Note: Descriptions are shown in the official language in which they were submitted.
BACKGROUND OF TH~ INVENTION
Field of the Invention
The present disclosure is directed to a sliding gat~ valve having
particular application for use as a furnace valve in which th~ pouring orifice
is substantially horizontal. The invention is directed to a remanufacturable
sliding gate member.
Summary of the Prior Art
The prior art is exemplified by Shapland U.S. Patent 4,063,668 issued
December 1977 and also U.S. Patents of Metacon AG numbered 4,269,399 and
4,273,315.
As to the Shapland Patent 4,063,668 it should be noted that it
utilizes bilaterally symmetrical slide gates and top plates. While the use on
a bottom pour vessel such as a ladle, where there is substantial clearance,
has been highly satisfactory; when employed on the side of a furnace where
extensive auxiliary equipment appears, space limitations can cause a problem.
The Metacon Patents 4,269,399 and 4,273,315 both utilize a slide gate
which shuts off in the down position. This has the distinct disadvantage when
erosion occurs near the bore of the slide gate or the stationary plate, of
providing a pocket for slag or metal to solidify and further, upon
reactivation, cause additional erosion.
Furthermore, with the valves which close in the down position, upon
opening the metal cascades from an upper position to a lower position on the
pour nozzle causing a free~fall area which initially creates a turbulance and
additional erosion potentiaL adjacent the portion of the nozzle which slides
against the stationary plate. This condition can be aggravated when
throttling.
Accordingly it becomes desirable to develop a furnace valve which
minimizes space, minimizes the potential of a poc~et where slag or metal can
collect in the off position, and to provide for activating the pouring with a
direct connection between the furnace opening and stationary plate and the
bottom portion of the pouring nozzle which communicates with either a trough
or directly to a ladle.
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The present disclosure is ~irected to a sliding gate valve emploged
on the side of a furnace as a furnace valve, in which the mechanism is so
structured that the shut off occurs by directing the slide gate to the up
position rather than the down position. In addition, to facilitate a
redl~ction in space at the slide gate, the slide gate is desirably configured
to be asymmetrical, with the short end extending upwardly erom the pour
opening in the nozzle. A refractory lined heat shield protects the sliding
gate carrier and also serves to mount a collector extension when used More
specifically, the slide gate is provided with a metallic frame which retains a
monolithic cefractory into which erosion resistant refractory inserts or
preformed members are csst. Means are desirabl~ provided to remove the spent
refractory for remanufacture thereby reclaiming the casting. Similarly in the
top plate, means are provided for remanufacture and for facilitating proper
orientation of erosion-rssistant refractory inserts such as zirconium oxide in
the manufacture of the stationary plate. The top plate is symmetrical to
provide full travel pressure face relationship with the sliding gate. Both
the stationary plate and slide gate casting have spring pad back up
reinforcements. The top plate desirably has means for securing a well nozzle
to it.
A method of operating a furnace valve and its structure are described
in which shut-off occurs with the sliding member in the up position. Also
described is such a valve in which the initial flow of metal is directly on to
the surface of the pour nozzle thereby eliminating initiating the pour with a
cascading of molten metal onto the refractory bore of the sliding gate.
A furnace valve is described with an asymmetric&l sliding gate in
whi~h space limitations are reduced, and in which this particularly occurs at
the low end of the valve.
A furnace valve with a stationary plate and a sliding gate are
described which can be remanufactured without destroyin~ the machined housings
for the respective stationary plate and sliding gate. Further described is
provision~for mounting the well nozzle to the top plate befo~ insertion into
the tap hole bloc~.
- ~ More particularly, in accordance with the invention, there is
provided for use in a valve for controlling flow of high temperature liquid
material, a sliding gate having a pouring orifice, comprising in combination,
PAT 12a93-1
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- a frame for containing refractory,
- said frame being asymmetrical about its transverse axis and
symmetrical about its longitudinal axis,
- a long portion and short portion of the frame,
- said pouring orifice being in the short portion of the frame~
- a spider-like support in the long portion of said frame,
- a circular reinforcing support at an offset portion from said
spider and in the short portion of the frame to support the pouring orifice of
said slide gate,
_ a refractory plate for insertion in said frame opposite said
spider,
- a refractory insert having a collar and depending nozzle portion
for insertion in the nozzle opening reinforcement of said frame,
- jig means adjustably extending from the frame in surrounding
relationship to said spider for supporting the refractory plate opposite the
same,
- a monolithic castable refractory imbedding the refractory
inserts in the frame,
- and a through opening in the spider in an open communication
with the monolithic refractory,
whereby a spent such valve can be remanufactured by pressing a mandrel against
the nozzle portion and a cylindrical knock-out plug in the through opening.
Embodiments of the invention ~ill now be described with reference to
the accompanying drawings wherein,
FIG. 1 is a transverse sectional view of a furnace with a installed
valve;
FIG. la is an enlarged sectional view taken from location la on FIG.
1 snd showing the relationship between the end of the collector and the pour
tube;
FIGS. 2L and 2R are a composite exploded view of the subject valve
s~ith 2L representing the left-hand portion of the illustration and 2R
representing the right-hand portion of the illustration;
FIG. 3 is an elevational view of the sliding gate assembly upstream
face;
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FIG. 4 is a transverse sectional view of the sliding gate assembly
taken alon~ section line ~~4 of FIG. 3 and in the same scale as FIG. 3;
FIG. 5 is a perspective view of the slide gate collector insert;
FIG. 6 is an elevational view of the casting for the slide gat~
showing the upstream face;
FIG. 7 is a transverse sectional view of the slide gate casting taken
along section line 7-7 of FIG. 6;
FIG. 8 is an elevational view of the slide gate casting showing the
downstream face;
FIG. 9 is a perspective view of the collector tube;
FIG. 10 is an elevational view of the slide gate refractory insert;
FIG. 11 is a side view of the slide gate refractory insert shown in
FIG. 10;
FIG. 12 is an upstream face view of the stationary plate assembly;
FIG. 13 is a transverse sectional view of the stationary plate taken
along section line 13-13 of FIG. 12;
FIG. 14 is an upstream face view of the stationary plate frame only;
FIG. 15 is a transverse sectional view of the stationary plate frame
taken along section line 15-15 of FIG. lq;
FIG. 16 is a downstream face view of the stationary plate frame only;
FIG. 17 is a perspective view of the stationary plate insert drawn to
an enlarged scale;
FIG. 18 is a perspective sectional view of the well nozzle drawn to a
larger scale;
FIG. 19 is a downstream face view of the heat shield assembly;
FIG. 20 is a transverse sectional view of the built-up heat shield
taken along section line 20-20 of FIG. 19; and
FIG. 21 is 8 detail section of the valve orifice similar to FIG. 1
drawn to a larger scale showing an alternative construction well nozzle.
Valve Assembly
As shown in FIG. 1, the furnace valve 10 is secured by means of an
adapter 11 to a furnace 12. The furnace 12 is typically used for the
preparation of steel which is to be tapped into a ladle, and transferred
elsewhere in the steel mill for further processing.
Interiorly of the furnace 12 a refractory lining lb is provided. At
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a side wall portion of the furnace 12, provision is made for a well 15 for
tapping the steel from the furnace after it has been smelted and otherwise
processed. The well 15 includes an inner octagonal or hexagonal tap hole
block 16, and an outer octagonal or hexagonal tap hole block 18. Both the
inner tap hole block 16 and outer tap hole block 18 are shown here as having a
hexagonal cross-section, but other locking type exterior faces may be used.
A tap hole well nozzle 19 is in open communication with the inner tap
hole block 16 and outer tap hole block 18 and couples directly to a stationary
plate 20. The stationary plate 20 is in pressure opposed relationship to a
slide gate 21 which, in turn, is held by a slide gate carrier 22 to
reciprocate ir, sliding relationship with the stationary plate 20.
A carrier connector 24 is provided on the slide gate carrier 22, and
is coupled to a carrier drive 25 for reciprocating the slide gate carrier 22
and the slide gate 21. To be noted is a carrier heat shield 26 secured to
shield mount 28, the carrier heat shield 26 being in surrounding relationship
with the collector 29 of the slide gate 21.
The slide gate collector 29 is optionally coupled to an extension 30
by means of the interposed heat shield 26 for extending the pour path of the
molten metal being tapped from the furnace 12 secured by means of shield bolts
33. Interiorly of the slide gate carrier 22 are a plurality of carrier spring
pads 35 which directly en~age the underneath portion of the slide gate 21 and
provide a pressure face-to-face relationship between the slide ~ate 21 and the
stationary plate 20. The carrier bottom 31 and carrier top 32 contain the
spring pads 35. The foregoing elements are secured within a frame assembly
36, which includes the frame bottom 38 and the mountin~ plate 40. The
mountin~ plate 40, in turn, is secured to the adapter.
Turning now to FIGS. 2L and 2R, the furnace valve will be described
in greater detail, and the detailed parts shown in their disassembled but
related relationship to the various components of the furnace valve 10.
Proceeding ~enerally from left to right, it will be seen that the inner tap
hole block 16 and outer tap hole block 18 are positioned to provide for fluid
flow to the well nozzle 19. The mounting plate 40, as mentioned earlier, is
secured to the adapter 11.
As noted in FIG. 1, a monolithic section 17 is cast into the
counterbore on the back of the mounting plate 40. Anchors 41 are employed to
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secure the same in place. The mounting plate monolith 17 thus provides for a
positive refractory-to-refractory butt joint with the end of the outer tap
hole block 18. The tapers 110, 111 are secured with mortar pressed in place
when the mounting plate 40 is secured to t~e adapter 11. Thus a full
refractory-to-refractory joint is present to inhibit penetration of the joint
between the three elements, the outer tap hole block 18, the replacement
nozzle 19, and the mountin~ plate 40. Furthermore the mounting plate 40 forms
a zero clearance seal to the adapter plate refractory. The frame assembly 36
is provided with a pair of lifting eyes ~l~l which permit the entire valve to beremoved from the adapter 11 and replaced as a pre-assembled unit. Upon any
such removal, the face of the mounting plate monolith 17 can be inspected, and
patched or otherwise maintained. Alternatively, a hinge assembly ~l5 (see FIG.
2R) and latch assembly 50 (see FIG. 2L) are provided for those installations
where the refractory is to be replaced and the valve serviced without removing
the same from the furnace. The hinge assembly 45 is secured to the frame 36,
and provided with a hinKe activator sleeve 46 into which a hinge rod may be
inserted. The hinge retainer 48 is on the frame 36, and the hinge assembly is
secured by means of hinge pin 49.
The latch assembly 50, shown primarily in FIG. 2L, is secured by
means of the latch hinge pin 51 to the frame 36 and then inactivated by means
of latch lock assembly 52. Latch pivot pin 54 and its associated latch stub
pin 55 complete the assembly of the latch. As described earlier, when the
hinge assembly 45 and latch assembly 50 are in place, the carrier bottom 31
and the carrier top 32 retain the carrier spring pads 35 to engage the sliding
gate 21. The stationary plate 20 is sandwiched between the sliding gate 21
and the inner portion of the mounting plate 40 and the well block nozzle 19
nest within the center of the stationary plate 20 as will be explained in
greater detail where those parts are described separately.
Slide Gate Assembly
The slide gate assembly is shown in FIGS. 3-11. There it will be
seen that a slide gate frame casting 60 having an outer skirt 61 and a
collector pad ring 62 receive and mount the slide gate collector 29. As shown
in FIG. 8, an insert pad ring 64 is provided in the slide gate frame casting
60 and centrally thereof provision is made for a knockout hole 65. A casting
spacer mount 66 is machined into the insert pad ring 64 to facilitate
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orientation during casting of the monolithic material which embeds the slide
gate collector 29 and the insert 70. Inner ribs 68 and outer ribs 69 are
provided interiorly of and adjacent to the insert pad ring 64 to giva
additional strength.
As shown in FIGS. 3 and 10, the insert 70 has a collector crotch 71
which engages the collector rim 72. The collector rim flat 74 and the insert
70 are coplanar and formed of an erosion and/or abrasion resistant material
such as zirconium oxide or aluminum oxide since they are the elements which
are in contact with molten metal. The collector tube 75 (see FIG. 9) is
provided with threads 76 for threadedly engaging the slide gate frame casting
60. The detents or crimps 78 at the end of the collector tube 75 opposite the
thread 76 locXingly engage the monolithic material 80 as best shown in FIG.
4. A portion of the monolithic material 80 extends forming a refractory
collector end 84. That portion of the short end 85 of the sliding gate 21
presents a face of monolithic material which does not come in contact with the
molten metal. Also to be noted are the side flats 81 and end flats 82 of the
slide gate frame casting 60. Optionally lifting holes 86 are bored in the
side flats 81.
Stationary Plate
The stationary plate is shown in FIGS. 12-17 inclusive. The
stationary plate 20 is symmetrical, even though the sliding gate 21 is
asymmetrical. As will be appreciated from the reinforcing construction of the
stationary plate 90, it is provided to give full support to the pressure from
the carrier spring pads 35 in all positions of travel of the slide gate 21 and
the slide gate carrier 22. The stationary plate frame 90 is provided with a
skirt 91. Centrally the stationary plate orifice insert 92 with its insert
lock groove 94 is positioned for interlocking casting within the frame 90.
Xnockout ~oles 95 are provided at opposed positions in the frame 90, and each
has a monolithic lock ring 96.
A well block nozzle stepped seat 98 is provided centrally of the
stationary plate 90, and terminates in one face of the stationary plate
orifice insert 92. Threaded bores 99 are provided in the reinforcing rings 97
which surround the knockout holes 95. The bores 99 are threaded to receive
funnels useful in casting the monolithic refractory 93 into the stationary
plate 20.
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As shown particularly in FIGS. 13 and 1~, a preferred construction of
well nozzle 19 is provided which rests atop the well nozzle seat 98 within the
stationary plate frame 90. A locking assembly 105 is provided to secure the
well nozzle 19 to the stationary plate 20. More specifically a clamp washer
106 is secured by means of mount threads 107 in the stationary plate 90
through the medium of the washer mount screw 108. The washer 106 then is
secured into the crescent-shaped washer lock 109 in the refractory of the well
nozzle 19. Once this locking has taXen place, the taper 110 on the block
nozzle 19 is secured in mating engagement with a mating taper 111 (see FIG. 1)
in the outer tap hole block 18 secured within the refractory 14 of the furnace
12. The alte~native construction of the well nozzle 19 is shown in FIG. 21,
where the refractory 104 is en~ased within a well nozzle frame 100, and
includes a well nozzle rin8 101 which is lockingly engaged with the mountin~
plate, and secured in position by means of the well nozzle mortar 102, again
as shown in FIG. 21. As shown in FIG. 1, the top plate is secured in place by
top plate retaining pins 42.
The Heat Shield and Nozzle Extension
The heat shield 26 is shown in FIGS. 19 and 20. There it will be
seen that an extension mount 112 extends from the heat shield, and includes
mounting pin slots 114 to receive the nozzle extension 30 and secure the same
to the heat shield, and more particularly against the monolithic refractory
115 which is cast into the heat shield, and held in place by the combined
action of the V-locks 116 and the rim 118 surrounding the heat shield base
plate 119. A unique advanta~e achieved by the refractory lined heat shield 26
becomes more apparent from the structure as shown in FIG. la. The nozzle
extension 30 has its refractory linin~ held in place by means of the nozzle
extension frame 120, normally formed from a rolled sheet of metal. The frame
120 is welded to a semi-circular nozzle extension frame mounting flange 121 at
the joint 122. When the nozzle extension 30 is secured to the heat shield 26
as described above, provision is made for mortar 125 to seal the end of the
monolithic refractory material 80 of the collector to the nozzle extension 30
in a refractory to refractory relationship. By utilizing this construction,
there is no metal to metal relationship in the path of any leakage of molten
metal should it erode the mortar 125 bonding the collector monolith 80 to the
nozzle extension 30. Experience has shown that where there is a metal to
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metal bond, and any leakage or erosion occurs, it will accelerate rapidly;
whereas if the bond is refractory to refractory, or even refractory to metal,
this tendency of the molten metal to leak or burn its own path is minimi~ed.
Thus the relationship between the heat shield 26 and the nozzle extension 30
has been enhanced by this construction to permit flexibility of mounting, and
in addition, security against break out.
Remanufacture
As the stationary plates 20 and slide gates 21 are worn, they may be
remanufactured and their respective frames reclaimed. As shown in FIG. 4
primarily, a mandrel or press can engage the monolithic collector end 84,
while at the same time a mandrel is inserted in the knockout hole ~5. The
combined pressure removes the collector insert 29 and the face insert 70.
Thereafter by tapping or shaking, the balance of the monolithic cast material
80 may be removed.
Similarly, when the stationary plate 21 is to be remanufactured,
mandrels are provided to press on the knockout holes 95 at the same time a
central mandrel engages the stationary plate orifice insert 92.
The casting spacer mount 66 of the sliding gate 21 as shown in FIGS.
6 and 7 permits the insertion of a spacer to support the insert 70. The four
concentric spacer bores 99 in the top plate frame 90 are connected with a
pouring spout and serve as sprews for the castable material. Lifting holes 87
may be optionally provided in the stationary plate in the same fashion as in
the sliding gate.
Summary
As pointed out above, the furnace valve 10 as shown is modified by
means of an adapter 11 to accommodate a furnace 12 in which the side tap is at
an angle to the vertical. Lifting eyes 44 are provided on the frame assembly
36 so that the entire valve 10 can be removed. In cases where the valves 10
are to be always removed in their entirety, the hinge assembly 45 and the
latch assembly 50 may be modified and simplified to a simple clamp. In the
valve 10 as shown, however, the hinge assembly 45 and latch assembly 50 are
shown to illustrate that the valve can be used in either mode when the
refractory is replaced while the valve 10 is on the furnace 12, or in the
event it is removed.
PAT 12693-1
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Although particular embodiments of the invention have been shown and
described in full here~ there is no intention to thereby limit the invention
to the details of such embodiments. On the cont~ary, the intention is to
cover all modifications, alternatives, embodiments, usages and equivalents as
fall within the spirit and scope of the present invention, specification, and
appended claims.
PAT 12693-1
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