JP3134088B2 - Seal of rotating body and sealing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seal for a rotating body and a casing for accommodating the rotating body, comprising a rotating ring or a sealing ring contained in the casing, wherein the inner or outer periphery of the sealing ring is rotated. The seal ring is engaged with the body or the casing, and the space surrounding the seal ring is made larger than the seal ring so that the seal ring is movable in the surrounding space in the axial direction, and the seal ring has an inner peripheral surface or an outer peripheral surface of the seal ring. The present invention relates to a seal for a rotating body which is movably held on the rotating body or a casing by frictional force generated by the rotating member.

[0002]

2. Description of the Prior Art Known seals of the above type, which are arranged on the outer rotor of a single rotating machine, as shown for example in FIG. 6 of U.S. Pat. It has the disadvantage that the pressure of the gaseous medium compresses against the mating sealing surfaces, which results in a loss of friction and a high level of wear on the non-smooth or minimally smooth sealing surfaces. This drawback is particularly problematic for a very fast rotating body having an outer peripheral speed of 20 m / sec or more. Therefore, the sealing action of the rotating body, which rotates very fast, is normally performed in a non-contact manner by a seal gap or labyrinth packing. Narrow seal gaps that result in good seals, however, require high manufacturing costs and are a consequence of thermal expansion and manufacturing tolerances that must be considered, especially when the perimeter to be sealed is of large diameter.
The size of the seal gap cannot be made small enough to provide a suitable gap seal. Known labyrinth packings have consequently several sealing ribs arranged axially in parallel, said sealing ribs projecting into the space surrounding the sealing ribs. Separated carbon rings are known for the sealing action of gas turbines on oil-lubricated bearings that rotate together and are slightly axially movable because the axial movement of the rotating parts is taken into account. To prevent premature wear of the carbon ring due to compression against the mating sealing surface due to the pressure of the medium to be sealed, French Patent 2,602,847 discloses that the pressure of the medium to be sealed against the sealing ring It has been proposed to substantially compensate for this and to apply fluid pressure on either side of the seal ring so that the seal ring is compressed to a central position and held in the central position. This fluid pressure is obtained by surface milling of a suitable, for example, rapidly rotating, rotating surface, said rotating surface accommodating the sealing ring with a space between the rotating surfaces. However, despite the high manufacturing costs, the sealing action of said seals is imperfect and the loss of pressurized gas and smoothness cannot be prevented.

[0003]

SUMMARY OF THE INVENTION The object of the invention is to find a seal for a rotating body which, in particular, enables a narrow seal gap without significant wear and is produced at low manufacturing costs. Also, it is advantageous for large diameters, where the required space is limited, it works well and increases the efficiency of the machine.

[0004]

According to the invention, this object is achieved in that the frictional force is greater than the axial force resulting from the pressure of the medium to be sealed acting on the side surfaces of the seal ring. The medium to be sealed is a labyrinth packing in such a way that an annular gap space is always formed between the two side surfaces of the sealing ring and the side surfaces of the surrounding space facing these side surfaces. Flow around the seal ring so that between the side surfaces of the surrounding space the seal ring is automatically positioned in the center non-contact position by brief mechanical contact with these side surfaces. To be solved.

A solution to the problem according to the invention is that the axial force resulting from the friction at the outer or inner circumference of the seal ring is less than the pressure at which the medium to be sealed acts axially on the seal ring. Is always big,
However, it defines a radial spring tension acting on the seal ring so that when it abuts the casing surface, the seal ring overcomes the adhesive force and can move in the axial direction, thereby defining the seal between the seal ring and the casing. In the gap, non-contact like a labyrinth packing is provided.

[0006] As a result of the present invention, the seal ring is positioned adjacent to the ideal surface of the center and the adjacent surface of the receiving space by a short abutment of direct mechanical contact, which cannot be obtained by measurement and precision assembly. Automatically moves to the ideal center position between adjacent surfaces due to relative rotation between. Relatively large friction force of adhesion circumferential surface of the seal ring is overcome, whereas insurmountable by the pressure of the medium to be sealed acting. Therefore, the space surrounding the seal ring can be made narrower than before, and any abutment due to manufacturing tolerances and / or thermal expansion due to the deformation of the seal ring alone does not create any danger of the seal ring becoming stuck. Alternatively, it easily occurs without permanent wear. Thus, the seal can be described as relating to a self-adjusting packing or a dynamic labyrinth packing, and as a result the sealing ring forms a labyrinth element.

In a manner similar to conventional labyrinth packings, several seal rings are axially continuous with one another,
It is also clear that each sealing ring is provided with an enclosing space. It is also evident that the components relating to the casing additionally rotate at different rotational speeds, since the seal according to the invention is generally suitable for the sealing action of rotating bodies that rotate relative to one another.

[0008] In the conventional piston ring method, the seal ring may or may not have an overlap joint.
Alternatively, it can be made from cast iron, steel or similar other metallic or non-metallic materials without joints. In order to obtain sufficient spring tension, a larger radial cross section and pressure compensation means are preferably provided on the two ring sides as seal rings with joints. Also, the sealing ring is held slightly larger, i.e. slightly compressed, compared to the surrounding space or casing. When fitted in this way, for example by a separate casing in the surrounding space, the sealing ring
Further, the rotating body can be surrounded so as to be movable with the initial tension.

[0009] Further sealing embodiments are described in the claims describing the embodiments.

[0010]

The present invention relates to non-limiting embodiments,
This is described in further detail below. In the accompanying drawings, only a diagrammatic view of the cross section of the seal ring is shown, without the lateral border of the ring.

The single rotating machine of the internal axis shown in FIG.
No. 3432915 (U.S. Pat. No. 4,714,417 or U.S. Pat.
No. 55), which is considered a part of the present invention. By mounting the inner rotor 1 and the outer rotor 2 of a single rotating machine around a fixed geometric axis,
Single rotating machine is suitable for high speed rotation, for example, 20 to 50 m / se
The outer peripheral speed of c is generated in the outer rotor 2 having a large value. The invention provides a non-contact seal, for example, on the side members 3, 4 of the outer rotor. The seals 5, 6 provided for this purpose have a seal ring or packing ring 8 surrounded by a space 7 formed as a groove in the side members 3, 4, and an outer peripheral surface 9 of the seal ring 8.
Are firmly engaged with the inner surface 10 of the circular cylinder of the machine casing 11 by a friction grip.

A radial annular surface 1 on the side of the space 7 surrounding a seal ring or other ring surface which is likewise arranged and forms a corresponding surrounding space 7 of the seal ring 8;
3, 14 have a distance from each other just enough to allow non-contact relative rotational movement when the seal ring 8 is in the ideal center position and positioning of the tumbling movement between the annular surfaces 13, 14; A corresponding minimum gap space for the gap seal is obtained. This position of the sealing ring 8 cannot be obtained by its precise assembly, but instead is automatically achieved by the abutment of the two sides on the surrounding groove surfaces 13, 14 at the start of the relative rotational movement. At this time, the friction grip or press-fit between the surfaces 9, 10 at the outer periphery of the seal ring is easily overcome by the corresponding mechanical force.

In order to limit the pressure differential of the gas acting on the seal ring 8, the ring surfaces 17, 18 defining the seal gaps 15, 16 are preferably restricted to a narrow area and the remainder of the sides of the seal ring. , Between the sides of the two seal rings, there are free spaces 20, 21 for pressure compensation.

In the embodiment according to FIGS. 2 to 5, the free spaces 20, 21 are formed by cuts in the sides of the seal ring forming steps 19 on each side. In the embodiment according to FIG. 6, the free space 21 is only on one side of the seal ring 8 and on the low-pressure side.

Instead of being formed by cuts forming steps 19, according to FIG. 7, free spaces 20 ', 21'
Is the inclined surface 2 on one or both sides of the seal ring 8
It can be formed by 2, 23 or conical surfaces.

According to the embodiment of FIG. 8, in the surface 24 which is held by the friction force, a groove 25 extending over the entire circumference with a radial cross-section is provided, said groove 25, friction The contact surface for rubbing is reduced and the surface pressure is increased. Also, the more difficult that the lubricant film to improve the friction force is formed, and a lubricating oil film, for example, via the bearings and gear lubrication of the machine of FIG. 1, so that leads to the sealing ring 8. Suitably, the discharge opening 26 leads outwardly from the groove space towards the low pressure side of the seal ring 8 so that there is no lubricating oil or gas pressure in the groove space.

FIG. 9 shows an embodiment of a seal in which a seal ring 8 is used, said seal ring 8 not having a side surface forming a free space, which is free space 20 ″. , 21 ″ are side surfaces 31 of the surrounding space,
32.

In the embodiment according to FIGS. 10 and 11, the sealing ring 8 has a larger cross-sectional area 31 defined laterally by abutting surfaces 29, 30 and covers the surface 13, 13 of the surrounding groove space 7, Seal gap 15 on 14,
The narrow ring surfaces 17, 18 that define 16 butt contact and damage to it are prevented. To ensure that the butt surfaces 29, 30 do not contribute to the sealing action resulting in uncontrollable movement of the surrounding groove space with respect to the surfaces 13, 14 due to the medium pressure, the two sides of the sealing ring 8 are provided with a channel 32 , 33 and / or the flow path 34.

Referring to FIG. 12, the butting surfaces 29, 30
In addition, a wedge-shaped sliding shoe-shaped projection 35 can be provided, and in the abutment on the surfaces 13 and 14 of the surrounding space 7, the projection 35 assists the formation of a slip film,
And as a result, the automatic centering of the sealing ring 8 in the surrounding space 7 is facilitated without any significant wear or even pitting.

In the embodiment according to FIGS. 13 to 15, the side surfaces 36, 37 of the seal ring are provided by a rotating tool 38 with a radial groove 39 of limited depth, said groove 39 being For example, it is formed by a pot-shaped wheel 38 shown by a circle in FIG. 14 or a milling machine. Due to these grooves 39, for example, FIG.
Pressure compensation is possible in exactly the same way as in the free spaces 20, 21. The seal is obtained again in the manner of labyrinth packing by a narrow gap between the sealing ring 8 and the surrounding groove space 7. The side surface of the seal ring 8 is prevented from being flattened between the narrow grooves empty, groove chamber 7
The danger that the seal ring 8 will not move at the abutment at the side surfaces 13, 14 is eliminated.

In the embodiment shown in FIGS. 16-18, a slightly curved deformed portion of the seal ring 8, such as exaggerated deflecting portions 40, 41, 42, causes An operation similar to that of the embodiment is obtained. Such a wavy seal ring 8
Also provides an improved sealing action in the circumferential direction of the ring 8.

[0022] As indicated by the embodiment, the seal ring 8, to one another by friction Shi pairs body to be sealed acting friction, 2 and 3, and the outer peripheral surface 9 or according to Figure 18 from Figure 6, or The seal ring 8 is preferably a stationary body, ie the embodiment of FIG. 1, although any of its inner peripheral surfaces 12 can be engaged according to FIGS. 4 and 5 and the seal ring 8 can be provided adhesively to the rotating body. Is adhered to the main body which is the machine casing 11 in the above. However, when the seal ring 8 is provided by being adhered to the rotating body, the centrifugal force must be considered in order to ensure that the seal ring 8 can move to the center position during high-speed rotation. To form the space 7, whether the seal ring 8 surrounds or is surrounded by the rotating body, whether the seal ring 8 is adhered to the rotating body or is surrounded by the rotating body without touching the rotating body. Is not important for the functioning of the present invention.

The accompanying drawings show only a few possible embodiments of the seal of the invention, and the shaping of the sealing ring 8 and the associated surrounding space 7 can be varied in various ways. It is clear.

[Brief description of the drawings]

FIG. 1 is an axial cross-sectional view through a central mandrel of a known type of single rotating machine.

FIG. 2 shows a seal ring held in a casing, FIG.
1 is an enlarged sectional view of the seal of the present invention of a single rotating machine according to the present invention.

3 shows a side view of the peripheral area of the seal according to FIG. 2;

FIG. 4 is an enlarged cross-sectional view of a seal having a seal ring held by a rotating body.

5 shows a side view of the peripheral area of the seal according to FIG. 4;

FIG. 6 is a sectional view showing a further embodiment of the seal of the present invention.

FIG. 7 shows a further embodiment of the seal of the invention.
FIG.

FIG. 8 shows a further embodiment of the seal of the invention.
FIG.

FIG. 9 shows a further embodiment of the seal of the invention.
FIG.

FIG. 10 is a sectional view showing a further embodiment of the seal of the present invention.

FIG. 11 shows a side view of the peripheral area of the seal according to FIG. 10;

FIG. 12 shows the butt surface of the seal according to FIG. 10;

FIG. 13 is a sectional view showing a further embodiment of the seal of the present invention.

14 shows a side view of the peripheral area of the seal according to FIG. 13;

FIG. 15 shows a narrowly defined portion of the seal ring, illustrating an embodiment of traversing the lateral surface of the seal ring.

FIG. 16 is a sectional view showing a further embodiment of the seal of the present invention.

17 shows a side view of the peripheral area of the seal according to FIG. 16;

FIG. 18 shows a section through the peripheral area of the seal according to FIG. 16;

[Explanation of symbols]

 2 ... rotating body 7 ... surrounding space 8 ... seal ring 9 ... outer peripheral surface 11 ... casing 13, 14 ... side surface 15, 16 ... annular gap space 17, 18 ... seal gap surface 19; 19 '' ... step 20, 21; 20 '', 21 '' ... free space 24 ... contact surface 25 ... groove of the whole circumference 26 ... outflow opening 29, 30 ... butting surface 31 ... cross-sectional area 32 ... recess 34 ... flow path 35 ... protrusion 36, 37 ... Side surface 39 ... groove 40, 41, 42 ... deflection part

──────────────────────────────────────────────────続 き Continued on the front page (56) References US Patent 4,714,417 (US, A) French Patent 2,602,847 (FR, B) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16J 15/16- 15/30 F01C 19/08

Claims (11)

(57) [Claims] 1. A seal for a rotating body and a casing for housing the rotating body, the seal including a seal ring (8) housed in the rotating body ( 3 ) or the casing (11), and an inner periphery of the seal ring. Alternatively, the outer periphery is engaged with the rotating body or the casing, and the space (7) surrounding the seal ring (8) is made larger than the seal ring (8) so that the seal ring (8) surrounds the seal ring (8) in the axial direction. The rotating body is configured to be movable, and the seal ring is movably held by the rotating body ( 3 ) or the casing (11) by frictional force on the inner peripheral surface or the outer peripheral surface of the seal ring (8). in sealing, the frictional force is greater than the axial force resulting from <br/> pressure of the medium to be sealed acting on the side table surface of the sheet Ruringu (8)
Unishi, whereby the two side surfaces of the sealing ring, this
Around the way the seal ring of the medium to be seal as the annular gap space is always formed labyrinth seal (8) between the side surfaces of the surrounding space (7) facing these side surfaces to flow, preparative sealing ring between the side surfaces (13, 14) of Rikakomi space (7) (8)
There by brief mechanical abutment contact with these side surfaces (13, 14), automatically brought located in the non-contact position of the center
Sealing of the rotating body that is to so that is. 2. Seal ring (8) or seal ring
Box (8)SurroundingAt least the side surface of space (7)
Also in one,Engaged by frictionOneC
Of Luling (8)Peripheral surfaceFrom (9)Separated by a predetermined distance
For pressure compensationSelfFree space (20, 21; 2
0 ", 21"),The free space is cut
Formed by theNotch,whileVoid space (15, 1
6) on the annular seal gap surfaces (17, 18) definingStep
(19; 19 '')Concatenated,Between the annular seals
Gap surface (17, 18)Is equal to the predetermined distance,
The seal for a rotating body according to claim 1. 3. The side of the seal ring surrounds the seal ring (8) and is centrally positioned in the surrounding space (7) .
Because of and for protecting the seal gap surface (17, 18)
An annular surrounding butt surface (29, 30);
Said butting surfaces (29, 30) laterally defining a cross-sectional area (31) of a wider sealing ring (8);
The seal for a rotating body according to claim 1. 4. A seal ring (8) provided for pressure compensation, wherein two axially facing ring sides of the seal ring (8) pass through the seal ring (8), or the seal ring (8). 2. The rotary body seal according to claim 1, wherein the seals are interconnected by recesses (32) extending radially across the sides of (8). 5. A wedge-shaped projection (35) is formed on the butt surface (29) for the formation of a sliding oil film.
A seal for a rotating body according to claim 3. 6. Side surfaces (36, 3) of the sealing ring (8).
2. The rotary body seal according to claim 1, wherein 7) faces radially via a groove (39). 7. A sealing ring (8) having a continuous deflection portion (4) on its outer circumference to form individual butt surfaces.
0, 41, 42), the seal of the rotating body according to claim 1. 8. The seal ring (8) engages at least one annular inner or outer peripheral surface of the rotating body or the casing, and the annular inner or outer peripheral surface is narrower than the seal ring (8). 2. The seal of the rotating body according to 1. 9. The contact surface (24) of the sealing ring (8).
However, in order to hold the seal ring (8) by static friction,
9. The rotary body seal according to claim 8, wherein the seal is reduced by a full circumferential groove (25). 10. The space of the groove (25) is formed by an outlet opening (2).
6) connected to the outside of the seal ring (8) by
A seal for a rotating body according to claim 9. 11. A method for sealing a rotating body housed in a casing, wherein the sealing is performed by a seal ring (8) surrounding the rotating body ( 3 ), wherein the inner circumference or the outer circumference of the seal ring (8) is radial. The casing and elasticity
In the sealing method of one engaging of the preliminary rotation body, axial force resulting from the friction force Te periphery or inner periphery odor seal ring, medium to be sealed is to the sealing ring (8) From the pressure acting in the axial direction
Always greater, however radius <br/> abutment Then the sealing ring casing surface (13, 14) acts on the sealing ring on a movable der so that the axial direction by overcoming the adhesive force (8)
A sealing method in which a directional spring tension is defined such that the seal is non-contacting like a labyrinth packing in the sealing gap (15, 16) between the sealing ring (8) and the casing (7, 11).