A shut-off and regulating valve including a housing in which a valve disk is journaled for rotation, especially with double eccentricity. A metal seat ring is associated with a sealing surface of the valve disk. The seat ring includes an integral seat holding portion and has a radially deformable, resilient sealing lip. This sealing lip is permanently deformed radially outwardly by initial closure of the valve disk and contacts the sealing surface of the valve disk in a resiliently elastic manner. The valve has a simplified structure which exhibits improved sealing tightness and reduces the torque necessary to operate the valve.

BACKGROUND OF THE INVENTION 
This invention relates to a shut-off and regulating valve comprising a 
housing, a valve disk journaled in the housing, and a seat ring with which 
the valve disk can be brought into contact. 
U.S. Pat. No. 3,968,699 discloses a shut-off valve which has a seat ring 
with a resilient gasket for normal operation and, in case of damage, 
especially in a fire, a sealing lip of metal. This metal sealing lip is a 
component of a seat holding ring with which the seat ring is held in a 
chamber of the housing. The sealing lip has, in the unloaded state, 
essentially the same alignment as in the case of a closed valve disk. In 
the previously known shut-off valve the metal sealing lip by no means 
suffices to satisfy requirements with regard to the needed sealing action 
between the sealing surface and the valve disk, and a comparatively high 
leakage is to be expected. For the proper operation of the shut-off valve 
in normal operation, the seat ring of resilient material is absolutely 
necessary, the radial bias being applied by means of an additional 
resilient ring in order to satisfy the stringent requirements as regards 
sealing tightness and minimum leakage. The difficulty of manufacturing the 
previously known shut-off valve is therefore substantial. 
Furthermore, a check valve is disclosed in German Democratic Republic 
Patent No. 142,377, in which the valve disk is journaled in the housing 
with double eccentricity. In the housing a seat holding ring consisting of 
metal is fastened, which has a rounded seat surface for the valve disk. 
The rounded seat surface is a component of an annular internal portion of 
the seat ring, and the said internal portion is joined to the rest of the 
seat ring by a more or less radially aligned connecting piece. This 
connecting piece permits a certain elastic movement of the internal 
portion with the rounded contact surface when the valve disk is closed. 
The production of such a seat ring is very difficult because the 
manufacturing tolerances of various parts must be precisely coordinated 
with one another if sufficient sealing is to be possible. Also, when the 
seat ring is installed, the it must be precisely positioned with respect 
to the valve disk, and thereafter must be precisely secured in the housing 
by means of the additional seat holding ring. Such adjustment calls for 
the use of especially qualified personnel and involves appreciable cost. 
Finally, special measures must be taken to assure that the optimum 
positioning achieved with a certain probability during assembly will also 
be reliably maintained in the following period of operation. Even slight 
shifting of the seat ring due to the forces acting on it would have a very 
disadvantageous effect on the sealing and, in some cases, would call for 
quite difficult repairs. 
Furthermore, Japanese patent application 63-210,472-A discloses a safety 
valve which, again, has a sealing ring for normal operation made from an 
elastomer or a comparable nonmetallic material having a tongue which is 
aligned substantially radially. By means of an additional spring ring a 
radial bias is achieved with respect to the outside surface of the valve 
disk. In case of a fire, the seat ring has an additional sealing lip of 
metal with which the valve disk comes in contact. As explained above, such 
a metal sealing lip cannot produce a sufficient sealing in normal 
operation to satisfy the leak-proof sealing requirements which then apply. 
This is because comparatively high surface pressures between the seat ring 
and the valve disk would have to be anticipated, and this can result in 
disadvantages in regard to the service life and the materials that are 
used. To enable the required seal to be achieved between the spherical 
sealing surface of the valve disk and the seat ring, relatively high 
torques would have to be applied to open and close the valve. The driving 
means for actuating the valve would therefore have to be constructed 
sufficiently sturdily. 
SUMMARY OF THE INVENTION 
It is the object of the present invention to provide an improved shut-off 
and regulating valve. 
A further object of the invention is to provide a shut-off and regulating 
valve which exhibits an improved seal with a less complex manufacture and 
design. 
It is also an object of the invention to provide a shut-off and regulating 
valve which reduces the amount of torque required to operate the valve 
disk. 
Another object of the invention is to provide a shut-off and regulating 
valve in which the number of components required is reduced while assuring 
high reliability of operation and long service life. 
These and other objects of the invention are achieved by providing a 
shut-off and regulating valve comprising a housing, a valve disk journaled 
in said housing and having a sealing surface thereon, and a seat ring with 
which said valve disk can be brought into contact, wherein said seat ring 
is fastened directly in said housing by means of a seat holding ring 
portion which is an integral part of said seat ring, and said seat ring is 
provided with a radially deformable resilient sealing lip which engages 
said sealing surface of said valve disk under radial bias. 
The shut-off and regulating valve according to the invention is 
characterized by simple design and can be manufactured at considerably 
reduced cost. The metal seat ring is integrated with the holding ring and 
is thus made in one piece. In comparison with a separate seat ring, the 
special contact surfaces of the holding ring and housing for gripping the 
seat ring are eliminated. The seat ring integrated with the seat holding 
ring in accordance with the invention has a substantially simpler geometry 
which enables the machining and finishing time to be considerably reduced. 
The seat ring has a sealing surface which is produced by creating an 
annular relief groove in the seat ring. After it is made the sealing lip 
at first has an initial alignment with respect to the longitudinal axis 
and then is deformed plastically at a given angle and then assumes a 
second alignment with respect to the longitudinal axis. In the preparation 
of the seat ring and sealing lip, therefore, it is not necessary to 
satisfy any particularly stringent requirements regarding the shape of the 
sealing lip. 
No separate seat holding ring is necessary with respect to which the seat 
ring would have to be aligned in the housing. Instead, the seat ring and 
the seat holding ring form an integral unit in which the said sealing lip 
is likewise integrated. The sealing lip is made from the integrated seat 
ring, while observing the usual manufacturing tolerances and accuracy, and 
its adaptation to the geometry of the valve disks as necessary for a good 
seal and minimal leakage is achieved by plastic deformation of the sealing 
lip. In this manner minimum leakage is also assured even for normal 
operation, which in the case of the previously known shut-off valves was 
always achieved with an additional sealing ring of nonmetallic material. 
Due to the automatic adaptation and alignment of the sealing lip by the 
plastic deformation of the sealing lip proposed according to the 
invention, an excellent seal is achieved without the need to apply 
comparatively high torques to open and close the valve disk. Furthermore, 
high localized pressures, whether circumferential or axial, are reliably 
minimized by the plastic deformation of the sealing lip, thereby assuring 
a long useful life of the shut-off and regulating valve. 
After manufacture the sealing lip is substantially cylindrical, such that 
the cylindrical inside surface and/or the cylindrical outside surface are 
substantially coaxial with the longitudinal axis of the valve. The result 
is a considerable simplification of the manufacturing process since no 
complex tools and/or laborious working procedures are needed to produce 
the sealing lip and the relief groove. Instead, the relief groove as well 
as the sealing lip can be manufactured without difficulty using 
conventional machinery and tools. Upon closing, the resilient sealing lip 
is deformed radially within its resilient range and urged against the 
sealing surface of the valve disk. This results in contact of the sealing 
lip with the sealing surface under a radial bias over a comparatively 
large surface, and the specific surface pressure between sealing lip and 
sealing surface is appreciably reduced. 
Furthermore, the pressure of the medium present in the relief groove 
reinforces the radial sealing force in an especially desirable manner. The 
inside surface and likewise the outside surface of the sealing lip are 
made of a size corresponding to requirements. The pressure of the medium 
acts in an especially desirable manner radially and externally against the 
outside surface of the sealing lip, a slightly lesser radial component of 
force being active in accordance with the taper angle of the sealing 
surface of the valve disk. The sealing lip consisting entirely of metal, 
like the seat ring, is forced resiliently radially outwardly when the 
valve disk closes and is brought into contact with the sealing surface of 
the valve disk with a radial bias, thereby automatically compensating 
inaccuracies, tolerances and above all any axial shifting due to 
eccentricity, in an especially desirable manner. The sealing lip can best 
project with its edge axially to a given extent beyond the axial abutment 
or end face of the seat ring. The axial length of the sealing lip is by a 
given factor greater than the depth of the relief groove and the extent of 
its spring action can be adapted and can be specified according to 
requirements in an especially expedient manner by specifying the said 
length beforehand. 
Not until after the seat ring has been installed in the valve, is a plastic 
deformation of the metal sealing lip performed, especially by means of the 
valve disk, in such a manner that the sealing lip is similar to a taper in 
relation to the longitudinal axis. In this plastic deformation the sealing 
lip is precisely aligned with the geometry of the spherical sealing 
surface of the valve disk, thereby compensating manufacturing and 
installation tolerances in a virtually ideal manner, both in the valve 
disk and in the seat ring. Consequently the torque required for shutting 
and/or opening the flow path is substantially reduced. This self-alignment 
and adjustment of the sealing lip by means of the valve disk in accordance 
with the invention is especially important in such valves having eccentric 
or doubly eccentric valve disks. 
It is to be noted that, in doubly eccentric pivoting, the valve disk on the 
one hand is offset from the center line of the sealing ring and on the 
other hand is off-center from the longitudinal axis of the pipe. The 
sealing lip thus conically aligned furthermore has sufficient resilience 
so that, during operation, the sealing lip is in contact with a radial 
bias with the sealing surface of the valve disk in a reliably operating 
manner.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
FIG. 1 is a fragmentary axial longitudinal section through a housing 2 of a 
shut-off and regulating valve according to the invention. In housing 2, 
which has a longitudinal axis 4, a valve disk 6 is disposed for rotation 
about an axis 8. As can be seen from FIG. 1, axis 8 is perpendicular to 
the plane of the drawing and lies at a distance 10 off the center of the 
longitudinal axis 4. In the position shown, the valve disk 6 shuts off the 
flow of a medium, the direction of flow being indicated by the arrow 12. 
The broken line 14 indicates a sealing center line from which the axis 8 
has an offset 16. Valve disk 6 is thus arranged with a double eccentricity 
in housing 2. Valve disk 6 is provided on its outer circumference with a 
curved or rounded sealing surface 18 which is in sealing contact with a 
sealing lip 20 of a seat ring 22. The seat ring 22 is received in an 
annular recess 26 of housing 2 having a centering surface 19. The 
centering surface 19 is particularly designed as an annular cylindrical 
surface coaxial to the longitudinal axis 4. Centering surface 19 is in 
sliding contact with the corresponding outer surface 23 of seat ring 22. 
When the valve is assembled, the seat ring is simply placed in the recess, 
so that a definite alignment of the seat ring with the housing 2 is 
automatically achieved by means of the centering surface 19, and complex 
positional adjustments are unnecessary. 
The sealing lip 20 is an integral part of the seat ring 22 and is produced 
by creating a relief groove 24 coaxial to the longitudinal axis 4. The 
seat ring 22 is disposed in the annular recess 26 in the housing 2 and 
fastened directly to the housing, for example by means of screws which 
extend along broken lines 28. The radially outer portion 29 of seat ring 
22 is provided with bores 54 (Shown in FIG. 4) for the mounting screws and 
corresponds to the seat holding ring used heretofore. The seat ring 22 is 
integrated with the seat holding ring and made in one piece therewith. 
The sealing lip 20 made in one piece with the seat ring 22 engages the 
sealing surface 18 of valve disk 6 with radial bias. In contrast to prior 
art valves, the metal sealing lip 20 integrated into the seat ring 22 is 
the only seal, and there is no additional sealing ring of nonmetallic 
material as was common in conventional, prior art shut-off valves. This 
results in additional advantages in regard to the overall axial length of 
the shut-off and regulating valve. 
When the valve disk 6 is closed, the resilient sealing lip 20 is deformed 
within its resilient range and pressed against the sealing surface 18. The 
resulting radial sealing force is reinforced by the pressure of the 
medium, which is exerted in the relief groove 24 and produces a force 
component on the sealing lip 20 directed radially inwardly toward the 
longitudinal axis. 
A seal is produced between the housing 2 and the seat ring 22 by means of 
an annular gasket 30, which preferably consists of or contains graphite. 
The annular gasket 30 is disposed in an annular groove 32 in the housing 2 
such that an axial face 34 of seat ring 22 is in contact with the annular 
gasket. The other axial face 36 of the seat ring 22 lies in a common 
radial plane with an axial end face 38 of housing 2. 
In the closed position shown in FIG. 1, sealing lip 20 is conically aligned 
with the longitudinal axis 4 so that it forms a first angle 40 with the 
longitudinal axis. Depending on the nominal width of the valve, this first 
angle is between 25 and 10 degrees. Larger angles within this range are 
used for smaller nominal valve widths. For a nominal width of 80 mm it has 
been found advantageous to use an angle of about 21 degrees, and for a 
nominal width of 300 mm, an angle of about 13 degrees. 
A recess 39 is provided in housing 2 axially opposite the relief groove 24 
such that an annular clearance 41 exists between at the free end of the 
sealing lip 20 and the housing, so that the pressure of the medium will be 
exerted in the relief groove 24. The free end of sealing lip 20 extends 
part way into the recess 39 in housing 2. This results in advantages as 
regards the axial length of the valve. Even when the axial length of the 
sealing lip 20 is relatively large, there is no need to increase the 
length and/or the size of the valve. 
FIG. 2 shows the valve disk 6 in a partially opened position. As it can be 
seen, due to the doubly eccentric mounting of the valve disk 6, its 
sealing surface 18 is still in contact with the sealing lip 20 in the 
upper part of the drawing, while in the lower part of the drawing sealing 
surface 18 is already out of contact with the sealing lip 20. When the 
valve disk 6 is in the open position, the sealing lip 20 forms a second 
angle 42 with the longitudinal axis 4, which in accordance with the 
invention is smaller than the aforementioned first angle 40. This second 
angle 42 ranges between 23 and 8 degrees of angle, again depending on the 
nominal width of the valve. For a nominal width of 80 mm, this second 
angle 42 is advantageously about 19 degrees, while for a nominal width of 
300 mm, it is about 12 degrees. In accordance with the angular difference 
from the closed position shown in FIG. 1, when the valve is closed, the 
sealing lip 20 is biased radially against the sealing surface 18 of valve 
disk 6. A good sealing action is achieved by this radial, resilient bias, 
which is additionally reinforced by the pressure of the medium in the 
relief groove 24. 
FIG. 3 shows the seat ring 22 with the integrated sealing lip 20 in the new 
state, i.e., before installation in the housing. By the formation of the 
relief groove 24 in the seat ring 22, the sealing lip 20 was initially 
produced with a substantially rectangular cross section having a 
cylindrical inside surface 44 and a cylindrical outside surface 46. 
Although the arrangement of the inside surface 44 and outside surface 46 
as cylindrical surfaces has proven especially desirable from the 
manufacturing point of view, the inside and outside surfaces can also 
assume a different orientation with respect to the longitudinal axis 4, as 
is generally indicated by the line 45. 
It is essential to all embodiments that, beginning with the production of 
an initial orientation of the sealing lip 20, a permanent deformation at a 
given angle 47 is performed thereafter. This results in optimum adaptation 
and equalization of manufacturing tolerances, so that during the actual 
manufacturing less emphasis needs to be assigned to achieving close 
manufacturing tolerances. Furthermore, after seat ring 22 is installed in 
recess 26 of housing 2 during assembly of the valve, no additional 
adjustments need be made, inasmuch as the outside surface 23 lies against 
the associated centering surface 19, and conventional tolerances for a 
sliding fit should be observed. On account of such sliding fit the seat 
ring 22 can be inserted without difficulty into the associated recess in 
the housing, and then all that remains to be done is to fasten it in the 
housing. For this purpose no additional seat holding ring is necessary, 
and the seat ring is fastened in place in a direct and uncomplicated way 
by means of screws or the like. 
After installation in the housing, a permanent shaping of the sealing lip 
to the second angle 42, described above with reference to FIG. 2, is 
performed by operating the valve disk. This permanent deformation is 
substantially greater than the resilient deformation of the sealing lip 20 
during operation. The orientation of the sealing lip 20 after manufacture 
to the line 45 and the establishment of the angle 47 for the plastic 
deformation of the sealing lip 20 are performed according to the 
particular requirements, giving foremost consideration to the nominal 
diameter of the valve and the properties of the material of the seat ring 
22. 
The above-mentioned plastic deformation of sealing lip 20, which is made of 
metal, can also be performed in several steps if desired, particularly in 
the case of the larger valve diameters. Thus a part of the necessary 
plastic deformation can be performed before the seat ring is installed in 
the housing, so as to minimize the deformation that is to be performed by 
the valve disk in accordance with the invention. This makes it possible, 
especially in the case of the larger valve diameters, to avoid 
unacceptably great stresses on the valve disk, and especially on its 
bearings. On the other hand, it has proven to be desirable, especially in 
the case of small valve diameters, to perform the entire deformation with 
the valve disk after the seat ring is installed. 
The seat ring 22 with the integral sealing lip 20 can be produced without 
any special difficulty. In particular, there is no need for extreme 
accuracy regarding the geometry of the sealing lip. Neither is there any 
need for any reworking of the sealing lip, for example to adapt it to the 
spherical sealing surface of the valve disk. Due to the permanent 
deformation of the sealing lip 20 by means of the valve disk after the 
shut-off and regulating valve has been assembled, manufacturing 
inaccuracies and the like are compensated for in an especially 
advantageous manner, with the result that, on the one hand a very good 
sealing action is achieved, and on the other hand the torque required for 
closing and opening the valve disk is substantially improved compared to 
prior art designs. Furthermore, it is especially significant that the 
sealing lip does not need to be machined to correspond to eccentric or 
doubly eccentric mounting. Instead, the necessary geometric adaptation 
that is needed in this regard is performed automatically by the permanent 
deformation, in particular after installation. 
The seat ring 22 and thus also the sealing lip 20 have a modulus of 
elasticity in the range from 150 to 230 kN/mm.sup.2, a modulus in the 
range between 170 kN/mm.sup.2 and 200 kN/mm.sup.2 having proven especially 
effective. 
As can be seen from the enlarged representation in FIG. 4, the relief 
groove 24 has an axial depth 48, while the sealing lip 20 has an axial 
length 50. In one preferred configuration, the axial depth 48 is between 4 
to 6 mm and amounts to about 5 mm. The free end 49 of the sealing lip 20 
extends axially by a given factor beyond the contact surface or axial end 
face 34 of seat ring 22. The length 50 of the sealing lip 20 is larger by 
a given factor than the axial depth 48 of the relief groove 24. The 
magnitude of the radial bias force is definitely established in an 
especially desirable manner by the free length of the spring action of 
sealing lip 20. The length 50 of the sealing lip 20 ranges between 4 and 8 
mm, and is preferably from 5 to 7 mm. The radial thickness 52 of the 
sealing lip 20 ranges between 0.7 and 1.8 mm, and preferably is about 1.0 
to 1.5 mm. 
One of the holes 54 for fastening the seat ring 22 in the housing is shown 
in the radially outer part 29 which corresponds to the holding ring. 
The foregoing description and examples have been set forth merely to 
illustrate the invention and are not intended to be limiting. Since 
modifications of the described embodiments incorporating the spirit and 
substance of the invention may occur to persons skilled in the art, the 
invention should be construed to include all variations falling within the 
scope of the appended claims and equivalents thereof.