Rotary joint with clearance active compensation and self-adaptive adjustment functions and control method

Abstract

According to the clearance active compensation and self-adaptive adjustment rotary joint and the control method, by means of a double active compensation structure formed by the circumferential spring and the sealing ring body and a double active compensation structure formed by the axial spring and the integral sealing ring, the abrasion clearance can be filled in time, and the stable sealing specific pressure can be continuously maintained. Meanwhile, cooperative linkage with a multi-parameter leakage detection self-adaptive system is achieved, an intelligent sealing guarantee system is constructed, and the capacity of dealing with abrasion and leakage problems is remarkably improved; by means of the multi-sealing layout and the continuous compensation function, the system can actively recover the sealing performance in the non-stop state, and therefore the service life of a sealing assembly and the equipment maintenance period are greatly prolonged. By adopting a multi-signal fusion monitoring strategy of differential pressure, flow, liquid level, torque, pre-tightening force and the like, the limitation of single sensing is effectively overcome, the accuracy of leakage diagnosis and the early warning capability are greatly improved, and the system is particularly suitable for high-temperature and high-pressure harsh operation working conditions.

Description

TECHNICAL FIELD

[0001] The application relates to the field of rotary joints, in particular to a rotary joint with active compensation of a gap and adaptive adjustment and a control method. BACKGROUND

[0002] Under the background of rapid development of solar thermal power generation technology, molten salt has become the core heat transfer medium of the trough type photothermal system due to the characteristics of high operating temperature (up to more than 560 DEG C), high working pressure (up to more than 6 MPa) and excellent thermal stability; the system has clear requirements for the rotary joint, which needs to realize reliable sealing between the rotating heat collecting pipe and the fixed pipe under high temperature and high pressure conditions, and guarantee the stability of long-term reliable operation of the equipment.

[0003] The current widely used rotary joint still has significant shortcomings: first, the sealing surface is easy to wear due to continuous rotation and friction, and then the leakage gap is expanded; second, the sealing material is easy to age and deform in a high temperature environment, directly leading to attenuation of sealing performance; third, the existing structure lacks an effective online wear compensation mechanism, which seriously restricts the continuous and stable operation of the system.

[0004] In summary, under the working condition of high temperature and high pressure, how to improve the sealing reliability and service life of the rotary joint sealing has become a problem that researchers in the field urgently need to solve. SUMMARY

[0005] The technical problem to be solved by the application is how to improve the sealing reliability and service life of the rotary joint sealing under the working condition of high temperature and high pressure. To solve the above technical problems, the technical scheme adopted by the application is as follows: The application is a rotary joint with active compensation of a gap and adaptive adjustment, comprising: a rotary joint assembly and an adaptive leakage detection system. The rotary joint assembly comprises: an outer shell, an inner pipe coaxially arranged with the outer shell, a gland arranged outside the inner pipe, and the gland inserted into the gap between the outer shell and the inner pipe, wherein a sealing assembly is arranged between the outer shell and the inner pipe and between the end of the gland and the outer shell; the ends of the outer shell and the gland are provided with connecting flanges, and the two connecting flanges are connected through a locking assembly. The adaptive leakage detection system comprises: a flow meter for monitoring the flow in the outer shell and the inner pipe; a pressure gauge for monitoring the pressure in the outer shell and the inner pipe; a force sensor for detecting the change of the locking force of the locking assembly; a leakage collector for collecting leakage between the outer shell and the inner pipe; a video monitor for acquiring pictures of the inlet side and the outlet side of the rotary joint; a thermal imager for acquiring the temperature of the inlet side and the outlet side of the rotary joint; and a multi-axis tightening machine for controlling the tightening of the locking assembly.

[0006] Further, the sealing assembly comprises: a split graphite sealing ring arranged in the sealing groove of the inner tube end, a sealing ring body in the split graphite sealing ring is located in the sealing groove, and the sealing ring body is sleeved with the circumferential spring, and the circumferential spring presses the sealing ring body against the outer wall of the inner tube.

[0007] Further, the inner tube end is provided with a ring body, and the sealing groove is formed between the two ring bodies. The one ring body away from the inner tube end and the gland end are sequentially and axially provided with a whole sealing ring, a gasket and an axial spring.

[0008] Further, the self-adaptive leakage detection system further comprises a torque sensor for acquiring a rotating torque change signal of the rotary joint.

[0009] Further, the self-adaptive leakage detection system further comprises a signal processor and a signal collector, the signal processor and the signal collector are communicatively connected, the signal collector receives image signals, temperature signals, pressure difference signals, flow difference signals, leakage liquid level signals, rotary joint torque signals and force signals of the locking assembly, and outputs a leakage judgment result after analysis by the signal processor.

[0010] 6. The gap active compensation and self-adaptive adjustment rotary joint according to claim 5, characterized in that the multi-axis tightening machine is used to tighten the locking assembly, adjust the distance between the connecting flange of the outer shell and the connecting flange of the gland, and actively seal between the outer shell and the inner tube.

[0011] Further, the locking assembly comprises a bolt and a nut, the bolt passes through the connecting flange and is connected with the nut, wherein the multi-axis tightening machine acts on the head of the bolt, and the force sensor is used to detect the change of the pre-tightening force of the bolt.

[0012] The application also discloses a control method of the rotary joint, comprising the following steps: When any of the following conditions is detected, the multi-axis tightening machine automatically tightens the bolt: A: the signal collector receives image signals of video monitoring and temperature signals of the thermal imager and sends them to the signal processor for analysis; the high-definition camera combined with the deep learning algorithm automatically identifies liquid leakage in the pipeline or the surrounding area, the signal processor sends a tightening instruction of the multi-axis tightening machine; at the same time, the infrared thermal imager rechecks to prevent the pipeline surface from being contaminated or having a very small leakage point which is not conducive to identification; combined with the feedback of the thermal imaging information, the signal processor sends a tightening instruction, and the multi-axis tightening machine automatically tightens the bolt.

[0013] B: When the signal processor monitors that the difference between P1 and P2 obtained by the pressure gauge suddenly changes, and monitors that q1≠q2 obtained by the flow meter, the signal processor issues a tightening instruction, and the bolt multi-axis tightening machine automatically tightens the bolt; wherein P1 is the pressure in the shell, P2 is the pressure in the inner tube, q1 is the medium flow in the shell, and q2 is the medium flow in the inner tube.

[0014] C: When the signal processor monitors that the bolt pre-tightening force F obtained by the force sensor is less than the set value, the signal processor issues a tightening instruction, and the bolt multi-axis tightening machine automatically tightens the bolt.

[0015] D: When the signal processor monitors that the rotation torque T obtained by the torque sensor is less than the set value, the signal processor issues a tightening instruction, and the bolt multi-axis tightening machine automatically tightens the bolt.

[0016] The beneficial effects of the present application: With the help of the double active compensation structure composed of the circumferential spring and the sealing ring body, the axial spring and the integral sealing ring, the wear gap can be filled in time, and the stable sealing specific pressure can be maintained. At the same time, the intelligent sealing guarantee system is constructed in cooperation with the multi-parameter leakage detection adaptive system, and the response ability to wear and leakage problems is significantly improved; relying on the above multiple sealing layout and continuous compensation function, the system can actively restore the sealing performance under the condition of not stopping, and then greatly prolong the service life and equipment maintenance period of the sealing assembly.

[0017] In addition, by adopting the multi-signal fusion monitoring strategy of pressure difference, flow, liquid level, torque and pre-tightening force, the limitation of single sensing is effectively overcome, the accuracy and early warning ability of leakage diagnosis are greatly improved, and it is especially suitable for harsh operating conditions of high temperature and high pressure. BRIEF DESCRIPTION OF DRAWINGS

[0018] The present application will be further described below in conjunction with the drawings and examples.

[0019] Fig. 1 is a structural schematic diagram of the present embodiment; Fig. 2 is a sectional view of the present embodiment. DETAILED DESCRIPTION

[0020] The present application will be further described below in conjunction with the drawings and examples.

[0021] Referring to Figs. 1-2 , the present embodiment is a gap active compensation and adaptive adjustment rotary joint, comprising: a rotary joint assembly, an adaptive leakage detection system; The rotary joint assembly comprises: a shell 1, an inner tube 2 coaxially arranged in the shell 1, a gland 3 arranged on the outer tube 2, the gland 3 inserted into the gap between the shell 1 and the inner tube 2, wherein a sealing assembly is arranged between the shell 1 and the inner tube 2 and between the end of the gland 3 and the shell 1; the end of the shell 1 and the gland 3 is provided with a connecting flange 4, and the two connecting flanges 4 are connected by a locking assembly 5; In the embodiment, the inner tube 2 is coaxially arranged on the right side of the shell 1, the left end of the inner tube 2 is located in the shell 1, the outer tube 2 is arranged on the outer tube 2, and the shell 1 and the gland 3 are connected by the two connecting flanges 4 and the locking assembly 5. The sealing assembly is arranged in the space formed by the end of the gland 3, the inner tube 2 and the shell 1. The sealing assembly can be self-adaptively adjusted to ensure the sealing performance between the shell 1, the inner tube 2 and the gland 3, and to avoid leakage of the medium.

[0022] Of course, after the sealing assembly fails to realize the sealing of the rotary joint, an active compensation method is adopted to ensure the sealing performance of the rotary structure. Specifically, an adaptive leakage detection system is adopted, which comprises: a flow meter 01 for monitoring the flow in the shell 1 and the inner tube 2; a pressure gauge 02 for monitoring the pressure in the shell 1 and the inner tube 2; a force sensor 05 for detecting the change of locking force of the locking assembly 5; a leakage collector 03 for collecting leakage between the shell 1 and the inner tube 2; a video monitoring device for obtaining pictures of the inlet side and the outlet side of the rotary joint; a thermal imager for obtaining the temperature of the inlet side and the outlet side of the rotary joint; a multi-axis tightening machine 04 for controlling the tightening of the locking assembly 5; In the embodiment, the state change of the rotary joint is monitored by the flow meter 01, the pressure gauge 02 and the force sensor 05. After the state change, the locking assembly 5 is tightened by the multi-axis tightening machine 04, so that the gland 3 is close to the shell 1, the sealing assembly is compressed twice, and the sealing performance of the rotary joint is ensured. The thermal imager and the video monitoring device are used to detect whether the rotary joint leaks after the sealing assembly is compressed twice. In other words, the high-definition video monitoring device is used to obtain the images of the inlet side and the outlet side of the rotary joint assembly, the infrared thermal imager is used to obtain the temperature of the inlet side and the outlet side of the rotary joint assembly, the pressure gauge 02 is used to obtain the pressure difference signal between the inlet side and the outlet side of the rotary joint, the ultrasonic flow meter 01 is used to obtain the flow difference signal between the inlet side and the outlet side, the force sensor 05 is used to obtain the pre-tightening force change signal of the bolt 51 in the locking assembly 5 at the gland, the torque sensor is used to obtain the rotary torque change signal of the rotary joint, and the leakage collector is used to collect the leakage material and obtain the liquid level signal of the leakage material. The bolt 51 is automatically tightened by the multi-axis tightening machine 04 to restore the sealing and inhibit the leakage.

[0023] In some possible embodiments, the sealing assembly comprises: a split graphite sealing ring 6 arranged in the sealing groove at the end of the inner tube 2, a sealing ring body 61 in the split graphite sealing ring 6 is located in the sealing groove, and the sealing ring body 61 is sleeved with the circumferential spring 62, and the circumferential spring 62 presses the sealing ring body 61 against the outer wall of the inner tube 2; In the embodiment, the split graphite sealing ring 6 is used to provide circumferential sealing between the outer shell 1 and the inner tube 2. Specifically, the sealing ring body 61 is composed of a plurality of arc-shaped sealing segments, and the outer diameter surface of the sealing ring body 61 is provided with a ring groove, and the circumferential spring 62 is located at the ring groove. The circumferential spring 62 is a compression spring, which presses the sealing ring body 61 against the outer wall of the inner tube 2. During long-term use of the sealing joint, the circumferential spring 62 and the sealing ring body 61 perform circumferential compensation between the inner tube 2 and the outer shell 1.

[0024] In some possible embodiments, the end of the inner tube 2 protrudes to be provided with a ring body, and the sealing groove is formed between the two ring bodies. The integral sealing ring 63, the gasket 64 and the axial spring 65 are sequentially and axially arranged between one of the ring bodies away from the end of the inner tube 2 and the end of the gland 3. In the embodiment, the integral sealing ring 63, the gasket 64 and the axial spring 65 are arranged between the end of the gland 3 and the ring body. During long-term use of the sealing joint, when the integral sealing ring 63 is worn, the axial spring 65 performs compensation, that is, the integral sealing ring 63 is self-propelled and compressed by the axial spring 65, so that the integral sealing ring 63 is always axially sealed between the outer shell 1 and the inner tube 2.

[0025] In some possible embodiments, the self-adaptive leakage detection system further comprises a torque sensor for acquiring a rotating torque change signal of the rotary joint. In the embodiment, the torque sensor is used to detect the torque change of the inner tube in the rotary joint. Once the torque of the inner tube decreases, there is a risk of leakage, and at this time, the bolt is automatically tightened by the bolt multi-axis tightening machine 04.

[0026] In some possible embodiments, the self-adaptive leakage detection system further comprises a signal processor 05 and a signal collector 06, which are communicatively connected, and the signal collector 06 receives image signals, temperature signals, pressure difference signals, flow difference signals, leakage substance liquid level signals, rotary joint torque signals and force signals of the locking assembly 5, and outputs a leakage judgment result after analysis by the signal processor 06; In the embodiment, the signal collector 05 is used to collect image signals, temperature signals, differential pressure signals, flow difference signals, leakage liquid level signals, rotary joint torque signals and force signals of the locking assembly 5, and then feed back to the signal processor 06, and the signal processor 06 controls the bolt multi-axis tightening machine 04 to automatically tighten the bolt 51, so as to ensure the sealing performance of the rotary joint.

[0027] In some possible embodiments, the multi-axis tightening machine 04 is used to tighten the locking assembly 5, adjust the distance between the connecting flange 4 of the outer shell 1 and the connecting flange 4 of the gland 3, and actively seal between the outer shell 1 and the inner pipe 2. In the embodiment, when the split graphite sealing ring 6 and the integral sealing ring 63 fail to seal, the multi-axis tightening machine 7 is used to tighten the locking assembly 5 and actively seal the rotary joint.

[0028] In some possible embodiments, the locking assembly 5 comprises a bolt 51 and a nut 52, the bolt 51 passes through the connecting flange 4 and is connected with the nut 52, wherein the multi-axis tightening machine 04 acts on the head of the bolt 51, and the force sensor 05 is used to detect the change of the pre-tightening force at the bolt 51. In the embodiment, the multi-axis tightening machine 04 acts on the head of the bolt 51, and the distance between the outer shell 1 and the gland 2 is adjusted by rotating the bolt 51, so as to ensure the sealing performance of the rotary joint; the force sensor 05 also acts on the bolt 51, and the pre-tightening force data between the bolt 51 and the nut 52 can be obtained, so that the subsequent loosening of the bolt 51 and the nut 52 is avoided to prevent the leakage of the medium.

[0029] The application further discloses a control method of the rotary joint, A: the signal collector receives the image signals of the video monitoring and the temperature signals of the thermal imager and sends them to the signal processor 06 for analysis; the high-definition camera combined with the deep learning algorithm automatically identifies the liquid leakage of the pipeline or the periphery, the signal processor issues the tightening instruction of the multi-axis tightening machine 04, and at the same time, the infrared thermal imager rechecks to prevent the pipeline surface from being contaminated or the leakage point being too small to be identified; the signal processor issues the tightening instruction combined with the feedback of the thermal imaging information, and the bolt multi-axis tightening machine 04 automatically tightens the bolt 51.

[0030] B: the signal collector 05 sends the received pressure signals and flow signals to the signal processor for analysis; when the difference between P1 and P2 obtained by the pressure gauge 02 suddenly changes and q1≠q2 obtained by the flowmeter 01 is monitored, the signal processor 06 issues the tightening instruction, and the bolt multi-axis tightening machine 04 automatically tightens the bolt; wherein P1 is the pressure in the outer shell 1, P2 is the pressure in the inner pipe 2, q1 is the medium flow in the outer shell 1, and q2 is the medium flow in the inner pipe 2.

[0031] C: the signal collector 05 sends the received force change signal to the signal processor 06 for analysis; when the bolt 51 pre-tightening force F obtained by the force sensor 05 is less than the set value, the signal processor 06 issues a tightening instruction, and the bolt 51 multi-axis tightening machine 04 automatically tightens the bolt 51.

[0032] D: the signal collector 05 sends the received torque change signal to the signal processor 06 for analysis; when the rotation torque T obtained by the torque sensor is less than the set value, the signal processor 06 issues a tightening instruction, and the bolt multi-axis tightening machine 04 automatically tightens the bolt 51.

[0033] Working principle: when the inner tube 2 rotates, the split graphite sealing ring 6 of the first level sealing structure wears to increase the radial gap, and the circumferential spring 62 shrinks to make the sealing ring body 61 always adhere to the inner tube, actively compensating the radial gap and thereby inhibiting leakage; when the axial gap is generated by the end face wear of the integral sealing ring 63 of the second level sealing structure, the axial spring 65 pushes the integral sealing ring 63 to the left, actively compensating the axial gap; after long-term operation, the elastic elements of the two-layer sealing structure produce permanent deformation due to fatigue accumulation, and cannot actively compensate again.

[0034] At this time, the adaptive leakage detection system detects the leakage signal, the signal collector collects the above signals (such as flow change, bolt pre-tightening force change, etc.), and the signal processor 06 controls the driving multi-axis tightening machine 04 to automatically tighten the bolt according to the set program, again compresses the axial spring 65, restores the sealing and inhibits the leakage, and the bolt 51 multi-axis tightening machine 04 can also perform tightening angle monitoring and track and collect tightening data.

[0035] Based on the above ideal embodiments according to the present application, through the above description, relevant personnel can make various changes and modifications without deviating from the technical idea of the present application. The technical scope of the present application is not limited to the contents of the specification, and the technical scope must be determined according to the scope of claims.

Claims

1. A rotary joint with active compensation of the gap and adaptive adjustment, characterized in that, Comprise: Rotary joint assembly, adaptive leakage detection system; The rotary joint assembly comprises: a shell, an inner tube coaxially arranged with the shell, a gland sleeve arranged outside the inner tube, the gland sleeve is inserted into the gap between the shell and the inner tube, wherein a sealing assembly is arranged between the shell and the inner tube and between the end of the gland sleeve and the shell; The end of the shell and the gland sleeve is provided with a connecting flange, and the two connecting flanges are connected by a locking assembly; The adaptive leakage detection system comprises: a flow meter for monitoring the flow in the shell and the inner tube; A pressure gauge for monitoring the pressure in the shell and the inner tube; Force sensor for detecting the change of locking force of the locking assembly; A leakage collector for collecting leakage between the shell and the inner tube; Video monitoring for obtaining pictures of the inlet side and the outlet side of the rotary joint; The thermal imager is used for acquiring the temperature of the inlet side and the outlet side of the rotary joint; A multi-axis tightening machine for controlling the tightening of the locking assembly.

2. The gap-active-compensated and self-adjusting rotary joint according to claim 1, wherein, The sealing assembly comprises: a split graphite sealing ring arranged in a sealing groove opened at the end of the inner tube, a sealing ring body in the split graphite sealing ring is located in the sealing groove, and a circumferential spring is arranged outside the sealing ring body, and the circumferential spring presses the sealing ring body against the outer wall of the inner tube.

3. The gap-active-compensated and self-adjusting rotary joint according to claim 2, wherein, The end of the inner tube is provided with a ring body, and the sealing groove is formed between the two ring bodies. The end of the inner tube is provided with a ring body, and the sealing groove is formed between the two ring bodies.

4. The gap proactive compensation and adaptive adjustment rotary joint according to claim 1, characterized in that, The adaptive leakage detection system further comprises: a torque sensor for acquiring the change signal of the rotary torque of the rotary joint.

5. The gap-active-compensated and self-adjusting rotary joint according to claim 4, characterized in that, Also include: Signal processor, signal collector, the signal processor and the signal collector are communicatively connected, the signal collector receives image signals, temperature signals, pressure difference signals, flow difference signals, leakage liquid level signals, rotary joint torque signals and locking assembly force signals, and outputs leakage judgment results after analysis by the signal processor.

6. The gap-active-compensated and self-adjusting rotary joint according to claim 5, wherein, The multi-axis tightening machine is used for tightening the locking assembly, adjusting the distance between the connecting flange of the shell and the connecting flange of the gland, and actively sealing between the shell and the inner tube.

7. The gap-active-compensated and self-adjusting rotary joint according to claim 6, wherein, The locking assembly comprises a bolt and a nut, the bolt passes through the connecting flange and connects with the nut, wherein the multi-axis tightening machine acts on the head of the bolt, and the force sensor is used to detect the change of the pre-tightening force of the bolt.

8. A control method of a rotary joint, comprising the gap active compensation and adaptive adjustment of the rotary joint according to any one of claims 1-7, characterized in that, Comprise the following steps: When detecting any of the following conditions, the multi-axis tightening machine automatically tightens the bolt: A: The signal collector receives the image signal of the video monitoring and the temperature signal of the thermal imager and sends it to the signal processor for analysis; Combined with the high-definition camera of deep learning algorithm, liquid leakage in the pipeline or surrounding area is automatically identified, the signal processor sends the tightening instruction of the multi-axis tightening machine; At the same time, the infrared thermal imager will be rechecked to prevent the pipeline surface from being contaminated or the leakage point being too small to be identified; Combined with the feedback of thermal imaging information, the signal processor sends the tightening instruction, and the multi-axis tightening machine automatically tightens the bolt. B: When the signal processor monitors that the difference between P1 and P2 obtained by the pressure gauge changes suddenly, and monitors that q1≠q2 obtained by the flow meter, the signal processor sends a tightening instruction, and the bolt multi-axis tightening machine automatically tightens the bolt; wherein, P1 is the pressure in the shell, P2 is the pressure in the inner tube, q1 is the medium flow in the shell, and q2 is the medium flow in the inner tube. C: When the signal processor monitors that the bolt pre-tightening force F obtained by the force sensor is less than the set value, the signal processor sends a tightening instruction, and the bolt multi-axis tightening machine automatically tightens the bolt. D: When the signal processor monitors that the rotating torque T obtained by the torque sensor is less than the set value, the signal processor sends a tightening instruction, and the bolt multi-axis tightening machine automatically tightens the bolt.

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