DD159559A5 - Gate valves - Google Patents

Abstract

The invention relates to a gate valve, e.g. is used in pipelines, the aim of the invention is a small size and low effort in the operation of the slide, with an absolute closure must be gerantiert. For this purpose, the sealing lines between housing and closure is to be designed accordingly. According to the invention the object is achieved in that the sealing lines over the entire length of two halves, which together reach an X-shape. The invention can be used for piping systems for flowing media. Fig. 1

Description

27/10/81

"" "AP F16K / 23O 700/3

59 328 26

Gate valve Field of application of the invention

The present invention relates to a gate valve with a housing having as a cylindrical Strömungsieitung an interior which is to extend horizontally and describes a seat, and a closure which is provided with a sealing cord made of elastomer and is moved by vertical displacement, this direction cord attaches to the seat of the housing and has the same basic shape as this.

Characteristic of the known technical solutions

The conventional gate valves of this type have a sealing line whose basic shape is a wedge. Their axial dimension must on the one hand be compatible with the plugs prescribed for the pipelines and on the other hand ensure a low wear of the elastomeric seal during the repeated opening and closing operations.

Now these two conditions are antagonistic. In order to reduce the wear of the seal, the friction of this seal on its seat, which is necessary to obtain the desired compression of the elastomer, must be reduced, and consequently at every point the path of the closure between the moment in which the seal Seat touched, and the moment in which the pressure in question is reached, be reduced. For this purpose, one must increase the angle that forms the seat with the direction of movement of the closure, but unfortunately grows by this increase in the axial dimension of the gate valve,

- 2 - 27.10.81

59 328 26

A solution to this problem has become known through the PR-PS 2 139 61 6 and 2 178 457, wherein last represents an additional patent.

According to the solutions contained in these references, the seat and closure on both sides of a plane of symmetry passing through the axis of the actuating spindle and perpendicular to the axis of a flow nozzle have two continuous, closed, mutually corresponding surfaces which progressively curve.

In each variant of this patented gate valve, each ruled surface which is seated on either side of said plane of symmetry includes an upper curved portion approximately transverse to the flow axis, a lower curved portion coincident with the cylindrical inner flow surface, and between the two both above and below a diametrical area represented by the flow axis, a transitional section that is approximately spiraling, in the form of a twisted oblique plane connecting said upper and lower sections, as close as possible to the cylindrical flow surface surrounds.

This control surface, which is thus formed by two rectilinear generatrices, has a middle seal line, which is a closed curve. At each point of this seal line, the tangent plane of the seat-forming surface - the plane formed by the rectilinear generatrix and the tangent of the seal line at this point - forms an angle with the direction of movement of the shutter or the axis of the actuating spindle at a predetermined angle to that Example is 20 °, at least equal.

- 3 ~ 27.10.81

59 328 2б

Along a sealing area extending over more than half of the seal line, the angle between the tangent plane at each point of the seal line and the axis of the actuator spindle is approximately constant.

The lower generatrices of the flow nozzle may be rectilinear or have a deviation that forms an indentation or bulge against which the lower part of the closure abuts.

Thanks to this arrangement, the sealing contact between the seat and the closure by a rubber seal on the entire closed periphery of the seat is completely continuous, so that the gate valve is completely sealed in the closed position, even and especially in said transition portion of the sealing surface.

In addition, thanks to the already mentioned smallest angle of 20 °, the sliding of the seal on the seat when closing the shutter is significantly reduced in relation to the previous gate valves. This results in less wear of the seal of the closure. However, the force required to operate this gate valve is relatively high.

Object of the invention

The object of the invention is to provide a further solution which is compatible with the previous one and more advantageous from the point of view of the force required to open the shutter.

- 4 - 27.10.81

59 328 26

Explanation of the essence of the invention

The invention has for its object to provide a gate valve with a housing having a cylindrical, horizontally disposed interior which defines a seat, and with a closure which is provided with a sealing cord and vertically displaceable, wherein the sealing cord adapted to the seat of the housing is to create, in which by the geometric shape of the seal line between the seat and closure an absolute seal with small sizes is achieved and the force required to operate the gate valve remains minimal.

According to the invention, the object is achieved in that the sealing line of the seat perpendicular to the axis of the flow line has an X-shaped basic shape and along its entire length by displacement of two sealing line halves to each other, which together have the basic shape of a wedge, along the said axis is formed.

The two halves of the seal line intersect approximately in the horizontal diametrical plane of the interior. Each half is a set surface having an upwardly bent portion, approximately transversal to the axis XX, of the flow axis, with a downwardly curved lower portion in the a cylindrical inner surface of the inner space passes, and between two, above and below a diametrical region, represented by the flow axis, an upper and a lower transition portion are arranged spirally, the upper and

- 5 - 27.10.81

59 328 26

reconnect the lower section by bypassing the cylindrical interior for the shortest distance.

In an advantageous embodiment, which ensures minimum axial dimensions, each sealing line half is designed as described in PR-PS 2 139 616 or in PR-PS 2 178 457.

In this pail, to simplify manufacture, the portion of each half of the seal line that is above the area of the plunger axis - axis XX- may be replaced by two portions of a surface that converge toward that axis and through curved lower transition portions to the Surfaces are extended, which are below the said range.

When, in the lower portion of the seat, the angle formed by the tangential plane of the sealing surface with the axis of the actuating spindle changes favorably, the headline of the sealing cord is determined to contact the same at all points except its lower portion where In this first contact a bearing clearance is present, which gradually grows on each side to the lowest point of the interior.

Thus, during the closing phase of the closure, when the sealing contact between the closure and the seat has been made on the majority of the sealing cord except for said lower portion, the distances between the sealing cord and the seat resting on the sealing cord

- 6 - 27.10.81

59 328 26

Lower loops of each seal line, as they move away from the diametrical plane of the nozzle, larger, gradually smaller, and the sealing contact is gradually produced, wherein the seal is also gradually compressed. This non-uniformity of the sealing contacts over the entire circumference of the sealing line and this gradual coming into contact with the seat and increase in the radial or normal compression of the sealing cord or seal at least partially in the sense of a uniform compression of the sealing cord at the end of the closing path of the closure, the change of Angle o £, which forms the tangential plane of the sealing surface along its center line in the lower portion of the seat with the axis of the actuating spindle.

A complete or almost uniform squeezing of the sealing cord can be achieved if this bearing clearance is developed according to the formula j = a sincC- b, where a and b are constants. This can be easily achieved with a flow conduit having a circular cross-section by giving the lower part of the sealing cord or the head line, as seen along the flow axis, a round shape whose radius is greater than that of the inner space.

With regard to the parts to be manufactured, it may be desirable to replace the intersections of X with flats on the seat and on the weatherstrip by straight sections that are almost vertical when seen from the side and on a short sealing line.

- 7 - 27.10.81

59 328 26

If the nozzle at right angles to the closure an inner or outer protruding portion, for. B. protrusions and cross-connections, has, the lower part of the seat is correspondingly changed by areas that are progressively connected to its remaining area.

The sealing cord follows the outer circumference of a closure plate, which is composed of a cylindrical lower part, which is parallel to the axis X-X, a cuboid intermediate part and a wedge-shaped upper part with a horizontal tip, which is perpendicular to the axis X-X. The shutter consists of two shutter halves which are joined according to a vertical plane perpendicular to the X-X axis, each wedge-shaped shutter half being a thin shell provided with internal reinforcing projections and with locating and locating recesses.

Each closure half has an inner rabbit which bears against a horizontal outer surface of the other closure half. The sealing cord consists of a seal that envelops the entire closure. Have the closure halves protrusions, they are equipped at their inner and outer tops with the seal,

embodiment

The invention will be explained in more detail below by exemplary embodiments. In the accompanying drawings show:

- 8 ~ 27.10.81

59 328 26

Pig. 1 is a view in longitudinal section of a gate valve according to the invention with closure in the closed position, wherein the upper part of the gate valve is not shown;

Pig. 2: a cross-sectional view taken along line 2-2 of Pig. 1;

Pig. 3: a view in longitudinal section analogous to Pig. 1 of the gate valve without its closure;

Pig. 4: a cross-sectional view taken along line 4-4 of Pig. 3;

Pig. 5: the longitudinal section of a further embodiment of the gate valve according to the invention analogous to Pig. 1;

Pig · б: the cross section according to line 6-6 according to Pig. 5; Pig. 7: a view analogous to Pig. 5 without closure;

Fig. 8 is a cross-sectional view taken along line 8-8 of Pig. 7;

Pig. 9: An intersection looks like line 9-9 of Pig. 5 »which is partially open;

Fig. 10 is a sectional view of the closure taken along line 10 - 10 of Fig. 6;

- 9 - 27.10.31

59 328 26

Pig. 11: a perspective schematic view of the closure of the embodiment of the Pig. 4 to 10;

Pig. Fig. 12 is a perspective view of the seal line according to this second embodiment;

Fig. 13: a partial section diametrically to the Sirömungsachse with two closure halves;

14 shows a further partial section diametrically to the flow axis with two closure halves;

Pig. 15: another partial section diametrically to the flow axis with two closure halves;

Pig, 16: another other partial section diametrically to the flow axis with two closure halves;

Fig. 17 is a fragmentary sectional view taken in a horizontal plane slightly below the flow axis, showing the shape of the upper part of the shutter halves;

Fig. 18 is a cross-sectional view of a projection showing the diameter of the tangential planes of the sealing surface with the direction of the actuating spindle in the lower part of the junction with the cylindrical flow surface represented by a circle;

- 10 - 27.10.81

59 328 26

Fig. 19 is a projection drawing as a front view and a plan view showing the sealing line of a gate valve according to PR-PS 2 13 9 61b;

FIG. 20: the projection drawing analogous to FIG. 19, on which comparatively the sealing lines of an embodiment of the present invention are shown;

Fig. 21: the projection drawing analogous to Fig. 20 of the second embodiment;

Fig. 22 is a view in longitudinal section of a variant of the gate valve according to the invention, in which the flow nozzle has a low-lying bearing with vertical walls at the lower side of the path of the closure;

Fig. 23 is a section along lines 23-23 of Fig. 22; Fig. 24 is a section along lines 24-24 of Fig. 23;

Fig. 25 is a view in longitudinal section of another variant similar to that of Fig. 22, but where the recess is connected to the flow nozzle not by vertical walls, but by sloping walls;

Fig. 26: a half-section along the lines 26-26 of Fig. 25;

- 11 - 27.10.81

59 328 26

Pig. FIG. 27: a half section along lines 27-27 of FIG. 26; FIG.

Pig. FIG. 28 is a view in longitudinal section of another variant analogous to that of FIG. 22, but where the lower generatrices of the flow nozzle have a deviation in the form of a projection in the interior of this nozzle; FIG.

FIG. 29 shows a half section along the lines 29-29 of FIG. 28; FIG.

Fig. 30: a half section along the lines 30 - 30 of Fig. 29l

Fig. 31 is a view analogous to Figs. 5 to 8 for a variant of the second embodiment of the invention;

FIG. 32 shows the cross section along line 32 - 32 according to FIG. 31; FIG. FIG. 33 is a view analogous to FIG. 31 without a closure; FIG.

Fig. 34 is a cross-sectional view taken along lines 34-34 of Fig. 33;

FIG. 35: a partial view in longitudinal section of a further embodiment of the gate valve according to the invention; FIG.

Fig. 36: the view of this gate valve in cross section along the line 36 - 36 of Fig. 35;

- 12 - 27.10.81

59 328 26

Pig. Figure 37 is a longitudinal section of the cord upon first contact of this cord with the seat;

Fig. 38 is a sectional view taken along line 38-38 of Fig. 37;

FIG. 39 is a view similar to FIG. 38 when the closure is completely closed; FIG.

Fig. 40 shows the cross-section of the cord upon contact of this cord with the seat at the lowest point of the flow conduit;

41: a view analogous to FIG. 40 during the complete closure of the closure.

The gate valve shown in Figs. 1 to 4 comprises a housing 1 in T-shape of cast iron or other metal alloy or plastic. The housing

1 has a nozzle 2 with the axis X-X for the inlet and outlet of the transported medium, said nozzle

2 is intended, for example, by pipe flanges to be connected to a line, not shown, and a tube housing 3 with the axis Y-Y perpendicular to the axis X-X, which forms the web of the T-element. For the sake of description, the axis X-X should be horizontal and the axis Y-Y vertical, with the tube housing 3 extending from the nozzle 2 upwards. Only the lower part of the tube housing 3 is shown; its upper part has, as is known, a lid which closes off the slide housing and serves as a sealed guide for the actuating spindle of the closure.

- 13 - 27.10.81

59 328 26

The nozzle 2 has a cylindrical interior 4 with a circular cross section, while the housing 3 has an interior space 5 with the axis YY, which is also cylindrical, but has an almost elliptical cross section. The interior 4 is interrupted in the extension of the tubular housing 3 by a seat 6 of special shape, which will be described later.

To the seat 6, a shutter 7 is to be applied by displacement between an open upper position and a closed lower position, which is moved by means of a threaded actuating spindle 8 along the axis Y-Y. The upper end of this threaded spindle 8 is mounted so that it rotates in the upper lid of the housing 1, but does not move, and its lower end cooperates with an actuating nut, not shown, which is contained in an upper housing 9 of the closure. Like the housing 1, the shutter 7 has as planes of symmetry a vertical plane Q with the axes X-X and Y-Y and a vertical plane P with the axis Y-Y which is perpendicular to the axis X-X.

The closure 7, which will be described later, may be made of any suitable material, such as e.g. Gray cast iron, ductile iron, steel, a copper alloy or plastic, and produced by any suitable method (die casting, swaging, machining, etc.). In this example, the closure is hollow and consists of two closure halves 7a and 7b which, as will be seen later, are joined together and completely covered with rubber.

- 14 - 27.10.81

59 328 26

The shutter 7 has the basic shape of a perpendicular to the axis XX plate, which is adapted to the dimensions of the cylindrical space 4 of the nozzle 2 and the shapes of the seat 6 so that it can be inserted between both halves of the nozzle 2 to close on the Seat б hang up. It contains in its upper part except the housing 9, which includes the nut of the actuating spindle 8, two pairs of ribs or lateral guide ribs 10 which are parallel to the axis Y-Y and are located on each side of the vertical plane Q «

The guide ribs 10 cooperate with two vertical guide ribs 11, which are located in the vertical plane P of the gate valve, in the interior of the housing 3, projecting into the interior space 5.

Two embodiments of the seat б and the shutter 7 will be described below.

The first embodiment of the seat б and the closure 7 is shown in FIGS. 1 to 4 and 20.

The shape of the seat б is derived directly from the shape described in FR-PS 2 139 616, as can be seen in the comparison of the projection drawings of FIGS. 19 and 20.

According to this FR-PS, as shown in Fig. 19 geometrically, the transverse profile of the seat б or more precisely the projection of the curved and continuous sealing line on the vertical plane Q through the lines A, B, D, C and

- 15 - 27.10.81

59 328 26

A1, B1, D1, C1 are shown. This profile consists of two symmetric curves in relation to the plane P and has the basic shape of a ship's hull. It can be seen that the upper curve sections A, E and A1, E1, which are transverse to the flow axis XX, that is almost vertical run, the lower curve sections D, C and D1, C1, which coincide with the course of the plane P and completely on the cylindrical flow space A, and the transition portions E, B, D and E1, B1, D1 which are spiraling, intersect the axis X - X in B and B1 and connect the upper transverse portions to the lower portions, each seal line half , The lines A, B, D, C and A1, B1, D1, C1 are the projections of the center line of the seat 6, which consists of two ruled surfaces whose generatrices perpendicular to the axis X - X in the upper sections A, E and A1, E1 and parallel to the axis X - X in the coincident lower portions D, C and D1, G1 and which develop in the intermediate sections E, B, D and E1, B1 and D1 between squareness and parallelism, like the steps of a spiral staircase ,

It should be recalled that the sealing lines A, E, B, D and A1, E1, B1, D1 at each point enable a tangential plane of the seat 6 which forms, with the axis YY, an angle <6 which is a predetermined value , z. B. 20 °, is almost equal (tangent planes with the course K1, T and K2, T on Fig. 18). From D to C and from D1 to C1, the angle oC gradually increases from the minimum of 20 ° to 90 °.

- 16 - 27.10.81

59 328 26

The upper part of the projection drawing of Fig. 20 is the projection of the sealing line of a slide according to the invention on the same plane Q. The curves A, E, B, D, C and A2, E2, B2, D2, 02 are respectively identical to the curves A, E, B, D, C and A1, E1, B1, D1, 01 of Fig. 19 and have the same upper sections A, E, A2, E2, the lower sections D, C and D2, C2 and the transitions and connecting sections between the upper sections and the lower sections E, B, D and Ξ2, B2, D2 and correspond to the same geometrical Besti_umungen, The same applies to the conditions at the tangential planes of the seat along these two curves.

In order to reduce the largest longitudinal dimension of the seat 6 (distance A, A1 and A, A2 of FIGS. 19 and 20), however, by moving parallel to the axis XX, the two symmetrical curves have been approximated to be in B or B2 (Fig. 20) on the axis XX. It follows that the largest longitudinal dimension A, A2 in relation to the axis X-X is smaller than the above dimension A, A1, wherein the reduction of the dimension is equal to the size of the considered displacement.

Consequently, the seat б has a mean sealing line 61 which, when projected onto the plane Q, represents the entirety of the curves A, E, B, D, C and A2, E2, B2, D2, 02. The sealing line 61 is shown in FIGS. 3 and 4 by a dotted line on the seat б and concretized by the head 71 of an elastic sealing cord 12, which is located on the closure 7, said head 71 has exactly the same shape. The sealing line 61

- 17 - 27.10.81

59 328 26

is composed of the totality of two lines that intersect at the ends of the horizontal diameter of the nozzle 2 on the axis X-X. The sections of each half of the seat 6 are accordingly:

two upper sections 62 lying almost in a plane transverse to the flow axis X-X, for the sealing line 61 corresponding to A, E and A2, E2;

two upper transition sections 63, which are spiral, lie above the diametrical area of the flow axis and correspond to E, B and E2, B2;

- Two lower transition sections 64, which are horizontal, below the diametrical portion of the flow axis X-X, beyond the vertical plane P related to these B, D and B2, D2 correspond;

two cylindrical lower sections 65 which coincide with the inner space 4, run parallel to the flow axis X-X and correspond to D, C and D2, C2

All of these surface portions are continuous with each other, and these surface portions on the seat 6 correspond to sections 72; 73; 74; 75 of the sealing line 61 on the sealing cord 12 and the closure 7th

The seal line 61 of the seat 6 and head 71 of the shutter 7 thus have a basic shape, which corresponds to an X, seen from the side. Every half of the line up

- 18 - 27.10.81

59 328 26

one side of the plane P has a vertex B at each end of the horizontal diameter of the spigot 2. The result is the v / eiteren sealing surfaces that intersect in the diametrical region of the flow axis X-X; above this diametrical area, the areas widened at the upper part converge to the diametrical area of the X-X axis. Under this diametrical area, the sealing surfaces converge from the lower part to the diametrical portion of the X-X axis.

In other words, the surface portions lying above the diametrical portion of the axis XX and on one side of the plane P continue under this diametrical portion on the other side of said plane P. This extension ensures continuity despite the geometrical discontinuity. which is marked by the vertex B, for the sealing surface portions lying on the same side of the plane P.

As shown in perspective in Fig. 12 for a later described embodiment, the sealing line 61 at the head 71 is in fact a closed curve that encompasses the entire circumference of the sealing surfaces, that is the cylindrical inner traction 4, with two vertices B, B2 symmetrical to the plane Q with the axes XX and YY (plane of Fig. 1, 3 and 20). The sealing line 61 and the head 71 are superimposed at 'shut-off position of the gate valve,

- 19 - 27.10.81

59 328 26

At the shutter 7 (Figure 11), the sealing cord 12 of nearly circular cross-section extends around a shutter plate 76 whose median plane is the plane Q and which has a lower portion 77 of constant thickness and semi-cylindrical (that is, its dimension the axis XX) and whose horizontal diameter is above the plunging axis XX, then an intermediate part 78 which is cuboid and also thick, then an upper part in the form of a wedge, the edge of which intersects the axis X - X at right angles and after diverged up to the upper loops of the line at the head 71. The wedge has in the upper part a dimension equal to the axis X-X, which is above that of the intermediate part and the lower part of the closure plate 76. The lateral guide ribs 10 project at the upper part 79 on each side of the plane P.

The sealing cord 12 extends along the entire edge of the upper part 79 and at the lower part of the semi-cylindrical lower part 77, at each axial end thereof. From there, the two lower curved portions of the sealing surface meet at the vertices of the upper part 79 and converge to the diametrical portion of the axis X-X,

Referring to Figs. 2 and 4 of the closure and seat 6 shown in the plane P, the individual portions of the sealing surfaces extend symmetrically with respect to the plane Q in the plane P corresponding to arcs showing on each side of the plane P the following approximate values , which are therefore to be calculated twice, have:

- 20 - 27.10.81

59 328 26

a) 62-72: about 60 °;

b) 63-73: about 30 °;

c) 64-74: about 30 °;

d) 65-75: about 60 °.

We shall consider later the embodiment of the shutter 7 corresponding to the first and second embodiments.

A second embodiment is shown in FIGS. 5 to 12 and 19.

Besser To better understand the construction of the second embodiment relative to the first, we compare the projection drawings 20 and 21.

The principle of intersecting seal lines and surfaces has been retained, but for reasons of simplicity, sections 62-72 and 63-73 (or A, E, B and A, E, B) have been placed over the diametrical portion of axis XX that is, the top portions and the top intermediate portions of continuous curvature that develop in a spiral shape were defined by two straight-line convergent planes (A, P, B, and A ^, P ¹ , B ² ; ), where the half angle cC at the top is axis XX.

cC at the top greater than or equal to 20 ° in relation to

Under the diametrical portion of the axis X-X, the sealing surfaces and lines of the first embodiment were maintained.

- 21 - 27.10.81

59 328 2б

It can be seen that this simplification in the upper region of the sealing surfaces and lines is accompanied by a small enlargement of the largest longitudinal dimension at the same angle C , because the distance A, A of FIG. 21 is greater than the distance A, A of FIG. 20. But this largest longitudinal dimension remains at the same angle <C still lower than that of the former gate valve (distance A, A of Fig. 19).

More specifically, in this embodiment, the upper portion 62 of the seat 6 is composed of:

- Two semi-elliptic flat surfaces 62 a, which represent the intersections of the two convergent planes that are symmetrical to the plane P, with the wall of the nozzle 2. These semi-elliptical surfaces 62a extend from the junction between the tube body 3 and the nozzle 2 to a region nearly halfway between the horizontal diametral plane passing through the axis XX and the junction between the tube body 3 and the nozzle 2 (sections A, F and A ^, F ¹ of Fig. 21);

- Two spirally extending intermediate surfaces 63 a, the

extend to the said diametral plane and

1 ?

correspond to the sections F, B and F, B of FIG. 21. These intermediate surfaces 63a ensure the gradual transition to the two lower transition sections 64 ·

The two lower transition sections 64 are, as in the first embodiment, inclined surfaces which extend from an area on the axis X-X to approximately half the height between

- 22 - 27.10.81

59 328 26

see the axis X-X and the lower generatrix of the inner space 4 extend. There are inclined surfaces in the form of rotated slated planes, that is, helical ruled surfaces, which arise by Mantelliriien, based on a sectional curve of the seat 6 with the cylindrical interior 4. The lower transition sections 64 show rotational development about a vertical axis as one follows their cutting curve with the cylindrical flow space. The intermediate surfaces 63a and the lower transition portions 64 allow at all points of the center line or the sealing line 61 has a tangential plane which forms a minimum angle of 20 ° with the axis YY, which angle in the lower part, where the lower transition portions 64 to the with Connecting interior 4 coinciding lower sections 65, gradually increases up to 90 °.

The middle sealing line 61 of the seat 6 consists, as above, of two lines symmetrical with respect to the plane P of the gate valve. These two lines can be seen on the plan view of Fig. 9 and on the lower part of Fig. 21; they are closed and continuous, but have significant course or direction changes (vertices) in the course of the plane P. The sealing line 61 is also shown in perspective in FIG. 12. As above, the seal of the closure 7 rests on the seat 6 along this sealing line 61, which is the same for the seat 6 and the closure 7 (identical line of the head 71).

When projected onto the plane Q (Figures 5 and 7), the seal line 61 forms an X consisting of a tip-down V located on a bottom inverted U

- 23 - 27.10.81

59 328 26

while in the first embodiment the upper V is replaced by an upper U.

In the plane P (Figure 6), the sealing cord 12 and the sealing line of the head 71 appear only in the upper portion 62; 72 in the form of a ¹ semi-ellipse, on a part of the upper transition section 63; 73 and on the lower section 65; 75, while on the lower transition section 64; 74 are hidden.

We will now discuss the structure of the two shutter halves 7a; 7b of the shutter 7 for the two mentioned embodiments describe «

These two shutter halves 7a; 7b consist of two thin shells (FIG. 13) which have reinforcements 13 on each side of the closure on the axis XX to allow connection of connecting elements consisting of a pair of conical projections 14 formed on a closure half - e.g. , B. 7a - are projecting and in corresponding conical recesses 15 of the other closure half - z. B. 7b - are fitted. There are also inner projections 16 abutting each other provided (Fig. 17), which are present on the shutter halves 7a and 7b at the same time and constitute spacers which compress the thin walls of the shutter 7 when molding a skirt or seal 17 made of rubber prevent, which is injected under pressure into a mold in which the shutter 7 is located.

In addition, as seen in Fig. 10, the two shutter halves 7a; 7b inside two noses 18, which on one

- 24 - 27.10.81

59 328 2б

Shutter half begin 7 and to the upper horizontal inner wall of the other shutter half 7 b and on the other hand directly under the housing 9 with mother, v / obei they pass through the plane P, create. These noses should • each separation of the closure halves 7a; 7b by shearing during the closing process, when a foreign body from a single side of the plane P represents a disability prevent.

The variable thickness elastomeric seal 17 is reinforced to form the sealing cord 12 or the head marking the seal line 61 and thinned in the plane of symmetry P-P or joint plane of the shutter halves 7aj 7b. The two closure halves 7a; 7b are independent of each other on their entire surface, inside and outside, the inner projections 16 and the lugs 14 included, with the seal 17 coated. They are fastened with the aid of a binder, ie without screws. Only the tips of the lugs 14 and the bottom of the recesses 15 are not covered.

In terms of shape, none of the shutter halves 7a; 7b a draft, so they are malleable without a core.

It can be seen, comparing FIGS. 13 and 14 and 15, 16, that the sealing cord 12 of the gasket 17 is divided into two symmetrical parts on each closure half 7a; 7b (FIGS. 13-14) may be present or may be present only on one closure half, 7b, for example, the other closure half 7a being correspondingly truncated (FIGS. 15-16), so that the connection joint in this region is a right-angled one Obstacle forms, the possible penetration of medium

- 25 - 27.10.81

59 328 26

counteracts between the two closure shells.

It is also found, if one the section of Fig. 17 with the Pig. 13 to 16 compares that the sealing cord 12 in the upper sealing portion under the diametrical portion of the axis X-X runs differently than in the lower portion; in the latter case, the sealing cord 12 lies on a surface which lies in the vicinity of the cylindrical inner space 4 or coincides with it, while in the upper portions it lies on a surface which is almost transverse to the axis XX, as already described above the sealing cord 12 is directed everywhere against the seat 6.

The shutter 7 »from the adhesive bond of the shutter halves 7a; 7b has convex surfaces on its entire circumference, the shape of which corresponds to the concave surfaces forming the seat 6. "

In this embodiment, the closure 7 may be made in one piece, but the molding is more difficult than with two parts.

We shall now consider the horizontal projections of the sealing lines of the gate valve according to the invention (Figures 20 and 21) and the gate valve according to FR-PS 2 139 616.

Under the influence of the pressure of the transported medium in front of or behind the slide, the closure 7 is pressed in the closed position onto the part of the seat б which opposes this pressure, and the sealing line 61

- 26 - 27.10.81

59 328 26

When projected onto the plane Q of FIG. 5, it corresponds to the line A, B, C (FIGS. 20 and 21). If this seal line is projected onto the diametric plane passing through the axis X-X and perpendicular to the axis YY, the shaded crescent-shaped surface of the lower part of Fig. 21 is obtained for the second embodiment of the invention Force are applied to open the shutter 7 and to overcome the pressure of the medium to which it is exposed. The purpose of opening the closure 7 to be overcome resistance means basic effect. This resistance or this basic effect is the product of the pressure to be overcome and the projected area, which is hatched in FIG. It can thus be seen that the greater the projected area, the greater is the basic effect or resistance to be overcome for the same pressure to be overcome.

By comparison, it can be seen that the area projected in Fig. 20 for the closure 7 of the second embodiment of the invention is significantly smaller in relation to that of the closure of the aforementioned FR-PS 2 139 6i6 (seal line and hatched projected area of Fig. 19) is, of course, with the same diameter of the interior 4 ·

With an inner diameter 4 of 150 mm and a pressure of 16 bar to be overcome at the opening of the shutter 7, the projected area (Figure 19) was a shutter according to the earlier one

2 Patent of the applicant 250 cm, and the opening force or the basic effect was 4 000 kg.

- 27 - 27.10.81

59 328 2б

In a closure 7 according to the second embodiment of the

Invention reduces the projected area to 50 cm (Pig. 20) and reduces the force to be overcome at the opening to 800 kg.

It can be seen in Fig. 20 (projected area for the first embodiment), an area which is even smaller than that of the Fig, 21, that is quite smaller than that of FIG. 19 for the former gate valve,

Thanks to this significant reduction in the basic effect can be used with the gate valve of the invention, an actuator with lower performance and'geringerem space.

Moreover, the upper part of the schematic representation of FIGS. 19 to 21 shows the reduction in the longitudinal dimension, that is the distance between the flanges of the nozzle 2, which was measured parallel to the axis XX, with the same diameter of the interior 4 in relation to a Gate valve according to the previously mentioned FR-PS 2 139 61b and this with the same minimum angle between the axis XX and the tangential plane of the sealing surface along the sealing line.

Finally, in the closure 7 of the invention, thanks to the shape of the seat 6 and the concerted shape of the closure halves 7a and 7b, the advantage is obtained of approaching or withdrawing from the seat 6 with a minimum of friction, since the surfaces, which must cling to each other, so that an Abel I tune succeeds; they shift to each other without an oracle. from that

- 28 - 27.10.81

59 328 26

advantageously results in that the seal 17 made of elastomer, and especially its sealing cord 12, is exposed to a minimum of wear.

In the following, variants of the two embodiments mentioned are described. These variants relate only to the lower part of the seat 6 and correspond to the case in which the nozzle 2 has an inner or outer projection.

According to the variant of FIGS. 22 to 24, the housing 1 has on each side of the plane P, ie about the axis YY, a transverse recess 20, which represents an outer protuberance or a projection in the lowest point with respect to the lower generatrices of the nozzle 2 , Such a transverse recess 20 serves the lower part of the closure 7 at the end of its closing path as storage.

This transverse recess 20 has the shape of a cylindrical control surface whose generatrices are parallel to those of the cylindrical interior 4 and which are connected by walls which are parallel to the plane P, with this interior space 4. Consequently, the sealing surface of the seat 6 of the shutter 7 is changed simply by replacing the cylindrical lower portion 65 with a lower portion 66 which coincides with both a portion of the cylindrical interior 4 and the transverse recess 20. Consequently, the lower part 66 is a ruled surface which is partly cylindrical and partly has a shape which extends downwards beyond the cylindrical shape and whose rectilinear generatrices develop between those of the inner space 4 and those of the transverse recess 20, with which they finally coincide.

- 29 - 27.10.81

59 328 26

According to the variant of Pigl 25 to 27, the housing 1 as above has a transverse recess 21 with an outer protrusion with respect to the nozzle 2, but this transverse recess 21 is connected to the interior 4 by bevels 22. The lower portion 65 of the sealing surface is replaced by a lower part 67, which constitutes a control surface and whose rectilinear generatrices develop progressively between those of the cylindrical inner space 4 and those of the bevels 22.

According to the variant of Figs. 28 to 30, the housing 1 has an inner projection 23 on each side of the plane P. This projection 23 is a control surface representing a cylindrical excess thickness with an axis parallel to the axis XX and a larger radius as the interior 4 has; it is connected by circular bevels 24 with the cylindrical interior 4.

The lower part of the closure 7 must rest tightly on the inner projection 23, especially on the circular bevels 24. Polarity of the sealing surface of the seat 6 of the closure 7 is changed by the cylindrical lower portion 65 is replaced by a lower control part 68 whose Generals extending progressively from the generatrices of the interior space 4 "which are parallel to the axis XX, to which the bevels 24 develop.

In each of the three variants mentioned, the lower part of the closure 7, and above all its sealing line of the head 71, is naturally changed in the same way as the seating surface. The same variants for the first embodiment of the invention are possible.

- 30 - 27.10.81

59 328 26

For the variant of Pig. 25 to 27 and 28 to 30, it is important that the angle which the tangent of the slope is 22 or 24 along the sealing line 61 with the axis YY, corresponds to <£ of 20 ° to the minimum angle or more. On the entire length of the sealing line 61 is thus a constant V / inkel present, which is at least 20 °. This has the advantage that the elastic seal 17 operates on the entire circumference of the seat under the same conditions. Thus, for a given position of the closure 7, the compression of the seal 17, which is calculated perpendicular to the support surface, is constant over the entire circumference of the seat. If one changes the position of the shutter 7, this compression assumes a new fourth, which is then uniformly maintained over the entire circumference of the seat 6.

These two variants have a further advantage, which consists in that the closure 7 is guided and supported in its lower part at the closing end. It is an advantage that is all the more interesting, as the support and guide surface of the guide ribs 10 of the shutter 7 on the guide ribs 11 of the housing 1 has a limited height.

To the variant of Figs. 31 to 34, it should be noted that in both embodiments of Figs. 1 to 4 and Figs. To 8 is a critical crossing point B, B on the sealing line 61, which on the seat б and the seal of the closure 7 must match.

On the other hand, if the manufacturing tolerances of the seat б on the one hand and of the closure 7 on the other hand are too great, there is a risk of a slight displacement of this crossing.

- 31 - 27.10.81

59 328 26

point on the seat 6 and on the closure 7, so the risk of imperfect sealing ·

Therefore, if wide manufacturing tolerances are foreseeable, it is appropriate to replace this critical crossing point with a short sealing line 80 which, when vertically projected onto the plane Q, constitutes a binding element. This seal line 80 is objectified by a head line 81 "on the shutter 7 on either side of and in the vicinity of the diametral plane of the axis XX, this head line 81 being on a small rectilinear portion 82 of the sealing cord 12 of the shutter 7 (FIG. 31), as well by a connecting flattening 83 between the upper transition section 63 and lower transition section 64 on the seat 6 (Figure 33).

Thus, on one or the other side of the plane of symmetry P-P between the seat 6 and the shutter 7, a slight shift is possible, because between the head line 81 of the straight section 82 and the corresponding flattening 83 of the seat 6, there will always come into sealing contact.

The gate valve on FIGS. 35 and 36 has a housing 1 which corresponds to that of FIGS. 31 to 34. The closure corresponds overall to the closure 7 of FIGS. 31 and 32, the only difference being the shape of the head line 171 of its sealing cord 112.

- 32 - 27.10.81

59 328 26

In fact, the head line 171 in the upper and intermediate parts of the sealing cord 112, that is, when tracing the distance ABCDEPG on either side of the plane P, has the same shape as the sealing line 61 of the seat 6, but somewhat widened, that is, one at each point constant distance or a constant superposition i shifted perpendicular to the seat 6.

In the lower part of the sealing cord 112, between the two points G, which are the upper boundaries of the portion of the seat 6 which coincides with the inner space 4 of the neck 2, the shape of the head line 171 is in contrast to that of the sealing line 61 declining. More specifically, when viewed at the flow axis X-X (Fig. 2), the lower part of the seal line 171 is in the form of a circular arc having a radius slightly larger than the radius of the inner space 4 of the nozzle 2.

When the shutter 107 lowers to close the inner space 4, there is a moment t .., in which all points of the head line 171, which are above the two points G, that is, all points such. B. A, B, G, D, E, F and G, simultaneously with the seal line 61 of the seat б come into contact (Fig. 7 and 8). At the same time t. There is a bearing clearance j under the two points G. This play gradually increases from a zero value at the points G to a maximum value J _M at the low point H lying in the plane P on the YY axis.

- 33 - 27.10.81

59 328 2б

As the closure continues to descend in a vertical path s to its full closed position, in the upper and lower portions of the sealing cord 112, that is, above the two points G, this sealing cord 112 progressively presses on the seat 6 together, with or without almost sliding on it, until it reaches a squeeze or overlay value i (Figure 9). As in all of these sections A, B, C, D, E, P, G, the tangential plane of the seat 6 along the seal line 61 forms an almost constant angle with the displacement direction YY. For example, if this angle is 20 ° or 30 °, i = s · sin oC = constant = i in all points.

Under the two points G, in the previous embodiments, the contact 71 - 61 occurs simultaneously at the time t .., as well as above the points G. Since the angle cC in this section is between <£ and 90 °, the superposition i changes = s. sin <£ from one point to another, s at point H.

on the other hand, from s. sin oC at point G to s · sin 90 ° =

In contrast, according to Figs. 35 and 36, among the points G: i = s. sin tC - j, so that it suffices to have j = s at every point. sin об- i = s (sin oC- sin oC ) (I) so that the overlay i is still equal to i in this lower section. The formula (I) is therefore: j = a sin cC - b, with a = s and b = s. sin oC,

By way of example, for £ = 30 °, the superimpositions i at the points A and H at the time t2 of the complete close closure after a V / eg of 2 mm

- 34 - 27.10.81

59 328 26

Time ti and a bearing clearance at the point H of 1 mm at the time ti are calculated as follows according to the formula (I):

- from point A to point G: i _Q = 2 χ sin 30 ° = 1 mm at point H (j = 1 mm): i = 2 x sin 90 ° - 1 = 1 mm

at an intermediate point K, which is below G and is angularly offset by 30 ° with respect to H, one has cC- 60 °, and a bearing clearance j = 0.732 mm is necessary to obtain the same superposition: i = 2 χ sin 60 ° - 0.732 = 2 χ 0.866 - 0.732 = 1 mm.

One thus obtains a superposition or a pinch i, which is constant and equal to i over the entire circumference of the sealing cord 12. This peculiarity is useful and advantageous, as insufficient overlay in some points can lead to a lack of seal, while excessive overlay causes severe wear of the seal cord 12. The above formula (I), that is, j = s, sin &gt; i _Q = s (sin oC-sin oC _Q ) > gives the outline of the head line 171 », which leads to a uniform value i of i over its entire circumference. In practice, one can assume a circular arc shape under the two points G, whose radius R1 of the head line 171 is slightly larger than the radius R of the inner space 4, wherein

R1 = R + i.

It can be seen that the center line 171 a of the compressed cross-section 171 b of the sealing cord 112 in the fully closed position with the sealing line 61 of

27.10.81 - 35 - 59 328 2б

Seat б coincides, while it is in the previous embodiments, the line of the head 71, which, at time t .., with this sealing line 61 coincides.

The arrangement described with reference to FIGS. 35 and 36 can be applied to all the embodiments mentioned in which the angle tangential plane-axis Y-Y in the lower part of the seat 6 changes, that is to say for all the embodiments mentioned except those of FIGS 27 and 28 to 30. When the intersection of the halves of the seal lines 61 is punctiform (Figures 1 to 30), the intersection replaces the vertical section C, D, E of Figures 1 and 2, but the remainder of the seal cord 12 is so as defined above.

Of course, the term "head line" used here must be understood in a broad sense; this line may in certain cases be a narrow surface if the sealing cord 12 has a rectangular, trapezoidal or crescent-shaped cross section.

Throughout the present work it has been assumed that the axis X-X is horizontal and the axis Y-Y is vertical. Nevertheless, it will be understood that the gate valve of the invention may be used in any desired direction, for example, with a flow axis X-X extending vertically or obliquely.

Claims (14)

- 36 - 27.10.81 59 328 26 Claim for information A gate valve having a housing having a cylindrical, horizontally disposed interior defining a seat, and a closure provided with a sealing cord made of elastomeric and vertically displaceable, the sealing cord being adapted to the seat of the housing and the same general shape has like this, characterized in that a sealing line (61) of the seat (6) perpendicular to the axis (X - X) of the interior (4), over its entire or virtually the entire length, at zv / ei mutually displaceable sealing line halves, the Together form a general wedge shape, achieved a general X-Porm. 2. Gate valve according to item 1, characterized in that the two halves of the sealing line (61) approximately in the horizontal diametrical plane of the interior (4) intersect. Gate valve according to points 1 and 2, characterized in that each half of the sealing line (61) is a set surface having an upwardly bent portion (62) approximately transversal to the axis (X-X) corresponding to the flow axis, wherein a downwardly curved lower portion (65) merges with the inner cylindrical surface of the inner space (4), and between the two, above and below a diametrical portion, represented by the flow axis, an upper transition portion (63) and a lower one Transition section (64) are arranged spirally, - 37 - 27.10.81 59 328 26 connecting the upper portion (62) and lower portion (65) in reverse by bypassing the cylindrical inner space (4) by the shortest route. Gate valve according to item 3, characterized in that the part of each half of the sealing line (61) lying above the area of the axis (X - X) is defined by two parts of a surface (62a) facing this axis ( X - X), replaced and extended by curved lower transition sections (64), which are below this range, » 5. Gate valve according to one of the items 1 to 4, characterized in that critical points of intersection are provided with flats (83) on the seat (6) and on the sealing cord (12) which are approximately perpendicular to a short sealing line (80). 6, gate valve according to one of the items 1 to 5, characterized in that the sealing cord (12) follows the outer periphery of a closure plate (76) consisting of a cylindrical lower part (77) which is parallel to the axis (X - X) is located, a cuboid intermediate part (78) and a wedge-shaped upper part (79) with a horizontal tip, which is perpendicular to the axis (X - X) composed. 7. Gate valve according to one of the items 1 to 6, characterized in that the closure (7) consists of two closure halves (7a, 7b) corresponding to a vertical plane (P) perpendicular to the axis (X - X) - 38 - 27.10.81 59 328 26 each wedge-shaped closure half (7a; 7b) is a thin shell provided with internal projections (16) and with projections (14) and recesses (15). 8. Gate valve according to item 7i, characterized in that each closure half (7a, 7b) carries an internal nose (18) which bears against a horizontal outer surface of the other closure half (7b, 7a). 9. Gate valve according to one of the items 1 to 8, characterized in that the sealing cord (12) consists of a seal (17) which surrounds the entire closure (7). 10. Gate valve according to item 9 », characterized in that each closure half (7a, 7b) is provided at its inner and outer upper parts with the seal (17). 11. Gate valve according to one of the items 1 to 10, characterized in that a connecting piece (2) at right angles to the closure (7) has projections (23) and transverse recesses (20; 21), wherein the lower part of the seat (6) in corresponding Way with pads that overlap on its remaining part, is provided. 12. Gate valve according to item 3 or 4 », characterized in that, when the angle of the contact plane in the lower part is changed, a head line (171) of a sealing cord (112) is determined so as to simultaneously engage the seat (6) in all its points, except - 39 - 27.10.81 59 328 26 in its lower part, or, during the first contact, a bearing clearance (j) progressively increasing from each side to the lower point of the inner space (4), 13. Gate valve according to item 12, characterized in that the bearing clearance (j) is given by a radius of the head line (171) which is greater than that of the interior space (4) « 14 · Gate valve according to one of the points 12 and 13, characterized in that the bearing clearance j = a. b, where a and b are constants, is. For this 9 pages drawings