JPH0313469B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application] The present invention provides a connection for connecting two adjacent pipe ends having smooth surfaces and axially aligned, and for connecting said pipe ends to each other. Relating to a seal ring that is supported in both pipe ends so as to form a gap therebetween, and that has a recess that extends axially on opposing inner sides and opens toward the gap, and that is held in the recess. .

[Conventional technology]

This kind of sealing ring is manufactured by German Patent Publication No.
Known from No. 3206570. Here, a flange, at least one clamping element and a receiving half are loosely inserted onto each of the two pipe ends, which can be tightened together by screwing. A clamping chamber is formed between the flange and the housing half, into which a clamping member is inserted. The radially inner clamping edge of this clamping element is supported on the pipe end, and the radially outer clamping edge is overlaid by the clamping surface of the clamping chamber. When the clamping member is pressed in the axial direction, the pressing force is formed to expand the outer diameter of the clamping member and reduce both diameters, so that the clamping member is axially moved from the clamping chamber. It is formed to protrude. Each of the two storage chamber halves is provided with a sealing tightening chamber that opens toward the pipe abutting portion that accommodates the seal ring. The two housing halves are fastened together by screws.

The pipe connection device of the German patent mentioned above is particularly suitable for high pressures; however, when high pressures are applied, extrusion of the elastomer profile ring occurs in the area of the annular outer edge, which rests on the outer circumferential surface of the two pipe ends. arise. In such a case, the sealing material will find its way into the gap between the housing half and the pipe surface, which exists to the extent permitted by the manufacturing process. moreover,
In this type of pipe connection device, difficulties may arise in properly aligning the pipe ends to be connected. Additionally, sealing rings may be inappropriate for some pipe surfaces.

[Problem that the invention seeks to solve]

The aim of the invention is to improve the sealing properties and the ease of installation of the sealing ring described at the outset.

[Means for solving problems]

In order to solve the above problems, the seal ring of the present invention includes an elastomer molded ring and an inner ring, a. Once having an open annular groove, the two radially extending walls of the elastomer molded ring forming the annular groove are shaped so as to form an angle of less than 90 degrees with respect to the cylindrical surface of the pipe end. The distance between the two walls is formed so as to increase toward the outside in the radial direction of the elastomer molded product ring, and the annular groove provided in the outermost layer of the elastomer molded product ring is formed in the elastomer molded product ring. b. A hard inner ring that is loosely inserted into the annular groove that opens toward the center of the elastomer molded ring, and has a shape corresponding to the annular groove; As the thickness in the axial direction goes outward in the radial direction, the opening width of the annular groove that opens inward becomes larger, and the outer shape of the elastomer molded ring is approximately semicircular. , the radius of the annular rounded portion formed on the outer edge of both sides in the axial direction of the outer shape is the sum of the positive and negative tolerances determined regarding the outer diameter of the pipe to be connected, and the inner diameter of the housing half. It is set to be larger than the sum of the gap between the maximum pipe outer diameter and the gap.

The inner ring inserted into the annular groove of the elastomer molded ring is made of a hard material, such as a metal material or a plastic material, as described above, and when pressure is applied and the elastomer molded ring deforms as a sealing member, The elastomer molded ring itself remains substantially unchanged, and the elastomer molded ring deforms and performs a sealing action in substantially the predetermined position.

The rounded portion prevents extrusion and crushing of the sealing material. However, in this case, the radius of the rounded part and the inner diameter of the housing half take the maximum tolerance value,
It is advantageous if the outer diameter of the pipe is larger than the gap that occurs between the inner wall of the housing half and the outer circumference of the pipe when assembled, if the pipe has a minimum tolerance value.

In the case of a low-pressure pipe connection, it is sufficient to tighten the two flanges together by means of the clamping screws and to press the two receiving halves together via the sealing element arranged between them. In this case, a clamping chamber can be provided in the housing half and both flanges can be formed as flat cover plates. However, in this case, the clamping chamber is open toward the side opposite to the butt end of the pipe, and the two housing halves are not particularly screwed together, so that when pressure pulsations occur, the movement of the pipe end is slight. and if at least a portion of the sealing member is movable, pulsations occur within the outer periphery of the sealing member at the joint between the housing halves;
Due to the gap determined by the tolerances of the two housing halves, there is the problem of slight crushing of the sealing material.

In order to eliminate this drawback, it is advantageous to form an annular groove opening outwards in the center of the outer circumferential surface of the elastomer molded ring.

Providing an annular rim on the inner surface of the seal ring, which is sandwiched between the ends of the two pipes, facilitates the assembly of the seal ring and therefore the joining of the two pipes.

Correct positioning of this pipe connection device is therefore also ensured by the inner ring, since the annular rim of the inner ring serves as a stop for the abutting ends of the two pipes.

Particularly when the pipe diameter is large, it is desirable to construct the inner ring from a number of arcuate sections. In this case, if the inner ring has a cross section that slightly widens radially outward in a wedge-like shape, and this inner ring is loosely fitted into the annular groove of the seal ring, which has a shape that is approximately complementary to the cross section, , which makes installation easier. The inner ring, which is divided into several arcuate sections, is inexpensive to produce.
In order to prevent the individual arcuate portions from falling out of the elastomer molding ring when fitting them, the annular groove of the elastomer molding ring that accommodates the inner ring has a slightly undercut cross section; Therefore, the arcuate portions can be pushed into the grooves and fixed only by the elasticity of the elastomer molding.

Furthermore, the annular rim provided on the inner ring is
Since it can be easily moved between the two connected pipe ends, leakage of fluid within the pipe can be reduced.

The inner ring, which is composed of separate arcuate sections, has pipe ends that are e.g.
It is also advantageous when joining pipes with specially shaped pipe ends that are slightly curved around the circumference.
This also applies to pipes which have a lining extending outwardly from the end of the pipe to a certain extent over its entire circumference. In this case, the inner ring, which has an inner diameter approximately equal to the outer diameter of the pipe to which it is connected, cannot be moved at all, or even if it is possible, it is extremely difficult.

If there is a risk of damage to the pipe ends, it is a good idea to use an inner ring made of polytetrafluoroethylene. When an enameled pipe is used, an enameled layer may be provided on the end face of the pipe, in which case the annular rim of the inner ring acts as a buffer between the ends of the pipe. Such a buffering function is important. This is because when this pipe connection device is tightened,
This is because as the clamping member used in this pipe connection device bends, an axial force is created that presses the pipe ends together.

In a preferred embodiment of the invention, annular plates arranged on each side of the annular rim of the inner ring project below the elastomer molded ring, the thickness of this annular plate being typically approximately 0.5 mm.
selected. These two thin plates therefore cover the inner circumferential surface of the elastomeric molded ring, so that the elastomeric molded ring is protected from the influence of the medium flowing through the pipe.

In all embodiments, the inner ring is always arranged loosely in the annular groove of the elastomer molded ring, so that the sealing action of the sealing ring by the pressure of the medium is increased.

In many cases, it is necessary to connect various pipes based on different standards with various pipes based on old standards that have already been abolished, and pipes with different standards have different outer diameters. Often different. When connecting pipe ends with different outer diameters in this way, the seal ring,
Even if the partial annular part supported by one pipe end has a different inner diameter than the part supported by the other pipe end, it is possible to easily and reliably use the pipe connection device of the invention as described at the beginning. Connections that can withstand use can be made. In this case, to achieve a connection with as little media turbulence as possible,
It is preferable to form a conical inner flow path so that the inner diameter difference between the pipe ends where the inner rings are connected to each other gradually disappears (that is, so as to gently connect the inner surfaces of the pipe ends).

By using a seal ring with the above configuration, that is, a seal ring in which not only the shape of the inner flow path of the elastomer molded ring but also the inner flow path of the inner ring is standardized in stages, it is possible to and pipe ends based on the DIN series can be easily connected. It is therefore no longer necessary to use conventional reducing joints by welding or screwing.

Installation of the sealing ring according to the invention is facilitated by separating the inner ring and its annular rim. In this case, the annular rim is put into practical use by being fitted into an annular groove provided on the inner peripheral surface of the inner ring. When the annular rim is not fitted as described above, it is easy to fit the seal ring onto the pipe, slide it on the pipe, and move it to the abutment point of the two pipes to be connected, After moving, the annular rim can be elastically deformed and pushed into the annular groove provided on the inner peripheral surface of the inner ring.

When connecting pipes with large nominal diameters,
Preferably, the elastomer molded ring, the inner ring and/or the annular rim of the inner ring are each formed from an endless elongate material. Such a sealing ring is also suitable for flange connections used in the construction of containers and devices when the housing half and the flange are constructed as one piece.

For sealing particularly high pressures, the two inner annular edges of the elastomer molded ring, which rests on the outer surface of the two pipe ends to be connected, should form an angle β of less than 90° in cross section. Bye.
Irrespective of the cross-sectional shape of the inner annular groove of the elastomeric molded ring provided for receiving the inner ring, the configuration of the inner annular edge of the elastomeric molded ring has important implications with respect to its seal. That is, if the angle β defined above is designed to be at most 90°, preferably somewhat smaller, then the sealing will automatically take place in this part, especially at the height.

〔Example〕

Hereinafter, the present invention will be described based on embodiments with reference to the drawings.

In order to produce the pipe connection device according to FIG. 1, a flange 3, a clamping member 4 and a housing half 5 are first fitted into each of the two pipe ends 1, 2 which are to be joined against each other, Furthermore, the pipe ends 1 and 2 are inserted into the sealing ring 30, which consists of the elastomer molded ring 6 and the inner ring 10, so as to face each other with the gap 8 in between. Each housing half 5 is formed with an annular clamping chamber 7 that is open toward the flange 3, ie, on the right side, into which the clamping member 4 is inserted. This clamping member 4 consists of a truncated conical plate whose radially inner clamping edge 4a rests on the pipe ends 1 and 2, and whose radially outer clamping edge 4b rests on the pipe ends 1 and 2. Annex room 7
Although the clamping member 4 is elastically pushed into the inner side of the annular clamping surface 7a, when no pushing force is applied, the clamping member 4 is in a position pushed out from the corresponding housing half 5. When such a tightening member 4 is pushed into the corresponding tightening chamber 7, the tightening member 4 expands the inner periphery of the tightening chamber with its outer tightening edge 4b based on its truncated conical shape, and expands the inner periphery of the tightening chamber. The clamping edge 4a of the pipe is contracted so as to clamp the pipe ends 1 and 2. Further, each of the housing halves 5 is formed with a seal chamber 9 that opens toward the gap, that is, the pipe abutting portion 8, and this seal chamber 9 is formed in a conical shape so as to become narrower toward the adjacent flange 3. There is. The structure of the conical seal chamber 9 has an important meaning in improving the sealing function of the seal ring 30.

The pipe butt portion 8 is surrounded by a seal ring 30, which is loosely fitted into the annular groove 6a formed inside the elastomer molded ring 6 and is made of a hard material. It consists of an inner ring 10. The outer contour of the elastomer molded ring 6 has an approximately semicircular cross section and is adapted to correspond to the contour of the two sealing chambers 9 provided in the housing half 5, but with slightly larger dimensions. , when both housing halves 5 are moved closer to each other, inward pressure is applied to the seal ring 30 in the axial and radial directions.

The above-mentioned tightening is performed using four bolts 11 which are provided at equal angles on the outer circumference of the flange 3, pass through the through holes and the housing half 5, and have nuts attached to their tips.

FIG. 2 shows a sealing ring 30, an elastomer molding ring 6 and an inner ring 10, which connect the pipe 2 with a flange 3' provided on a fixed machine. The flange 3' is formed as part of the housing of the machine and is fixed to the housing, and the right part of the sealing chamber 9, which accommodates approximately the right half of the sealing ring 30, is provided at the end of the flange 3'. There is.

The tubular protrusion 1 formed inside the seal chamber 9 provided in the flange 3' corresponds to the pipe end on the right side in FIG. 1, and is similar to the pipe end 2 drawn on the left side. Connected. The flange 3 on the pipe 2 side is formed as a sleeve joint,
The female thread 20 of this sleeve joint is screwed into the male thread 21 of the machine side flange 3'. 5' in FIG. 2 corresponds to the left half of the two housing halves 5 in FIG. 1, and inside the housing half 5' there is a sealing chamber provided in the flange 3' Together with 9, the left half of the sealing chamber 9 that accommodates the sealing ring 30 is formed. Figure 2 shows the elastomer molded ring 6.
1 is compressed into a triangular sealing chamber 9 to form a triangular shape from the semicircular cross-sectional view shown in FIG. The inner ring, which is made of hard material, remains virtually undeformed in this case.

As is clear from FIGS. 1 and 3, a rounded portion R ₁ having the radius shown is formed behind the outer edge 6b of the elastomer molded ring 6 supported on the outer peripheral surface of the pipe ends 1 and 2. . Further, in the center of the outer peripheral surface of the seal ring, that is, the elastomer molded body ring 6, an annular groove r that opens outward is formed.

As shown in FIGS. 1, 2, and 4 to 9, an annular rim 10a is provided inside the inner ring 10, and this annular rim 10a serves as a stopper between the pipe ends 1 and 2. To position. B- in Figure 5
According to FIG. 4 showing cross section B, this inner ring 1
0 has a wedge-shaped cross section that becomes slightly wider toward the outside in the radial direction, and is loosely fitted into the annular groove 6a of the elastomer molded ring 6 that conforms to this cross section. The slope of this wedge is represented by the angle α.

According to FIG. 5, which is a sectional view taken along line A-A in FIG.
The inner ring 10 has three arcuate portions 10', 10'',
and 10, each extending over a circumferential angle of 120°.

The inner ring 10 shown in FIG. 7 is provided with an annular rim 10 projecting downward in the figure.
An annular plate 10b that covers the inner circumferential surface of the elastomer molded ring 6 is attached to the inner and outer sides of the annular rim at the protruding root portion. Annular plate 1
The thickness d of 0b is approximately 0.5 mm. In the embodiment shown in FIG. 6, the annular plate 10b has a slightly wider width with curved edges _R2 having radii at both ends;
This curved edge holds the elastomer molded ring 6 from both sides. In this way, the rounded portion having the radius of the elastomer molded body ring 6
Since R ₁ is supported by the curved edge of the annular plate 10b, an inexpensive, easy to install, low shore hardness elastomer molded ring can be used to house the seal ring 30.

In the embodiment shown schematically in FIG. 9, the pipe ends 1, 2 that are connected to each other have different outer diameters d ₁ , d ₂ . In this example, the portions of the rings 6 and 10 surrounding the thicker pipe end 1 of the elastomer molded ring 6 and the inner ring 10 are larger than the portions of the rings 6 and 10 surrounding the thinner pipe end 2. The inner surface of the annular rim 10a of the inner ring 10 is deformed to have a larger inner diameter, and the inner surface of the annular rim 10a of the inner ring 10 forms a larger diameter pipe 1 based on the difference in inner diameter of the pipe ends 1 and 2 to be connected.
It deforms into a truncated conical inner surface 10c having a large diameter on the side of the pipe 2 and a small diameter on the side of the small diameter pipe 2.

As is particularly clear from FIG. 3, the annular inner edge 6c of the elastomer molded ring 6 rests on the outer circumferential surfaces of the ends 1, 2 (not shown) of both pipes.
forms an angle β less than 90° in its cross section. This improves the sealing properties, especially at high pressures.

[Brief explanation of the drawing]

FIG. 1 is an axial sectional view of the pipe connecting device during assembly, FIG. 2 is an axial sectional view of the main parts of the pipe connecting device of another embodiment in the assembled state, and FIG. 3 is a seal ring according to the present invention. An axial sectional view of one embodiment of
Fig. 4 is a BB cross-sectional view of another embodiment of the seal ring shown in Fig. 5, Fig. 5 is an A-A cross-sectional view of Fig. 4, and Figs. 6, 7, and 8 are different from each other. FIG. 9 shows an axial sectional view of an embodiment of the inner ring, and FIG. 9 shows an axial sectional view of yet another embodiment of the seal ring in an installed state. 1, 2... Pipe end, 3, 3'... Flange,
4...Tightening member, 4a, 4b...Tightening edge, 5...
Housing half body, 6... Elastomer molded body ring, 6
a... Annular groove, 6b... Outer edge, 6c... Inner edge, 7... Tightening chamber, 7a... Tightening surface, 8... Gap, pipe butt portion, 9... Seal chamber, 10
...Inner ring, 10a...Annular rim, 10b...
...Annular plate, 10c...Inner surface, 10', 10'', 10
...Circular arc part, 11...Bolt, 20...Female thread, R ₁ , R ₂ ... Rounded part, rounded part, d ₁ , d ₂ ...
Outer diameter, r...annular groove, α, β...angle, 21...male thread.

Claims (1)

[Claims] 1. Used in a connecting device for connecting two adjacent pipe ends 1, 2 which have a smooth surface and are aligned in the axial direction; a housing half 5 which is supported by both pipe ends 1, 2 so as to form a gap 8 and has a recess or sealing chamber 9 extending axially on the opposite inner side and opening on the side of the gap;
A seal ring 30 held in the seal chamber 9
The seal ring 30 includes an elastomer molded ring 6 and an inner ring 10, and a) the elastomer molded ring 6 is formed along the inner peripheral surface and opens toward the center of the elastomer molded ring. having an annular groove 6a;
The two radially extending walls of the elastomer molded ring forming the annular groove form an angle of less than 90 degrees with respect to the cylindrical surface of the pipe ends 1, 2, so that The interval is formed so as to increase toward the outside in the radial direction of the elastomer molded product ring 6, and the annular groove provided in the outermost layer of the elastomer molded product ring 6
The hard inner ring 10, which is loosely inserted into the annular groove 6a which is formed to open on the side opposite to the center of the elastomer molded ring and which opens toward the center of the elastomer molded ring, has a shape corresponding to the annular groove. However, as the thickness in the axial direction goes outward in the radial direction, the opening width of the annular groove 6a that opens inward becomes larger, and the outer shape of the elastomer molded ring 6 is approximately semicircular. The radius of the annular rounded part R ₁ formed in the shape and formed on the outer edges of the outer shape on both sides in the axial direction is the sum of the positive and negative tolerances determined regarding the outer diameters of the pipes 1 and 2 to be connected, A seal ring that is larger than the sum of the gap between the inner diameter of the housing half 5 and the maximum allowable pipe outer diameter. 2. The inner ring 10 has an annular rim 10a on its inner peripheral surface that is located between the two pipe ends 1 and 2 and acts as a stopper.
Seal ring as described in section. 3. The inner ring 10 has a plurality of arcuate portions 10',
10'', 10.4 The seal ring according to any one of claims 1 and 2, wherein the inner ring 10 is made of metal. The seal ring according to any one of Item 3.5 The inner ring 10 is provided on both sides of the annular rim 10a and the elastomer molded body ring 6
The seal ring according to any one of claims 1 to 4, having an annular plate 10b projecting below. 6. The seal ring according to claim 5, wherein the annular plate 10b has a thickness of about 0.5 mm. 7. The seal ring according to any one of claims 5 and 6, wherein the inner ring 10 is made of polytetrafluoroethylene. 8. The seal ring according to any one of claims 5 to 7, wherein the annular plate 10b has a rounded portion _R2 for receiving both ends of the inner circumference of the elastomer molded ring 6. 9 When the outer diameters d ₁ and d ₂ of the two pipe ends are different, the inner circumferential surfaces of the elastomer molded body ring 6 at both ends surrounding the two pipe ends 1 and 2 have the outer diameter d _{1 .} , d ₂ , the seal ring according to any one of claims 1 to 8, having different inner diameters corresponding to d 2 . 10. When the inner diameters of the two pipe ends 1 and 2 are different, the inner ring 10 has an inner surface 10c having a contour that gently connects the inner circumferences of the pipe ends 1 and 2. The seal ring according to any one of Item 9. 11 The inner ring 10 and the annular rim 10
The seal ring according to any one of claims 2 to 10, wherein a is constructed as a separate body. 12 The annular rim 10a is the inner ring 10
12. The seal ring according to claim 11, wherein the seal ring is inserted into an annular groove formed in the inner circumferential surface of the seal ring. 13. The seal ring according to any one of claims 1 to 12, wherein the elastomer molded ring 6 is a member formed from an endless and elongated material. 14. The seal ring according to claim 1, wherein the inner ring 10 is a member formed from an endless elongated material. 15. The seal ring according to claim 14, wherein the annular projection 10a is a member formed from an endless and elongated material. 16. Claim 1, wherein the two annular inner edges 6c of the elastomer molded ring 6 surrounding the outer peripheries of the two pipe ends 1 and 2 form an angle β of 90° or less in their axial cross section. The seal ring according to any one of items 15 to 15.