Air sealing system of steering oar

Abstract

The invention discloses an air sealing system for a steering oar, which relates to the technical field of ships and comprises an oar shaft seal, a steering seal, an input shaft seal, an air control unit, an oar shaft seal oil tank, a discharge and collection unit, an oar shaft seal lubricating oil pump unit, an input shaft seal oil tank and an input shaft seal lubricating oil pump unit, the invention discloses a full-rotation steering oar sealing oil tank. According to the air sealing system for the full-rotation steering oar, the sealing performance of the full-rotation steering oar is improved, the service life of the sealing system is prolonged, the risk of lubricating oil leakage is reduced, pollution to the environment is reduced, and the reliability of operation of the full-rotation steering oar in a complex water area is improved.

Description

Technical Field

[0001] The invention relates to the technical field of ships, and in particular to an air sealing system for an omni-rotating propeller. Background Art

[0002] Existing full-rotation propeller air sealing system, such as Figure 1 As shown, it is mainly composed of the following six parts: propeller shaft seal, rudder seal, input shaft seal, air control unit, and rudder propeller device seal oil tank discharge collection unit.

[0003] The input shaft seal is not introduced into the sealing system, so the input shaft seal ring is subjected to great pressure, and the wear between it and the input shaft bushing will be very serious, and the service life will be greatly reduced; and the input shaft adopts a single-channel sealing structure, which will generate serious heat under high linear speed conditions, and the risk of leakage will be further increased.

[0004] The propeller shaft seal and rudder seal do not have a lubricating oil pump unit, and the oil at the seal cannot be filtered and cooled. Under long-term operation, the internal impurity content will continue to increase, which will seriously affect the service life of the seal and may cause serious leakage risks and economic losses.

[0005] The number of sealing rings used to prevent lubricating oil leakage in the propeller shaft is too small. Once the #3 sealing ring fails, a large amount of oil inside the full-turn propeller body is at risk of being contaminated by seawater.

[0006] The air control system has no clean water flushing pipeline. Once the air pipeline is blocked, it cannot be repaired on site and can only be repaired in the dock, which poses a hidden danger to the navigation safety of the ship and also causes economic losses. Summary of the invention

[0007] The present invention provides an azimuth propeller air sealing system, which improves the sealing performance of the azimuth propeller, prolongs the service life of the sealing system, reduces the risk of lubricating oil leakage, reduces pollution to the environment, and improves the reliability of the azimuth propeller in operation in complex waters.

[0008] According to one aspect of the present disclosure, an air sealing system for an azimuth propeller is provided, the system comprising: a propeller shaft seal, a rudder seal, an input shaft seal, an air control unit, a propeller shaft seal oil tank and a discharge collection unit, the system further comprising: a propeller shaft seal lubricating oil pump unit, an input shaft seal oil tank, an input shaft seal lubricating oil pump unit, and an azimuth propeller seal oil tank; The compressed air on board is filtered, decompressed and flow-regulated by the air control unit before entering the annular cavity of the #2 / #3 sealing ring of the propeller shaft seal and the annular cavity of the #6 / #7 sealing ring of the rudder seal. A part of the air overcomes the tension of the #1, #2 sealing rings and the #5, #6 sealing rings themselves and the pressure of the seawater and is released into the seawater in the form of bubbles. The other part of the air enters the discharge unit J from the pipeline and is discharged into the air. The compressed air on board enters the propeller shaft seal oil tank after being filtered, decompressed and flow-regulated by the air control unit. Then the propeller shaft seal lubricating oil pump unit transports the oil in the propeller shaft seal oil tank through the annular cavity of the #7 / #8 seal ring of the steering seal to the annular cavity of the #3 / #4 seal ring of the propeller shaft seal. Then the oil passes through the annular cavity of the #9 / #10 seal ring of the steering seal and returns to the propeller shaft seal oil tank. The compressed air on board is filtered by the air control unit, decompressed, and the flow is adjusted. The air is decompressed again by the flow restrictor, and then enters the full-rotation propeller sealing oil tank. The oil in the full-rotation propeller sealing oil tank is connected to the oil inside the propeller body. The lubricating oil in the #11 / #12 chamber of the input shaft seal is the circulating oil provided by the input shaft seal lubricating oil pump unit. There is a height difference between the input shaft seal oil tank and the input shaft seal, which can control the pressure of the #11 / #12 chamber of the input shaft seal to be lower than the pressure in the full-rotation propeller body, and the pressure difference is controlled within 0.05MPa.

[0009] In a possible implementation, the structure of the propeller shaft sealing lubricating oil pump unit is as follows: the propeller shaft sealing lubricating oil pump unit includes: a double filter F3 and a filter F4, a motor M1 and a motor M2, a pressure sensor A5, a pressure gauge P6, a main pump PU1 and a standby pump PU2, and a first lubricating oil cooler; the main pump PU1 and the standby pump PU2 are connected in parallel; PU1 is the main pump and PU2 is the standby pump. When the pressure sensor A5 is lower than the set value, the standby pump PU2 is enabled. Motor M1 is used to drive the PU1 main pump, and motor M2 is used to drive the PU2 standby pump; The upstream and downstream of the PU1 main pump are connected in series with valve V18 and non-return valve D7 respectively; the upstream and downstream of the PU2 standby pump are connected in series with valve V19 and non-return valve D8 respectively; the upstream of the PU1 main pump is connected to the input shaft sealing oil tank; The downstream of the PU1 main pump is connected to the pressure gauge P6 through valve V21 and to the pressure differential transmitter through V20; The duplex filter F3 and filter F4 are equipped with one-way valve D10, one-way valve D11 and differential pressure transmitter A6. When the filter F3 is blocked, the differential pressure transmitter A6 sends out an alarm signal, the one-way valve D10 opens, and the oil flows from the one-way valve D10 to the pipeline behind. At this time, switch the handle of the duplex filter to the other side, activate the filter F4, and remove the filter element of the filter F3 for cleaning or replacement; The first lubricating oil cooler is connected to the downstream of the duplex filter F3 and the filter F4. A one-way valve D9 is connected in parallel to the first lubricating oil cooler. When the cooler is blocked, the oil will enter the full-turn propeller through the one-way valve D9. At this time, valves V22 and V23 are closed, and the cooler is removed for maintenance. WI1 and WO1 of the first lubricating oil cooler are respectively the first lubricating oil cooler water inlet and the first lubricating oil cooler water outlet.

[0010] In a possible implementation, the input shaft seal oil tank includes valve 25 and valve 31, the input shaft seal lubricating oil pump unit is connected via valve 25, and the input shaft seal is connected via valve 31. The input shaft seal oil tank is also equipped with an oil level high and low alarm switch A7, and also includes a discharge valve V32; The functions of the input shaft seal oil tank include: providing lubricating oil to the input shaft seal lubricating oil pump unit, providing pressure to the annular cavity of the #11 / #12 seal ring of the input shaft seal, and offsetting part of the pressure inside the full-rotation propeller on the #11 seal ring.

[0011] In a possible implementation, the input shaft seal lubricating oil pump unit includes: a filter F5, a motor M3 and a motor M4, a main pump PU3 and a standby pump PU4, a pressure gauge P7, and a pressure sensor A8; The filter F5 is equipped with a one-way valve D12 and a differential pressure transmitter A9. When the filter F5 is clogged, the differential pressure transmitter A9 sends out an alarm signal, the one-way valve D12 opens, and the oil flows from the one-way valve D12 into the chamber of the input shaft seal ring; The upstream of the main pump PU3 and the standby pump PU4 is connected to the input shaft sealing oil tank, and the downstream of the main pump PU3 and the standby pump PU4 is connected to the filter F5. The downstream of the main pump PU3 and the standby pump PU4 is also connected to the pressure difference transmitter A8 and the pressure gauge P7 through valve V29 and valve V28 respectively; The upstream of main pump PU3 is connected in series with valve V26 and the downstream is connected in series with check valve D13, and the upstream of standby pump PU4 is connected in series with valve V27 and the downstream is connected in series with check valve D14; Pump PU3 and pump PU4 are used as one for use and one for backup. When the pressure sensor A8 is lower than the set value, the backup pump PU4 is activated; The upstream of the pump PU3 and the downstream of the filter F5 are connected via a ball valve V30.

[0012] In a possible implementation, the fully rotating propeller sealed oil tank includes: a safety valve SV2, an air pressure high alarm switch A10, an air pressure low alarm switch A11, and an oil level high and low alarm switch A12; The high air pressure alarm switch A10 and the low air pressure alarm switch A11 are connected to the oil tank through valve V33 and valve V34 respectively, and the full-turn propeller sealing oil tank discharges lubricating oil through the normally closed ball valve V35; The sealed oil tank of the azimuth steering propeller is connected to the air control unit through a flow restrictor, and the sealed oil tank of the azimuth steering propeller is input to the azimuth steering propeller through a valve 36 .

[0013] Compared with the prior art, the present invention has the following beneficial effects: The purpose of the present invention is to provide an air sealing system for an omni-rotating propeller. The present invention is an air sealing system for a fully rotating propeller, which is mainly composed of the following ten parts: propeller shaft seal, steering seal, input shaft seal, air control unit, propeller shaft seal oil tank, propeller shaft seal lubricating oil pump unit, input shaft seal oil tank, input shaft seal lubricating oil pump unit, fully rotating propeller seal oil tank, and discharge collection unit. Through the application of this system, the sealing performance of the fully rotating propeller is improved, the service life of the sealing system is extended, the risk of lubricating oil leakage is reduced, the pollution to the environment is reduced, and the reliability of the fully rotating propeller in operation in complex waters is improved.

[0014] The full-revolving propeller air sealing system forms all the seals of the full-revolving propeller system into a whole by adding a propeller shaft sealing oil tank, a propeller shaft sealing lubricating oil pump unit, an input shaft sealing oil tank, and an input shaft sealing lubricating oil pump unit, so that the pressure on each seal can be controlled below 0.05MPa, which can effectively improve the sealing effect of the sealing ring and extend its service life.

[0015] The input shaft seal oil tank and input shaft seal lubricating oil pump unit were introduced, and the traditional single-pass seal structure was changed to a double-pass seal structure. Both seals are oil lubricated, and the oil can circulate, which has the effect of heat dissipation and cooling, improving the operating conditions of the input shaft seal ring. High and low liquid level sensors were introduced, so that once a leak occurs, the fault can be discovered and eliminated in time.

[0016] A flow restrictor is added in front of the fully rotating propeller sealing oil tank to reduce the pressure on the input shaft #11 seal ring, making it unnecessary to use a high-pressure resistant seal, reducing procurement costs, and enabling the entire fully rotating propeller to adapt to working conditions with deeper drafts, thereby increasing the scope of use of the fully rotating propeller.

[0017] A propeller shaft seal oil tank has been added, and the propeller shaft seal structure has been changed from 3 seals to 4 seals. Once the propeller shaft seal #3 fails, the oil in the propeller shaft seal will be contaminated first and the liquid level will be lowered, making it easier for engine management personnel to promptly discover and eliminate hidden dangers. The propeller shaft seal oil tank contains less oil and will not cause large-scale oil pollution, causing little damage to the environment. This avoids the previous 3-seal structure, which would cause large-scale water pollution once the #3 seal fails.

[0018] The air control unit has added a fresh water cleaning pipeline. Once the air pipeline is blocked, you only need to switch the three-way stopcock of the air control unit to the fresh water flushing pipeline when the main engine is shut down to clean the air pipelines of the propeller shaft seal and the rudder seal. There is no need to dock for maintenance, which shortens the maintenance cycle and greatly reduces the economic losses caused by maintenance and shutdowns.

[0019] Compared with the traditional air sealing system, the full-rotation propeller air sealing system combines the propeller shaft seal, the steering seal, the input shaft seal and the pressure state inside the full-rotation propeller to form a whole.

[0020] Introducing a sealing oil tank and a lubricating oil pump unit at the input shaft seal can change the traditional single-pass sealing structure of the input shaft into a double-pass sealing structure, and can also circulate the lubricating oil, filter out impurities, and reduce the oil temperature.

[0021] The sealing oil tank of the azimuth propeller is equipped with a flow restrictor, which reduces the pressure inside the azimuth propeller body, reduces the risk of seal leakage, and reduces the purchase cost of the seal ring.

[0022] The number of sealing rings in the propeller shaft seal oil tank, propeller shaft seal and rudder seal has been increased, which will provide effective early warning of sealing ring failure and oil leakage, avoiding the risk of large-scale pollution caused by large-scale oil leakage inside the rudder propeller.

[0023] The air control unit has introduced a fresh water flushing system, which greatly reduces the economic losses caused by docking maintenance and shutdown. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A block diagram of an existing fully rotating propeller air sealing system according to an embodiment of the present disclosure is shown.

[0025] Figure 2 A block diagram of an improved azimuth propeller air sealing system according to an embodiment of the present disclosure is shown.

[0026] Figure 3 A diagram showing a propeller shaft seal structure according to an embodiment of the present disclosure is shown.

[0027] Figure 4 A diagram showing a steering seal structure according to an embodiment of the present disclosure is shown.

[0028] Figure 5 A diagram showing the input shaft seal structure of an embodiment of the present disclosure is shown.

[0029] Figure 6 A schematic diagram of an air control unit according to an embodiment of the present disclosure is shown.

[0030] Figure 7 A propeller shaft sealing oil box according to an embodiment of the present disclosure is shown.

[0031] Figure 8 A propeller shaft seal lubricating oil pump unit according to an embodiment of the present disclosure is shown.

[0032] Fig. 9 An input shaft seal oil tank according to an embodiment of the present disclosure is shown.

[0033] Fig.10 An input shaft seal lubricating oil pump unit according to an embodiment of the present disclosure is shown.

[0034] Fig.11 A sealed oil tank for an azimuth propeller according to an embodiment of the present disclosure is shown.

[0035] Fig.12 A discharge collection unit according to an embodiment of the present disclosure is shown.

[0036] Description of the reference numerals: 1-propeller shaft, 2-propeller shaft bushing, 3-sealing gasket 1, 4-end cover, 5-middle flange ring 1, 6-middle flange ring 2, 7-middle flange ring 3, 8-sealing gasket 2, 9-mounting flange ring, 10-lower gear box, 11-O-ring, 12-lip seal ring, 13-anti-sediment seal ring, 14-rudder seal ring (5 groups), 15-rudder seal seat, 16-spacer, 17-rudder seal bushing, 18-O-ring 1 (5 groups), 19-well, 20-O-ring 2, 21-cover plate, 22-packing, 23- O-ring 3 (5 groups), 24-steering tube, 25-upper gearbox, 26-spherical roller bearing, 27-input shaft, 28-input shaft sealing bushing, 29-O-ring 1, 30-pipe joint 1, 31-spacer, 32-lip seal (two groups), 33-locking nut, 34-O-ring 2, 35-dust ring, 36-pressure plate, 37-input shaft sealing seat, 38-pipe joint 2. DETAILED DESCRIPTION

[0037] Various exemplary embodiments, features and aspects of the present disclosure will be described in detail below with reference to the accompanying drawings. The same reference numerals in the accompanying drawings represent elements with the same or similar functions. Although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless otherwise specified.

[0038] The word “exemplary” is used exclusively herein to mean “serving as an example, example, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.

[0039] In addition, in order to better illustrate the present disclosure, numerous specific details are given in the following specific embodiments. It should be understood by those skilled in the art that the present disclosure can also be implemented without certain specific details. In some examples, methods, means, components and circuits well known to those skilled in the art are not described in detail in order to highlight the subject matter of the present disclosure.

[0040] according to Figure 2 The working principle of the fully rotating propeller air sealing system is described as follows: The compressed air on board is filtered, decompressed and adjusted by the air control unit before entering the annular cavity of the #2 / #3 seal ring of the propeller shaft seal and the annular cavity of the #6 / #7 seal ring of the rudder seal. A part of the air is released into the seawater in the form of bubbles after overcoming the tension of the #1, #2 seal rings and the #5, #6 seal rings and the pressure of the seawater, and the other part of the air is discharged into the air after entering the discharge unit from the pipeline. According to the classical principles of physics, the pressure at any point under the water surface is proportional to the height from that point to the water surface, so the change in the ship's draft can be determined by detecting the air pressure. Any change in the ship's draft can be automatically tracked by the air control unit and the output pressure and the oil pressure at the propeller shaft seal and the rudder seal can be automatically adjusted to prevent seawater from invading the interior of the full-turn rudder propeller and the lubricating oil from leaking out of the ship.

[0041] The compressed air on board is filtered, decompressed and flow-regulated by the air control unit before entering the propeller shaft sealing oil tank. Then the propeller shaft sealing lubricating oil pump unit transports the oil in the propeller shaft sealing oil tank through the annular cavity of the #7 / #8 sealing ring of the steering seal to the annular cavity of the #3 / #4 sealing ring of the propeller shaft seal. Then the oil passes through the annular cavity of the #9 / #10 sealing ring of the steering seal and returns to the propeller shaft sealing oil tank E. Because there is a certain height difference between the propeller shaft sealing oil tank and the propeller shaft, it is necessary to simultaneously control the pressure in the annular cavity of the #3 / #4 sealing ring to be greater than the pressure in the annular cavity of the #2 / #3 sealing ring and the pressure in the annular cavity of the #7 / #8 sealing ring to be greater than the pressure in the annular cavity of the #6 / #7 sealing ring within 0.05MPa, which can effectively extend the service life of the #3 and #7 sealing rings, the propeller shaft bushing and the steering bushing.

[0042] The compressed air on board is filtered by the air control unit, decompressed, and the flow is adjusted. The air is decompressed again by the flow restrictor before entering the full-rotation propeller sealing oil tank. The oil in the full-rotation propeller sealing oil tank is connected to the oil inside the propeller body. Because the air is decompressed by the flow restrictor before entering the full-rotation propeller sealing oil tank, the pressure in the full-rotation propeller body can be controlled to be lower than the pressure in the #3 / #4 sealing ring cavity of the propeller shaft seal and the #9 / #10 sealing ring cavity of the steering rudder seal. The pressure difference is controlled within 0.05MPa, which can effectively extend the service life of the #4 sealing ring, #10 sealing ring, propeller shaft bushing and steering rudder bushing.

[0043] The lubricating oil in the #11 / #12 chamber of the input shaft seal is the circulating oil provided by the input shaft seal lubricating oil pump unit. There is a certain height difference between the input shaft seal oil tank and the input shaft seal, which can control the pressure of the #11 / #12 chamber of the input shaft seal to be lower than the pressure in the full-turn propeller body, and the pressure difference is controlled within 0.05MPa; the height between the input shaft seal oil tank and the input shaft seal is about 2m to prevent the #12 sealing ring from being subjected to excessive pressure.

[0044] Propeller shaft seal: The propeller shaft seal plays a dual role in preventing seawater from entering the full-revolving propeller and preventing the lubricating oil inside the full-revolving propeller from leaking into the seawater. The propeller shaft seal uses an air sealing system, which can separate seawater and lubricating oil through the air chambers #1 / #2 and #2 / #3 formed by compressed air, and the compressed air is blown out continuously and stably, which minimizes the mutual contamination between seawater and oil, and plays a positive role in protecting the marine environment and reducing the lubricating oil consumption of shipping companies. At the same time, through the integrated design with the full-ship automatic monitoring system, the operating status of the seal can be monitored in real time to improve the reliability and stability of the propeller device.

[0045] like Figure 3 The diagram shows the propeller shaft seal structure. The propeller shaft seal structure consists of a propeller shaft bushing 2, an end cover 4, an intermediate flange ring (sequence 5, sequence 6, sequence 7), a mounting flange ring 9, sealing gaskets 3 and 8, a lip seal 12, and an O-ring 11. The bushing of the propeller shaft seal is installed on the hub by bolts, and is sealed with the hub by a sealing gasket 1, and is sealed with the propeller shaft 1 by an O-ring 11; the mounting flange ring 9 is fixed to the lower gear box 10 of the full-turn propeller by bolts, and the mounting flange ring 9 and the lower gear box 10 are sealed by a sealing gasket 2. There are 4 lip seals inside the propeller shaft seal, with #1, #2 and #4 seals facing outwards and #3 seals facing inwards. When used for the first time, the #1 / #2 and #2 / #3 sealing chambers are filled with grease.

[0046] Steering seal: The steering seal plays a dual role in preventing seawater from entering the full-revolving propeller and preventing the lubricating oil inside the full-revolving propeller from leaking into the seawater. The steering seal uses an air sealing system, which can separate seawater and lubricating oil through the air chambers #5 / #6 and #6 / #7 formed by compressed air, and the compressed air is blown out continuously and stably, which minimizes the mutual contamination between seawater and oil, and plays a positive role in protecting the marine environment and reducing the lubricating oil consumption of shipping companies. At the same time, the steering seal acts as an air control unit and the middle channel connecting the propeller shaft seal with the propeller shaft seal tank, transporting air and lubricating oil to the propeller shaft seal through the annular cavity of the steering seal, and then transporting the lubricating oil back to the propeller shaft seal tank through the steering seal, and transporting the incoming seawater and leaked lubricating oil to the discharge unit.

[0047] like Figure 4 The diagram shows the structure of the steering seal. The steering seal structure consists of a lip seal ring 14, a steering seal seat 15, a spacer 16, a steering seal bushing 17, an O-ring 118, a well 19, an O-ring 2, a cover plate 21, a packing 22, an O-ring 323, and a steering tube 24. The steering seal bushing 17 is installed on the steering tube 24 by shrink fitting, and is sealed with the steering tube by an O-ring 3. The cover plate 21 is installed on the steering seal seat 15 by bolts, and is sealed with the steering seal seat 15 by an O-ring 22. The steering seal seat 15 is installed on the well 19 by bolts, and is sealed with the well 19 by an O-ring 1. There are 6 lip seals inside the steering seal, with #5, #6, #8 and #10 seals facing outwards, and #7 and #9 seals facing inwards. When used for the first time, the #5 / #6 and #6 / #7 sealing chambers are filled with grease.

[0048] Input shaft seal: The input shaft sealing system prevents lubricating oil from entering the propeller compartment. Since the sealing line speed at the input shaft is relatively high, a sealing ring made of FKM material should be used. Figure 5 The input shaft seal structure is shown. The input shaft seal structure consists of an input shaft seal bushing 28, a pipe joint 1, a spacer 31, two sets of lip seals 32, a locking nut 33, an O-ring 2, a dust ring 35, a pressure plate 36, an input shaft seal seat 37 and a pipe joint 2. The lip seal 32 is divided into two layers, #11 and #12, with the lips facing the inside of the full-rotation propeller. The middle chamber of the #11 / #12 seal ring is connected to the input shaft seal oil tank G and the input shaft seal lubricating oil pump unit H. Since the input shaft seal oil tank is located about 2m above the seal ring, it can offset the pressure inside the full-rotation propeller on the #11 seal ring, reduce the wear of the #11 seal ring lip and the input shaft seal bushing, and change the traditional single-pass seal ring to a double-pass seal ring, which enhances the sealing performance and reduces the risk of leakage. At the same time, the input shaft seal lubricating oil pump unit H can flush and filter out impurities in the chamber of the #11 / #12 sealing ring, effectively improving the operating conditions of the sealing rings #11 and #12, and can effectively improve the sealing effect of the sealing rings and extend their service life.

[0049] Air control unit: air source interface AP1 is connected to filter F1 and filter F2, the air inlet end of filter F1 is connected to valve V1, the air outlet end of filter F2 is connected to valve V2, air source interface AP1 is connected to pressure gauge P1 through valve V10 and valve V3; valve V2 is connected to conversion switch C1, conversion switch C1 is connected to flow meter FM1 through pressure reducing valve R1 and then to air flow controller FC1; conversion switch C1 is connected to flow meter FM2 through pressure reducing valve R2 and then to air flow controller FC2; air flow controller FC1 and air flow controller FC2 is connected to shuttle valve S1 (interfaces on both sides, whichever side has higher pressure, the gas flows to the middle channel); clean fresh water is connected to the three-way stopcock through valve V9, and shuttle valve S1 is connected to pressure switch A1 (when the pressure is lower than the threshold, an alarm signal is sent to the PLC control) and pressure gauge P1 through valve V5 and valve V6 respectively. Shuttle valve S1 is connected to one end of conversion switch C2 through valve V8, and the other end of conversion switch C2 is connected to shuttle valve S2 and air relay AR1 respectively. S2 is connected to pressure gauge P5 through valve V12, and shuttle valve S2 is also connected to valve V11. Relief valve V7 and relief valve V13 are connected to shuttle valve S1 and shuttle valve S2 respectively. like Figure 6 The following is a schematic diagram of the air control unit. Its main functions are as follows: Filter the air from the shipyard: The air source of the air control unit is marine air above 0.4MPa, and its cleanliness cannot meet the use requirements of the propeller shaft seal. The marine air passes through two filters, F1 and F2, to filter out moisture and other impurities in the air. The differential pressure indicator DP1 is used to indicate the pressure difference before and after the filter. If the pressure difference exceeds the preset value (the pressure difference setting value is generally 0.1MPa), an alarm indication will be issued. At this time, the air filters F1 and F2 need to be cleaned. The cleaning steps are: open the V10 valve, close the V1 and V2 valves, open the V3 valve to release the pressure in the air filter and then close it, remove the filter element of the air filter and clean it with high-pressure air or fresh water. If it still cannot meet the use requirements after cleaning, the filter element should be replaced; after repair, reinstall the filter element, open the V1 and V2 valves, and close the V10 valve. When cleaning the air filter element, it will not affect the operation of the air sealing system.

[0050] Adjust the air pressure: The air pressure entering the steering rudder seal, propeller shaft seal, propeller shaft seal oil tank, and full-turn rudder propeller seal oil tank can be controlled by adjusting the pressure reducing valves R1 and R2. The specific adjustment pressure range is determined according to the actual working conditions. If the pressure reducing valve R1 fails, the conversion switch C1 should be adjusted to the standby position and the pressure reducing valve R2 should be enabled to start working.

[0051] Adjust the air flow: The air flow entering the sealing system can be adjusted to a reasonable range through the air flow controllers FC1 and FC2. The real-time flow can be observed through the flow meters FM1 and FM2. If the use requirements cannot be met, the conversion switch C1 can be adjusted to the standby position and the air flow controller FC2 can be enabled to start working.

[0052] Provide air for the rudder seal, propeller shaft seal, propeller shaft seal oil tank and full-turn rudder propeller seal oil tank: the air control unit provides filtered and reduced-pressure air to the annular cavity of the #2 / #3 seal ring of the propeller shaft seal, the annular cavity of the #6 / #7 seal ring and the annular cavity of the #8 / #9 seal ring of the rudder seal, the propeller shaft seal oil tank and the full-turn rudder propeller seal oil tank.

[0053] Stability of control system pressure: Air relay AR1 is used to control the pressure supplied to the propeller shaft sealing oil tank and the full-turn rudder propeller sealing oil tank to be higher than the pressure supplied to the annular cavity of the #2 / #3 sealing ring of the propeller shaft seal, the annular cavity of the #6 / #7 sealing ring of the rudder seal, and the pressure of the discharge unit. If a fault occurs, the conversion switch C2 should be adjusted to the standby position to allow air to be delivered to the propeller shaft sealing oil tank and the full-turn rudder propeller sealing oil tank from the pipeline behind the flow controller.

[0054] Provide clean fresh water for cleaning air pipelines: V9 provides the system with fresh water for cleaning air pipelines. When the pressure difference between the output pressure P4 of the air control unit and the pressure P8 of the discharge unit exceeds the specified value, the three-way stopcock needs to be adjusted to the fresh water pipeline and the pipeline needs to be flushed with fresh water. The air pipeline can also be cleaned regularly.

[0055] Propeller shaft seal oil tank: like Figure 7 The diagram shows the principle diagram of the propeller shaft seal oil tank. The main functions of the propeller shaft seal oil tank are: to provide lubricating oil for the propeller shaft seal lubricating oil pump unit; to provide a certain pressure for the ring cavity of the #7 / #8 seal ring and the ring cavity of the #9 / #10 seal ring of the steering seal, so that the oil pressure in the ring cavity of the #7 / #8 seal ring and the ring cavity of the #9 / #10 seal ring is higher than the air pressure in the ring cavity of the #6 / #7 seal ring and the ring cavity of the #8 / #9 seal ring within the range of 0.05MPa, which reduces the pressure on the #7, #8, and #9 seal rings, improves their sealing performance, and prolongs their service life; to provide a certain pressure for the ring cavity of the #3 / #4 seal ring of the propeller shaft seal, so that its oil pressure is higher than the air pressure in the ring cavity of the #2 / #3 seal ring within the range of 0.05MPa, which greatly increases the service life of the #3 seal ring.

[0056] The propeller shaft sealing oil tank is also equipped with a safety valve SV1, a high air pressure alarm switch A2, a low air pressure alarm switch A3, and a high and low oil level alarm switch A4, which can avoid damage to the sealing system due to excessive pressure, and can promptly detect high or low liquid levels, eliminate hidden dangers in a timely manner, improve the reliability of the full-revolving rudder propeller sealing operation, and ensure the safety of ship operation.

[0057] Propeller shaft seal oil pump unit: like Figure 8 The diagram shows the principle diagram of the propeller shaft seal lubricating oil pump unit. The main functions of the propeller shaft seal lubricating oil pump unit are to filter out impurities in the oil entering the annular cavity of the steering seal and propeller shaft seal ring; the cooler is usually connected to 36°C fresh water, which plays a cooling role when the lubricating oil temperature is high, and can heat the oil temperature when the seawater temperature is very low.

[0058] The propeller shaft seal lubricating oil pump unit is mainly composed of motors M1 and M2, pumps PU1 and PU2, pressure sensor A5, pressure gauge P6, duplex filters F3 and F4, and lubricating oil cooler. Pumps PU1 and PU2 are used in one and standby. When the pressure sensor A5 is lower than the set value, the standby pump PU2 is activated and will not affect the operation of the system. The cooler is connected in parallel with a one-way valve D9. When the cooler is blocked, the oil will enter the full-turn propeller through the one-way valve D9. At this time, close the ball valves V22 and V23 and remove the cooler for maintenance. The duplex filter is equipped with one-way valves D10 and D11 and a pressure differential transmitter A6. When the filter F3 is blocked, the pressure differential transmitter A6 sends an alarm signal, the one-way valve D10 opens, and the oil flows from the one-way valve D10 to the rear pipeline. At this time, the handle of the duplex filter should be switched to the other side, the filter F4 should be activated, and the filter element of the filter F3 should be removed for cleaning or replacement.

[0059] Input shaft seal oil tank: like Fig. 9 The figure shows the schematic diagram of the input shaft seal oil tank. The main functions of the input shaft seal oil tank are: to provide lubricating oil for the input shaft seal oil pump unit; to provide a certain pressure for the annular cavity of the #11 / #12 seal ring of the input shaft seal, to offset part of the pressure inside the full-rotation propeller on the #11 seal ring, to reduce the wear of the #11 seal ring and the input shaft bushing, to enhance its sealing performance and extend its service life. The input shaft seal oil tank is also equipped with an oil level high and low alarm switch A7. When the input shaft #11 seal ring is damaged, the high liquid level switch alarms, and when the input shaft #12 seal ring is damaged, the low liquid level switch alarms, which can timely discover and eliminate the hidden dangers of oil leakage to ensure navigation safety.

[0060] Input shaft seal oil pump unit: like Fig.10The figure shows the principle diagram of the input shaft seal lubricating oil pump unit. The main functions of the input shaft seal lubricating oil pump unit are: filtering out impurities in the oil entering the ring cavity of the #11 / #12 seal ring of the input shaft seal; circulating the oil entering the input shaft seal ring, and reducing the operating temperature of the input shaft seal ring through natural heat dissipation.

[0061] The input shaft seal lubricating oil pump unit is mainly composed of motors M3 and M4, pumps PU3 and PU4, pressure gauge P7, pressure sensor A8 and filter F5. The filter is equipped with a one-way valve D12 and a differential pressure transmitter A9. When the filter F5 is blocked, the differential pressure transmitter A9 sends an alarm signal, the pressure continues to rise, the one-way valve D12 opens, and the oil flows from the one-way valve D12 to the chamber of the input shaft seal ring; pumps PU3 and PU4 are one for use and one for backup. When the pressure sensor A8 is lower than the set value, the backup pump PU4 is enabled, which will not affect the operation of the system. If both pumps PU3 and PU4 cannot operate, the ball valve V30 can be opened manually, and the oil in the input shaft seal oil tank acts on the chamber of the #11 / #12 seal ring of the input shaft seal under the action of gravity, which can still offset part of the pressure acting on the seal ring #11 from the full-turn propeller seal oil tank, ensuring the normal operation of the system.

[0062] Sealed oil tank for azimuth propeller: like Fig.11 The diagram shows the principle diagram of the full-revolving propeller sealing oil tank. The main functions of the full-revolving propeller sealing oil tank are: to offset part of the pressure of the propeller shaft sealing oil tank on the #10 sealing ring for the rudder seal, and to control the pressure difference of the #10 sealing ring within the range of 0.05MPa through the action of the flow limiter, thereby enhancing its sealing effect and extending its service life; to offset part of the pressure of the propeller shaft sealing oil tank on the #4 sealing ring for the propeller shaft seal, and to control the pressure difference of the #4 sealing ring within the range of 0.05MPa through the action of the flow limiter, thereby enhancing its sealing effect and extending its service life; once the propeller shaft seal or the rudder seal fails, the pressure of the full-revolving propeller sealing oil tank is higher than the seawater pressure, which can prevent seawater from flowing back into the rudder propeller.

[0063] The fully rotating propeller sealing oil tank is also equipped with a safety valve SV2, an air pressure high alarm switch A10, an air pressure low alarm switch A11, and an oil level high and low alarm switch A12, thereby avoiding damage to the sealing system due to excessive pressure, and being able to promptly detect high or low liquid levels, eliminate hidden dangers in a timely manner, improve the reliability of the fully rotating propeller sealing operation, and ensure the safety of ship operation.

[0064] Drain collection unit: like Fig.12 The main functions of the bleed collection unit are: Collect the oil and seawater leaked from the chambers of the propeller shaft seal #2 / #3 seal rings and the chambers of the steering rudder seal #6 / #7 seal rings; Used to monitor the operating status of the propeller shaft seal and the rudder seal: The flow controller installed in the discharge collection unit is used to monitor the air flow in the discharge pipeline and ensure that the discharge pipeline is unobstructed. When seawater enters or lubricating oil leaks, it will be collected in the unit through the discharge pipeline and a high-level alarm will be issued to remind the engine management personnel that the propeller shaft seal or the rudder seal is in abnormal working condition. The engine personnel should drain the oil and water in the discharge collection cabinet when the main engine is stopped.

[0065] Collect water for cleaning the air pipeline: open the discharge valve V39 of the discharge collection unit, switch the three-way stopcock of the air control unit to the fresh water pipeline, open the fresh water valve V9, and flush the pipeline with clean fresh water until the water flows out of the discharge valve V39 on the discharge collection unit. After cleaning, switch the three-way stopcock to the air pipeline side and close the discharge valve V39. Flushing can only be done when the main engine is stopped.

[0066] The above-mentioned fully rotating propeller air sealing system forms all the seals of the fully rotating propeller system into a whole by adding a propeller shaft sealing oil tank, a propeller shaft sealing lubricating oil pump unit, an input shaft sealing oil tank, and an input shaft sealing lubricating oil pump unit, so that the pressure on each seal can be controlled below 0.05MPa, which can effectively improve the sealing effect of the sealing ring and extend its service life.

[0067] The input shaft seal oil tank and input shaft seal lubricating oil pump unit were introduced, and the traditional single-pass seal structure was changed to a double-pass seal structure. Both seals are oil lubricated, and the oil can circulate, which has the effect of heat dissipation and cooling, improving the operating conditions of the input shaft seal ring. High and low liquid level sensors were introduced, so that once a leak occurs, the fault can be discovered and eliminated in time.

[0068] A flow restrictor is added in front of the fully rotating propeller sealing oil tank to reduce the pressure on the input shaft #11 seal ring, making it unnecessary to use a high-pressure resistant seal, reducing procurement costs, and enabling the entire fully rotating propeller to adapt to working conditions with deeper drafts, thereby increasing the scope of use of the fully rotating propeller.

[0069] A propeller shaft seal oil tank has been added, and the propeller shaft seal structure has been changed from 3 seals to 4 seals. Once the propeller shaft seal #3 fails, the oil in the propeller shaft seal will be contaminated first and the liquid level will be lowered, making it easier for engine management personnel to promptly discover and eliminate hidden dangers. The propeller shaft seal oil tank contains less oil and will not cause large-scale oil pollution, causing little damage to the environment. This avoids the previous 3-seal structure, which would cause large-scale water pollution once the #3 seal fails.

[0070] The air control unit has added a fresh water cleaning pipeline. Once the air pipeline is blocked, you only need to switch the three-way stopcock of the air control unit to the fresh water flushing pipeline when the main engine is shut down to clean the air pipelines of the propeller shaft seal and the rudder seal. There is no need to dock for maintenance, which shortens the maintenance cycle and greatly reduces the economic losses caused by maintenance and shutdowns.

[0071] The embodiments of the present disclosure have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or technical improvements in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. An air sealing system for a fully rotating propeller, characterized in that: The system includes: a propeller shaft seal, a steering rudder seal, an input shaft seal, an air control unit, a propeller shaft seal oil tank and a discharge collection unit, and the system also includes: a propeller shaft seal lubricating oil pump unit, an input shaft seal oil tank, an input shaft seal lubricating oil pump unit, and a full-turn propeller seal oil tank; The compressed air on board is filtered, decompressed and flow-regulated by the air control unit before entering the annular cavity of the #2 / #3 sealing ring of the propeller shaft seal and the annular cavity of the #6 / #7 sealing ring of the rudder seal. A part of the air overcomes the tension of the #1, #2 sealing rings and the #5, #6 sealing rings themselves and the pressure of the seawater and is released into the seawater in the form of bubbles. The other part of the air enters the discharge unit J from the pipeline and is discharged into the air. The compressed air on board enters the propeller shaft seal oil tank after being filtered, decompressed and flow-regulated by the air control unit. Then the propeller shaft seal lubricating oil pump unit transports the oil in the propeller shaft seal oil tank through the annular cavity of the #7 / #8 seal ring of the steering seal to the annular cavity of the #3 / #4 seal ring of the propeller shaft seal. Then the oil passes through the annular cavity of the #9 / #10 seal ring of the steering seal and returns to the propeller shaft seal oil tank. The compressed air on board is filtered by the air control unit, decompressed, and the flow is adjusted. The air is decompressed again by the flow restrictor, and then enters the full-rotation propeller sealing oil tank. The oil in the full-rotation propeller sealing oil tank is connected to the oil inside the propeller body. The lubricating oil in the #11 / #12 chamber of the input shaft seal is the circulating oil provided by the input shaft seal lubricating oil pump unit. There is a height difference between the input shaft seal oil tank and the input shaft seal, which can control the pressure of the #11 / #12 chamber of the input shaft seal to be lower than the pressure in the full-rotation propeller body, and the pressure difference is controlled within 0.05MPa.

2. The air sealing system for a fully rotating propeller according to claim 1, characterized in that: The structure of the propeller shaft sealing lubricating oil pump unit is as follows: the propeller shaft sealing lubricating oil pump unit includes: a double filter F3 and a filter F4, a motor M1 and a motor M2, a pressure sensor A5, a pressure gauge P6, a main pump PU1 and a standby pump PU2, and a first lubricating oil cooler; the main pump PU1 and the standby pump PU2 are connected in parallel; PU1 is the main pump and PU2 is the standby pump. When the pressure sensor A5 is lower than the set value, the standby pump PU2 is enabled. Motor M1 is used to drive the PU1 main pump, and motor M2 is used to drive the PU2 standby pump; The upstream and downstream of the PU1 main pump are connected in series with valve V18 and non-return valve D7 respectively; the upstream and downstream of the PU2 standby pump are connected in series with valve V19 and non-return valve D8 respectively; the upstream of the PU1 main pump is connected to the input shaft sealing oil tank; The downstream of the PU1 main pump is connected to the pressure gauge P6 through valve V21 and to the pressure differential transmitter through V20; The duplex filter F3 and filter F4 are equipped with one-way valve D10, one-way valve D11 and differential pressure transmitter A6. When the filter F3 is blocked, the differential pressure transmitter A6 sends out an alarm signal, the one-way valve D10 opens, and the oil flows from the one-way valve D10 to the pipeline behind. At this time, switch the handle of the duplex filter to the other side, activate the filter F4, and remove the filter element of the filter F3 for cleaning or replacement; The first lubricating oil cooler is connected to the downstream of the duplex filter F3 and the filter F4. A one-way valve D9 is connected in parallel to the first lubricating oil cooler. When the cooler is blocked, the oil will enter the full-turn propeller through the one-way valve D9. At this time, valves V22 and V23 are closed, and the cooler is removed for maintenance. WI1 and WO1 of the first lubricating oil cooler are respectively the first lubricating oil cooler water inlet and the first lubricating oil cooler water outlet.

3. The air sealing system for a fully rotating propeller according to claim 1, characterized in that: The input shaft seal oil tank includes valve 25 and valve 31. The input shaft seal oil pump unit is connected via valve 25 and the input shaft seal is connected via valve 31. The input shaft seal oil tank is also equipped with an oil level high and low alarm switch A7 and a drain valve V32. The functions of the input shaft seal oil tank include: providing lubricating oil to the input shaft seal lubricating oil pump unit, providing pressure to the annular cavity of the #11 / #12 seal ring of the input shaft seal, and offsetting part of the pressure inside the full-rotation propeller on the #11 seal ring.

4. The air sealing system for a fully rotating propeller according to claim 1, characterized in that: The input shaft seal lubricating oil pump unit includes: filter F5, motor M3 and motor M4, main pump PU3 and standby pump PU4, pressure gauge P7, pressure sensor A8; The filter F5 is equipped with a one-way valve D12 and a differential pressure transmitter A9. When the filter F5 is clogged, the differential pressure transmitter A9 sends out an alarm signal, the one-way valve D12 opens, and the oil flows from the one-way valve D12 into the chamber of the input shaft seal ring; The upstream of the main pump PU3 and the standby pump PU4 is connected to the input shaft sealing oil tank, and the downstream of the main pump PU3 and the standby pump PU4 is connected to the filter F5. The downstream of the main pump PU3 and the standby pump PU4 is also connected to the pressure difference transmitter A8 and the pressure gauge P7 through valve V29 and valve V28 respectively; The upstream of main pump PU3 is connected in series with valve V26 and the downstream is connected in series with check valve D13, and the upstream of standby pump PU4 is connected in series with valve V27 and the downstream is connected in series with check valve D14; Pump PU3 and pump PU4 are used as one for use and one for backup. When the pressure sensor A8 is lower than the set value, the backup pump PU4 is activated; The upstream of the pump PU3 and the downstream of the filter F5 are connected via a ball valve V30.

5. The fully rotating propeller air sealing system according to claim 1, characterized in that: Fully rotating propeller sealed oil tank, including: safety valve SV2, high air pressure alarm switch A10, low air pressure alarm switch A11, high and low oil level alarm switch A12; The high air pressure alarm switch A10 and the low air pressure alarm switch A11 are connected to the oil tank through valve V33 and valve V34 respectively, and the full-turn propeller sealing oil tank discharges lubricating oil through the normally closed ball valve V35; The sealed oil tank of the azimuth steering propeller is connected to the air control unit through a flow restrictor, and the sealed oil tank of the azimuth steering propeller is input to the azimuth steering propeller through a valve 36 .

Images