Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
~33~8
he invention relates to shut-s~f pipeline fittings,
and more specifically it deals with a gate valveO
A gate valve according to the invention ma be most
efficiently used in pipelines intended for conveying sus-
pe~ded abrasive materials/ preferably slurries.
The invention may be used in the mining, c~n~truction
and chemical industries and also it other industries employ
ing bydraulic and pneumatic conveyance ox fluids in the
form ox suspensions and slurries containihg solid partic_
les, especially of fluids which cause a highly intensive
wear of the seat and gate which should be replace during
operation
now in the art is a gate valYe, comprising a cawing
having a passage. A gate is accommodated in the casing and
a seat is installed in alighment with the centerline ox
the passage (cf. ~SS~ Inventor's Certificate ~o.45092~,
Cl. F 16 k ~f14, F 16 k 3/~0, Nova 25, 1974).
Two stops are installed transversely ox the ce~terli-
ye of the passage, the stops eDgaging with their tapered
surfaces tapered faces of the gate provided on the gate
side opposite to the wide thereof facing toward the seat,
when the gate is in the closed position.
he stops ara disposed so that each stop is locatad
on the side of the gate opposite to the side therao~ fa-
cing toward the teat 3 and adjacent to the side surfaces at
the level of the passage centerline.
- 2
~33~
The tapered surfaces are provided ox the side of the
gate opposite to the side t~lereo~ ~aci~g toward the seat
and make an acute ankle with the direction of movement of
th6 gate into it shut-off position,
'iVhen -the stops engage the tapered surfaces of the
gate, they urge the gate cast the end race of the seat
racing toward the gate thus ensuring the sealing when the
passage it shut-of~.
For tightly pressing the gate against said end race
of the seat arid for ensuring the tightl;y sealed shutting
-off of the passage, the tops should accurately mate with
said tapered surfaces.
It the prior art gate valve the stops are rigidly
secured to the end fa¢e of rods accommodat ed in the casing.
Mach rod is installed in a hole of a casing wall along an
axis extending transversely of the centerline of the passa-
ge for a limited rotation abollt its agis.
As a result of a rather rapid wear of said seat and
gate during operation of the gate valve with abrasive slur-
ries, the distance from the end face of the seat facing
toward thy cooperating surface to the surface of the stops
e~gagi~g the tapered faces of the gate should be adjusted
jot unfreque~tlY~
In the prior art gate valve the end face portion ox
each rod racing toward the passage is made in the form ox
a step wormed by cutting~off the cylindrical part ox the
rod to one half ox its diameter.
3 --
33
The stop is secured to the slat faces of the step
facing toward the seat 9 and a set of thin spacers are ins-
talled between this surface of the step and the surface of
the stop coin toward this surface.
By varying the number of the spacers and thickness ox
said set the diskance from the surface of the seat facing
toward the gate to the stop surfaces e~agi~g the tapered
races of the gate may be adjustedO
he amount ox rotation of each rod is determined by
clearances between the end of a rigidly secured pin protrud-
ing Yrom the casing and the wall of a groove made in the
rod.
Owing to a limited rotation of the rods about their
a~es~ the rods intimately engage said tapered faces ox the
gate with their surfaces engageable with the tapered faces
of the gate thereby compeDsati~g for ma~ufacturi~g tolera~-
ces of angles of taper
the the prior art gate valve is ussd~ the abovedescrib-
ed adjustment of the distance from the surface of the seat
racing toward the gaze to the sur~ace~ of the stops enga-
geable with the tapered faces of the gate by varying the
umber of spacers and thickness of the set of spacers is
di~icult because the rod with the tops secured thereto
should be withdrawn from the casing which i3 only possible
after the disconnection ox the pipeline thus impairing
the cost-ef~ectivenessO
In addition, thin spacers which are normally used in
., Lo _
~33~
the stops have rather short service live because of cor-
rosion 9 specially when the gate valves work with abrasi-
ve and aggressive fluids
~ummaxy ox the Invention
The invention is based on the pxoblem oY providing
a gate valve wherein the stop is installed in such a
manner as to enable the adjustment of the distance from
the surface of the ssat facing toward the gate to the sur-
faces of the stops engageable with the tapered fact of
the gate on the operating pipeline without wi.thdrawing
the stops from the valve casi~g~
This problem is solved by that in a gate valve, comp-
rising a casing in which are accommodated a gate, a seat
aligned with the centerline ox a casing passage, and at
least one stop e~ageable, when the gate is in the shutoff
position, with at least owe tapered race ox the Nate provi~
ded on the gate side opposite to its side facing toward
the seat in the direction ox its movement to the shut-
-off positio~7 the top ~ei~g rigidly secured to a rod ins-
talled in the casing along an axis extending transversely
ox the centerline of the passage or rotation about this
axis 80 as to engage at least a part ox the end race ox
the rod facing toward the centerline of the passage, ac-
cording to the invention, there is provided a sleeve ins
talled in a cawing wall or rotation relative thereto
tha inner surface ox the sleeve being coaxial with; and
surrounding the stop rod, and the longitudinal centerline
-- 5 --
ox t'ne outer surface of the sleeve being ecc~n-trical with
resQect to the longitudinal axis of the rod.
he installation of the rod to which is secured the
stop in the sleeve installed in the casing wall and having
the inner surface coaxial with the stop rod and the lon-
gitudinal centelline of the outer surface offset with
respect to the longitudinal axis ox the rod makes it pos-
sible to adiust the distance from the end face of the seat
facing toward the gate to the surface ox the stop incli-
ned with respect to the gate by rotating the sleeveg De-
pending on the direction of rotation of the sleeve, the
surface of the stop which is inclined with respect to the
gate will either move closer to the end face of the seat
facing toward the gate or away therefrom thus varying said
distance owing to the eccentricity of the outer surface
of the sleeve with respect to the longitudinal axis ox
the rodO
'this construction of the gate valve makes it possib
le to adjust the distance from the end face of the seat to
the surfaces of the stops facing toward the seat on the
operating pipeline, without withdrawing the stops and rods
from the casino- thus substantially saving labour effort
and time.
The gate valYe preferably has a pin rigidly secured
to the rod, extending transversely of the longitudinal
centerline ox the rod and passing freely through the slee-
ve, the end of the pin being freely received in the casing
-- 6 --
~23;3~
having or tnat purpose grooves open to~lard the sleeYe
for receiving each end of the pin, the side walls of the
groove limiting the displacement of the pin ends when
the tapered face of the gate en~a~es the stop, and the
sleeve has two radially extending through holes having a
angular extent equal to a maximum amount of rotation of
the sleeve.
he provision ox the abovedescribed pins limits the
angle of rotation of the rods within a predetermined range
and eliminates an inadvertent rotation ox the stops under
the action of the pipeline vibrations or my virtue of
other factors toward the seat thereby preventing an
cause which might result in a damage to the stops and impro
ving the reliability of the gate valve.
Owing to the provision of the radially extending
through holes in the sleevo; the pin, which is rigidly ye-
cured to the rod, does not prevent the sleeve from being
rotated over a angle required or the adjustment.
The eccentricity is preferably such that its ratio to
the outside diameter ox the sleeve should not be in excess
of one-half of the coefficient of friction between the
sleeve and casings
This facility prevents the sleeve prom inadvertently
rotating under tho action ox external factors and elimina~
ten the undesirable change in the distance from the seat
surface facing toward the gate to the surface of the stops
engageable with the tapeIed faces of the gate.
-- 7 --
~23~
The sleeve preferably has on the end face side op-
posite to the side Yacing towald the gate a portion prot
IUding outside the casing, said portion being adapted to
take-up a force causing rotation ox the sleeve.
he provision of the portion protruding outside the
casing facilitates the employment of tools (levers; wren-
eke and the like) for Turin the stop it the desired
direction in performing the adjustment operations.
Annular members made ox a wear-resista~t material
are preferably rigidly secured to the surfaces of the
seat and gate engageable with each other when the gate
is it the shut-off position
This facility prolongs the service live of the seat
and gate which is especially important with the abovedescri-
bed cons~ructio~ of the gate valve wherein a tight enga-
geme~t of the gate and seat is ensured when the gate is in
the shut of position which in certain applications might
otherwise result in rather strong wear of the gate and
seat.
he axis of the a~ular member cured to the seat
is preferably offset with respect to the axis of the seat
so that the annular member should be offset in the direc-
tio~ of movement of the Nate when the gate is moved into
its shut-o~f position.
This oilily results in that the working surface ox
the teat is disposed outside the zone of action of abrasive
particles which are pres0nt in thy, flow so as to prolong
the service life ox the gate valve
-- 8 --
9L~3~
The gate valve according to the invention enables
the adjustment of the distance from the surface ox the
seat racing -toward -the Nate to the surfaces of the stops
e~a~eable with -the tapered faces ox the gate on the ope-
rating pipeline, without withdrawing the stops prom the
valve casi~g~
In addition 9 the gate valve according to the inven-
tion has comparatively long servico live, it is reliable
and convenient in operation.
he invention will now be described in detail with
reference to the accompanying drawings illustrating a spe-
cific embodime~t~
Brief Description ox the Dxawings
Figure 1 schematically shows a gate valve according
to the invention7 it a lo~itudinal section;
Figure 2 is a sectional view taken alosg the line
II in Figure 1;
Figure 3 is an enlarged detail it P`igure 2;
Figure 4 is an enlarged sectional view taken along
the live IV-IV ir. figure 3;
Figure 5 schematically shows a seat, a part of a
gate, and a stop; vectors of forces between the gate and
stops are also show on the enlarged scale;
igure 6 schematically shows a enlarged view of a
seat, a part ox a gate, and a stop in longitudinal section
when tapered face ox the gate are made with a deviation
of their a~gl.e ox -taper toward the stops;
Figure 7 is ditto, with the gata tapered races made
with their angle of' taper in the direction away from the
f 1~ CJ
~2 ~3
FiOure 8 schema-tically shows an enlarged view, in
longitudinal section, ox a paIt ox a gate and a stop when
the gate thickness deviates from a preset thickness; the
gate in the shut-o~f position and the respective position
ox the stop are shown with dotted lines,
Figure 9 schematically shows an enlarged view, in
lonOitudinal section, ox a seat and a part of a gate at
the beginning ox the gate movement into its open position.
he Preferred Embodiment ox the Invention
A gate valve according to the invention comprises a
casing 1 (figure 1) having a passage 2 for a fluid contain-
ing solid abrasive particles, in particular, a slurry.
he passage 2 extends in the casing 1 along its longi-
tudinal centerline 3.
The casing 1 has substantially over its whole h0ight
a configuration of` a cylinder with a centerline extend-
ing at right angles to the centerline 3. A end plate 5
shaped as a part of a sphere is secured at the top to a
Lange (without re~ere~ce) of the casing 1 by means ox a
Lange (without reference).
Cylindrical butt pipes 6 integral with the casing 1
are provided in alig~men~ with the centerline of the
passage 2 of the casing lu
the butt pipes 6 are designed for connection
to a pipeli~ (not shown through which a slurry from a
source (not shown) is to be co~veyed~
- 10 -
~2 ~3~
Tb~ lower wall Do the casing 1 is of a bent c~nfigu-
ration at a point adjacent to the centerline 4 as desert
bed it detail belDw.
A ga5e 7 is installed in the casing 1 along the cen-
-terline 49 and the Nate is opera-tively connected to a dri-
ve 8 by means of a rod 9 extending thrDugh a hol0 (without
reference) in the end plate 5 along the cent0rline 4 as
shown at the top of Figure 1a
The drive 8 ma be o-f any appropriate known type,
and this drive will not be described in detail herein
because it has no bearing on the inventionO
seat 10 is tightly fitted in the casing 1, in a
socket (without reference) made for that purpose in a pox-
tiDn of the casing protruding inwardly the seat being
aligned with the centerline 3. the side of the gate 7 fa-
cing toward the seat 10 has an annular projection 11 defin-
ing a working surface ox the gate 7, also designated
at 11, which is designed for an intimate engagement with
an end face 12 of the seat 10 facing toward the gate 7,.
which it hereinaft0r referred to as the working surface 12.
A surface 13 of the gate 7 w~icb i5 opposite to its
working surface 11 is flat in the top part of the gate 7 as
shown in Figure 1 and extends at right angles to the cen-
terline 3 7 and the lower part of thy surface 13 of the
gate 7 has an extension .in the form ox a tapered face 14
which makes an acute angle cC with a vertical plane per-
pendicular to the centerline 3 it the directiDn Df movement
of the gate 7 into its s~ut-off position.
,
~11-
~33~
'the cross-sectional area of the upper part ox the gate
7 is ~;reateI than the cross-sectional area of its lower
part.
The inner sur~ac~ of the lower part of the casing 1
below the Nate 7 has a cylindlical portion 15 which is
spaced from the tree end ox the gate 7 when in the shut-
-off position.
The cylindrical portion 15 is conjugated with a ta-
pering portion 16 which is conjugated v~ith the ten sur-
face ox the righthand butt pipe 6 as shown in ~}gure 1.
Owing to the provision ox the tapering portion 16 of
the east 1, solid particles present in a fluid conveyed
through gate valve and settling below the gate 7 are cau-
sed to move by the tapered face ox the free end ox the
gate 7 into the righthand butt pipe 6 as shown in Figu~ 1
without hampering the complete shutting-off of the passa-
ge 2 of' the casing 1.
The casing 1 has two cylindrical stops 17 engagea~le
with thy tapered race ~4 when the gate 7 is in the shut-
-off position.
he stops 17 are spaced from each other ox the side
of the tapered race 14 of the gate 7, adjacent to side pa-
ces 18 ox the gate (Figure 2) at the level with khe cen-
terline 3 of the passage 2.
ach stop i8 rigidly secured by a known means to
a rod 19 which is installed in the casing 1 transversely
ox the centerline 3 of the passaKe 2 f'or a limited rota-
tion about a axis 20 of the rod 19, together with thy
rod 19~
12 -
ach stop 1~7 enrages a part of a end face 21 of the
rod 19 facing toward the centerline 3/ of the passage ED
A periphery 2Z (Figure I) o.~ the stop 17 is it the
form of a half-cyli~der, and the outer suLface of the stop
is an extension of the cylindrical surface ox the rod 19.
A part of the surface 22 of the stop 17 facing to-
ward the Nate 7 is flat and is inclined alto at an acute
angle O with respect to a vertical plane perpendicular
to the centerline 3 of the passage 2 (Figure l
Sleeves 23 (Figures 2 and 3) are provided in thy ca-
sing 1, each sleeve surrounding a respective rod 19. Mach
sleeve 23 is installed in a respective through hole (wi
thout reverence) of the wall of.the casing 1 for rotation
relative to the casing 1.
The inner surface 2~ (Figure 3~ 4) of the sleeve 23
is coaxial with9 and surrounds the rod 19.
he outer surface 25 of the sleeve 2~ Yates with the
surfaces of the through hole in the wall ox the casing 1.
The mating surfaces 24 and 25 of the sleeve 23 are
sealed with respect to corresponding mating surfaces of
the rod 19 and casing 1 by means ox seals 26 and 27 which
may be of any appropriate known ape (figure 3).
The lo~gitudi~al centerline ox the outer surface 25
ox the sleeve 239 the projection of which on the plane of
the drawing it Figure 4 it designated as a point 28, i3
offset with a eccentricity f with respect to the axis
20 ox the rod 19 (Fi~ura 3) which is shown as the point ?0
in Figure 4,
-- 13 -
~33~
his construction makes it possib:Le to adjust the
distance "B'l (Figures 1 and 3) from the end face 12 of
the seat 10 facing towa:rd the gate 7 to the flat surface
ox the stop 17 by rotating the sleeve ~3 about its longi-
tudinal centerline shown as the point 28 in figure 4.
This facility enables the adjustment of the distance
"Bll upon replacement of the seat 10 and gate 7 without
removing the casing 1 from the pipeline, and any fitting
operation during installation of a new set of the seat 10
and gate 7 may be dispensed with.
pi 29 (Figures 3 and 4) is provided which is ri-
gidly secured to the rod 19 and extends at right angle
to the axis 20 ox the rod 19.
he pin 29 passes freely through the sleeve 23 and
has its ends freely received in the casing 1. For that
purpose grooves ~0 open toward the sleeve 2~ are made in
the casing for each end ox the pin 29.
Side walls 31 (Figure 4) of the groove ~0 of the ca-
sing 1 are designed for limiti~ the displacemert when the
tapered ace 14 of the gate 7 engages the stop 17,
The sleeve 23 has two radially e~te~ding through
holes 3~ respectively, fvr a tree passe therethrough of
the ends of the pin 29.
The annular extents ox the holes 32 are equal to
maximum angles ox rotation of the sleeve 23.
The pins 29 retain the stops 17 rigidly secured to
the rods 19 at an angle which is equal to the angle of
- 14
~23~
taper ox the tapered face 14 of the gate I, and the tree
ar.rangement of -the ends ox the pins 29 in the groove 30
ox the casing 1 allows to the sur~ace.s of the stops 17
to align against the tapered face 14 of the gate 7 thus
compensating or a ~lanufacturing tole:ra~ce of the angle a
ox taper of the tapered race 14 which is imposed it ma-
king the gate 7.
Ow-ing to the provision of the radially extending
through holes 32, the yin 29 does not prevent the sleeve
2~ prom rotating when the adjustment operation is perfor-
Ed
he eccentricity " " is such that the ratio ox the
eccentricity to the outside diameter of the sleeve 23 "I"
is not in excess of one-half of the coefficient ox Eric-
tio~ 'I " between the sleeve 23 and the casing 10
In this case as show in Figure I, the force "C"
of pressure OI the tapered face 14 of the gate 7 applied
at a point 33 at which the centerline intersects the
tapered race 14~ is spaced from the point 28, which is the
pro jection ox the longitudinal centerline ox the outer
surface ox the sleeve 23 on the drawing plane, at a distant
ce equal to the eccentricity l
statical equilibrium of forces O " and "C " equal
to the force "C" and directed oppositely to owe another
occurs at the point 28, the couple of forces "CC " results
it a mo~en-t Of thigh tends to turn the sleeve 23 coun-
terclo~kwise so as to increase the distance "B" thus ten-
dip; to unseal the gate valve.
~15
3~
At the same time, the force "C tll thigh is equal to
the force "C1', urges the outer suIface 25 of the sleeve
23 against the wall 34 (Figure 5) of -the hole in the ca-
sing 1 provided for thy sleeve 23 thereby creating a fric-
tion force "F" which is equal to a pxoduct ox the force
"C" = C by the coefficient of friction "I' between
the sleeve 23 and the wall of the casi.ng 1.
he friction force "F" acts with an arm equal to one-
Hal of the diameter "I" of the outer ~ur~ace 25 of the
sleeve 2~. As a result ox the action of the force "C" a
moment "M"' of friction (not show) is applied which is
equal to a product of the friction force "I" by o~e~half
of the diameter "D". In order to prevent -the sleeve prom
inadvertently rotating about its longitudinal centerline,
it is necessary that the inequality I'>, M be complied
with, i.e. Do
With the ratio of the eccentricity "I" to the diame-
ter "D" ox the sleeve 2~ smaller than one-hal~ ox the coef
ficient of friction " the sleeve 23 is retained its
inadvertent rotation is prevented, and tne conditions for
sealing of the gate valve are ~mproved~
On the end race side opposite to the side thereof
racing toward the gate 7, the sleeve 2~ is held against
axial movement by a rotating ring j5 (Figure 3) which
is installed in a annular groove (without reference) ox
the casing l and the sleeve 2~ has a pOItiO~ 36 protruding
outside the casing 1 for taking-up of a foxce applied or
rotation of the sleeve 23.
16
3L2~
The protruding portion 36 ha a cylinarical periphery
(wi.thout reference). A hole 37 is made in the protruding
portion ~6 to extend thxough the lon~itudi~al centerline
of the outer suu~ace 25 of the sleeve 23, at right angles
thereto.
'the hole 37 is designed or receiving a lever (not
shown) to which is applied a force fox lotating the sleeve.
This facilitates rotation ox the sleeve 23 in making the
adjustment.
To prevent the gate 7 and seat 10 prom being worn
upon a intimate engagement of their surfaces under the
action ox the stops 17~ annular members 38 and 11 (Fi-
gure 1) are rigidly secured to the surfaces of the seat 10
and gate 7 engaging each other when the gate 7 is in the
shut-off position, the annular members being made of a
wear-resistant material and de~i~i~g projections ox the
set 10 and gate 7, having working surfaces 12 and 39,
respectively
Owing to the provision ox the annular members 38
and 11 made of a wear-resistant material the service life
of the data 7 and seat 1Q engaging each other is prolonged.
The annular member 38 is rigidly secured to the sur
race of the seat 10 in a offset position, with an o~'~se~
in the direction ox movement of the gate 7 when the gate
i8 moved into the shut-o~f position Jo that a crescent-
-shape recess 40 is defined adjacent to the working sur-
face 12 ox the seat 'lO (figure 9), which is formed by arcs
- 17 -
~2 3~
of circlas of the cross-secti~ of toe passaOe 2 and the
inner surface of th0 annular member 38~ This construction
of toe seat 10 allows the lower part of the working
surface 12 of the seat 10 to be dlspDsed outside the zone
of the mainstream of the fluid flDw, which migbt otherwise
be subjected to the action vl coarsest and most abrasive
sDlid particle presen-t in the flow which are fDrced under
gravity to the lower boundary of the flow. the service
live of the working surfacss ox the sea 10 and gate 7
is thereby further prolonged
The gate valve according to the invention functions
in the following mannerO
Under tbe action of the drive 8 thy rod 9, connected
to the drive, tarts reciprocating along the centerline 4
of the casing 1 and causes the movement of the gate 7
connected to the rod 9.
When the gate 7 moves upward in Figure 1, the working
surface 39 of the annular projection 11 cf the gate 7 dis-
engages from the working surfaee 12 of the seat 10 and
opens ths passage 2 Df the casing 1 for the passage the-
re~hrough of a fluid being conveyed.
When the gate 7 moves downward in figure 1, the wor-
king surface 39 of the annular projection 11 Df the gate 7
engages the working surface 12 Df the seat 10 and shuts-
-of the passage 2 of the casing 1.
The tapered face 14 of the gate 7 m~ki~g an acute
angle " a 1I witb a vertical plane perpendicular to the cen-
-18-
3~
terline 3 of the passage 2 engages the slat surfaces 22
of the stops 17 which are also inclined at an acute angle
at to a vertical plane perpendicular to the centerline 3
of the passage 2. When the tapered f'ace 14 engages the
fat surfaces 22 of the stops 17, the working surface 39
of the annular projection 11 of the gate 7 is urged against
the working surface 12 ox the seat 10 thus ensuring the
sealed shutti~g-o~ of the passage 2.
Solid particles of the fluid being conveyed thus get
beneath the free end of the gate 7 and are caused to move
under the action of the free end of the tapered face 14 ox
the gate 7 along the tapering portion 16 ox the casing 1
into the righthand butt pipe 6 in Figure 1, without hamper-
ing the movemeut of the gate 7.
In case ox deviations ox the angles of taper a of
the gate 7 and stops 'l7 as a result of manufacturing to-
lerances in making the gate valve, e.g. by an angle
(figure 6) the gate 7 moving downward, short ox its lower-
most position, engages with its tapered race 14 with the
slat surface 22 ox the 5~0p 17 facing toward the gate 7
only along the lower line shown by a point 41 in Figure 6,
rather thaw o'er the whole surface. the positions of the
lower end ox the tapered face 14 ox the gate 7 and the
surface 22 of the stop 'l7 at the moment ox engagement
along toe live corresponding to the point 41 are shown
with dotted lines it Figure 6,
During further downward movement of the gate 7 its
tapered face 14 urges the end ox the slat surface 22 ox
- 19 -
~3~
the stop 17 to the I`i ' ht in Figure 6 and causes its ro-
tation countelclockwise about the axis 20 ox the rod 19
50 that when -the gate 7 is in the lowermost position the
flat surface 22 is in colnplete engagenent with -the tape-
red f'ace 14 of the gate 7 as shown with solid lines it
Figure 6
he pin 29 a].so rotates counterclockwise through a
angle " I" from the position shown with dotted line to a
position shown with solid line. As one-half of the angular
exten-t ox each groove 30 of the casing 1 is equal to an
angle "I ", which is greater than the angle "I " equal
to one~half of tha manufact~ing tolerance for the gate 7,
the groove 30 hampers rotation of the stop 17 over the
angle " ".
As the angular extent 'I " of the radially extending
through holes 32 ox the sleeve 23 is much greater thaw
the angle "cC", the sleeve 23 also does not hamper rotation
ox the stop 17 rigidly secured to the rod 19 about the
axis 20 of the rod 19.
Therefore the slat surface 22 ox each stop 17 is po-
sitioned9 and i~imately engage the tapexed face 14 of
the gate 7, Jo as to tightly urge the working surface 39
ox the annular pro jectio~ 11 of the gate 7 against the
working surface l of the seat 100
It the angle ox taper a ox the tapered race 14 of
the gate 7 deviates in the direction opposite to thaw
shown in Figure 6, as shown with dotted line9 the tapered
- 20 -
~33~8
face 14 engages the flat surface 22 ox each stop 17 alongthe line show my a point 42 it Figure 7 and causes its
rotation clockwise with the result that in the lower-
most position of the slat surface 22 this surface intima-
tely. ongages the tapered face 14 ox the gate 7 so as to
tightly urge the working surface ~9 ox the annular pro-
jection 11 of the gate 7 against the working surfaca 12
of the seat 10~
Thus a tight sealing in shutting-o~ the flow ox a
fluid being conveyed is ensured.
The self-alignrnent ox the flat surface 2~ ox each
stop 17 improves the cost-effectiveness of the gate valve
owing to a lower labour effort for the manufacture ox the
gate 7 since a rather labour-co~suming manufacturing pro-
cess associated with the fitting ox the angle ox taper 1l~ 17
of the tapered ~ac~ 14 of the gate 7 to the angle of incli-
nation of the flat surface 22 of each stop 17 may be dis-
pensed with.
Deviations ox the distance "B" prom the surface 12 of
the seat 10 to the flat surface 22 of the stop 17 may occur
during manu~acture~ the distance "B" is equal to the dime
sion~ ox the gate 7, namely to its thickness as shown it
Figure 1 along the centerline 3 when the gate 7 is in the
shut-o~f position
The dimensiQns ox the gate 7 may be equal to "B1"
(Figure 8) which is greater than the distance "B", or
"B2" (jot shown) which it smaller than the distante "B"~
- Z1 -
~23~5~3
If the dimenslon "B1" of the gate 7 is treater than thedistance "B", the gate 7, will stop short ox its lowermost
position, and in this case the working suI~ace 39 of the
annular projection 11 ox the gate 7 will not engage the
working surface 12 of the seat 10 so that the slow will
not be shut-of~ with a desired tightness.
r~his may be remedied by rotating the sleeve 23 in the
direction shown by arrow "G". the point 33, which is the
center of the cross-section ox the stop 17 transversely
of the axis 20, rotates counterclock.~ise about the point
28 along a circle of a radius "R" as shown with a dash-
-a~d-dot line in figure 8. The stop 17 will thus move
along the centerline 3 ox the passage 2 as shown by arrow
"H" so as to enlarge the distance "B7'~ 'the sleeve 23 is
rotated until the distance "B" becomes equal to t'B1" and
the stop 17 is in the position shown with dotted line in
Figure 8.
fter this adiustment the gate 7 will be in the posi-
tion show with dotted line in Figure 8 wnen in thy
shut-of~ position thereby providing for a tight shutting-
-of of the passage 2.
he the dimension "B2'i of the thickness of the gate 7
is smaller thaw the distance "B", the sleeve 23 is rotated
cl.ockwise in the direction opposite to that shown by arrow
c The stop 7 will then move along the center1i~e 3 of
the passage 2 to the left in figure 8 so as to reduce
the dimensions "B" to the value of "B2"- This provides
22 -
I% 33
for a tight shuttingr-off of the passage 2 when the gate 7
it in the shut~o~f position.
Owing to the adjustment of the distance "B" by
meats of the rotatable sleevl~ 23 a rather labour-consum-
ing operation of ~ittin~ the thickness of each gate 7
to a distance "B'l from each stop 17 to the working
surface 12 of the seat 10 ma be dispensed with
ith a minor opening ox the passage 2 between the
seat 10 and gate 7 at the beginning of the opening opera-
tion or at thy end ox the shutting-off the flow of fluid
passing through such clearance 4~ (~'igure 9) in the passa-
ge 2 as shown by arrow "J" has increased velocities owing
to the restriction. In view of higher velocities the wear
of' the working surfase 12 ox the seat 10 and working sur-
face ~9 of the gate 10 may be accelerated. This may cause
a premature failure of the abovementioned working surfaces
and shorter service life ox the ~alveO
The service life of the working surfaces 12 and 39
in the gate valve according to the invention is prolonged
because these surfaces are defined on annular members 11
and 38 made ox a ~ear-resistant material and rigldly secu-
red to the gate 7 and seat 10. The offset position of the
annular member 38 of the seat 10 in the direction ox move-
met of the gate 7 when it is moved into the shut-off po
sition also contributes to the prolongation of the service
life. Owing to this facility 9 the woIking surface 12 of
the seat 10 is arranged outside the zone ox action ox the
- 23 -
mainstream abrasive flow directed along arrow 11JIl, andthis abrasive action is ta~en-up by the end face 44 of
the crescent shaped recess 40 of the working surface 12 ox
the seat 10 that doe not participate in -the sealing of
the passage 2.
Thus the woIking surfaces 12~ ~9 of the seat 10 and
gate 7~ respacti~ely, are protected against the wear by
the abrasive flow, and their service live is prolonged
The use of the invention improves the cost-ef~ective-
ness of the gate valve in the manufacture owing to the
elimination of rather labour-consuming fitting operations,
makes it possible to ensure a desired tightness of sealing
in using the production equipment ox lower accuracy.
In addition9 the assembly of rapidly wearing parts of
the gate and seat Jay be performed directly on the pipeline
without their fitting to the casing (when these parts are
replaced during operation) thus lowering the operation
cost.
he service live ox the gate valve is also prolonged.
The Nate valves manufactured in accordance with the
inve~ion feature an improved cost-effectivene~s in the
manufacture, convenience in maintenance and repair and
prolonged service life in operation in hydraulic conveyan-
ce of bulk abrasive materials in the coal and mining indus-
tries and in other industries.
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