JPH0710084A - Stern tube shaft sealing device - Google Patents

Abstract

PURPOSE:To surely prevent the deterioration and abnormal abrasion of a sealing material due to the sliding heat even in the severe working conditions of large draft and high peripheral velocity by realizing the sliding of an end-face type seal with the seal casing rotating with the propeller shaft, and the contact of the outer circumferential surface of this seal casing with sea water. CONSTITUTION:The leakage of the lubrication oil sealed in a setting part of a tip type seal is prevented by pressing inner side sliding surfaces 61, 71 of end-face type seals 6, 7 against the vertical sliding surface of a seal casing 4 by the flushing water supplied to the respective pressure chambers 63, 73 of the end-face type seals 6, 7 to realize the sealing action by the end-face type seals 6, 7. The sliding heat of the end-face type seals is radiated into sea water by the flushing water passing through the respective end-face type seals 6, 7, preventing the deterioration and abnormal abrasion of the sealing material by the sliding heat.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shaft seal device for a propeller shaft in a stern tube of a ship, and more particularly, it is mounted on the stern side of a stern tube to seal between seawater and lubricating oil on the outer periphery of the propeller shaft. The present invention relates to a stern tube shaft sealing device.

[0002]

2. Description of the Related Art Conventionally, a stern tube shaft sealing device as shown in FIG. 4 has been proposed. That is, in FIG. 4, reference numerals 114 and 115 indicate stern tube bearings mounted on the hull 116 for supporting the propeller shaft 113. Since the stern tube bearings 114 and 115 use lubricating oil, Oil 117
In order to prevent the stern tube bearings 114 and 115 from leaking to the outside, stern tube shaft sealing devices are provided at two positions on the bow side and the stern side of the stern tube bearings 114 and 115.
The stern tube shaft sealing device has inner diameter end portions on the inner circumference of casings 100 and 109 of the shaft sealing device which are provided at the front end portion and the rear end portion of the hull 116 so as to surround the outer circumference of the propeller shaft 113. It is provided with rubber lip type seals 101 to 104 and 110 to 111 which are in sliding contact with the outer peripheral surfaces of the liners 105 and 112 of the propeller shaft 113, and lubricating oil is provided between the lip type seals to lubricate the sliding portion. It is enclosed.

Many vessels are equipped with an emergency pipe 106 in order to ensure the durability of the lip-type seal of the stern shaft sealing device, which is relatively difficult to convert the lip-type seal. Further, the pipe 108 for draining the lubricating oil that lubricates the stern bearings 114, 115 is equipped with the valve 107, and by normally opening the valve 107, the lip type seal 103
The hydraulic pressure between stern 104 and stern tube bearing 114,1
This is the same as in the vicinity of 15, and as a result, the lip type seal 104 is set in the free state, and the lip type seal 103 is made to function. When there is an abnormality such as wear of the lip-type seal 103, the valve 107 can be closed by closing the valve 107.
The pressure between 104 and the lip seal 104 begins to work.

[0004]

By the way, in the conventional stern tube shaft sealing device as described above, the lip-type seal 101 located closest to the stern side and in contact with seawater is the seal liner 105.
Most of the sliding heat generated by sliding with is released into seawater, so it is cooled well, but since the other lip-type seal inside it does not contact seawater, the generated sliding heat is It is released through the lubricating oil inside the ship and the seal liners 105 and 112. However, the conventional stern tube shaft sealing device is generally an enclosed type in which lubricating oil is not circulated as shown in FIG. 4, and the amount of oil is limited even in the type in which lubricating oil is circulated. Therefore, there is a problem that a sufficient cooling effect cannot be expected. Further, since the seal liner 105 is generally made of a high-chromium steel material having excellent corrosion resistance and wear resistance and has a low thermal conductivity, heat radiation through the seal liner 105 is not sufficient.

Therefore, in the lip type seal liner,
Viton materials and the like, which have excellent heat resistance, are used, but considering wear resistance, that is, durability, changing the material alone is not always sufficient. Further, since a lubricating oil is enclosed or minutely circulated between the lip-type seals, there is a problem that a small amount of lubricating oil naturally flows out of the ship. Recently, from the viewpoint of preventing marine pollution, a leak-free type (polluting type) that replaces this lip-type seal for lubricating oil
The seal has been desired. The present invention is intended to solve such a problem, and an end face type seal is disposed on the stern side of the lip type seal, and flushing water is supplied to the end face type seal to perform a sealing action. At the same time, it is an object of the present invention to provide a stern tube shaft sealing device capable of releasing the sliding heat of the sliding portion into the sea by flushing water.

[0006]

In order to achieve the above-mentioned object, a stern tube shaft sealing device of the present invention comprises a propeller shaft, a stern tube bearing for rotatably supporting the propeller shaft with respect to a hull,
The seal casing includes a tubular seal casing attached to the rear end of the hull so as to surround the propeller shaft, and a seal liner attached to the propeller shaft and disposed inside the seal casing. A lip-type seal whose inner diameter end is slidably in contact with the seal liner is attached to the inner wall surface of the two, and two lip-shaped seals having a substantially L-shaped cross-section are formed on the stern side of the lip-type seal inside the seal casing. End face seals are attached to the seal liners with their respective horizontal planes and are arranged in the front-rear direction, and inner surfaces slidable with the vertical sliding faces of the seal casing are provided on the respective vertical faces of the end face seals. An outer sliding surface and a pressure chamber located between the outer sliding surfaces and opening toward the vertical sliding surface of the seal casing are respectively provided. It is formed, separately can be supplied flushing water passage are provided respectively in the pressure chambers, is characterized by flow control device of the flushing water in the respective passages are respectively attached.

[0007]

The above-described stern tube shaft sealing device of the present invention operates as follows. (1) Since the end face seal rotates with the propeller shaft, the heat generated on the outer sliding face and the inner slide face of the end face seal is easily released to seawater through the seal casing. (2) Since the two end face type seals can be switched and used by performing the following operation, the reliability of the shaft sealing device itself is significantly improved.

Normally, flushing water is supplied to the pressure chamber of the end face type seal on the bow side to make the end face type seal function. On the other hand, water is not passed through the stern-side end face seal, and flushing water that has cooled the bow-side end face-type seal flows in from the inside of the inner sliding surface of the stern-side end face-type seal. The sliding surface is free. This allows it to be used as a spare seal. When the end face type seal on the bow side is abnormal, water is not passed through the seal or a small amount of water is passed through. On the other hand, by supplying flushing water to the pressure chamber of the end face type seal on the stern side, the end face type seal starts to function.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A stern tube shaft sealing device as an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a side sectional view thereof, and FIG. 2 is an enlarged view of a portion "II" of FIG. FIG. 3 is a side sectional view showing the case where the abnormal state is dealt with. In FIG. 1, reference numeral 1 denotes a propeller shaft, and the propeller shaft 1 is rotatably supported on a hull 3 by a stern tube bearing 2. A cylindrical seal casing 4 is attached to the rear end of the hull 3 so as to surround the propeller shaft 1, and a seal liner 5 is attached to the propeller shaft 1 so as to be arranged inside the seal casing 4. ing.

On the inner wall surface of the seal casing 4, lip type seals 8 and 9 whose inner diameter ends are in sliding contact with the seal liner 5 are attached. Further, on the stern side of the lip type seals 8 and 9 inside the seal casing 4, two end face type seals 6 and 7 having a substantially L-shaped cross section are attached to the seal liner 5 with their respective horizontal planes. Are arranged in the front-back direction. On the vertical surfaces of the end face type seal liners 6 and 7, the vertical outer sliding surfaces 62 and 72 and the inner sliding surfaces 61, which slidably oppose the vertical sliding surfaces of the seal casing 4,
71 are formed respectively, and pressure chambers 63, 73 opening toward the vertical sliding surface of the seal casing 4 are formed between the outer sliding surfaces 62, 72 and the inner sliding surfaces 61, 71, respectively. (See FIGS. 2 and 3).

Reference numerals 15a and 15b denote cylindrical springs for pressing the end face type seals 6 and 7 toward the seal liner 5. Passages 10 and 11 for separately supplying the flushing water F to the pressure chambers 63 and 73 are formed through the hull 3 and the seal casing 4, and the flow control valves 13 for flushing water are provided in the passages 10 and 11, respectively. , 14 are installed.
Reference numeral 12 indicates a drain pipe.

In the above construction, the seal casing 4
The lip seals 8 and 9 are stationary, and the seal liner 5 and the end face seals 6 and 7 rotate together with the propeller shaft 1. Therefore, in the end face type seals 6 and 7, the seal casing and the inner sliding faces 61 and 71 and the outer sliding faces 62 and 72 are
However, in the lip-type seals 8 and 9, each inner diameter end portion becomes a sliding portion. In normal state, the end face type seals 6 and 7 are shown in FIG.
It is in the state shown in.

That is, the flushing water F having a pressure slightly higher than that of stuttering water is supplied to the pressure chamber 73 of the end face type seal 7 on the bow side.
Is supplied by the pressure of this flushing water and the inner sliding surface 71
Is pressed against the vertical sliding surface of the casing 4 to perform a sealing action. On the other hand, the outer sliding surface 72 is pushed open in a direction away from the vertical sliding surface on the casing 4 side, passes through the clearance, and the flushing water is guided to the end face type seal 6 on the stern side through the chamber 4b. Here, since the flushing water F is not supplied to the pressure chamber 63 of the end face type seal 6 on the stern side, a gap is generated between the inner and outer sliding surfaces 61 and 62 and the casing 4, and the chamber 4a is discharged from here. After that, it is discharged to the outside of the ship.

As a result, the end face type seal 7 on the bow side functions, and the end face type seal 6 on the stern side becomes free and exists as a preliminary seal. When a problem occurs in the end face type seal 7 on the bow side, the state is switched to the state shown in FIG. That is, the pressure chamber 63 of the end face type seal 6 on the stern side
The flushing water F is supplied only to. As a result, the inner sliding surface 61 of the end face type seal 6 functions, and the flushing water F is drained out of the ship through the chamber 4a from the clearance between the outer sliding surface 62 and the casing 4.

In this way, the flushing water supplied to the pressure chambers 63, 73 of the end face seals 6, 7 causes the inner sliding surfaces 61, 71 of the end face seals 6, 7 to seal the casing 4.
Of the lip type seals 8 and 7 by pressing against the vertical sliding surface of the
It is possible to prevent leakage of the lubricating oil sealed in the installation portion of 9. Further, the sliding heat of the end face type seals is radiated into the seawater by the flushing water passing through the respective end face type seals 6 and 7, so that it is possible to prevent deterioration and abnormal wear of the sealing material due to the sliding heat.

[0016]

As described in detail above, according to the stern tube shaft sealing device of the present invention, the following effects and advantages can be obtained. (1) The end face seal rotates with the propeller shaft and slides against the seal casing, and since the outer peripheral surface of this seal casing is in contact with seawater, it is cooled reliably, so that the sliding heat of the end face seal is absorbed. The heat can be easily and effectively dissipated into the seawater through. Therefore, it is possible to reliably prevent deterioration and abnormal wear of the sealing material due to sliding heat even under severe operating conditions of high water drainage and high peripheral speed, and it is possible to improve the sealing property and life. (2) Since the end face type seal is used for sea water and the sealing performance can be maintained by flushing water, there is a concern that the lubricating oil enclosed in the lip type seal part located inside the ship rather than the end face type seal leaks to the ocean. Is almost gone. (3) By arranging two end face seals in the front-rear direction and adjusting the flushing water supplied to each end face seal on the ship, the two end face seals can be used properly, so that a shaft sealing device can be used practically. And reliability are greatly improved.

[Brief description of drawings]

FIG. 1 is a side sectional view of a stern tube shaft sealing device as an embodiment of the present invention.

FIG. 2 is an enlarged view of a portion II of FIG. 1 and is a side sectional view showing a normal state.

FIG. 3 is a side cross-sectional view in the case of coping with the abnormal state.

FIG. 4 is a side sectional view showing a conventional stern tube shaft sealing device.

[Explanation of symbols]

 1 Propeller shaft 2 Stern tube bearing 3 Hull 4 Seal casing 5 Seal liner 6 and 7 End face type seal 8 and 9 Lip type seal 10 and 11 (Flushing water supply) passage 13 and 14 Flow rate adjusting device 61 and 71 Inner sliding face 62 , 72 Outer sliding surface 63, 73 Pressure chamber F Flushing water (fresh water)

 ─────────────────────────────────────────────────── --- Continuation of the front page (72) Inventor Takashi Omura 1-1, Atsunoura-machi, Nagasaki City Nagasaki Shipyard Co., Ltd. (72) Noboru Toge No. 1-1 Atsunoura-machi, Nagasaki City (72) Inventor Masami Akatsu, 1500 Katayanagi, Sakado, Saitama Prefecture, inside Eagle Industry Co., Ltd. (72) In Kiyoshi Uchiyama, 1500, Katayanagi, Sakado City, Saitama Prefecture, inside Eagle Industry Co., Ltd.

Claims (1)

[Claims] 1. A stern tube shaft sealing device, wherein a propeller shaft, a stern tube bearing that rotatably supports the propeller shaft with respect to a hull, and a rear end portion of the hull attached to surround the propeller shaft. A lip having a cylindrical seal casing and a seal liner attached to the propeller shaft and disposed inside the seal casing, the inner wall surface of the seal casing having an inner diameter end slidably contacting the seal liner. A mold seal is attached, and two end face type seals having a substantially L-shaped cross-section are attached to the seal liner on the stern side of the lip type seal inside the seal casing. An inner side that is disposed in the front-rear direction and that slidably faces the vertical sliding surfaces of the seal casings on the vertical surfaces of the end face type seals. And the outer sliding surfaces and pressure chambers located between the respective sliding surfaces and opening toward the vertical sliding surface of the seal casing are respectively formed, and flushing water is separately provided in the respective pressure chambers. A stern tube shaft sealing device, characterized in that each of the passages is capable of supplying the water, and a flushing water flow rate adjusting device is attached to each of the passages.