does not send out a signal. When the rotating speed of the dynamic ring 1 is high, a 14th harmonic component appears in the frequency domain of the disturbance signal of the displacement monitor 5, and a 7th harmonic component cannot be identified.

[0048] When the wear amount of the sealing end surface of the static ring 2 is equal to β, if the rotating speed of the dynamic ring 1 is low, the first conductive layer 102 contacts the second conductive layer 202 on the second layered surface, and the signal device 4 on the parallel circuit of all the second conductive layers 202 contacting the first conductive layer 102 sends out a signal. When the rotating speed of the dynamic ring 1 is high, the 14th harmonic component in the frequency domain of the disturbance signal of the displacement monitor 5 weakens to be unidentifiable.

[0049] In some embodiments, the plurality of first conductive layers 102 are sequentially connected to form a ring-shaped conductive layer, so that the plurality of first conductive layers 102 are electrically connected in one body, facilitating the connection with the electrodes of the external circuit 3.

[0050] In some embodiments, the first conductive layer 102 and the second conductive layer 202 are both obtained by an additive manufacturing method. Specifically, the first conductive layer 102 and the second conductive layer 202 can be obtained by spraying, electroplating, or coating.

[0051] In some embodiments, as shown in Figs. 1 and 2, the plurality of first conductive layers 102 are sequentially connected to form a ring-shaped conductive layer, so that the plurality of first conductive layers 102 are electrically connected in one body, facilitating the connection with the electrodes of the external circuit 3. Figure 4 and Figure 10 In some embodiments, as shown in Figs. 1 and 2, the peripheral wall of the concave structure 201 is a slope wall 2011, which can make the central angle of the concave structure 201 decrease as the wear aggravates, thereby causing the pressure release effect of the high-pressure area inside the dynamic pressure groove 101 to weaken, and facilitating the gradual weakening of the disturbance signal monitored by the displacement monitor 5.

[0052] In some embodiments, the signal device 4 is an indicator light or an alarm, which can be selected as needed.

[0053] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "exemplary embodiment", "example", "specific example", or "some examples" means that the specific features, structures, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the exemplary description of the above terms does not necessarily mean the same embodiment or example. Moreover, the specific features, structures, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0054] While embodiments of the application have been shown and described, it is to be understood that the embodiments described are merely divergences of the principles and application of the present application and that numerous modifications, changes, substitutions, and alterations can be made thereto without departing from the spirit and scope of the present application, which is defined by the following claims and their equivalents.

Claims

1. A mechanical seal device capable of monitoring wear amount, comprising a dynamic ring and a static ring arranged coaxially and end to end; wherein a plurality of dynamic pressure grooves are evenly distributed in circumferential direction on the sealing end face of the dynamic ring near the outer diameter, a plurality of first conductive layers are arranged on the sealing end face of the dynamic ring, the plurality of first conductive layers are distributed at the interval positions between adjacent dynamic pressure grooves, and the plurality of first conductive layers are electrically connected to one of the positive electrode and the negative electrode of an external circuit; a plurality of recess structures are evenly distributed in circumferential direction on the sealing end face of the static ring, and the plurality of dynamic pressure grooves can pass through the plurality of recess structures when the dynamic ring rotates; a plurality of second conductive layers are arranged on the bottom surface of the plurality of recess structures and correspond to the first conductive layers, one end of the parallel circuit of the plurality of second conductive layers is electrically connected to the other of the positive electrode and the negative electrode of the external circuit, and a signal device is arranged on the parallel circuit of the plurality of second conductive layers; a displacement monitor is further arranged on the static ring to monitor the angular displacement disturbance of the static ring when the dynamic ring rotates at high speed.

2. The mechanical seal device with a monitorable amount of wear according to claim 1, wherein, The arrangement position of the recess structure on the sealing end face of the static ring corresponds to the radial outer end of the dynamic pressure groove, and the arrangement position of the first conductive layer corresponds to the radial outer end of the dynamic pressure groove.

3. The mechanical seal device with a monitorable amount of wear according to claim 1, wherein, The arrangement position of the recess structure on the sealing end face of the static ring corresponds to the radial groove root of the dynamic pressure groove, and the arrangement position of the first conductive layer corresponds to the radial groove root of the dynamic pressure groove.

4. The mechanical seal device with a monitorable amount of wear according to claim 1, wherein, The bottom surface of the recess structure comprises a plurality of layered surfaces with different depths, and the second conductive layer is arranged on each layered surface.

5. The mechanical seal device with a monitorable wear amount according to any one of claims 1 to 4, characterized by, The plurality of first conductive layers are sequentially connected to form a ring-shaped conductive layer.

6. The mechanical seal device with a monitorable wear amount according to any one of claims 1 to 4, characterized by, The first conductive layer and the second conductive layer are obtained by an additive manufacturing method.

7. The mechanical seal device with a monitorable wear amount according to any one of claims 1 to 4, characterized by The peripheral wall of the recess structure is a slope wall.

8. The mechanical seal device with a monitorable wear amount according to any one of claims 1 to 4, characterized by, The signal device is an indicator light or an alarm.

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