Cooling and lubricating water system for ship tail shaft

Abstract

The utility model relates to the technical field of ships, in particular to a cooling and lubricating water system for a ship tail shaft. The system comprises a machine belt water pump, a main machine cooling heat exchanger, a gearbox cooling heat exchanger, a tail shaft pipe, a cooling water main pipe, an emergency compensation water tank water inlet pipe, an emergency compensation water tank, an emergency compensation water pipe, a residue discharging valve, a flow adjusting valve, a fresh water cooling water pipeline and a fresh water cabinet, one end of the emergency compensation water pipe is connected to the bottom of the emergency compensation water tank, the other end of the emergency compensation water pipe is connected to the upper portion of the emergency compensation water tank and used for feeding cooling water into the emergency compensation water tank, and one end of the emergency compensation water pipe is connected to the bottom of the emergency compensation water tank while the other end of the emergency compensation water pipe is communicated with a tail shaft pipe; and the other end is connected to the fresh water tank on the ship. The system has a multi-path water supply function, multiple insurance is added to a stern shaft sealing assembly, and it is ensured that dry friction does not occur between stern shaft sealing pieces.

Description

Technical Field

[0001] The utility model relates to the technical field of ships, in particular to a cooling and lubricating water system for a ship's stern shaft. Background Art

[0002] The statements in this section are merely intended to provide background information related to the technical solution of the present application to aid understanding, and they do not necessarily constitute prior art with respect to the technical solution of the present application.

[0003] A ship's stern shaft is a crucial component for transmitting the ship's main engine power and enabling the ship's "main engine-propeller" coordination. It also serves to prevent the ingress of seawater into the engine room. During operation, the stern shaft operates in a harsh environment, subject to high temperatures, friction, wear, mechanical corrosion, and sudden loads. Therefore, the stern shaft seal assembly requires adequate cooling and lubrication. The cooling and lubrication medium used is categorized into two types: oil-lubricated stern shaft seals and water-lubricated stern shaft seals. Oil-lubricated stern shaft seals are primarily used on large vessels, while water-lubricated stern shaft seals are primarily used on small and medium-sized vessels. Regardless of the cooling and lubricating medium used, an adequate supply of cooling and lubricating medium is essential. Insufficient cooling and lubricating medium can lead to overheating within the stern shaft seal assembly, causing dry friction and damage to the stern shaft seal assembly, compromising the sealing effect and potentially causing water leakage from the engine room through the stern shaft, allowing seawater to enter the engine room.

[0004] A small ship engine room cooling and lubrication water system layout is as follows Figure 1 As shown. When the ship is started, the engine room staff opens the subsea valve in advance to start the main engine. Once the main engine is running, the main engine's seawater pump operates. Under the vacuum suction of the engine-driven seawater pump, cooling seawater passes through the subsea valve, reaches the main engine, and enters the main engine's seawater-fresh water cooling heat exchanger to complete the main engine cooling. After cooling the main engine, the seawater is split into two paths: one is discharged overboard, and the other enters the gearbox's seawater-fresh water cooling heat exchanger to complete the gearbox cooling. Thereafter, the seawater is split into two paths: one is discharged overboard, and the other is piped to the ship's stern shaft, providing cooling and lubrication water for the stern shaft seal assembly.

[0005] The cooling and lubricating water supply for the aforementioned ship's stern shaft seal assembly is limited to a single source, and it can only be obtained in a fixed sequence: "submarine gate - main engine - gearbox - stern shaft." This water supply line is long, passes through numerous devices, and contains numerous branches and valves. Any blockage, leak, or insufficient vacuum pressure at any point in the water supply line can lead to insufficient or even complete loss of cooling and lubricating water for the stern shaft, causing dry friction between the dynamic and static rings of the stern shaft seal, a sudden increase in the seal temperature, and stern shaft seal leakage. Furthermore, these failures are difficult to prevent and detect, resulting in sudden stern shaft leakage failures, which do not follow the failure probability curve or conform to the typical failure probability cycle. The dry friction between the dynamic and static rings within the stern shaft seal assembly before a stern shaft leakage failure occurs is difficult to detect in advance. Even if the failure is detected through temperature rise or sudden pressure changes, the ship's engineering crew cannot perform repairs while the stern shaft is rotating at high speed, making it difficult to interrupt the failure's progression and often forcing the ship to slow down or return to port. Utility Model Content

[0006] In order to solve the above problems, the present application proposes a cooling and lubricating water system for the stern shaft of a ship, which includes: an engine water pump, a main engine cooling heat exchanger for cooling and lubricating the main engine, a gear box cooling heat exchanger for cooling and lubricating the gear box, a tail shaft pipe, a cooling water main pipe, an emergency compensation water tank inlet pipe, an emergency compensation water tank, an emergency compensation water pipe, a residual valve, a flow regulating valve, a fresh water cooling water pipeline, and a fresh water tank, wherein the engine water pump is connected to the cooling water main pipe and is used to suck cooling water from the bottom of the ship into the cooling water main pipe, and the cooling water main pipe is connected to the main engine cooling heat exchanger, the gear box cooling heat exchanger, and the tail shaft pipe respectively through different connecting branches. The gear box cooling heat exchanger is connected to the tail shaft pipe through a pipeline, the tail shaft pipe is connected to the stern shaft of the ship, one end of the emergency compensation water tank inlet pipe is connected to the cooling water main pipe, and the other end is connected to the upper part of the emergency compensation water tank, which is used to send cooling water into the emergency compensation water tank. The drain valve is located at the bottom of the emergency compensation water tank, one end of the emergency compensation water pipe is connected to the bottom of the emergency compensation water tank, and the other end is connected to the tail shaft pipe. The flow regulating valve is provided in the emergency compensation water pipe, one end of the fresh water cooling water pipeline is connected to the upper part of the emergency compensation water tank, and the other end is connected to the fresh water tank on the ship, and a valve is provided in the fresh water cooling water pipeline.

[0007] In one embodiment, the cooling and lubricating water system for the ship's stern shaft further includes a liquid level detector installed inside the emergency compensation water tank and a liquid level sound and light alarm installed on the emergency compensation water tank.

[0008] In one embodiment, the flow regulating valve is a valve with an automatic opening function in case of pressure loss.

[0009] In one embodiment, the cooling and lubricating water system for the ship's stern shaft further includes an automatic air release valve installed on the upper part of the emergency compensation water tank.

[0010] In one embodiment, the fresh water tank is a pressure water tank on a ship.

[0011] In one embodiment, a valve is provided between the cooling water main pipe and the emergency compensation water tank inlet pipe.

[0012] In one embodiment, valves are provided in the connecting branches between the cooling water main pipe and the main engine cooling heat exchanger, the gearbox cooling heat exchanger, and the tail tube.

[0013] In one embodiment, the other end of the emergency compensation water pipe is connected to a connecting branch pipe between the cooling water main pipe and the tail tube, and is thereby indirectly connected to the tail tube.

[0014] In one embodiment, the other end of the emergency compensation water pipe is directly connected to the stern tube.

[0015] The beneficial effects of the cooling and lubricating water system for a ship's stern shaft of the present application are as follows:

[0016] (1) Multi-way water supply, multiple insurances. The system has a multi-way water supply function, which adds multiple insurances to the stern shaft sealing assembly. When the submarine door is normally available and not blocked, seawater can be used to lubricate and cool the sealing device of the stern shaft under normal working conditions, and there is no need to provide cooling and lubricating water to the stern shaft through a fixed sequence of "submarine door-main engine-gearbox-stern shaft". When there is insufficient seawater and the main engine water pump cannot pump enough seawater, the water in the emergency compensation water tank can be used for cooling and lubrication. If the water in the emergency compensation water tank is insufficient, the fresh water cooling water pipeline can be opened, and the water in the fresh water tank (such as the pressure water tank) can be used to temporarily cool and lubricate the stern shaft to ensure that there is no dry friction between the stern shaft seals.

[0017] (2) Water storage and emergency water replenishment. The emergency compensation water tank can store water when not in use and release water when needed. When the main engine is operating normally, the cooling water pipeline is not blocked or leaking, and the stern shaft is lubricated normally, the pipeline valve entering the emergency compensation water tank can be opened and the valve on the emergency compensation water pipe can be closed to ensure that seawater only enters but does not exit the emergency compensation water tank, thereby filling the emergency compensation water tank with seawater. After the water is filled, close the water tank inlet valve to make the water tank ready for use at any time.

[0018] (3) Automatic compensation and automatic alarm. The flow regulating valve on the emergency compensation water pipe is selected to have a valve with an automatic opening function due to pressure loss. When the stern shaft is not lubricated enough (insufficient water in the tail shaft tube), it can automatically replenish water and issue an alarm. Specifically, when the emergency compensation water tank is full of water, if the normal lubrication of the stern shaft is insufficient, the stern shaft lubrication water pressure will drop rapidly. The flow regulating valve of the emergency compensation water pipe will automatically open due to pressure loss and automatically replenish water to the stern shaft. At the same time, due to the decrease in the liquid level in the emergency compensation water tank, the liquid level sound and light alarm will sound an alarm, reminding the crew on duty that there is a problem with the normal lubrication of the stern shaft.

[0019] (4) Easy maintenance, can be stopped at any time. Open the inlet valve of the emergency compensation water tank and close the outlet valve to fill the emergency compensation water tank with water. Open the outlet valve to replenish water to the stern shaft. If the inlet valve and outlet valve of the emergency compensation water tank are closed at the same time, the emergency compensation system is not in use and can be maintained and repaired.

[0020] (5) Improve the navigation capability of small ships in floating ice conditions. After installing the cooling water emergency compensation system, the situation in which broken ice blocks the seabed door during winter navigation, causing poor lubrication of the stern shaft, will be greatly improved. Using the emergency compensation system, even if sea ice blocks the ship's seabed door, the "pressure water tank-stern shaft" fresh water cooling path can be used to ensure that dry friction of the stern shaft seal assembly does not occur.

[0021] (6) Extend the ship repair cycle and reduce ship repair costs. The stern shaft assembly is often a vulnerable part of the entire ship. Once the stern shaft assembly has problems such as leakage, the maintenance work is large and the shaft needs to be pulled out for major repairs or even docked ashore for repairs, resulting in increased ship repair costs and long ship downtime. After the stern shaft cooling water emergency compensation system is applied, the source of the fault, insufficient lubrication and cooling of the stern shaft seal assembly, can be eliminated in the bud, and the stern shaft seal assembly, a vulnerable part, will no longer be vulnerable. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The following further describes the embodiments of the present invention with reference to the accompanying drawings, wherein:

[0023] Figure 1 The diagram shows the arrangement of a cooling and lubricating water system for a small ship's engine room;

[0024] Figure 2 A cooling and lubricating water system for a stern shaft of a ship according to one embodiment of the present application is shown. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below through specific embodiments in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0026] Figure 2 A cooling and lubricating water system for a ship's stern shaft according to an embodiment of the present application is shown, which includes: a drive water pump 2, a main engine cooling heat exchanger 1 for cooling and lubricating the main engine 3, a gear box cooling heat exchanger 5 for cooling and lubricating the gear box 4, a stern shaft tube 10, a cooling water main pipe 14, an emergency compensation water tank inlet pipe 15, an emergency compensation water tank 18, an emergency compensation water pipe 16, a drain valve 19, and a flow regulating valve 22.

[0027] The engine water pump 2 is connected to the cooling water main 14. After the ship's main engine is started, the engine water pump 2 operates, and under the vacuum suction of the engine water pump 2, cooling and lubricating water (e.g., seawater) is drawn from the bottom of the ship into the cooling water main 14. The cooling water main 14 is connected to the main engine cooling heat exchanger 1, the gearbox cooling heat exchanger 5, and the stern tube 10 through separate connecting branches, delivering cooling water to each of these three systems. The main engine cooling heat exchanger 1 cools the main engine 3, and the gearbox cooling heat exchanger 5 cools the gearbox 4. The gearbox cooling heat exchanger 5 is connected to the stern tube 10 via a pipeline. The stern tube 10 is connected to the ship's stern shaft.

[0028] The emergency compensation water tank 18 is a water storage device. One end of the emergency compensation water tank inlet pipe 15 is connected to the cooling water main 14, and the other end is connected to the upper part of the emergency compensation water tank 18, which is used to send cooling water into the emergency compensation water tank 18 for storage. The residual valve 19 is located at the bottom of the emergency compensation water tank 18 and is used to release the residual water in the emergency compensation water tank 18 when needed. One end of the emergency compensation water pipe 16 is connected to the bottom of the emergency compensation water tank 18, and the other end is connected to the stern shaft tube 10. A flow control valve 22 is provided in the emergency compensation water pipe 16 to adjust and control the cooling water flow so that the cooling water in the emergency compensation water tank 18 can enter the ship's stern shaft to play a cooling and lubricating role.

[0029] In one embodiment, the other end of the emergency compensation water pipe 16 is connected to the connecting branch pipe between the cooling water main 14 and the tail tube 10, and is thereby indirectly connected to the tail tube 10. In one embodiment, the other end of the emergency compensation water pipe 16 is directly connected to the tail tube 10.

[0030] In one embodiment, the cooling and lubricating water system for the ship's stern shaft also includes a freshwater cooling water pipeline (not shown in the figure) connected to the upper part of the emergency compensation water tank 18, the other end of which is connected to a freshwater tank on the ship, such as a pressure water tank. A valve is provided in the freshwater cooling water pipeline. When needed, fresh water in the freshwater tank can be sent to the emergency compensation water tank 18 through the freshwater cooling water pipeline, and then finally enter the ship's stern shaft through the emergency compensation water pipe 16 to achieve cooling and lubrication, forming a new freshwater cooling and lubrication path of "freshwater tank-ship stern shaft". This is quite necessary under certain fault conditions (for example, when the engine water pump 2 fails and the stored water in the emergency compensation water tank 18 is used up).

[0031] In one embodiment, the cooling and lubricating water system for the stern shaft of a ship further includes a liquid level detector (not shown) installed inside the emergency compensation water tank 18, and a liquid level sound and light alarm 20 installed on the emergency compensation water tank 18. When the liquid level detector detects an abnormal liquid level, the liquid level sound and light alarm 20 can sound an alarm in the form of sound and light.

[0032] In one embodiment, the flow regulating valve 22 in the emergency compensation water pipe 16 is a valve with an automatic opening function due to pressure loss. In this way, if the normal lubrication of the stern shaft is insufficient, the water in the tail shaft tube 10 will decrease rapidly, and the pressure in the emergency compensation water pipe 16 will decrease, causing the flow regulating valve 22 to automatically open due to pressure loss and automatically replenish water to the stern shaft. At the same time, due to the decrease in the liquid level in the emergency compensation water tank 18, the liquid level sound and light alarm 20 will emit an sound and light alarm, reminding the crew on duty that there is a problem with the normal lubrication of the stern shaft.

[0033] In one embodiment, the cooling and lubricating water system for the stern shaft of a ship further includes an automatic air release valve 21 installed on the upper portion of the emergency compensation water tank 18 .

[0034] In one embodiment, a valve is provided between the cooling water main 14 and the emergency compensation water tank inlet pipe 15. In one embodiment, valves are provided in the connecting branches between the cooling water main 14 and the main engine cooling heat exchanger 1, the gearbox cooling heat exchanger 5, and the stern tube 10.

[0035] References herein to "various embodiments," "some embodiments," "one embodiment," or "an embodiment," etc., mean that a particular feature, structure, or property described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the phrases "in various embodiments," "in some embodiments," "in one embodiment," or "in an embodiment," etc., in various places throughout this document do not necessarily refer to the same embodiment. Furthermore, particular features, structures, or properties may be combined in any suitable manner in one or more embodiments. Thus, particular features, structures, or properties shown or described in connection with one embodiment may be combined, in whole or in part, with features, structures, or properties of one or more other embodiments without restriction, as long as the combination is not illogical or inoperable.

[0036] Some exemplary embodiments of the present invention are described above. It will be understood that the above embodiments are only used to explain the present invention and do not constitute a limitation on the scope of protection of the present invention. The features in these embodiments can be recombined in an appropriate manner, and the solutions obtained thereby are still within the scope of protection claimed by the present invention. Based on the above embodiments, all other embodiments obtained by those skilled in the art without making any creative work, that is, all modifications, equivalent substitutions and improvements made within the spirit and principles of this application, fall within the scope of protection claimed by the present invention.

Claims

1. A cooling and lubricating water system for a ship's stern shaft, characterized in that: include: A machine-driven water pump (2), a main engine cooling heat exchanger (1) for cooling and lubricating a main engine (3), a gear box cooling heat exchanger (5) for cooling and lubricating a gear box (4), a stern tube (10), a cooling water main pipe (14), an emergency compensation water tank inlet pipe (15), an emergency compensation water tank (18), an emergency compensation water pipe (16), a residual valve (19), a flow regulating valve (22), a fresh water cooling water pipeline, and a fresh water tank, wherein the machine-driven water pump (2) is connected to the cooling water main pipe (14) and is used to draw cooling water from the bottom of the ship into the cooling water main pipe (14), the cooling water main pipe (14) is connected to the main engine cooling heat exchanger (1), the gear box cooling heat exchanger (5), and the stern tube (10) respectively through different connecting branches, and the gear box cooling heat exchanger ( 5) is connected to the tail shaft pipe (10) through a pipeline, the tail shaft pipe (10) is connected to the stern shaft of the ship, one end of the emergency compensation water tank inlet pipe (15) is connected to the cooling water main pipe (14), and the other end is connected to the upper part of the emergency compensation water tank (18), for sending cooling water into the emergency compensation water tank (18), the residual valve (19) is located at the bottom of the emergency compensation water tank (18), one end of the emergency compensation water pipe (16) is connected to the bottom of the emergency compensation water tank (18), and the other end is connected to the tail shaft pipe (10), the flow regulating valve (22) is provided in the emergency compensation water pipe (16), one end of the fresh water cooling water pipeline is connected to the upper part of the emergency compensation water tank (18), and the other end is connected to the fresh water tank on the ship, and a valve is provided in the fresh water cooling water pipeline.

2. The cooling and lubricating water system for a ship's stern shaft according to claim 1, wherein: It also includes a liquid level detector installed inside the emergency compensation water tank (18) and a liquid level sound and light alarm (20) installed on the emergency compensation water tank (18).

3. The cooling and lubricating water system for a ship's stern shaft according to claim 1, wherein: The flow regulating valve (22) is a valve with a function of automatically opening in case of pressure loss.

4. The cooling and lubricating water system for a ship's stern shaft according to claim 1, wherein: It also includes an automatic air release valve (21) installed on the upper part of the emergency compensation water tank (18).

5. The cooling and lubricating water system for a ship's stern shaft according to claim 1, wherein: The fresh water tank is a pressure water tank on a ship.

6. The cooling and lubricating water system for a ship's stern shaft according to claim 1, wherein: A valve is provided between the cooling water main (14) and the emergency compensation water tank inlet pipe (15).

7. The cooling and lubricating water system for a ship's stern shaft according to claim 1, wherein: Valves are provided in the connecting branches between the cooling water main pipe (14) and the main engine cooling heat exchanger (1), the gear box cooling heat exchanger (5), and the tail shaft pipe (10).

8. The cooling and lubricating water system for a ship's stern shaft according to claim 1, wherein: The other end of the emergency compensation water pipe (16) is connected to a connecting branch pipe between the cooling water main pipe (14) and the tail tube (10), and is thereby indirectly connected to the tail tube (10).

9. The cooling and lubricating water system for a ship's stern shaft according to claim 1, wherein: The other end of the emergency compensation water pipe (16) is directly connected to the stern tube (10).

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