CA1104814A - Apparatus for applying refractory material onto the inner surface of a furnace - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE:

In an apparatus of this invention which applies refractory material in either wet or dry form onto the inner surface of a furnace, the improvement is characterized in that all the devices inevitable for the lining operation including an operator's seat are effectively mounted on the transport car and that the rotating mechanism for rotating the spray pipe is provided with an oscillating means.
Due to the above construction, the lining apparatus of this invention can efficiently and uniformly apply the desired amount of refractory material onto the abraded or eroded portion of the refractory layers or a vessel or furnace.

Description

This is a division of applica-tion No. 276, 246 filed April 15, 1977.
This invention relates to an apparatus for applying a lining of refractory material, cement, heat-insulating material or other insulating materials over the refractory layers of a converter or a furnace inc]u~ing an electric furnace and an open-hearth furnace or a vessel with gxeat mobility and efficiency.
In conventional ~ining operations, the lining material is generally produce~ at a location remote rom the lining operation site and then is transferred to the operation site by means of a long compression supply tube wherein the long floor-laid tube hampers the movement of the lining device when it must move from one converter to another, resulting in an inefficient lining operation.
Furthermore, since the water storage tank, refractory material tank, compressor and the like which are required in the lining operation occupy a large floor area, the operation cannot be conducted efficiently or with adequate mobility.
In addition, these devices are usually located in spaced apart locations so that a central control system for the spraying apparatus is hard to achieve. Therefore, at least several wor~ers are requlred to operate the apparatus.
Meanwhile, in the lining operation, the lining apparatus is moved to a position adjacent to the upper open end of th~
~urnace. Subsequently, the long spray pipe is extended into the ~urnace and the spray nozzle attached to the extremity of the spray pipe is directed toward the abraded or eroded portion of the furnace lining and the desired amount of .~ .

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refractory material is sprayed onto the above portion so as to repair the lining of a furnace.
In this case, the operat:or controls the spray pipe while observing the movemen~ thereof.
However, the mere manipulation of the spray pipe i5 often inadequate to insure coverage of all of the abraded portion on the furnace lining because they are not all within the sprayable range of the spray pipe.
For example, when the spray nozzle is directed ~rom one abraded portion to another in some cases ~he spray pipe will come into contact with the upper periphery of the furnace i~ the lining apparatus is kept in the same position. In these cases, the apparatus as a whole must be moved a certain distance to prevent breaking the spray pipe.
The operation to move the apparatus conventionally requires that the operator gets o~f the apparatus or shifts his position on the apparatus thereby making the operation very cumbersome.
Furthermore, since the rotation of the spray pipe is effected manually by an ON-OFF switching operation, it is hardly possible ~o apply a refractory material uniformly or efficiently onto the abraded or eroded portion of a considerably large area. It is also considerably dif ficult for an operator to conduct two operations simultaneously, namely reciprocation and occilation of the spray pipe.
Accordingly, it is an object of the present invention to provide an apparatus for applying a lining onto the inner , , .
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It is another object of the present inv~ention to provide an apparatus for applyin~ a linin.g on.to the inner surface of a furnace wherein the spray no~zle ean u~iformly and efficiently apply refractory material onto the eroded or abraded portion of the inner surface o~ a furnace or vessel.
It is still another object of the present invention to provide an apparatus for applying a lining onto the inner surfaee of a furnaee and ine~udes a eentra~ control sys-tem.with whieh an operator ean manipulate all the deviees mounted on the transport car easi.ly and precisely.
It is still another objeet of the present invention to provide an apparatus for repairing the lining of a furnaee by means of whieh the entire spraying operation inelu~ing the ; manipulation of the spray pipe as well as the steering of the transport ear ean.be conducted by a sïngle operator while sitting on the seat mounted on the apparatus throughout the spraying operation.
The invention, as particularly claimed in the ~ instant divisional application is for use in an.apparatus for applying a refractory lining onto the inner surace of a furnaee eomprising- a transport car capable of mo~ing on a floor, a shooting pipe with a spray nozzle from which refractory material is sprayed onto the inner side of a furnace, a support means located on the transport car for pivotally supporting the shooting p-pe, a cylindrieal body pivotally mounted onto the top of the support and slidably encasing the sbooting pipe, a eontrol means imparting the rotation oE the shooting pipe relative to the eylindrical body, and a tank storing refraetory material therein and ineluding a means for supplying the - :

refractory ma-terial to the shooting ~ipe from.the tank, and is par-ticularly characterized in that the con:trol means includes a means for oscillating the rotation.of the shooting pipe relative to the cy~indrical body.
According to a preferred embodime~t of the in~ention, the oscillating means comprises: first and second spaced apart ring~like plates mounted on the outer pipe adjacen-t to one end of the cylindrical member, a selected number of circumferentially equidistant contact pads secured.to the outer circular surface of the first ring-like plate which faces t.he corresponding surface of the second ring-like pla-te, the corresponding surface of the second plate also having a selected number o~ contact pads secured thereto, and a limit switch provided wi.th two contact levers mounted on the cylindrical member, each of which lever is adapted to contact the contact pads of one of the ring-like plates so as to switch on and of the limit switch and thereby effect the rotatlon of the outer pipe relative to the cylindrical body in alternately opposed directions.
A preferred embodiment of the in~ention will now be described having reference to the appended drawings wherein:
. ~ Figure 1 is a top plan v:iew of the basic construction of the apparatus of this invention.
Figure 2 is a side view taken along the line I I of :~ : Figure 1, Figure 3 is another side view partially broken awa~ :
-.~ and taken along line II-II of Figure 1, Figure 4 is an enlarged-trans~erse cross-sectional ~iew ~ : .

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of slide means for sliding the outer spray pipe taken along the line III-III of Figure 3, Figure 5 is a side view of the slide means taken along the line IV-IV of Figure 4, Figure 6 is an enlarged plan view of slide means for sliding the inner spray pipe relative to the outer spray pipe taken along the ~ine V-V of Figure 3, Figure 7 is a longitudinal cross-sectional view of the slide means taken along the line VI-VI of Figure 6, Figure 8 is a schematic view of the skeleton structure of the lining apparatus showing the mechanism for steering the transport car, Figure 9 is an enlarged explanatory view showing the mounting position of the oscillating means on the cylindrical body, Figure 10 is a front view of a limit switch employed in the above oscillating means, Figure 11 is a cross-sectional side view of the above limit switch taken along the li.ne VII-VII of Figure 10.
The basic structure of the lining apparatus of this invention is firs~ described. Referring to Figure 1 through Figure 3, there is shown a transport car 2 provided with wheels 4 driven by hydraulically-operated motors so that the : car 2 is movable both backwards and forwardsO Above and substantially parallel to the transport car 2, there is `~: shown a spray pipe 8 consisting of an inner pipe 10 and~ an ~ outer pipe 12.

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The inner spray pipe 10 is provided with a spray nozzle 14 at the front extremity thereof ancl has the rear end thereof tightly connected with one end of a flexible hose 16 through.which regractory material in either dry or wet form is supplied thereto.
The other end of the fle:xible hose 16 is connected to a refractory material supply source which is described later.
The inner spray pipe 10 is sl.idably disposed inside the outer spray pipe 12 such that spray pipe 8 as a whole can be extended in a telescopic manner while the outer spray pipe 12 is rotatably and slidably disposed within a cylindrical member or body 18 which is disposed substantially at the front of the transport car 2. A power-operated motor 20 and a gear mechanism 22 which are both attached to the cylindrical body lB cause the rotation of the outer spray pipe 12 by way of a rotating boom 19. The rotating boom 19 forms a part of the cylindrical body lB.
This cylindrical body 18 is tiltably mounted by means of a pivot shaft 21 on the top of a vertical support structure 24 which in turn has the bottom end ixedly secured to ~he upper surface of~a turntable 26. A hydraulic cylinder 28 is diagonally disposed on the turntable 26 for the purpose of tilting the cylindrical body 18. This turntable 26 is supported by a plurality o~ roller means 30 which are disposed in a circle at the lower periphery of the turntable 26.
The turntalbe 26 further includes a worm wheel 32 which : :~
~ : meshes with a worm 34. The worm 34 is driven by a suitable ' ~

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driving means 35, such as a power-operated motor, ~o as to rotate the turntable 26 by way of the worm wheel 32.
On the turntable 26, a s~orage tank 36 for powder-like refractory material and another storage ~ank 38 for water are mounted by means of support columns 37 such tha~ the vertical axes of the tanks are aligned with the axis of the turntable 260 These tanks 36 and 38 are concentrically disposed one within the other such that the discharge outlet of the conical-shaped xefractory material tank 36 is disposed just below the center of the bottom of the water storage tank 380 - A heat insulating shield 41 is provided in front of the tank means.
Below the outlet 40 of the tank 36, a flow regulatiny valve 116 is disposed which regulates the amount of refractory material to be suppliad to the flexible hose 16.
The flow regulating valve 116 has an opening at the lower end thereof which, in turn, communicates with the flexible hose 16 throu~h the refractory material is charged to the inner spray plpe 10.
In order to ~ive flow energy to the refractory mat~rial which passes through the flexible h~se 16 and the inner spray pipe 10, an air jet gun 136 is provided at the lower end o~ the flow regulating valve 116 disposed oppso`ite to the opening 134. This air jet gun may be provided at any suitable position of~either the flexible hose, the spray pipe or the spray nozzle.

~ - 7 -. ,. ,, .. .. : . . : . . -~ ~ . .. , .: , , . , . . :', ' . ' The water storage tank 38 has a water outlet 138 at the bottom thereoE which is connected to one end of a cooling water supply tube 140. The cooling water supply tube 140 has its other end connected to an inlet ppening 142 formed in the outer spray pipe 12 at a location so that the water charged into spray pipe 8 cools the entire spray pipe 8 which is subjected to_high radiation heat temperatures during the spraying operation.
: The outer spray pipe 12 has another water outlet opening 144 which is connected to one end of a warm water return tube 146 wherein the water warmed during the circulation thereof within the spray pipe 8 is discharged into the return tube 146 by way.of the outlet opening 144.
The return tube 146 has its other end connected to the flexible hose 16 at the middle thereof by way of a three-port valve 148 wherein the warmed water which passes through the return tube 146 is mixed with the powder-like refractory material to produce refractory material in a wet slurry form which is charged into the inner spray pipe 10 by way of the : flexible hose 16.
At the reartof the transport car 2, an air compressor lS0 is provided which supplies compressed air to the air jet .~: gum 136, the water storage tank 33, the refractory-material storage tank 36 and other parts of the apparatus which : :: require compressed air. A diesel engine 151 for moving the transport car 2 is also mounted at the rear portion on the transport ca.r 2 along with its radiator 153.

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This air compressor 150 and the diesel engine 151 are both protected from dust and the like by a cover means 152.
In Figure 4 and Figure 5, the mechanism to slidably move the outer pipe 12 relative to the tiltable cylindrical hody 18 is shown wherein each roller shaft 154 which fixedly carries a pipe-propelling roller 156 and a spiral gear 158 in series has both en~s thereof journalled by ball bearings 160 which, in turn, rest within openings formed in the side walls of a casing 162. A spiral year 164 which is fixedly mounted on a drive shaft 166 of a power~operated motor 168 is meshed with spiral gears 158 so that the actuation of the motor 168 causes the rotation of the pipe-propelling rollers 156 which, in turn, move the outer spray pipe 12 forward or backward within and relative to the cylindrical body 18.
: Pressure to pinch the outer spray pipe 12 by the two opposing rollers 156 is adjusted by a bolt and nut means 170 disposed adjacent each ball-bearing 160.
In Figure 6 and Figure 7, the mechanism to slidably move the inner s~pray pipe 10 relative to the outer spray pipe 12 is shown wherein each of a pair of parallely-~: : disposed roller spaft 172 are integrally provided with a :: : :
: second pipe-propelling roller 174 and have both ends journalled by ball bearings 176 which rest in openings for~ed in the side walls of a casinq 178. Each roller shaft 172 is further provided:with a spiral gear 180 ~t the extension adja ent to " :
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: . .: .: : -motor 186 is meshed with spiraL gears 180 50 that the actuation of the motor 186 causes the rotation of the second pipe-propelling rollers 174 which, in turn, slidably move the inner spray pipe 10 forward or backward within and relative to the outer spray pipe 12~
To be more specific and exact, the second pipe-propelling rollers 17~ pinch the flexible hose 1~ (not the inner spray pip~ 10) as can be observed from Figure 7. When the above rollers 174 are rotated by the activation of motor 186, the flexible hose 16 which is now despressed in an elliptical hollow cross section is moved longitudinally in either forward or backward direction due to the friction at the inter-surface of rollers 174 and flexible hose 16.
As described previously, since the hose 16 is connected with the inner spray pipe 10, the inner spray pipe 10 moves backwards or forwards longitudinally along with the flexible hose 16.
The casing 178 is also provided with two opposing side rollers 18B which rotatably come into contact wi~h the expanded or distended round side of the hose 16 so as to guide the hose 16~
The pressure to ~inch the flexible hose 16 by the two opposing rollers 174 is adjusted by a bolt and nut meansl90 disposed above each ball bearing 176. ~piral gears 180 and lB2 are protected from dust or the like by a cover means 192 which is fixedly attached to the outer spray pipe 12 together with the casing 178.

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Referring to the means for controlling the apparatus of this shown in F.igure 8, a steering wheel 194 which steers the transport car 2 hydraulically by manipulating the rear wheels 4 is disposed adjacent to the upper portion of the refractory-material storage tank 36.
The mechanism to steet the transport car 2 has the following constructio~.
In Figure 8, ~wo lugs 196 which vertically move in opposite directions by the rotation of the steering handle 194 are attached to an endless chain 198 which is extended between a steering handle shaft 200 and a follower shaft 202. These lugs 196 are connected with a hydraulic power steering unit 204 by means of throttling wires 206. This power steering unit 204 which can steer the rear wheels 4 has one end connected with a rear-wheel steering link 208 and the other end pivotally secured to the frame of the transport car 2. Referring to other parts of this mechanism, numeral 210 indicates a throttling lug to which throttling wires 206 are connected, numeral 212 indicates casing tubes : .
which slidably enclose throttling wires 206 and numeral 214 indicates a hollo~ rotary shaft for running the elec~ric connections and hydraulic circuits as well as throttling wires.~ ~ ~
: : The construction of the oscillating means which features the present invention is now described hereinafter in~con~ùnction :~ with~Figure 9 through Figure 11, especially Figure 9 which shows the detail thereof.

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In the drawings, two spaced-apart circular ring plates 378a and 378b are formed onto the outer shooting pipe 12 adjacent to the pivot pin 41 which tiltably connects the cylindrical body 18 to the support column 24. Each riny plate 378a or 378b has a plurality of contacting pads 380a or 380b secured equidistantly circumferentially on the sides thereof which faces t~e corresponding side of the other ring plate. A fork-lever-shaped limit switch 382 which is provided - with two pressure detecting levers 384, 386 is fixedly mounted on the top of the cylindrical body 1`8 such that one detecting lever 384 is disposed in the rotational path of the row of contacting pads 380a while detecting lever 386 is disposed in the rotational pa~h of the row of connecting pads 38Ob.
The limit switch 382 which is especially applicable to the oscillating means of this embodiment further comprises contact rollers 388 and 390 attached to respective ends of the levers 384 and 386 and spring means 392 which tends to position the levers 384 and 386 in alignment with the body : of the limi~ switch 382 unless no contact pressure is applied to the contact ro~lers 388 and 390.
~ In this embodiment, when the outer shooting pipe 12 is ;~ rotated relative to the cylindrical body 18 by the actuation of the.motor 20 and gear mechanism 22, the contactiny pad : 380a disposed on the side o~ one ring plate 378a comes into contact with the corresponding contact roller 388 of the ~ limit switch and subsequently rotates the pressure detectinq ,: ~ -~ - 12 - -: ' -... , ~ . . . . . . .
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lever 384. When the lever 384 is rotated 90 degrees, the limit switch 382 initiates the rotation of the outer spray pipe 12 in the reverse direction.
The continued reverse rotation then.causes the contacting pad 380b on the side of ring 378b to contact with the correspond-ing contact roller 390 of the limit switch 382, and subsequently the limit switch 382 ~tops the reverse rotation after rotating the lever 386 by 90 degrees and starts the rotation of the outer cylindrical body 12 in the previous or first direction.
In this manner, the shooting pipe is oscillated periodically by a predetermined rotating or oscillating angle.
In Figure 1, the spray nozzle 14 which has its opening directed in an upward direction is oscillated a desired angle for applying the refractory material onto the inner upper portion of the furnace lining uniformly.
However it must be noted that the oscillating device provides the above oscillating movement of the shooting pipe regardless of the direction of the spraying opening of the spray nozzle.
Namely, when the inner lower portion of the furnace lining is require~ to be repaired, the spray nozzle must be directed from the upward position to the lower position.
In this case, the supply o~ electricity to the limit switch 382 is interrupted so as~not to nergize the limit switch 382 even when its con~act roller come into contact with the cont:act pad by the rotation of the outer spray pipe 12. For facilitating the above rotation of the outer shooting - ~3 -. .- . . . ~ .. . : . :-.. . .
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pipe 12 and also for preventing the breaking of the limit switch 382, the limit switch 382 is provided with two auxiliary pivot shafts 396 and 398 and a common shaft 400 which pivotally connects corresponding proximal ends of ~he two right-angled levers 384 and 386.
Each auxiliary pivot shaft is constructed such that it allows only one-way p~oting o:E the pressure detecting lever.
Due to the above construction, even when the vertically disposed contact roller of the inoperative limit switch 382 is pressed rearwardly by the trains of contacting pads 380a on one side of the ring-like plate 378~ the outer spray pipe 12 is rotated without breaking the lever 384 since the rotation of the lever 384 on the auxiliary shaft 396 allows the advancement of above contacting pads.
Accordingly, since the spray pipe is capable of oscillating in addition to rotating, tilting and sliding, the spraying operation by the l.ining apparatus of this invention is further enhanced.
The manner in which the apparatus of this invention is operated is as fo~lows.
The powder-like refractory material is discharged from the hopper like storage tank 36 by compressed air supplied from the air compressor 150 and the flow amount is regulated by the flow regulating valve 116. The discharged refractoxy material is conveyed through the flexible hose 16 with flow energy applied by the air jet from the air jet gun 136. The : , . ~ .

powder-like material subsequently passes throu~h spray pipe 8 and eventually is sprayed from the spray nozzle 14.
If the refractoxy material is required in a wet slurry form, the water which is supplied to spray pipe 8 from the water storage tank 38 for cooling the spray pipe 8 is available.
Namely, the cooling water is clischarqed from the water stora~e tank 38 by cQ~pressed air which is supplied from the air compressor lSO. The cooling water then passes through the cooling water supply tube 14~ into the spray pipe 8.
The water which is warmed after the abov~ cooling operation i5 discharged from the outlet 144 and passes through the warmed water return tube 146 and reaches the three port valve 148. By opening the three port valve 148, the powder-like refractory material from the refractory-material storage tank 36 and the warm water from the spray pipe 8 are mixed together forming refractory material in a wet slurry form at the junction where the return tube 146 and the flexible hose 16 meet. The thus produced slurry-like xeractory material is supplied to spray pipe 8 and finally is sprayed from the spray nozæle 14 onto the inner surface of the furnace.
t I~ the above operation, the spray pipe 8 is manupulated by the rotating mechanism, the feeding mechanism, the tilting mechanism and the turntable 26 such that the spray nozzle 14 secured to the extremity of the spray pipe 8 is directed toward the abraded portion of the inner surface of a ~urnace.
After above positioning of the spray nozzle 14, the spra~

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pipe 8 is automatically oscillated hy a desired rotating angle with the oscillating means disclosed heretofore.
Accordingly, the apparatus of this invention has the following advantages.
1. Since the spray pipe 8 can be automatically oscillated, the spray nozzle can fully and easily cover the abraded or eroded portiQn of the inner surface of a furnace which has, in general, a considerable area.

2. With the conventional apparatus, it is extremely difficult for an operator to efect two operations such as reciprocation and oscillation of the spray pipe simultaneously. Since above oscillating operation is conducted automatically in this invention, the operator can easily manipulate two operations, resulting in the improvement of the spraying operation.

3. Since the spray nozzle is oscillated, refractory material is uniformly applied onto the entire area of abraded portion of a furnace.

4. Since the oscillating angle can be adjusted, the optimal amoun~ of re~ractory material can be sprayed onto the above abraded portion.

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Claims (2)

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

1. In an apparatus for applying a refractory lining onto the inner surface of a furnace comprising:
(a) a transport car capable of moving on a floor, (b) a shooting pipe with a spray nozzle from which refractory material is sprayed onto the inner side of a furnace, (c) a support means located on said transport car for pivotally supporting said shooting pipe, (d) a cylindrical body pivotally mounted onto the top of said support and slidably encasing said shooting pipe, (e) a control means imparting the rotation of said shooting pipe relative to said cylindrical body, and (f) a tank storing refractory material therein and including a means for supplying said refractory material to said shooting pipe from said tank, the improvement characterized in that said control means includes a means for oscillating the rotation of said shooting pipe relative to said cylindrical body.

2. Apparatus according to claim 1, wherein said oscillating means comprises:
first and second spaced apart ring-like plates mounted on said outer pipe adjacent to one end of said cylindrical member, a selected number of circumferentially equidistant contact pads secured to the outer circular surface of said first ring-like plate which faces the corresponding surface of said second ring-like plate, said corresponding surface of said second plate also having a selected number of contact pads secured thereto, and a limit switch provided with two contact levers mounted on said cylindrical member, each of which lever is adapted to contact the contact pads of one of said ring-like plates so as to switch on and off said limit switch and thereby effect the rotation of said outer pipe relative to said cylindrical body in alternately opposed directions.