Note: Descriptions are shown in the official language in which they were submitted.
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PILOT OPE~ATED COOLANT CONTl~OL VALVES IN MANIFOLD ASSEMBLY
Back~round of the Invention
Technical Field:
This invention relates to rolling mills in general and
more particularly to rolling mills where steel is being reduced
to thin gauge sheets and strips and still more particularly to
coolant applying devices for said rolling mills.
Descri~tion of the Prior Art:
Prior coolant applying devices used on rolling mills have
arranged elongated maniLolds parallel with the work and backup
rolls of the rolling mill and directed Iluids, such as water,
through individual spray nozzles on the manifolds against the
rolls of the mill to provide termperature control and lubrication
during an actual rolling operation.
Several prior art patents relate to pilot operated control
valves including Nos. 3,145,967 to Gardner of 3ept, 1964, No.
3,159,374 to Kroffke of Dec., 1964 and 4,391,296 to Abbott of
June 1983. In each of these patents solenoid operated valves are
disclosed with theoretically control fluid directed therethrough.
In patent 3,145,967 an elastic sleeve is arranged in spaced relation
about a core positioned in a fluid passageway to be controlled.
An annular cavity in the valve around the exterior surface of the
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elastic sleeve enables air pressure to be introduced so as to
distort the plastic sleeve inwardly against the core and thus
close the fluid passageway. The air pressure is controlled by
a solenoid operated valve.
In patent 3,159,374 a flexible diaphragm is positioned to
intercept a fluid passageway through the valve when fluid pressure
is applied to one side of the diaphragm so as to distort the same
into closing relation to the fluid passageway controlled there-
by. The fluid pressure for operating the diaphragm is controlled
by a solenoid alve.
Patent 4,391,296 discloses a valve in which a valve plug
moves into and out of closing relation with respect to a fluid
passageway extending between an inlet port and an outlet port
with the valve plug being urged to closed position in the fluid
passageway by a spring and moved to open position by a solenoid.
A piston is positioned in an extension of the fluid passageway
and a secondary inlet port is in communication with the fluid
passageway below the piston so that manual operation of the valve
can be achieved by introducing hydraulic pressure into the second
inlet port so as to move the piston in the fluid passageway where
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it will engage and open the valve plug.
Applicant's patent 4,568,026 discloses as assembly of
pilot operated coolant control valves in which the individual
valves are arranged in cartridges and in which solenoid actuated
pilot valves must remain energized to afford continuous coolant
flow. The control valves of the present invention are dependent
upon fluid pressure of the coolant supply in the manifold assembly.
These valves must remain open despite any power failure that occurs
and continue spraying the coolant liquid as long as the rolling
mill is operating to protect the rolls against distortion and
such other damage as will occur if the coolant is discontinued.
The prior art pilot operated control valves are unable to main-
tain a fail-safe open condition upon a failure of the solenoid
actuating circuits or faulty operation due to dirt or particles
of foreign materials in the coolant supply. Generally the prior
art coolant valves require complete dismantling of the valve
bodies and the operable parts whereas in the present invention
the valve bodies defining the valve seats and the movable valve
elements take the form of quickly and easily removable cartridges
and due to their novel construction and operating patterns are
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able to operate successfully and remain open while the rolling
mill is operating despite any failure in the pilot valves or
their control medium.
This invention eliminates many of the problems that hereto-
fore existed in connection with pilot operated coolant controlvalves arranged in and supplied by manifold assemblies.
Summarv of the Invention
A pilot operated coolant control valve assembly in a
coolant supply manifold provides a plurality of fail-safe valve
elements in removable cartridge-like assemblies controlling the
supply of coolant, such as water, to individual spray nozzles
directed at steel rolling mill rolls and the like, each of the
multiple coolant control valves is operable to a closed position
by solenoids incorporated therein and operable to open position
by de-energization of the solenoids and the hydraulic actuation
of the coolant control valve elements by the pressure of the
coolant.
Descri~tion of the Drawin~s
Figure 1 is a symbolic illustration of a pair of work
rolls and associated backup rolls of a rolling mill with a
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fluid collecting trough therebelow and several fluid spraying
manifold assemblies therebeside;
Figure 2 is a perspective elevation of a plurality of coolant
control valves in a manifold assembly;
Figure 3 is a cross sectional elevation transversely of one
of the control valves in the manifold assembly of Figure 2 with
parts broken away and parts in cross section;
Figure 4 is a side elevation of one of the coolant valve
assemblies and operating solenoids of Figure 3 with parts broken
away and parts in cross section; and
Figure 5 is a side elevation of one of the coolant valves
of Figure 3 with parts broken away and parts in cross section
and illustrating the wiring for operating the solenoid pilot
valve thereof.
Descrition of the Preferred Embodiment
By referring to Figure 1 of the drawings, it will be seen
that a diagrammatic illustration of a rolling mill discloses
superimposed work rolls 10 and 11 engaged on a pass line 12 and
having backup rolls 13 and 14 as will be understood by those
skilled in the art. Such rolling mills are used in reducing steel
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billets to continuous hot rolled strip and/or sheet. Means for
driving the rolls is not illustrated. A coolant collection trough
15 is shown and four vertically spaced coolant control valve
manifold assemblies 16 are shown positioned in spaced relation
to the work rolls 10 and 11 and the backup rolls 13 and 14. Means
for circulating a coolant fluid such as water from a collecting
trough 15 to the manifold assembly 16 is indicated by broken lines
17.
By referring to Figure 2 of the drawings, a perspective
elevation of one of the coolant control valve manifold assemblies
16 may be seen and it is formed of an elongated housing 18 closed
at its ends 19 and 20 and provided with end extensions 21 and 22
including mounting and adjustment plates 23 and 24 by which the
housing 18 is supported adjacent a roll of a rolling mill as here-
inbefore described in connection with Figure 1 of the drawings.
Inlet ports 25, see Figure 3, comprise means for deliveringa liquid coolant such as water thereinto and a plurality of
body members 26 are sealingly attached to an open side of the
housing 18 and carry nozzle plates 27, each of which carries one
or more spray nozzles 28 through which the coolant is selectively
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directed to the rolls of the rolling mill in desirable volume
and spray patterns.
A vertical section through one of the elongated housings
18 and one of the pilot operated coolant control valve assemblies
secured thereto is seen in Figure 3 of the drawings.
By referring now to Figure 3 of the drawings, it will be
seen that each of the plurality of pilot operated coolant valves
is mounted in apertures 29 in each of the body members 26 and
that each of the coolant control valves comprises a cylindrical
valve body 30 having openings 32 circumferentially spaced therein.
Several annular seals such as ~-rings 33 are carried in annular
grooves in the cylindrical valve body 30 which sealingly engage
apertures in a cartridge body 31 on either side of a cross
sectionally circular cavity 34 therein. A removable member in
the valve body 30 forms a valve seat 35.
By referring to Figure 3 in particular, it will be seen
that each of the cartridge bodies 31 has several openings 36
therein which communicate with the cross sectionally circular
cavity 34 therein and each of the bodies 31 is provided with an
annular flange 37 on one end which registers in an annular cavity
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38 in the body member 26. Annular seals such as 0-rings 39 are
positioned between the annular flanges 37 of the cartridge bodies
31 and the side of the elongated housing 18.
Referring to Figures 3 and 4 of the drawings, it will be
seen that a cylindrical valve element 40 having a closed conical
end 41 is movably positioned in the cylindrical valve body 30 so
as to be movable therein relative to the openings 32 and the area
of reduced diameter of the valve seat 35 therein. It will
also be seen that the inner diameter of the cylindrical valve
body 30 is increased in the area thereof in which the cylindrical
valve element 40 is slidably mounted and that the closed con~cal
end 41 of the valve element 40 will engage the conical valve
seat 35 when the valve element 40 is moved to the left. A spring
42 is positioned within the valve element 40 and engaged against
the inner surface of the closed end 41 thereof and against a
centrally apertured disc 43 which is secured in one end of the
cylindrical valve body 30 by a snap ring 44.
By referring to Figures 3 and 4 of the drawings, it will
be observed that a passageway 45 establishes communication between
the inner end of the cavity 34 in the cartridge body 31 and a
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pilot valve chamber 46 therein. A longitudinally slotted solenoid
plunger 47 is movably disposed in a sleeve 48 which defines a
part of the pilot valve chamber 46 and which sleeve 48 is
positioned within a solenoid coil 49 which is encapsulated by
a suitable resin 40 which holds the solenoid coil 49 in an enlarged
cavity 51 in the cartridge body 31. The sleeve 48 engages a
multiple part closure 52 positioned in one end of the cartridge
body 31. A passageway 53 in the sleeve 48 communicates with a
cavity 54 in the closure 52 and a passageway 55 which communicates
with a passageway 56 extending through the cartridge body 31,
the body member 26 and the nozzle plate 27 to atmosphere.
Still referring to Figures 3 and 4 of the drawings, it will
be seen that the plunger 47 has secondary valve elements comprising
resilient seals in each of its opposite ends, one of which will
engage and close the passageway 53 when the plunger 47 moves to
the right responsive to energization of the solenoid coil 49.
The seal in the opposite end of the plunger 47 engages an opening
in a pilot valve seat 57 when the solenoid coil 49 is de-energized.
The opening in the pilot valve seat 57 communicates by way of a
passageway 58 with the coolant in the housing 18 which is pressurized.
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A spring 59 is positioned between an annular flange 60
on the slotted plunger 47 and an end of the sleeve 48 and urges
the plunger 47 toward the opening in the pilot valve seat 57.
It will be observed that the plunger 47 and the end portion
thereof including the annular flange 60 has a longitudinally
extending slot 61 in the outer surface thereof and that as
illustrated in Figures 3 and 4 of the drawings, the secondary
valve element comprising a resilient seal 62 in the end of the
plunger 47 adjacent the annular flange 60 closes the opening in
the pilot valve seat 57 when the solenoid coil 49 of the device
is de-energized, the secondary valve element comprising the
resilient seal 63 in the opposite end of the plunger 47 being
spaced with respect to the passageway 53. When this occurs,
the fluid pressure of the coolant in the housing 18 of the
manifold communicates with the cross sectionally circular cavity
34 in the cartridge body 31 by way of the several circumferentially
spaced openings 36 and by way of the openings 32 in the cylindri-
cal valve body 30, the fluid pressure engages the outer surface
of the closed conical end 41 of the valve element 40 so as to
move the same away from the valve seat 35 overcoming the resistance
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of the spring 42 in the valve element 40 which opens the main
fluid control valve and permits the coolant in the elongated
housing 18 to flow through the valve seat 35 and outwardly
through the spray nozzles 28 thereby insuring the continuous
delivery of the coolant to the work rolls 10 and 11 and the
backup rolls 13 and 14 which are thereby insured against dis-
tortion or damage which would otherwise occur as a result of
the increased temperatures thereof from the rolling of the hot
steel.
At such time as the rolls 10, 11, 13 and 14 have cooled,
the solenoid coils 49 are energized by electrical circuits, some
of which are illustrated in Figure 5 of the drawings, wherein
conductors 64 and 65 are illustrated extending from the solenoid
coil 49 in the sleeve 48 to separable connections in apertures
66 in the body member 26. Vertical chambers 67 in the body
member 26 provide conduits for the electrical conductors 64 and
65 and in Figure 3 of the drawings, a connecting fitting 68 on
the outer lower surface of the body member 26 comprises the means
of connecting the conductors 64 and 65 with a wiring harness,
not shown, leading to a suitable power source and control switches,
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not shown. When the flow of coolant through the nozzles 28 is
no longer needed, the solenoid coils 49 are energized causing the
longitudinally slotted plunger 47 to move to the right where the
resilient seal 63 in the right end thereof engages and closes the
passageway 53 in the sleeve 48. At the same time, the resilient
seal 62 in the other end of the plunger 47 moves away from the
opening 57 in the pilot valve seat whereupon fluid pressure of
the coolant in the housing 18 extends through the passageway 58,
the opening 57 in the pilot valve seat and into the pilot valve
chamber 46 and through the passageway 45 into the cavity 34 by
way of the apertured disc 43. The fluid pressure thus delivered
into the cavity 43 which is of a greater area than the va].ve seat
35 immediately moves the valve element 40 and its closed conical
end 41 into sealing engagement with the conical valve seat 35
and thus stops the flow of coolant through the device as the
combined fluid pressure of the coolant and the tension of the
spring 42 overcome the pressure of the coolant which has been
maintaining the valve element in open position as hereinbefore
described.
It will thus be seen that the coolant fluid, such as water,
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is readily controlled with respect to shutting off the flow of
coolant to the spray nozzles 28 from whence it is delivered to
the rolls of the rolling mill and it will also be observed that
the arrangement is such that de-energization of the solenoid
coils 49 immediately results in the delivery of the coolant
through the spray nozzles 28 to the rolls of the rolling mill
when this is required and that the opening of the control valves
40 is accomplished by the fluid pressure of the coolant as the
same enters the passageways 36 and the cavities 34 and the open-
ings 32 in the control valve body 30 where it moves the valveelement 40 away from the valve seat 35 and flows outwardly through
the spray nozzles 28. This action is expedited by the establish-
ment of a vent to atmosphere from the chamber 34 around the
control valve body 30 and opposite the closed conical
end 41 of the valve element 40 by way of the apertured disc 43,
the passageway 45, the pilot valve chamber 46, the slot 61 in
the plunger 47 and the passageways 53, 54, 55 and 56 respectively,
which communicates with the atmosphere. The arrangement thus
vents fluid in the interior of the cylindrical valve body 30 and
the interior of the valve element 40 to atmosphere to hasten the
movement of the valve element 40.
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The body members of the device of the invention arepreferably stainless steel and as hereinbefore described it
will be recognized that the actual coolant controlling valves
are formed as readily replaceable poppet cartridges which can be
readily removed and inspected and/or replaced if necessary by
simply removing the nozzle plate 27 which is attached to the body
member 26 by fasteners 70. Tlle cartridge bodies 31 are similarly
attached to the body member 26 by similar fasteners, not shown.
The solenoid coils 49 being sealed and held in place by encapsula-
tion in epoxy resin are protected from damage which might otherwiseoccur from the coolant in which the cartridge bodies are submerged.
The solenoid coils 49 are designed to operate at 24 volts DC and
draw a maximum of .88 amps. The plungers 47 and the solenoid
coils 49 are so designed that the same are fully operational at
85% of the indicated voltage and thus evidence small power require-
ments which substantially improve the invention, both with respect
to automatic and manual input signals for operation.
Those skilled in the art of rolling mill reduction of steel,
both hot and cold rolled, will be familiar with the fact that the
continuous direction of a suitable coolant, such as water, as
128~
specified herein on the work and backup rolls of the rolling
mills controls the temperature of the work rolls and thereby
insures the maintenance of a desirable gauge of the metal being
rolled. A desired coolant temperature easily maintained with the
present system is between 90F. and 160F. with coolant pressure
supplied the plurality of spray nozzles 28 at varying desirable
pressures such as 150 P.S.I. The nozzles 28 are preferably
arranged for indexing at 15 from a transverse center line so as
to insure complete coverage of the work and backup rolls of the
rolling mill on which the device is used. A typical pilot
operated coolant valve assembly for a hot rolling mill as disclosed
herein will operate successfully for several million cycles and
consistently avoid leakage when in closed or non-operating status
and more importantly insure continuous delivery of coolant to the
work and backup rolls as desired.
It will thus be seen that substantially improved pilot
operated coolant control valves in manifold assembly have been
disclosed and although but one embodiment of the present inven-
tion has been illustration and described, it will be apparent
to those skilled in the art that various changes and modifications
may be made therein without departing from the spirit of the
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invention or from the scope of the appended claims, and having
2 thus described my invention what I claim is:
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