Gas lubricated slip ring seal assembly
By introducing a flow diode and a headless screw design into the slip ring seal assembly, the problem of the seal gap opening during startup of the slip ring seal assembly is solved, achieving reliable sealing under all operating conditions and reducing maintenance costs.
Patent Information
- Application Number
- CN202480028750.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-07-27
- Filing Date
- 2024-05-27
- Publication Date
- 2025-11-25
AI Technical Summary
Existing slip ring sealing assemblies are prone to opening of the sealing gap during compressor startup, leading to leakage of the gas to be sealed. This fails to effectively prevent gas backflow and affects the normal startup and operation of the compressor.
The slip ring seal assembly employs a flow diode. The flow diode has low flow resistance in the preferred direction, ensuring that the fluid is blocked from being supplied to the slip ring seal, while the flow resistance in the opposite direction is greater to prevent backflow. Combined with the headless screw design, it is easy to install and modify.
It achieves the goal of maintaining a tight seal during compressor startup, preventing gas leakage, ensuring reliable compressor operation, and reducing maintenance costs and complexity.
Smart Images
Figure CN121013953A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a gas-lubricated slip ring seal assembly that exhibits excellent sealing characteristics under all operating conditions of a compressor or gas compressor. Background Technology
[0002] Slip ring seal assemblies are known from various existing design schemes. In these assemblies, the slip ring seal must ensure a seal under various operating conditions of the compressor or gas compressor. Typically, the barrier gas system operates when the compressor or gas compressor is stationary, supplying a barrier gas to the slip ring seal at a pressure slightly higher than that of the gas to be sealed. Thus, minimal leakage of the barrier gas can reach the product chamber via the seal gap of the slip ring seal. A special situation may arise when the compressor is pre-pressurized, i.e., when pressure is applied during compressor startup. In this case, the pressure of the gas to be sealed can become very high for a short time, especially higher than the pressure of the barrier fluid at the slip ring seal. The large volume of the barrier gas passage in the barrier gas system facilitates this behavior. However, this results in backflow of the gas to be sealed into the barrier gas passage. This backflow can cause a significant pressure drop across the seal gap of the slip ring seal, causing the seal gap to open. This can lead to excessive leakage of the gas to be sealed, which is then, for example, directed to the return passage (main vent). This can then lead to exceeding the alarm threshold because too much gas to be sealed reaches the return path. This can then cause the compressor to stop instead of starting as intended, in order to prevent the gas to be sealed, such as natural gas, from flowing out of the return path. This type of compressor is used, for example, at compressor stations along gas pipelines. Summary of the Invention
[0003] Therefore, the object of the present invention is to provide a slip ring sealing assembly that, while having a simple construction and simple, low-cost manufacturability, can achieve a reliable seal even during the start-up process of the machine to be sealed.
[0004] This objective is achieved by a slip ring sealing assembly having the features of technical solution 1. Dependent technical solutions illustrate preferred improvements of the invention.
[0005] The slip ring sealing assembly according to the invention, having the features of technical solution 1, has the advantage of achieving a reliable seal under all operating conditions, even during startup of the compressor or gas compressor to be sealed by the slip ring sealing assembly. This is achieved according to the invention by comprising a slip ring seal having a rotating slip ring and a stationary slip ring defining a sealing gap between them. The stationary slip ring has a through opening extending from the rear side of the stationary slip ring to a sliding surface at the sealing gap. The slip ring sealing assembly also includes a blocking fluid system configured to supply blocking fluid to the sealing gap at the slip ring seal. The blocking fluid system includes a supply passage for blocking fluid that directs the blocking fluid to a blocking fluid chamber at the rear side of the stationary slip ring. The slip ring sealing assembly also includes a flow diode. The flow diode is a fluid diode that can be flowed from the blocking fluid system toward the slip ring seal in a first flow direction, and similarly can be flowed from the slip ring seal toward the blocking fluid system in a second flow direction opposite to the first flow direction. The flow diode has a first flow resistance in the first flow direction, which is less than a second flow resistance in the second flow direction. Therefore, the flow diode is specifically configured to allow a first quantity M1 to flow in the first flow direction and a second quantity M2 to flow in the second flow direction. Here, the first quantity M1 is greater than the second quantity M2. The flow diode is arranged in the supply passage between the fluid blocking system and the slip ring seal.
[0006] Therefore, the flow diode is a valve device that has lower flow resistance in the preferred direction than in the opposite direction. Thus, the flow diode is installed in the supply passage such that the main flow direction of the flow diode is from the barrier gas system to the slip ring seal, because it is essential to ensure that a sufficient amount of barrier gas is supplied to the slip ring seal.
[0007] The first amount M1 in the main flow direction is significantly larger than the second amount M2 in the opposite blocking direction of the flow diode, preferably at least 10 times larger. It should be noted that, due to its principle, the flow diode can never completely prevent backflow in the opposite direction, and a small amount of fluid can always flow through in the opposite direction as well.
[0008] Particularly preferably, the flow diode is constructed as a fluid diode without any moving parts. Therefore, the flow diode does not have any moving parts. This makes it particularly suitable for use in locations where maintenance is quite difficult, such as at compressor stations of gas pipelines, which can typically be thousands of kilometers long and often extend into inaccessible areas.
[0009] When the flow diode is preferably positioned directly at the outlet of the supply passage leading to the barrier fluid chamber, particularly good adaptability is achieved to prevent pressure fluctuations and leakage of the gas to be sealed during compressor startup, with the outlet located behind the stationary slip ring.
[0010] By using a flow diode with external threads, a particularly low-cost design and easy installation are achieved, allowing the flow diode to be screwed into and out of the supply passage. This also allows for the simple retrofitting of existing slip ring seal assemblies in the field. Simply cut threads in the supply passage, and then screw the threaded flow diode into the threads.
[0011] Particularly preferably, the flow diode is configured as a headless screw thread with a tool attachment. The headless screw thread essentially has a cylindrical structure with external threads, wherein flow is achieved through the internal region of the headless screw thread in the longitudinal direction.
[0012] Particularly preferably, the flow diode is configured such that it has a tapered inlet, a throttling orifice, and a cone with a front end pointing towards the tapered inlet. The front end of the cone is preferably rounded in a manner consistent with hydrodynamics.
[0013] More preferably, the tip of the cone is guided through a throttling orifice. Preferably, the cone has a recess at an end opposite to the tip. The recess is preferably a partially spherical notch. This significantly reduces leakage in the opposite direction to the main flow direction.
[0014] Preferably, the cone is secured to the housing of the flow diode by means of an arm shaped in a hydrodynamic manner.
[0015] The throttling orifice preferably has an undercut in the second flow direction, thereby generating a reverse flow within the flow diode.
[0016] According to a preferred alternative of the invention, the flow diode has a Tesla-shaped flow-through region with a straight through channel and at least one flow loop. The flow loop has an inlet and an outlet arranged at the through channel. When the flow diode flows through in a second flow direction, the flow inside the flow diode is substantially opposite in direction at the outlet of the flow loop to the flow at the inlet. Preferably, a plurality of flow loops are arranged in a row in the through channel.
[0017] The through-channel is preferably eccentrically positioned within the flow diode.
[0018] According to another preferred alternative of the invention, the flow diode includes a throttling orifice, wherein the orifice has an exit with a right-angled side in a first flow direction and an inlet, such as a joint or rounded portion, conforming to hydrodynamics in the first flow direction. Thus, the exit and inlet of the orifice of the flow diode are constructed differently. This similarly defines the main flow direction as the first flow direction and enables reduced flow in the opposite direction.
[0019] In addition to the orifice, the flow diode preferably also has a first fluid chamber and a second fluid chamber, wherein the orifice is disposed between the first and second fluid chambers in the flow diode. Preferably, at least one of the fluid chambers has a tool attachment portion.
[0020] The slip ring sealing assembly is preferably configured as a series assembly and includes a first slip ring seal and a second slip ring seal connected in a row.
[0021] Therefore, the second slip ring seal serves as a safety seal, preventing the product from reaching the atmosphere in the event of failure of the first slip ring seal. The main vent is located between the first and second slip ring seals.
[0022] Preferably, the fluid barrier system further includes a nitrogen source, particularly a nitrogen tank. Preferably, a nitrogen generator is also provided. This allows nitrogen to be generated from ambient air and, for example, temporarily stored in the nitrogen tank. The fluid barrier system preferably includes a differential pressure valve configured to adjust the pressure level of the fluid barrier directed to the supply path of the fluid barrier system and, consequently, to the slip ring.
[0023] To monitor the slip ring sealing assembly, it preferably includes a monitoring mechanism arranged in the return path, which sends a fault signal, for example, to a dispatch center, when gas to be sealed is detected. Attached Figure Description
[0024] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. In the drawings:
[0025] Figure 1 A schematic cross-sectional view of a slip ring sealing assembly according to a first preferred embodiment of the present invention is shown.
[0026] Figure 2 It shows Figure 1 A schematic cross-sectional view of the flow diode of the slip ring sealing assembly during flow along the first flow direction.
[0027] Figure 3 It shows Figure 1 A schematic cross-sectional view of the flow diode of the slip ring sealing assembly during flow along the second flow direction.
[0028] Figure 4 A cross-sectional view of the flow diode according to a second embodiment of the present invention is shown when flow occurs along a first flow direction.
[0029] Figure 5 A cross-sectional view of the flow diode according to a second embodiment of the present invention is shown, showing the flow through it along a second flow direction.
[0030] Figure 6 A flow diode of a slip ring sealing assembly according to a third embodiment of the present invention is shown, and
[0031] Figure 7 A flow diode of a slip ring sealing assembly according to a fourth embodiment of the present invention is shown. Detailed Implementation
[0032] exist Figures 1 to 3 The image shows a gas-lubricated slip ring seal assembly 1 according to a first embodiment of the present invention.
[0033] The slip ring seal assembly 1 includes a first slip ring seal 2 and a second slip ring seal 3. The two slip ring seals are arranged in a row at the shaft 8 and seal the product chamber 40 from the atmosphere 41. This involves a so-called tandem arrangement, in which the first slip ring seal 2 and the second slip ring seal 3 are arranged in a row.
[0034] The first slip ring seal 2 includes a first rotating slip ring 21 and a first stationary slip ring 22, which define a first sealing gap 23 between their sliding surfaces. In this case, the first rotating slip ring 21 has a sliding surface 21a, and the first stationary slip ring 22 has a sliding surface 22a. Furthermore, the first slip ring seal 2 includes a first preload element 24, which preloads the first stationary slip ring 22 in the direction of the central axis XX of the slip ring seal assembly. The first stationary slip ring 22 is fixed to the housing 9.
[0035] The second slip ring seal 3 includes a second rotating slip ring 31 and a second stationary slip ring 32, which define a second sealing gap 33 between their sliding surfaces. In this configuration, the second rotating slip ring 31 is secured to the shaft 8 by means of a second slip ring support 36. A second preload element 34 preloads the second stationary slip ring 32 toward the second rotating slip ring 31.
[0036] The slip ring seal assembly 1 is a gas-lubricated slip ring seal assembly with a barrier fluid system 100, wherein a barrier fluid in the form of nitrogen is provided. For this purpose, the barrier fluid system 100 includes a nitrogen source 13, which supplies nitrogen to the first slip ring seal 2 via a supply passage 11.
[0037] As from Figure 1As can be seen, a through opening 25 is provided in the first stationary slip ring 22, which leads from the rear side 22b to the sliding surface 22a of the first stationary slip ring 22. The through opening 25 is straight and parallel to the central axis XX.
[0038] Reference numeral 14 indicates a nitrogen generator capable of extracting nitrogen from the air and supplying it to a nitrogen source 13, such as a nitrogen tank.
[0039] As from Figure 1 As can be seen, the supply passage leads into the fluid barrier chamber 50, which is located on the rear side of the first stationary slip ring 22.
[0040] exist Figure 1 In normal operation, the flow path of the barrier fluid is shown by the arrow, and it flows from nitrogen source 13 through supply passage 11 into barrier fluid chamber 50 and then to through opening 25. The pressure of the barrier fluid here is slightly higher than the pressure of the medium to be sealed in product chamber 40, causing a small portion of nitrogen gas, as leakage L, to also flow into product chamber 40. Since the product here is a methane-containing gas, the contamination of the product to be sealed due to nitrogen is negligible, especially since the amount involved in this case is very small.
[0041] The main portion of the barrier fluid escapes radially inside the first slip ring seal 2 at the first sealing gap 23, and then flows toward the second slip ring seal 3, from where it flows into the return passage (main vent) 12. The barrier fluid can then be discharged to the atmosphere from the return passage 12.
[0042] As from Figure 1 As can be seen, a first auxiliary seal 4 and a centering mechanism 5 are arranged at the first rotary slip ring 21. The first auxiliary seal 4 is located at the rear side 21b of the first rotary slip ring 21. In this case, the first rotary slip ring 21 is fastened to the shaft 8 by means of a first slip ring support 26. A groove 27 is provided in the first slip ring support 26, and the first auxiliary seal 4 is arranged in the groove. In this embodiment, the first auxiliary seal 4 is an O-ring with a circular cross-section, which is only used for sealing at the rear side 21b of the first rotary slip ring 21.
[0043] The centering mechanism 5 is a ring-shaped tension spring. The centering mechanism 5 is located on the radially inner surface 21c of the first rotating slip ring 21, which is opposite to the radially outer surface 21d. The centering mechanism 5 is used to center the first rotating slip ring 21. Therefore, the centering mechanism 5 does not have a sealing function, but only a centering function. Because the centering of the first rotating slip ring is thus achieved through the centering mechanism 5, the first auxiliary seal 4 is optimally designed for its sealing task at the rear side 21b.
[0044] The second auxiliary seal 6 and the third auxiliary seal 7 are arranged at the rear side 22b of the first stationary slip ring 22. As can be seen from Figure 1 in this case, a retaining ring 18 is provided at the rear side 22b, which has grooves for receiving the second auxiliary seal 6 and the third auxiliary seal 7, respectively. The second auxiliary seal and the third auxiliary seal are arranged such that the fluid path for the barrier fluid is guided between the second auxiliary seal 6 and the third auxiliary seal 7. In this case, through openings 18a are also arranged in the retaining ring.
[0045] As can be seen from Figure 1 the first auxiliary seal 4 has a first radius R1 measured from the central axis X-X of the slip ring seal assembly. The second auxiliary seal 6 has a second radius R2, and the third auxiliary seal 7 has a third radius R3. As can be seen from Figure 1 the first radius R1 is in between the second radius R2 and the third radius R3 in this case. Thereby, the inequality R2 < R < R3 is satisfied. Thereby, in particular, tilting of the slip rings of the first slip ring seal 2 can be avoided. Thereby, the first seal gap 23 can be maintained as constant and of small size during operation, such that the leakage L of the barrier fluid into the product can be minimized.
[0046] The slip ring seal assembly 1 further includes a differential pressure regulating valve 17 and a control unit 10 in the supply passage 11. In addition, a flow sensor 15 is arranged in the supply passage 11, which measures the flow rate through the supply passage 11. A pressure sensor 19 is arranged at the product chamber 40 and transmits the product pressure to the control unit 10.
[0047] During normal operation, the control unit 10 is set to adjust the pressure level in the barrier fluid chamber 50 in front of the first slip ring seal 2 based on the pressure in the product chamber 40. Thereby, the pressure in the second chamber 60 between the first slip ring seal 2 and the second slip ring seal 3 is automatically obtained, which is lower than the pressure in the barrier fluid chamber 50. In this case, the control unit 10 can control the opening or closing degree of the differential pressure regulating valve 17.
[0048] In this case, the opening or closing degree of the differential pressure regulating valve 17 is determined based on the product pressure. In this case, the pressure in the barrier fluid chamber 50 is adjusted via the adjustable differential pressure regulating valve 17 such that the pressure in the barrier fluid chamber 50 is always greater than the product pressure in the product chamber 40. Due to the throttling of the path of the barrier fluid, the pressure in the barrier fluid chamber 50 is also always greater than the pressure in the second chamber 60.
[0049] This ensures zero emissions of the product from the product chamber 40 in the direction toward the atmosphere 41. Thus, the gas-lubricated tandem slip ring seal assembly is particularly effective for sealing gases containing natural gas or methane. Maintenance-free operation is achieved through the simple and robust construction of the slip ring seal assembly 1. If the first slip ring seal 2 is damaged or fails for other reasons, the second slip ring seal 3 serves as a safety seal. Therefore, a seal relative to the atmosphere 41 is ensured by the second slip ring seal 3 even as the shaft 8 continues to rotate.
[0050] Furthermore, a monitoring mechanism 16 is arranged in the return path 12, which monitors the function of the slip ring seal assembly and can, for example, send a corresponding fault signal to the dispatch center in the event of slip ring seal assembly failure or damage. This ensures that the first slip ring seal 2 can be repaired as quickly as possible in the event of failure. The monitoring mechanism 16 can determine the damage to the first slip ring seal 2, for example, based on the pressure level in the return path 12 and / or based on the flow rate of the blocked fluid. Furthermore, the slip ring seal assembly according to the invention can operate without an intermediate seal, which, for example, is a labyrinth seal located between the first slip ring seal 2 and the second slip ring seal 3. This further simplifies manufacturing and, in particular, reduces manufacturing costs. Another advantage of the slip ring seal assembly 1 according to the invention is its compact construction. Therefore, the slip ring seal assembly 1 is particularly suitable for replacing slip ring seal assemblies already installed in compressor stations, such as pipelines. In particular, the slip ring seal assembly 1 according to the invention is suitable for applications up to approximately 160.10 mm in length. 5 Pa is a very high pressure.
[0051] As from Figure 1 It can also be seen that a flow diode 110 is arranged in the supply passage 11. The flow diode is a fluid diode without a moving component. The flow diode 110 is arranged directly at the inlet of the supply passage 11 at the fluid isolation chamber 50.
[0052] The flow diode 110 is configured to allow a first amount M1 of the blocked fluid to flow in a first flow direction A, which corresponds to the flow direction (main flow direction) of the blocked fluid during normal operation. This is in Figure 2 As can be seen in detail, the flow diode 110 is shown in cross-sectional view.
[0053] The second quantity M2 of the medium can flow back through the flow diode in the second flow direction B, which is opposite to the first flow direction A, so that the flow diode essentially provides a blockage in the second flow direction (see...). Figure 3 ).
[0054] The first quantity M1 is much larger than the second quantity M2, preferably at least 10 times larger. Therefore, the cross-flow diode has different flow resistances in the two cross-flow directions.
[0055] As from Figure 2 and Figure 3 As can be seen in the detailed view, the flow diode 110 has an external thread 111 and is provided as a headless screw and screwed into the supply passage 11. Flow through the flow diode 110 is achieved through its internal structure.
[0056] The tool can be screwed into the supply passage 11 via the external thread 111 using the tool attachment 112, and the tool can function in the tool attachment.
[0057] The flow diode 110 also includes a tapered inlet 113, a throttling orifice 114, and a cone 116. An undercut 115 is provided at the throttling orifice 114 on the side pointing towards the fluid-blocking chamber 50. The cone 116 has a rounded front end 116a and a recess 116b at the end opposite to the front end 116a. The recess 116b points towards the fluid-blocking chamber 50. The cone 116 is secured to the generally cylindrical housing component 118 of the flow diode 110 by means of arms 117, such as two, three, or four arms, shaped in a hydrodynamic manner.
[0058] As from Figure 2 As can be seen, the cone 116 is arranged such that the front end 116a passes through the throttling orifice 114 of the flow diode 110 in the axial direction YY of the flow diode.
[0059] Figure 2 The first flow direction A through the flow diode 110 during normal operation is shown. The barrier fluid is guided through the throttle orifice 114 via the tapered inlet 113 and accelerated into the barrier fluid chamber 50 in the direction toward the escape region due to the hydrodynamically conforming cone 116. Thus, a large amount of barrier fluid can be supplied to the first slip ring seal 2 through the barrier fluid system 100.
[0060] If an abnormal operation of the slip ring seal assembly occurs, for example, during machine startup, and the pressure in the product chamber 40 exceeds the barrier fluid pressure, this increased pressure propagates through the first sealing gap 23 and the through opening 25 to the barrier fluid chamber 50. This results in backflow from the barrier fluid chamber 50 to the supply passage 11. This... Figure 3This is indicated by arrow B. Due to the blocking effect of the flow diode 110 in this second flow direction B, minimal flow is obtained only in this direction through the flow diode 110, as indicated by arrow B. Backflow in the second flow direction is obtained even before the throttling orifice 114 through the undercut 115, which very effectively prevents the fluid from flowing further through the flow diode 110 towards the supply passage 11.
[0061] Figure 3 The opposite flow direction B through the flow diode 110 is shown, which is strictly limited due to the construction of the flow diode 100. In particular, backflow even occurs through the undercut 115 at the throttling orifice 114, which makes it significantly more difficult for flow to pass through the flow diode in the direction of the second flow direction B, which is a surrounding channel with an arcuate cross-section.
[0062] Therefore, combined with the small cross-section at the throttling orifice 114, when the machine is started, only a minimum portion of the fluid can flow out of the barrier fluid chamber 50 in the second flow direction B.
[0063] This prevents the pressure drop in the fluid isolation chamber 50 from becoming too large and the first sealing gap 23 from opening too wide, which could cause the process fluid to flow out into the return passage 12 through the open sealing gap 23.
[0064] The slip ring seal assembly 1, which is already in the field, can also be easily modified by constructing the flow diode 110 as a headless screw connection.
[0065] Figure 4 and Figure 5 A flow diode 120 of a slip ring sealing assembly according to a second embodiment of the present invention is shown. Identical or functionally identical components are indicated by the same reference numerals as in the first embodiment.
[0066] The flow diode 120 in the second embodiment is also constructed as a headless screw with external threads 121. Reference numeral 122 indicates a tool attachment for screwing into the flow diode 120.
[0067] The flow diode 120 has a configuration similar to a Tesla valve. The flow diode 120 includes a straight through channel 123 and a flow loop 124 arranged in the through channel. The flow loop has an inlet 124a and an outlet 124b, which are respectively arranged in the through channel 123.
[0068] When in Figure 4 When the flow diode 120 of the second embodiment is passed through during normal operation, a substantially continuous flow is obtained through the through-channel 123. The medium is substantially stationary in the flow loop 124. This is in Figure 4Arrow A indicates the first flow direction of the flow diode 120.
[0069] However, if the flow direction is reversed by 180°, such as Figure 5 As shown, the medium flows from the barrier fluid space 50 into the through channel 123 and the flow loop 124. In the flow loop 124, the medium is almost turned 180°, resulting in two opposing flows inside the flow diode 120, which effectively prevents a large amount of medium from the barrier fluid space 50 from flowing through the supply passage 11.
[0070] It should be noted that multiple flow loops can also be set up.
[0071] Therefore, the flow diode 120 has no moving parts and is virtually maintenance-free, and since leakage is minimal and the pressure rise in the blocked fluid chamber 50 takes only a very short time, there is no risk of the first slip ring seal opening and the product medium reaching the atmosphere.
[0072] Figure 6 A flow diode 130 with external threads 133 is shown according to a third embodiment of the invention. Components that are identical or functionally identical are again indicated by the same reference numerals as in the foregoing embodiments.
[0073] The flow diode 130 of the third embodiment is a throttling orifice, having an exit 131 with a right-angled side at the fluid-blocking chamber 50 and an inlet 132 at the opposite end that is processed in a hydrodynamic manner. The inlet 132 is chamfered. Thus, in Figure 6 The relatively smooth flow through the flow diode 130 of the third embodiment, as shown during normal operation, is indicated by arrow A, which points to the first flow direction. For simplicity, in Figure 6 A second flow direction opposite to the first flow direction A is not shown. However, the exit point 131 of the right-angled side (where the medium has to enter the throttling orifice when flowing through the flow diode 130) hinders a smooth transition, causing eddies to form there, and the amount of medium flowing in the second flow direction is much smaller than the amount flowing in the first flow direction A. In other respects, this embodiment corresponds to the previous embodiment, and reference can be made to the description given therein.
[0074] Figure 7A flow diode 140 with external threads 145 is shown as a slip ring sealing assembly according to a fourth initial example of the invention. Identical or functionally equivalent components are again indicated by the same reference numerals as in the foregoing embodiments. The flow diode 140 of the fourth embodiment is also an orifice and is constructed similarly to the flow diode of the third embodiment. The flow diode 140 has an exit 141 with right-angled edges and a treated inlet 142. The flow diode 140 also includes a first fluid chamber 143 at the exit 141 and a second fluid chamber 144 at the inlet 142. Figure 7 As can be seen, the first fluid chamber 143 points towards the blocking fluid chamber 50 and enters it with a right-angled edge. The second fluid chamber 144 points towards the supply passage 11 and has an inlet edge 144a shaped in a hydrodynamic manner. The diameters of the first fluid chamber 143 and the second fluid chamber 144 are chosen to be the same. Therefore, due to the exit opening 141 of the right-angled edge and the processed inlet 142, which again has a tapered chamfer as in the third embodiment, the flow rate in the first flow direction A is different from the flow rate in the second flow direction B. The flow rate in the first flow direction A is significantly greater than the flow rate in the second flow direction B. Therefore, the flow diode 140 of the fourth embodiment is also suitable as a valve without moving parts.
[0075] In addition to the foregoing written description of the invention, reference is hereby made to the graphical representation of the invention in the accompanying drawings for further disclosure.
[0076] Explanation of reference numerals in the attached figures
[0077] 1. Slip ring sealing assembly
[0078] 2 First slip ring seal
[0079] 3 Second slip ring seal
[0080] 4 First auxiliary seal
[0081] 5. Reassurance Organization
[0082] 6 Second auxiliary seal
[0083] 7 Third auxiliary seal
[0084] 8-axis
[0085] 9 shells
[0086] 10 control units
[0087] 11 Supply Channels
[0088] 12 Return Path (Main Vent)
[0089] 13 Nitrogen Source
[0090] 14 Nitrogen Generator
[0091] 15 Flow Sensors
[0092] 16 monitoring agencies
[0093] 17 Adjustable differential pressure regulating valve
[0094] 18 retaining rings
[0095] 18a through opening
[0096] 19 pressure sensors
[0097] 21 First Rotating Slip Ring
[0098] 21a Sliding Surface
[0099] 21b rear side
[0100] 21c radial inner surface
[0101] 21d radial outer surface
[0102] 22 First stationary slip ring
[0103] 22a Sliding Surface
[0104] 22b rear side
[0105] 23 First sealing gap
[0106] 24 First preload element
[0107] 25 through opening
[0108] 26 First slip ring bearing component
[0109] 27 slots
[0110] 31 Second Rotary Slip Ring
[0111] 32 Second stationary slip ring
[0112] 33 Second sealing gap
[0113] 34 Second preload element
[0114] 36 Second slip ring bearing component
[0115] 40 Product Room
[0116] 41 Atmosphere
[0117] 50 barrier fluid chambers
[0118] Room 60, Second Room
[0119] 100-barrier fluid system
[0120] 110 flow diode
[0121] 111 external thread
[0122] 112 Tool Attachment
[0123] 113 Conical Inlet
[0124] 114 throttle orifices
[0125] 115 Undercut
[0126] 116 cone
[0127] The front end of the 116a cone
[0128] 116b concave part
[0129] 117 arms
[0130] 118 housing components
[0131] 120 Flow Diode
[0132] 121 external thread
[0133] 122 Tool Attachment
[0134] 123 Through Passage
[0135] 124 flow loop
[0136] 124a Import
[0137] 124b Export
[0138] 130 Flow Diode
[0139] 131 exit
[0140] 132 entrance
[0141] 133 external thread
[0142] 140 Flow Diode
[0143] 141 exit
[0144] Entrance 142
[0145] 143 First Fluid Chamber
[0146] 144 Second Fluid Chamber
[0147] 144a entrance edge
[0148] 145 external thread
[0149] A First flow direction
[0150] B Second flow direction
[0151] L leak
[0152] R1 First radius
[0153] R2 second radius
[0154] R3 third radius
[0155] XX central axis
[0156] Axial direction of YY flow diode
Claims
1. A gas-lubricated slip ring seal assembly, comprising: - A slip ring seal (2) having a rotating slip ring (21) and a stationary slip ring (22) defining a first sealing gap (23) between the rotating slip ring and the stationary slip ring on sliding surfaces (21a) and (22a). - A barrier fluid system (100) configured to supply barrier fluid to the sealing gap (23), - The stationary slip ring (22) has a through opening (25) for supplying the barrier fluid to the sealing gap (23) of the slip ring seal (2), wherein the through opening (25) extends from the rear side (22b) of the stationary slip ring (22) to the sliding surface (22a). - The fluid barrier system (100) includes a supply passage (11) for the fluid barrier, which directs the fluid barrier to the fluid barrier chamber (50) at the rear side (22b) of the stationary slip ring (22). - Flow diodes (110; 120; 130; 140), which have a first flow resistance in a first flow direction A from the barrier fluid system (100) toward the slip ring seal (2) and a second flow resistance in a second flow direction B opposite to the first flow direction A from the slip ring seal toward the barrier fluid system (100). - Wherein the first flow resistance is less than the second flow resistance, and - wherein the flow diode is arranged in the supply passage (11) between the slip ring seal (2) and the barrier fluid system (100).
2. The slip ring sealing assembly according to claim 1, wherein the flow diodes (110; 120; 130; 140) do not have movable components.
3. The slip ring sealing assembly according to any one of the preceding claims, wherein the flow diodes (110; 120; 130; 140) are directly disposed at the outlet of the supply passage (11) leading to the barrier fluid chamber (50).
4. The slip ring sealing assembly according to any one of the preceding claims, wherein the flow diodes (110; 120); (130); (140) have external threads (111); (121); (133); (145) so that they can be screwed into and out of the supply passage (11).
5. The slip ring sealing assembly according to claim 4, wherein the flow diode is a headless screw with a tool attachment (112; 122), and flow through the headless screw is achieved by passing the flow diode through the headless screw in the axial direction YY.
6. The slip ring sealing assembly according to any one of the preceding claims, wherein the flow diode (110) has a tapered inlet (113), a throttling orifice (114) and a cone (116) having a front end (116a) pointing toward the tapered inlet (113).
7. The slip ring sealing assembly according to claim 6, wherein the front end (116a) of the cone (116) is guided through the throttling orifice (114).
8. The slip ring sealing assembly according to claim 6 or 7, wherein the front end (116a) of the cone (116) is rounded.
9. The slip ring sealing assembly according to any one of claims 6 to 8, wherein the cone (116) has a recess (116b) at the end of the cone opposite to the front end (116a).
10. The slip ring sealing assembly according to any one of claims 1 to 5, wherein the flow diode (120) has a straight through channel (123) and at least one flow loop (124), wherein the flow loop (124) has an inlet and an outlet arranged at the straight through channel, wherein when the flow diode flows through in the first flow direction A, only the through channel (123) flows through, and when the flow diode flows through in the second flow direction B, the flow is directed into the through channel (123) and the flow loop (124), wherein the flow direction at the outlet of the flow loop is substantially opposite to the flow direction at the inlet of the flow loop.
11. The slip ring sealing assembly according to claim 10, wherein the straight through channel (123) is eccentrically arranged in the flow diode (120).
12. The slip ring sealing assembly according to any one of claims 1 to 5, wherein the flow diode (130; 140) includes a throttling orifice, wherein the throttling orifice has an exit (131; 141) with a right-angled side in the first flow direction A and an inlet (132; 142) in the first flow direction A in accordance with hydrodynamics.
13. The slip ring sealing assembly according to claim 12, wherein the flow diode (140) has a first fluid chamber (143) and a second fluid chamber (144), wherein the throttling orifice is arranged in the flow direction between the first fluid chamber (143) and the second fluid chamber (144).
14. The slip ring sealing assembly of claim 13, wherein at least one of the fluid chambers (143, 144) has a tool attachment to enable the flow diode to be screwed into the supply passage (11).