Note: Descriptions are shown in the official language in which they were submitted.
3~ ~
The present invention relates to blast furnace equipment,
and more particularly to charging devices.
For example, there is known in the art a blast furnace
charging device which is a combination of a McKee distributor
and two Parry bell-and-hopper arrangements mounted one above
the other and fitted with bell rods. Upon dumping each skip-
load the upper hopper is turned through a preset angle thereby
diminishing to a certain extent but not eliminating completely
the negative influence of distributing the charge in heaps
peculiar to this type of charging apparatus. As a result,
both the chemical and heat energy of reducing gases is under-
utilized. Another disadvantage of this prior art charging
device lies in that it fails to provide reliable control over
radial distribution of charge at a furnace topA
There is also known in the art a charging device compris-
ing a bottom bell with a fixed hopper and a top bell with a
rotary hopper. Mounted above the top bell is a sealing valve-
cover (see e.g., French Patent ~o. 1240287 ) r
The valve of the patent referred to above has a soft
packing between its tapered surface and the top portion of the
rotary hopper, and a labyrinth packing around the bell rod.
When loading a belt-fed charge, the cover is raised~ Upon
feeding a full batch of the charge, the cover is closed and the
charge is lowered into a blast furnace. Said charging device
is characterized by a sophisticated design and fails to provide
~l~
3~
-- 2 --
reliable functioning of the blast furnace at a hi~h top gas
pressure~
Known as well in the art is a charge distributor (see, e.g.
Inventor's Certificate of the USSR ~o. 132652) comprising two
large Parry bells with fixed hoppers. To enable uniform peri-
pheral distribution of the charge at a furnace top arranged
above the upper hopper is a rotary hopper, whose internal sur-
face is fitted with inclined blades, said rGtary hopper being
mounted beneath a movable hopper driven along horizontal guide-
ways so that its outlet can be disposed in a corresponding
place of the rotary hopper7 Such a design enables a requisite
irregular charging to be achieved for various sectors of the ~`
furnace top.
However, this charging device is characterized by extremely
severe operatlng conditions of its equipment, a drive and
support rollers of the bladed rotary hopper in particular,
whereby it is impossible to attain a speed above 18 rpm. Yet,
even at this speed there arise undue efforts as the charge is
accumulated in heaps up to ten tons in weight on one side of
the rotary hopper. As a result, the rollers and races adapted
to carry such heavy heaps of charge fail after one or two
months of operation, with the rotary hopper being incapable
of attaining such angular speed at which the requisite uniform
peripheral distributicn of the charge is ensured.
The Inventor's Certificate of the USSR ~o. 105602 describes
a charging device with a charge distributor, said device
~ 3 ~ ~
compr~sing two bells with ~ixed hoppers and rods~ above which
a receiving hopper is arranged. Mounted inte~mediate o~ ~aid
receiYing hoppex and the top boll is a rotary hopper with two
sloping sur~ace~ and two outlets Upon leaving the receiving
hopper the charge is admitt~d onto the rotary hopper where~rom
it drops through the two outlets to be uniformly spread over
o~ the top bell. Eowev~r, in the course o~ ~unctioning o~ said .
charging d~vlce there ma~ t~ke p~ace a hanging o~ the charg~
in the rotary hopper~ which may be responsible for the blast
fuxnace ba~king.
Moreover, the pro~islon o~ two outlets in the hopper
makes it impos~ible to concentr~te the charge, i~ necessary,
in a particular preset sector at the furnace topO
Another prior-art charging device (see, e g~, Japanes~
Patant No. 7809) comprises two bells with ~i~ed hoppers. Ar-
ranged above the upper hopper are -two plate valve~ with a bun-
~er being located therebelow, the bunker outle~ being narrowed
and it~ walls ~o~msd with guide blade~ The valves aro ~itb~d
with a soft rubber packingO With the valYes being open~ the
plates are drawn out of the ~low of a dropping char~se to be
thereb~ saved ~om wearing which may be caused b~ the moYing
stock. A small b~ll rod is lined with the aid o~ guard rings
and has a packing i~ a gas seal. Eowever~ a consid~rable
height of this dovice has tur~3ed out to be a s~rious problem"
3~7
- 4 -
Therefore, the same firm has proposed another embodiment of a
bell-and-hopper arrangement tsee, Japanese Patent No. 7808),
with a bottom bell having two rods located eccentrically to the
longitudinal axis of the furnace. The disadvantage of the
charging devices with the plate valves resides in that they
require a thorough sizing of the charge to preclude the ingress
of large lumps. The use of unsorted charge leads to a strongly
pronounced peripheral segregation, a feature diminishing
materially the economic effect of the blast furnace process.
The disadvantage inherent in the above outlined charging
devices consists in that they fail to provide for efficient
control of the radial charge distribution at the furnace top.
To enable said efficient control of the radial distribu-
tion of charge at the furnace top, there have been developed
manipulators with movable plates, disclosed in GFR Patents Nos.
1221255, 1250463, 1206454, 1229565, 1230051 and 1231734. As
can be seen from the di,sclosure of the above patents, mounted
round the entire circumference of the furnace top are driven
plates capable of being transferred radially at the furnace
top, thereby varying its diameter. mis affords the possibi~
lity of changing the arrangement of a charge cone top and
radial burden distribution. The disadvantage of said device
lies in its large overall dimensions, which complicates
the construction of the furnace top, and its low reliability
in service. mis equipment operates under severe conditions,
3 1~
-- 5 --
specified by a high temperature, dust-laden atmosphere and
a high gas pressure.
Also known in the art is a charging device comprising
bunkers with upper and low~sr gate valves and adapted for
efficient control of both radial and peripheral charge distri-
bution at a furnace top. Arranged beneath the bunkers is a
driven pan ~see, e.g., GFR Patent ~o. 126614 and Czechoslova-
kian Patent No. 88154). As the charge is bsing poured down,
the pan can bs either rotated or placed in any assigned sector,
this feature providing for the requisite peripheral and radial
distribution of the charge. The disadvantage of said device
resides in its low functional reliability. In the case a
rotary gear fails, the charging of a blast furnace shall cease,
insofar as the fines, contained in the charge, will accumulate
in one sector of the furnace top. As for using unsorted charge,
it does not ensure the requisite regular peripheral dispsnsing
of the charge.
There is likewise known a blast furnace charging device
comprising a large and a small bsll with hoppers and rods.
Mounted above the ~ell is a receiving hoppsr with an appliance
for adjusting its outlet area (see, e.g., I~ventor's Certifi-
cate of the USSR ~o. 374374). In terms of its geometry the -
appliance is shaped as plates fitted with counterwsights and
articulated around the outlet. As the charge passes through
the outlet, its flow is constricted under the action of sai~
.. .
~943~7 .
plates, the charge being therefore concentrated around the
rod. This feature contributes to an averaged peripheral
distribution of the charge. In case offsizes get into, the
plates set off together with their counterweights, increasing
the flow area and ensuring thereby the passage of large lumps.
The disadvantage of said charging device consists in that as
the charge is travelling the plates may jam, being registered
in that position and distorting therefore the preset configu-
ration of the outlet. Moreover, the device fails to provide
charge accumulation in the assigned sector of a furnace top,
it is also not able to adjust radial charge distribution at
the furnace top.
A great number of patents grantecl for various construc-
tions of blast furnace charging devices are indicative of
e~treme importance of the problem, which has been and is
attracting the attention and efforts oE a considerable number
of those skilled in the art and engaged in providing substan-
tial ~ilmprovements in the prior art developments.
It is an object of the present invention to overcome the -
above disadvantages.
The principal object of this invention is to provide a
blast furnace charging device with such an appliance for
adjusting the cross-sectional area and shape of an outlet
annular gap between a receiving hopper and a rod guard ring,
which owing to its geometry would make it possible to simplify
the design of said charging device, extend its service life,
enhance its functional reliability and improve the charge
3~7
distribution at a furnace top by providing both uniform
peripheral distribution and a possibility of charging a
batch to a preset section and decreasing gas and dust
release through the blast furnace charging device.
The above objects are achieved from a broad
aspect of the present invention by the provision of a
charging device for a blast furnace and which is comprised
of a receiving hopper having an outlet therein. At least
one rod is disposed along the longitudinal axis of the
hopper and extends through the outlet. A plurality of -~
coupling rods are disposed above the rod to support the
said rod. A plurality of guard rings are disposad on the
said rod. At least one of the rings has a Eunnel-shaped
outer surface and is disposed at the location of the
outlet of the hopper. Means is provided for adjusting
the cross-sectional area and shape of the outlet and
including a plurality of sector shields. A plurality of
guideways slidably engages the sector shields. The
sector shields are disposed about the tapered guard ring
defining a funnel-shaped an~ular opening therearound and
are adjustable in size. Means is provided for laterally
displacing each of the shields such that lateral displace-
ment of each shield along the guideways changes the size
and shape of the hopper outlet.
Said embodiment of the charging device makes it
possible to improve charge distributing at the furnace
top by both more regular peripheral distribution and by
charging a batch into a preset section of said furnace
top; it allows also simplifying the design of said charg-
ing device, enhancing the functional reliability of its
gears and their longevity and decreasing gas and dust
release through said charging device. ;
, ~
- 7 -
3~
-- 8 --
It is preferable that the appliance for adjusting the
clear passage of the receiving hopper outlet comprise from
2 to 12 sector shields.
The appliance made up of said number of the sector
shields is more convenient in terms of their control and
features a simpler design.
The bottom edges of said sector shields are advisable to
be of such a size as to provide said annular gap around the
rod guard ring, the gap being at least 1.5 times less than
that between the bottom edge of the receiving hopper outlet
and the rod guard rings, but exceeding in size a gap which
may cause the hanging of charge in said receiving hopper.
Such a design would obviate the hanging of the charge in
the receiving hopper, provide for uniform peripheral distri-
bution of the charge at the furnace top and enhan~e the
reliability of operation of a blast furnace.
It should be better that the tapered guard ring be made
as a distributing bell and be linked mechanically with a gear
adapted to transfer it along the rod.
Such an em~odiment of the guard ring would provide
better control of radial charge distributing at the furnace
top without resorting to cumbersome gears to be arranged
inside a blast furnace, it allows also simplifying the
construction o~ the charging device and, which is of prime
importance, cutting down the overall dimensions of the large
bell and its hopper.
,
~l0~L3~7
g
me top part of said distributing bell can mount a
cylindrical guard ring, said ring being located beneath
another guard ring, whose external surface has a configura-
tion of ~a one-sheet hyperboloid of revolution.
This will make it possible to deflect the flow of charge,
bringing it closer to the longitudinal axis of the charging
device and enhancing thereby the uniformity of its peripheral
distribution at the furnace top.
It would be favourable, if the appliance for adjusting
the clear passage of the receiving hopper outlet is equipped
with a sensor capable of travelling along the coupling rod of
the bell rod, being actuated in case the hanging of charge
occurs and delivering a signal to the actuating gear of the
sector shield transfer drive.
It would permit avoiding the overloading of the receiving ;
hopper, raising (drawing apart) duly t:he sector shields with
the aid of their drives and eliminati~g the charge hanging in
the receiving hopper, it would also enhance the reliability
and longevity of operation of the charging device.~;
It ~sus~und practice that the bottom edge of the receiv- ~-
ing hopper be fitted with projections shaped as isosceles
triangles with appropriate lateral sides of said triangles
running parallel to the adjoining parts of the side edges of
the adjacent sector shields.
~ 10 -
Owing to the use o~ said projections the design of the
proposed charging device can be made simpler~ the ovexall
dim~sions o~ the sector shie lds reduced and their tran~fer
drive rating~ cut down.
Each of said sector shields can be made as a fr~me with
strip~ in a wear-resistant material secured thereon.
The strips can be replaced a~ they wear out, or the
strips of appropriate dlmsnsions can be placed with a view to
adausting the annular gap between the rod guard ring~ and the
botto~ edges of the ~actor ~hields, which would allow taking
i~to accolmt both the charge size and its chemical composition.
It i~ preferable that each of said ~qector shield guide-
wag~ have a narrowed part adjoining the runni~g gea~ o~ the
appropriate sector shield.
The provi~ion o~ ~aid guideways would make it possibls ~o
avoid the ~edging o~` th~ ~ector ~hields during theix travel,
enhancing thereby their fu~ctional depe~dabilit~.
It would be ~avourable i~ th~ end portio~ of said guide-
~a~ have hol2sg with a pi~ot being introduced into each of
said holes, said pivot bei~g provided with a detent that i~
registered in a preset position) shaped as a heli~ and capable
o~ interacting with the sector shield running gear.
~ uch a de ign allow~ adausting the extreme positions o~
the ~hield~ and the outlet con~iguration; providing ~or more
regular peripheral distribution o~ the charge at the fu~nace
topO
The present invention will be better understood from a
consideration of a de-tailed description of exemplary embodi-
ments of a blast furnace charging device to be had in
conjJunction with the accompanying drawings, in which:
Fig. 1 shows a blast furnace charging device; a section
by a vertical plane through a longitudinal axis
Fig. 2 - scaled-up section II-II of Fig. 1,
Fig. 3 depicts sector shields, of which one is completely
drawn back and the other one is raised a little
Fig. 4 shows a scaled-up view of an annular gap between
rod guard rings and the bottom edges of the appliance sector
shields,
Fig. 5 illustrates a receiving hopper with an appliance
for adjusting its outlet size, a scale-up section by a
vertical plane,
~ ig. 6 is a conventional scaled-up side view of one of
appliance guideways with a broken out section'
FigO 7 shows a conventional scaled-up view of one of the
guidewa~s (a view along arrow A of Fig. 6); `
Fig. 8 is a top view of a sector shield
Fig~ 9 - section rx-rx of Fig. 8,
Fig. 10 depicts a cnarging device with an appliance for
adjusting the clear passage of a receiving hopper outlet,
with a plurality of bunXers arranged above said receiving
hopper,
Fig. 11 illustrates a charging device with an appliance
for adjusting the clear passage of a hopper mounted above a
large bell,
.
~(~9913~
- 12 -
Fig. 12 is a scaled-up diagramma-tic view of charge
distribution on a small bell and a distributing bell in its
upper (raised) position;
Fig~ 13 shows the same members as those illustrated
in Fig. 12 but with the distributing bell in its lower
(dropped) position'
Fig. 14 shows a large bell with a hopper and burden
distributing pattern upon charging sinter (A) with the
raised distributing bell and coke (K) with the lowered bell;
Fig~ 15 shows burden distributing pattern on the large
bell and hopper upon charging coke (K) with the raised
distributing bell and sinter (A) with the lowered bell.
A charging device comprises a large bell 1 (Fig. 1)
with a hopper 2, suspended from a rod 3, and a top small
bell 4 with a hopper,5, suspended from a hollow rod 6,
whereinto said rod 3 is extended. Mounted above the hopper
2 is a bottom air-lock chamber with a sealing gas lock 7.
The hopper 5 is fitted with a drive 8 adapted for rotating -
it about its longitudinal axis. Above the hopper 5 there
is a receiving hopper 9 with a bottom outlet 10l whereat
3~7
- 13 -
is disposed an appliance for adjusting both the cross-
sectional area (clear passage) and shape of said outlet 10.
Said appliance is rigidly ixed on the e~ternal surface
of the receiving hopper 9 by means of guideways 11, in
which are fixed sector shields 12a and 12b (Figs~ 2 and 3),
forming a hopper-shàped surface. Said sector shields 12a
and 12b are furnished with longitudinal transfer drive 13
(Fig. 1). The guideways 11 are angled to the longitudinal
axis of the hopper 9. The appliance may comprise ~rom two
to twelve sector shields 12. Bottom edges 14 (Figs. 2 and
3) of the sector shields 12 form around the coaxial rods 3
and 6 tFig. 4) an annular opening 15 for the passage of a
charge (with the sector shields 12 brought apart), said
opening 15 being narrowed to the size of an annular gap 15 as
the shields 12 are brought together. ~t the level correspond-
ing to the bottom position of the edges 14 (Fig. 5) of the
sector shields 12 there iq a distributing bell 16, suspended
from the rod 6. Said bell 16 is linked mechanically through
a coupling rod 17 with a drive 18 adapted for shifting the
bell vertically~
.
3~
Guard ring~ 19 in a wear-resistant material are set on the
coupli~ rod 17. At the level of th2 a~nular gap 15 (between
the bottom edges 14 of the sector shields 12 a~d guard rings
19 of the rod 6~ the coupling rod 17 ha~ another guard ri~g 20
whose e~ternal surface is shaped as an one-sheet h~perboloid
o~ ravolution~ with a cylindrical guard ring 21 mounted there~
above. The coupling rod 17 may be provided with one more pair
o~ the guard rings 20 and 21 spaced ~rom the first pair at a
distance equal to the strok~ o~ the bell 16.
~ he edges 14 o~ the sector shields 12, lateral side~ of
the guard ri~gs 20 and 21 a~ well a~ the distributi~g bell 16
can be alflo either coated with a wear-resistant material, such
a~ sormite, or made o~ a wear-r~ssistant material, e.g., relite.
~he rod~ 3 and 6 are suspended .~rom appropriate coupling rods
22~ whareon char~e hanging sansors 23 and rod 24 are arranged,
with the rod 24 overhanging into the sp~ce of the receivi~g
hopper 9. The rod 24 i~ capable o~ travelli~g along the coupl-
ing rod 22~ The sensor 23 i~ electricall~ associated with a
co~tact 25 ~ixed on the coupling ro~ ~2, th~ contact 25 bsing
in turn associated alectrically with a centrol panel 26 (~ig.
1) of the chargin~5 devic~ and with the driveq 13 o~ the sector .
shie ld~ 12 .
Arranged under the bottom bell 1 is a blast-furnace top
27~ wherein the charge level i~ identified by item 28. ~he lo-
wer edge o~ the outlet 10 (~?ig~ 5) o~ the rec~iving hopp~r 9
3~
can be either shaped as a circumference or fitted with pro-
jections 29 i~ the ~orm o~ isosceles triangles, with appropria-
te lateral sides of said triangles running parallel to the
adjoining parts on the lateral side~ of the a~jacent sector
shield~ 12 (~ig. 2).
The guideways 11 (Fig~ 6) are provided with top detents
and bottom detents 31 that are fixed thereon to limit the
stroke of the sector shields 12 (Fig. 7). ~he top detents 3Q
(Fig~ 6) are located so that the bottom edges 14 (~ig~ 2) o~
the sector shields 12 in their e~treme top position are
arranged level with or above the bottom edge bounding the out-
let 10 (~i~. 5) of the receivin~ hopper 9, The bottom detents
31 (Fig. 6) are disposed so thab ~he sec~or shields 12 (Fig.
2) in their e~treme bottom (low,sred) positio~ are brought to-
gethar, with their bottom edge~ 14 forming the annular gap 15
around the guard ring 21 (Fig~ 5). The bottom edges 14 of the
sector shield~ 12 can be arcuated. If that is the case, on
being drawn together theg can form either a ¢ircumference ~h)
~ig. 4) or a line (g~, ~or which the de~lection o~ its poi~ts
~rom the radiu~ of said circumference towards the la~ger valu~s
is the ~reater~ the mor~ the curve ~i) o~ the circle cha~ge
distributing diagram deviates~ i~ case o~ a round openi~g (~ap),
~rom its mean value towards the lower ones. And vice versa,
the more the distanc~ from the edges 14 (~ig. 5) of the open~
i~g (gap) 15 deflects ~rom the value of the radius towards the
33a~
lower valuss~ the gr~ater the te~de~cy of the distributio~
curve towards the larger value~.
The guideway~ 11 are made as beams 32 (Figs~; 6 and 7)~
with plates 34 being secured to their top and bottom le~gth-
wiss ~id~s 33 at right angles to their longitudinal axi~.
Fa~tened to the end~ o~ the plates 34 parallel to the aY~i~ o~
the b~am 32 are bars 35 accommodating running gears 3~ 3 re~
Ierred to hereinafter as runners ~6 ~ig~ 7), of the sector
schields '12, with the c;ylindrical surîace of said runrler~ 36
~ound in co~tact with the narrowed sides 37 of the bars 35.
~he width o~ said narrowed sida 37 ~hall be ~ized proceed-
ing ~xom the most favourable condition~ for dropping pulveri-
zed charge and precluding the Jamming of said runners 36;
thu~, it should bs ~ufficiently large to prevent the warping
of` said naxro~ed side 37 in the course of operationO
A~ i~ known, tho end part~ of the beam 32 (Fig. 63 ar~
~itted with the detent~ 30 ~nd 31~ each o~ said detents 30 and
31 comprising a head 38 (Fig9 7)9 made as a halix fitted ri-
gidly on a pi~ot 39 that i~ i~troduced into one of appropriata
hole~ 40 ~ig. 6), provided along the beam 32 a~ spaced apart
at a di~tance equal to the stro~e o~ a rim o~ the head 38
(Fl~s. 7) ~i.e. to the difference between the ma:~imum and mi~
nimum distances ~rom the rim of said head 38 to lt~ pivot 39)~.
~he head 38 mo~mted on the beam 32 is provided with a locator
41 ~dapted to register said head 38 in a preset po~ition.
: :
~0~143~7
- 17 -
The sector shield 12 has a frame (a framework) 42
(Figs. 8 and 9) made in the form of a truncated cone sector
and provided with blades 43 on which the runners 36 are fi~ed.
Fastened to the frame 42 are detachable shaped grate bars 44
made as strips of a wear-resistant material. The bars 44 are
the segments of a truncated cone projecting downwardsO
The bottom endface edge of each grate bar 44 projects
with its curvature 45 (Fig. 9) downwards, its middle part
having from below a rib 46, with the grate bars 44 striking
with said ribs 46 against the bottom endface collar 47 of the
frame 42. The grate bar 44 is securecl to a top endface collar
48 by way of a locator 49. The grate bars are abutting
tightly against each other forming ac~continuous surface all
over the area of the sector shield 12 (Fig. 8). Use can be
also made of a solid sector shield 12, e.g. made as an
integral casting which has no runners but is sliding instead
along the bars 35 (Fig. 7).
The device of the invention may also prove to be most
advantageous in the case when a plurality of bunkers 50 with
gas-sealing valves 51 are arranged above the receiving hopper
9 (Fig. 10).
The appliance for adjusting the clear passage of the
xeceiving hopper 9 (Fig. 11~ is also adaptable when said
receiving hopper is located on a blast furnace above the
large bell 1, with the other hoppers being disposed above
said receiving hopper 9. According to this invention, the
3~'7
- 18 -
appliance provides for a preset charging of burden consti-
tuents~ sinter and coke, onto the bell 1 (Figs. 14 and 15)
and in the hopper 2, this being effected with the help of the
movable distributing bell 16 (Figs. 12 and 13).
With a blast furnace operating at a steady duty use can
be made of a stationary bell 16 (Fig. 1), fixed on the guard
rings 19.
It should be bornerin mind that the present invention is
in no way limited to the exemplary embodiment disclosed here-
with, and various modi~ications can be resorted to by those
skilled in the art as to the layout of various particular
units of the charging device, such as fall within the true
spirit and scope of the present invention defined in the claims
which followcl
The herein-proposed charging device operates in the
following manner.
A charge batch (equal in volume to a skipload) is loaded
into the blast furnace receiving hopper 9 (Fig. 1). In this
case the sector shields 12 are set to their extreme bottom
(lowered) position. Upon filling to capacity the space of the
receiving hopper 9 the charge is gradually poured through the
annular gap 15. Each next batch is charged in a similar manner.
As soon as a preset volume of the stock (a complete charge) is
accumulated in the hopper 5 on the bell 4, the dumping action
~I,.05'1L~31
-- 19 --
of the small bell 4 is initiated, the charge being poured
into the lower hopper 2 on the bell 1. Another charging
schedule is also possible: each batch of the charge (a
skipload) or two such batches together being lowered on the
bell 1. ~s the large bell 1 lowers, the charge runs out of
the hopper 2 into the top 27 to fill it to the level 2~. :
As the charge passes through the calibrated narrow
annular gap 15, it is regularly distributed round the
circumference of the furnace top 27 according to its mass,
size and composition (cokel sinter). mis feature provi~es
for highly uniform peripheral distribution of the charge at
the top 27~ The provision of the guard rings 20 and 21,
decreasing in diameter at the level of the outlet annular `
gap 15, contributes to said uniform dispensing action. The
external surface of the guard ring 20 similar in configuration
to a one-sheet hyperboloid of revolut.ion is conducive to
smooth running of the charge through said annular gap 15, .
whereas the use of the guard ring 21 made as a cylindrical ~.
insert of a minimum diameter precludes the jamming of charge
lumps in said annular gap 15. :~
Insofar as at the level of the bottom edge 14 of the
sector shields 12 the diameters of the guard rings 20 and 21
decrease as compared with those of the other guard rings 19,
it affords the possibility of reducing accordingly the out-
side diameter of the annular gap 15, the flow of charge being
thereby deflected to the center of the receiving hopper,
whieh in turn contributes to a more uniform peripheral dis-
tributing of the charge at the furnace top 27. To provide
for a still greater degree of uniformity in peripheral
3 ~L~
- 20 -
dispensing of the charge at said furnace top 27 as the charge
is being dropped through the annular gap 15, the hopper 5 is
capable of being rotated by the drive 8.
The hopper shall turn through a preset angle after a
charge batch has been completely poured, but in view of a
high degree of uniformity in peripheral distribution of the
charge ensured by the proposed charging device, the hopper
5 can remain immovable. Hence the hopper 5 can be made fixed
without~the drive 8 and a gland seal. In the meantime its
capacity can be increased to accommodate a whole round o~
charges (a batch equal in volume to several skiploads).
In case a stable scaffold is formed in the receiving
hopper 9, w~lich takes place quite occasionally, the charge
will not run off through the annular gap 15. If that is the
case, the rod 24 will strike against the charge surface
within the receiving hopper 9, as the bell 4 is lowered, and
wiLl not descend together with the coupling rod 22, the
contact 25 being thereby broken and delivering a signal to
the control panel 28 to raise the sector shields 12 by means
o~ their drives 13~
Upon raising the sector shields 12, the annular gap 15
will increase, the scaffold will break down and the charge
will drop into the hopper 5~ After that a signal is sent
from the control panel 26 through a time relay to lower the
sector shields 12 (Fig. 2), the latter will draw together,
returning to their initial position.
. . . . .. .
- 21 -
As the sector shields 12 are being transferred, the
runners 36 (Fig. 7) are rolling along the narrowed sides 37
of the bars 35. In spite of extremely dust-laden atmosphere
in the place o~ location of the guideways 11, the dust is
not deposited on the narro~ed sides 37 of the bars 35. The
dust, if accumulated thereon, will be removed from said
narrowed sides 37, a feat~lre precluding the wedging of the
sector shields 12. Said efficient removal of the dust is
ensured because of a small width of the narrowed sides 37,
with the runner 36 exerting such a pressure during its travel
that the accumulated dust is removed with the material of the
narrowed sides 37 being not distorted~ The removed dust
passes between the plates 34 or gets on their sharp top edges,
wherefrom it is free to fall off outside the limits of the
guideways 11.
If a greater amount of sinter or coke (Figs. 14 and 15),
contained in the furnace burden must ~e fed into a particular
sector of the furnace top 27 (Fig. 1) ~said sector being ~;
located against the sector shield 12a (Fig. 3)), as compaxed
with that supplied into its other sectors, one or a plurality
of the sector shields 12 (Fig. 3) located above said sector
are raised, with the clear passage of the outlet being
thereby increased at this section. A greater flow of charge
will therefore pass through this sector of the outlet, with
the amount of the charge at this particular section of the
furnace top 27 (Fig. 1) increasing accordingly. This will
be accompanied by accumulation of fines in this place, i.e.
peripheral charge segregation at the top 27 will be attained.
3~7
- 22 -
It is preferable that at least two sector shields 12 be
used, insofar as one shieLd is not able to close the clear
passage of the outlet of the hopper 9. More than twelve
sector shields 12 are inexpedient, as their control becomes
too complicated and their functional reliability diminishes.
In the meantime the required charge accumulation can be
provid0d during its supply at any point round the circum~
ference of the furnace top 27. To this end two adjacent
sector shields 12 (Fig. 3) are raised to a different height~
e.g. a shield (a) is raised completely and a shield ~b) only
partly.
Radial charge segregation at the furnace top 27 (Fig.
1) is controLled with the help of the distributing bell 16
(Figs. 12 and 13). In order to feed fines to the periphery
and coarse ~ractions to the center, the bell 16 (Fig. 12) is
raised to a mark ~e). Then the flow of charge will be
deflected to the walls of the hopper 6, the charge running
at the angle of repose to the center, this resulting in
accumulating the fines at the walls of the hopper 5 and the
coarser fractions in its central part. As the charge is
lowered from the hopper 2 (Figs. 14 and 15) into the furnace,
its radial distribution pattern at the furnace top 27 (Fig,
1) is essentially not changed.
3~L~
To enable still better preservation of the radial
charge distribution pattern at the furnace top 27 optimized
angles oE inclination of the generatrices of the bell 1 and
hopper 2 are se-le-cted.
For charging the coarse fractions to the periphery and
the fines to the center, the distributing bell 16 (Fig. 13)
is lowered to a level (f). In that case the charge will be
first~y poured to the center, where an accumulation of the
Eines will be formed, whereafter it will slip at the angle
of repose to the walls of the hopper 5, where the coarse
fractions will be found.
To enable local peripheral accumulation of the sinter
at the furnace top 27 (Fig. 11), the sinter is poured into ~ -
the hopper 2 with the distributing beLl 16 raised to the
Level (e), the coke being dropped with the bell 16 lowered
to the level (f)~ In this case the best results in terms
of radial sinter and coke distribution are attained by
lowerin~ a sinter batch (a skipload) Eollowed by a coke
batch, whereupon the cycle is repeated by descending again
firstly the sinter batch and then the coke batch, each
batch being lowered separately on the bell 1 (Fig. 14).
Where a need arises to supply the sinter (A) (Fig. 15) to
the center and the coke (K) to the periphery, a reversed
loading sequence is followed in supplying the charge onto
the large bell 1
~43~7
- 2~ -
For charging coarse sinter fractions to the center and
coarse coke fractions to the periphery of the furnace top 27
(Fig~ 1), batehwise charging (by loading separate charges)
is resorted to, i.e. at first onLy the sinter is charged on
the large bell 1 with the bell 16 raised to the level (e),
whereafter, upon dropping the sinter on the furnace top 27,
only the coke is charged onto the large bell 1 with the bell
16 being lowered to the level (f).
For char~ing one or another fraction in the middle of
the radius or into some other part of the furnace top 27
(Fig. 1) the bell 16 is set to an intermediate position
between the levels (e) and (f) or some other sequence of
operations is employed in supplying the charge constituents
into the bell. To ensure more uniform peripheral distribu-
tion of the charge at the furnace top 27 the bell 16 can be
rotated or its surface can be bladed.
Both the size and configuration of the annular gap 15
can be varied without stopping the charging of a blast fur-
nace. To this end the locators 49 tFig. 9) are carried off
and the grate bars 44 are drawn out to be replaced by new
ones with the ribs 46 of a re~uisite configuration.
With the receiving hopper 9 (Fig. 11) arranged above
the bottom (large) bell 1, the charge constituents are
blended to a lesser degree as the charge descends to the
level 28 in the blast furnace, but it complicates the control
over-the functioning of the charging mechanisms. In this
case the top bell can be replaced by the bunkers 50 (Fig.
10) with the gas-sealing valves 51. -
43~L7
- 25 -
~ he herein-proposed charging device has a broad control
and radial charge distributing range at the furnace top 27
until the dumping action of the large bell 1 is initiated and
the charge drops into the blast furnace to the level 28.
Large-capacity blast furnaces of today employ large bells
up to 8 m in diameter, which appreciably complicates the
manufacture, handling and erection of su~h bells. According
to this invention, a possi~lity is provided to reduce the
diameter of the large bell 1.
Owing to more regular radial and peripheral distribution
of the charge at the top 27 and a possibility of selecting
and supplying the whole round of charges onto the top bell, a
more stable gas flow is provided in the furnace, thermal - ``
distortion of the charging equipment and, hence, gas release
to the atmosphere and abrasive wear of contact surfaces are
decreased~ This contributes to a lon~er service life of the
charging devices.
The charging device of the invention is noted for a simple
and reliable construction, providing for the most favorable
radial and peripheral distributing of the sto~k at the fur-
nace top; it enhances also the durability of the bell-and-
hopper arrangements and makes it possible to cut do~n the
~ameter of a large bell.
Moreover, the reliability of operation of the charging
device is enhanced, as it does not comprise rapidly rotating
charge-dispensing gears; charge grinding is decreased.
