JPH0330556B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a stand tube seal, and particularly aims to improve its seawater sealing properties and its effectiveness in preventing marine pollution.

Conventionally, it has been known that a type of stantube seal seals seawater directly using an oil seal with oil on the back. There is a risk that the surface will be damaged, and this damage may cause seawater to enter the cabin or oil for lubricating the bearings to leak out of the vessel and pollute the ocean.

In view of the above points, the present invention allows the seawater to gradually pass between the end face of the inner stepped part of the case member and the outer peripheral face of the shaft sleeve, using the seawater intrusion pressure as back pressure on the seawater side of the in-plane oil seal. A limited leakage seal for seawater that forms a possible sealing surface is provided, and a leakage recovery line that opens into the interior space of the limited leakage seal is provided in the case member, and from this leakage recovery line, pressure fluid is released. The pressure supply line extending to the supply source is branched and connected via a switching valve.

Embodiments of the stand tube seal of the present invention will be described below with reference to the drawings. FIG. 1 shows the first embodiment. The stand tube seal, indicated as a whole by 1, is installed in the shaft hole opening of the ship body 3 so as to seal between the sleeve 2 which is externally fixed to a shaft (not shown) and the ship body 3 into which the shaft is inserted. 4 indicates a part of the propeller attached to the tip of the shaft.

In this stand tube seal 1, reference numeral 5 denotes a first case fixed to the end surface of the vessel body 3 via a gasket 10. ) towards the second, third, fourth and fifth cases 6,
7, 8, and 9 are fixed in series. between the first case 5 and the second case 6, between the second case 6 and the third case 7, and between the third case 7 and the fourth case
The spaces between the cases 8 are sealed by O-rings 11, 12, and 13, and a slurry removing gasket (not shown) such as felt is interposed between the fourth case 8 and the fifth case 9. There is. The second, third, and fourth cases 6, 7, and 8 have substantially the same appearance, and each has an annular step formed on its inner peripheral surface, and a limited leakage seal is provided in each step. Barrel segment seals 14, 15, 16 are provided. Each segment seal 14, 15, 16 is prevented from rotating relative to the cases 5, 6, 7 by a not shown knock pin, and the garter spring 1
7, 18, 19 and compression spring 2
0, 21, and 22 to form a sliding seal surface between the sleeve 2 and the end surfaces of the cases 5, 6, and 7. A packing 23 that slides on the circumferential surface of the sleeve 2 is clamped between the fourth case 8 and the fifth case 9. Reference numeral 24 denotes a mechanical seal disposed on the inboard side of each of the segment seals 14, 15, and 16, and includes a fixed-side sliding ring 25 fitted to the inner step of the first case 5; The cover ring 26 fixed to the sleeve 2 is prevented from rotating by a knock pin (not shown), and the rotating side sliding ring 27 follows the rotation of the shaft.
A sliding sealing surface is formed on the abutting surface. The sliding ring 27 on the rotating side is elastically biased toward the sliding ring 25 on the stationary side by a coil spring 28. 29
and 30 indicate an O-ring. Further, 31 opens into a gap space 32 partitioned by the mechanical seal 24 and a segment seal 14 (hereinafter referred to as a first segment seal) arranged on the inner periphery of the second case 6; From the ship body 3 to the 1st
The first pipeline is arranged for case 5 of
The leakage recovery line is connected to leakage recovery equipment (not shown) such as pumps and tanks arranged inside the ship, and collects leakage that has entered the space 32 into the ship. Similarly, the first segment seal 1
4 and a segment seal 15 (hereinafter referred to as the second segment seal) disposed on the inner periphery of the third case 7.
The leakage recovery line 33 is opened, and is partitioned by the second segment seal 15 and a segment seal 16 (hereinafter referred to as the third segment seal) arranged on the inner periphery of the fourth case 8. A third leakage recovery line 35 opens in the gap space 36 to collect leakage.

The stand tube seal 1 with the above configuration is shown in A in the figure.
This system prevents both the leakage of seawater into the cabin as shown in B and the leakage of oil inside the ship to the outside of the ship as shown in B, and operates as follows. That is, in the above configuration, the packing 23 located closest to the seawater A side
The third segment seal 16 hardly functions as a seal against seawater, and the third segment seal 16 is mainly affected by the biasing force of the garter spring 19 and the compression spring 22, and by passing from the inner circumference of the case 9 through the packing 23 and sealing the case 8. Using the pressure of the seawater A entering the inner step as a back pressure, a sealing surface is formed between the end face of the inner step of the case 8 and the outer circumferential surface of the sleeve 2, and functions as a seawater seal. As mentioned above, since the segment seal 16 is a limited leakage type seal, the seawater A gradually passes through the segment seal 16 into the gap space 36 inside the machine, and the seal 16 is well lubricated, resulting in a low load. is maintained.
For the seawater that has entered the gap space 36, the third
Most of the leaked liquid is recovered into the ship from the leakage recovery line 35. As a result, the pressure of the seawater remaining in the gap space 36 is significantly reduced, and the second segment seal 15 can seal the seawater in a state where it is easier to seal. Applicable stun tube seal 1
In this way, the seal part for seawater is multi-stage (3 stages).
The system is designed to gradually reduce the amount of seawater leaking into the aircraft, and ultimately to completely prevent it from entering the cabin. On the other hand, regarding leakage of onboard oil B to the outside of the ship,
The mechanical seal 24 is in charge of this sealing, and even if oil leaks from the mechanical seal 24, it is collected into the ship from the first leak recovery line 31 to prevent the oil from leaking out of the ship. completely prevent it. Therefore, with the stand tube seal 1 having the above configuration, it is possible to completely seal both seawater and in-machine oil.

In addition, in the above configuration, it is also extremely effective to provide a mechanism for feeding pressurized fluid from inside the ship toward the gap space 36 using the third leakage recovery line 35 located closest to the seawater side. . In other words, in the event that a problem such as breakage occurs in the seal part of the above structure for some reason, pressurized fluid is sent from the line 35 and the pressure of the fluid prevents seawater or slurry from entering the machine. As shown in FIG. 2, a pressure supply line 53 extending to a pressure fluid supply source 52 is branched and connected to a leakage recovery line 35 extending from a space 36 to a leakage recovery section 51, and a switching valve is installed at the connection point. 54 and 55 are provided. That is, normally the third segment seal 1
The seawater A that has gradually passed into the space 36 inside the machine 6 is collected from the leakage recovery line 35 to the leakage recovery section 51, and in the event of an emergency such as seal breakage, the switching valve 54 is closed and the switching valve 55 is opened. Particularly, the pressure fluid from the pressure fluid supply source 52 is pumped into the space 36 via the pressure supply line 53 and the leakage recovery line 35, and the pressure fluid flows from the sealing surface of the third segment seal 16 into the seawater. By flowing out into A, the intrusion of the seawater A is prevented. This pressure fluid also flows through the second segment seal 1
5 to the space 34 inside the aircraft,
Even if the leaked in-machine oil B should reach this gap space 34 due to seal breakage or the like, the in-machine oil B will not leak into the seawater A. As the pressure fluid, it is preferable to use seawater, air, nitrogen gas, clean water, etc., which will not cause problems such as pollution even if leaked into the seawater. When used, it works to remove marine products from the seal.

Next, FIG. 3 shows a stand tube seal 37 according to a second embodiment of the present invention. In this stand tube seal 37, the case has four members 38, 39, 40, 4
1, and the first and third cases 3
8, 40 each in the step part of the emotion formed on the inner peripheral surface.
The segment seals 42 and 43 are arranged so as to face each other and sandwich the second case 39 therebetween. In addition, in this embodiment, the leakage recovery line 44,
Two lines are provided as shown by the reference numeral 45, and the pressure of line 45 on the seawater side is set lower than the pressure of the other line 44 so that more leakage can be recovered from the line 45. . Accordingly, the segment seal 42 on the inside of the machine mainly functions to seal the differential pressure between the two. Since most of the configurations are the same as those of the first embodiment, the same reference numerals are given and the explanation will be omitted.

Next, FIG. 4 shows a stand tube seal 46 according to a third embodiment of the present invention. This stand tube seal 46 is constructed so that the end-face type rubber seal 47 carries out the functions of the first and second segment seals 14 and 15 in the first embodiment. That is, the end face type rubber seal 47 is placed on the inside of the segment seal 48.
is arranged in a fixed state on the outer periphery of the sleeve 2,
Most of the seawater that has passed through the segment seal 48, which forms a sliding seal surface between it and the end surface of the first case 38, is recovered into the ship from the leakage recovery line 45 on the seawater side. Rubber seal 47
becomes a seal with very low load and exhibits excellent sealing function. Further, instead of this end face type rubber seal 47, a lip seal 50 may be used as shown in a stand tube seal 49 in FIG. Also, segment seals 14, 1 used as limited leakage seals in common to all the above embodiments.
5, 16, 42, 43, and 48 may be replaced with floating ring seals, and it is also possible to use a lip seal instead of the mechanical seal 24 as a seal for internal oil.

As explained above, the stub tube seal of the present invention lubricates the limited leakage type seal of the seawater seal to prevent seawater gradually passing into the inside of the aircraft and in-flight oil gradually leaking from the in-flight oil seal. In addition to recovering liquid from the leakage recovery line, in the event of an emergency such as seal damage, the leakage recovery line is connected to the pressure fluid supply source side using a switching valve to supply pressure fluid to the inside of the machine of the limited leak type seal. Therefore, it is possible to prevent the intrusion of seawater or the leakage of oil inside the aircraft, so that it not only exhibits excellent sealing performance against both seawater and oil inside the aircraft, but also prevents marine pollution.

[Brief explanation of drawings]

Figures 1, 3, 4, and 5 are
FIG. 2 is a half-cut sectional view of a stub tube seal according to a different embodiment of the present invention, and FIG. 2 is an explanatory diagram of piping of a stub tube seal according to a first embodiment. 1, 37, 46, 49... Stun tube seal, 2... Sleeve, 3... Ship body, 4... Propeller, 5, 6, 7, 8, 9, 38, 39, 4
0,41...Case, 14,15,16,42,
43, 48... Segment seal, 23... Packing, 24... Mechanical seal, 31, 33,
35, 44, 45...Leakage recovery line, 32, 3
4, 36...Gap space, 47...End face type rubber seal, 50...Lip seal.

Claims (1)

[Claims] 1. An annular case member is placed around the outer periphery of the shaft sleeve, and a seal for in-flight oil is placed on the inner periphery of the case member at a position closer to the inside of the aircraft, and on the seawater side of the seal, seawater pressure is used as back pressure. A seawater limited leakage seal is disposed between the inner stepped end face of the case member and the outer peripheral surface of the shaft sleeve to form a sealing surface through which seawater can gradually pass, and the case member is provided with a seawater limited leakage seal. A leakage recovery line that opens into the space inside the machine of the mold seal is provided, and a pressure supply line extending from the leakage recovery line to a pressure fluid supply source is branched and connected via a switching valve. Stunche Yub Seal.