CA1196233A - Method for the gunning of basic gunning refractories - Google Patents
Method for the gunning of basic gunning refractoriesInfo
- Publication number
- CA1196233A CA1196233A CA000424050A CA424050A CA1196233A CA 1196233 A CA1196233 A CA 1196233A CA 000424050 A CA000424050 A CA 000424050A CA 424050 A CA424050 A CA 424050A CA 1196233 A CA1196233 A CA 1196233A
- Authority
- CA
- Canada
- Prior art keywords
- gunning
- nozzle
- refractory
- range
- basic
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Landscapes
- Furnace Housings, Linings, Walls, And Ceilings (AREA)
Abstract
A METHOD FOR THE GUNNING OF BASIC GUNNING REFRACTORIES
ABSTRACT OF THE DISCLOSURE
A method for the gunning of a basic gunning re-fractory in which there is carried out a cold or hot gunning coating or filling, by a nozzle mixing method, of a gunning refractory containing a basic refractory as aggregate, not more than 5% by weight of at least one of organic fibrous materials and inorganic fibrous materials, and as binder, at least one of phosphates and silicates, characterized in that the gunning re-fractory is fed to the nozzle portion under air pressures in the range 1-10 Kg/cm2, said gunning refractory is then discharged while being mixed at said nozzle portion with 5-25% by weight of water having the pressure in the range 0.5-5 Kg/cm2 and while being accompanied by a rotary motion, the gunning order at the start of discharging takes first air and water simultaneously and then the gunning refractory, and the distance between the nozzle end and the gunning surface is in the range 0.15 to 1.00 m while the gunning width is less than 1.00 m.
ABSTRACT OF THE DISCLOSURE
A method for the gunning of a basic gunning re-fractory in which there is carried out a cold or hot gunning coating or filling, by a nozzle mixing method, of a gunning refractory containing a basic refractory as aggregate, not more than 5% by weight of at least one of organic fibrous materials and inorganic fibrous materials, and as binder, at least one of phosphates and silicates, characterized in that the gunning re-fractory is fed to the nozzle portion under air pressures in the range 1-10 Kg/cm2, said gunning refractory is then discharged while being mixed at said nozzle portion with 5-25% by weight of water having the pressure in the range 0.5-5 Kg/cm2 and while being accompanied by a rotary motion, the gunning order at the start of discharging takes first air and water simultaneously and then the gunning refractory, and the distance between the nozzle end and the gunning surface is in the range 0.15 to 1.00 m while the gunning width is less than 1.00 m.
Description
This invention relates to a gunning method in which ba~ic gunning refractorie~ are suitably coated or filled to construction, vessel and apparatus for whi ch a refractory property is required~
These days unshaped refractorie~ are in quick spread due to their effectiveness ~or the improvement of working efficiency and there are introduced various working method~
utilizing vibration, centrifugal force, pres~ure force~
injection, gunning, etc9 as well a~ pouring9 and feeding under pressure. However9 in carrying out the working methods they have problems peculiar to each thereo~, and particularly for the gunning ~ethod there is le~t room o-~
improvement in obtaining an even adhesion layer w.ith good yield~ owing to rebound lo~s or droop.
In these circumstances the i~v~ntor of this invention has noticed that in gunning the basic refractories a dry gunning by nozzle mixing in which solid and liquid are mixed at the nozzle portion i~ ~uperior in obtaining the adhesion layers of e~cellent refractory and anti corrosive ~0 properties9 in cooperation with the adoption of basic refractorie~J to a wet gunning of using refractory slurry~
and as a result of having studied the adaptation of gunning refractories and gunning conditions he has been able to obtain an effective knowledge thereby to improve said problems concerning the coating or filling irre~pective of cold gunning or hot gunning and to ma~e the present 23~
invention in which the pre~ent gunning method can be con-veniently applied~
According to the present inverltion it i~ possible to form a strong, refractory layer at any place ~here refractory coating or filling is needed~ irrespective of plane, curved ~urfacey concave portion9 void portion, and the inner surface or the outer surface of tubular body, not to speak of melting furnaces such as blast furnace~
converter, electric furnace and reverberatory furnacs~
1~ ~essels for molten metal ~uch as ladle and tundish9 ve~sel3 for treating molten metals u3ed in Rheinetahl Hereu~ process and Dortmund Huttenunion process~ various indu~trial, heating furnaces, varioug accessorie~ and accessory positions of all these furnaces and ve~sel~ and appliances and appa-ratuses used in accompanying working. It is also possibleto resolve the problem such as rebound los~ or droop.
The object of the in~ention is to provide a method for the gunning of a ba~ic gunning refractory ln which there is carried out a cold or hot gunning coating or filling, by a nozzle mi~ing method, of a gunning refractory containlng a ba~ic refractory a~ aggregate, not more than 5~ by weight of at lea~t one of organic fibrou~ materials and inorganic fibrous materials, and as binder, at lea~t one of pho~phates and ~ilicates, characterized in that the gunning refractory is fed to the nozzle portion under air pre~sure~ in the range 1~10 Kg/cm2, said gunning refractory is then di.~charged ~g6Z33 while being mixed at said nozzle por-tion with 5~25~ by weight of water having the pressure in the range o. 5N5 Eg/cm2 and while being accompaniad by a rotary motionJ
the gunning order at the start of discharging takes first air and water simulta~eously and then the gunning re~rac-tory, and the distance between the nozzle end and the gunning sur~ace is in -the range 0.15 to 1~00 m whil~ tho gunning width is less than 1~00 mO
T~e reason of using basic refractorles as aggregate of the gunning refractory in ef~ecting -the present invention is that not only they are excellent in both re~ractorines~
and load softening point but particularly they e2hibit an excsllent m~lting-down resistancy against high temperature under the co-e~istence with basic slag~ and as the basic re~ractorie~ there can be used more than one selected ~rom among magnesia rafractories such as magnesia clinker~
dolomi-te clinker9 peridottite9 chrome magnesia and magnesia ~pinel9 and lime refractories such as sintered calcia, larnite and quick lime~
Organic and inorganic fibrous materials enhance the poro~i-ty of the gu~ning, coating layer, have smaller bulk specific density and improve the spalling resistancy of said coating layer so that at least one o~ both o~ them is mixed up to 5~0 by weight. Even with the addition 25 thereo~ by more than 5~o by weight any improved e~ect i~ not noticed but to the contrary it degrades the mechanical strength (compre~sive ~trength) A~ ~uch fibrous material~ the following can be mentioned.
That is, there can be used animal and ve~etation -fibers such as pulp, beaten paper~ cotton, wool~ silk and synthetic fibers, as organic fibrous material~9 and heat resistant fibers such as asbestos9 rock wool~ slag wool~
ceramic ~ibers and carbon fibers, as inorganic ~ibrou~
material~
Phosphates and silicates used as binder are known as binder for refractory aggregate, and there can be u~ad more th~n one ~elected from among alkali metal salts9 alkali ear-th metal salts and aluminium saltæ of ortho-pho~photiG acid 9 polypho~phoric acid~ methaphosphoric acid and ultraphosphoric acid with regard to phosphate~1 and 15 from among alkali metals of silicic acid with regard to silicates .
~ urther, it is possible to seleotively add~ to the gunning refractoryJ a carbonaceous material or lnorganic or organic vi~cosity-increasing agent besides the above materials~ as necessary.
The gunning refractory is fed to the nozzle portion under air pressures from 1 to 10 Kg/cm2 and di~charged while being mixed with water under pressures in the range 0.5~5 Eg/cm~ and while being accompanied by a rotary motion in said nozzle portion. The rea~on why the gunning re-fractory is fed under air pressures in the range 1 to 6~33 lO Xg/cm2 is that it i~ possible to optionally take the mode o-f discharging ranging from gunning and beating to a condition like flowlng-out, and with 1 Kg/cm2 the ai.r pressl~e is not sufficient while lO Kg~cm~ air pressure is too grea-t whereby neither of the case~ can achieve the ob~ect of the present invention. Preferably~ to prevent the nozzle from blocking, the gunning order at the time of ~tarting the discharge i~ brought in such a way that the air and the water are discharged simultaneously and then the gunning refractory is discharged.
The opening for supplying water in said nozzle portion can be provided by single or plurarity in optional position and mode in the nozzle portion to effect a nozzle mixin~. Preferably the amount of supplying water i~ from 5 to 25~ by weight to the gunning re~rac~ory, less tha~
5% by wei~ht of water is too little to make a complete mi~ing and to have a sufficient adhesion ~trength while more than 25~ by wsight is too great so a~ to flow the gunning refractory away whereby neither of the ca~es forms a sufficient coati~g layer~
It is one of the important con~titutional feature~
of the invention to di~charge ~aid mi2ture with a rotary motion, and as a method of making the rotary motion it is effective t for example, to provide the opening for feeding the gunning refractory to the nozzle portion~
tangentially to the cross section of said nozzle~ and it is also preferable to use a plate like guide plate along the rotational direction within the nozzle portion, by alone or in co-use with said opening. ~urther, it is effective, a~ an auxiliary mean~ for imparting the rotary S motion, to arrange the opening or openings for supplying water in the tangential direction along the rotational direction of said gunning refractory. In any case it i~
capable of optionally selecting the rotational direction of said gunning refractory in the de~igning proces~ of nozzle.
As t~e gunning conditions regarding the nozzle operation it is preferable that the distance from the nozzle to the gunning surfaca is in the range 0~15 to 1.00 m~ and with less than 0.15 m distance the gunnlng refractory is gre.tly lost by rebound while if -the dis-tance exceeds 1.00 m the discharging energy is lowered,æo that any of ~uch cases does not form a prefer&ble coating layer. Furthermore, the rea~on why the gunning width of the gunning refractory in the guNning surface i~ le~s than 1.00 m is that it i~ related to said dls--tance bstween the nozzle and the gunning surface, and incase the gunning width is more than 1.00 m it is no longer pos~ible to obtain a u~eful coating layer. The adjustable range of more suitable gunning width is from 0~05 to 1.00 m.
Preferably the angl~ to the gunning surface of the nozzle may be as near right angle (vertical) as possible, but practica.lly an angle of more than 45 degrees will ~uf~ice since it hardly cau~es rebound and it i~ almost 3ame as in right angle~ Said angle of the nozæle can be changed by turning the noz~le arm or curving or bending the tip portion of the no~zle~ A~ ~e operating apparatu~
it will be proper to use an automatic operation apparatu~
provided ~ith variou~ functions such as travelling, moving sidewi~e and vertically and turning, Ref'erring to the temperature of the gunning ~ur~ace J
the preferable temperature range wherein the pre~ent in-vention can be effected is O~l,OOO~C whichev~r in coldgunnlng or hot gunning. If it i3 below O~C the gunning freezes and i~ it exceeds l,000C the water content quickly evaporate3 ~o that in both case~ it becomes difficult to gun the refractory.
Preferably the discharge amount from the nozzle i~
in the range 5~25 Eg/min, and with less than 5 Kg/min or with 25 Kg/min the di~charge amount i~ too little or too much whereby in both the ca~e~ gunning become~ impo~3ible.
The nozzle to the gunning sur~ace can move in one of the optional directio~s accompanied by reciprocal move-ment and spiral movement~ Naturally a rever~e case may occur to the cese in which the moving direction of sald nozzle accord~ wi-th the rotational movement direction o~
~aid gunning re~ractory, but in any cas~ the objec-t o~ the present invention i~ achievable. I-t i~ pre~erable that the moving ~peed o-~ the no~le to the gunning ~ur~ace i~
30 m/min during the gunning~ and to be speedier than 30 m/min is too fa~t so that the adhesion of -the gunning refractory becomes incomplete due to the rebounding o~
the re~ractory from the gunning surface~
Whether to move the nozzle during the gunning by hand or automatica~ly does not reversely affect the function and effect of the invention if the ~ariety of thc abov~
condition~ are sati~fied, but from the safety point of view of working it would be better to use an automated machineO
Now referring to the nozzle employed in the method of this application, it would be preferable to provide at the peripheral edge of the tip air i~jection ports which form an air curtain at the tip in the gunning direction, so aæ to pre~ent the gunning refractory -from ~cattering.
Further, to prevent the nozzle from blocking~ it would aleo be preferable that gunning is carried out with a nor~zle, at least part of whlch is provided with a rotational machani~m.
The following is an egample in which the present inv~ntion was carried out for lining a surface of re-fractory bricks of a tundish for continuou~ steel ca9ting.
A gunning was effected in such manner that a gunning refractory consi~ting of 2 mi~ture of 86~ by weight o~
magnesia clinkerg 4~ by wei~ht o~ rock wool~ 3~o by weight of waste cotton, 4~ by weight of sodium primary phosphate and 3~o by weight of ~odium methasilicate, wa~ fed to the ~6~33 nozzle portion under an air pre~q~ure of 5~3 ~g/cm2 ~rom the tangential direction to the cros3 3ection of thc nozzle, while being ~upplied 11% by weight o~ water of the gunning re~ractory from the circum~erential aperture~
in said nozzl.e portion. Retaining the distance bet~een the nozzle and the gunning ~ur~ace with 0,4 m ~nd the gunning angle with approximately 90 the nozzle wa~ mo~ed ~plrally along the inner circumference at the ~pe~d of 1 m/min. Moreover~ the temperature at the gunning ~ur~ace just be-fore the ~tarting of the gunning was 500DC9 when a coating layer of 0~2 m adhesion width was obtained in the di3charge amount o~ 15 Kg/mi~ Under ~uch condition~ the gunning refractory wa~ di~charged while being mixed with water and being accompani2d by a rotary motion9 the gunning re~ractory wa~ adhered uniformly and ~moothly to the g~nni~g surface ~ince being subject to a recti~ying control by an interm~diate ~qu~e~ing portion9 thP rebound lo~ was only 10~ though it wa~ 30~40~ according to conventional m~thod9 and droop ~a~ not noticed thereby improving the con~entional problem~, An average thickne~ o~ 0.015 m wa~ made to the coatin~ layer of the tundi~h and the tundi~h wa~ preheated at l,000C ~or 30 mi~ute~ ~u~t before ite operatio~ but craking or any other phPnomena occurred~ the coating layer could stand the use of sontinuou~contl~uou~ ca~ti~g~
of 5 oharge~ of 200 ton ~teel melt~ and the remaining 3~
minimum thickness of the coating layer wa~ ~till 0. 01 m at the finish of the ca3ting so that a sati~fiable re~ult could be ob tained~
~ 10
These days unshaped refractorie~ are in quick spread due to their effectiveness ~or the improvement of working efficiency and there are introduced various working method~
utilizing vibration, centrifugal force, pres~ure force~
injection, gunning, etc9 as well a~ pouring9 and feeding under pressure. However9 in carrying out the working methods they have problems peculiar to each thereo~, and particularly for the gunning ~ethod there is le~t room o-~
improvement in obtaining an even adhesion layer w.ith good yield~ owing to rebound lo~s or droop.
In these circumstances the i~v~ntor of this invention has noticed that in gunning the basic refractories a dry gunning by nozzle mixing in which solid and liquid are mixed at the nozzle portion i~ ~uperior in obtaining the adhesion layers of e~cellent refractory and anti corrosive ~0 properties9 in cooperation with the adoption of basic refractorie~J to a wet gunning of using refractory slurry~
and as a result of having studied the adaptation of gunning refractories and gunning conditions he has been able to obtain an effective knowledge thereby to improve said problems concerning the coating or filling irre~pective of cold gunning or hot gunning and to ma~e the present 23~
invention in which the pre~ent gunning method can be con-veniently applied~
According to the present inverltion it i~ possible to form a strong, refractory layer at any place ~here refractory coating or filling is needed~ irrespective of plane, curved ~urfacey concave portion9 void portion, and the inner surface or the outer surface of tubular body, not to speak of melting furnaces such as blast furnace~
converter, electric furnace and reverberatory furnacs~
1~ ~essels for molten metal ~uch as ladle and tundish9 ve~sel3 for treating molten metals u3ed in Rheinetahl Hereu~ process and Dortmund Huttenunion process~ various indu~trial, heating furnaces, varioug accessorie~ and accessory positions of all these furnaces and ve~sel~ and appliances and appa-ratuses used in accompanying working. It is also possibleto resolve the problem such as rebound los~ or droop.
The object of the in~ention is to provide a method for the gunning of a ba~ic gunning refractory ln which there is carried out a cold or hot gunning coating or filling, by a nozzle mi~ing method, of a gunning refractory containlng a ba~ic refractory a~ aggregate, not more than 5~ by weight of at lea~t one of organic fibrou~ materials and inorganic fibrous materials, and as binder, at lea~t one of pho~phates and ~ilicates, characterized in that the gunning refractory is fed to the nozzle portion under air pre~sure~ in the range 1~10 Kg/cm2, said gunning refractory is then di.~charged ~g6Z33 while being mixed at said nozzle por-tion with 5~25~ by weight of water having the pressure in the range o. 5N5 Eg/cm2 and while being accompaniad by a rotary motionJ
the gunning order at the start of discharging takes first air and water simulta~eously and then the gunning re~rac-tory, and the distance between the nozzle end and the gunning sur~ace is in -the range 0.15 to 1~00 m whil~ tho gunning width is less than 1~00 mO
T~e reason of using basic refractorles as aggregate of the gunning refractory in ef~ecting -the present invention is that not only they are excellent in both re~ractorines~
and load softening point but particularly they e2hibit an excsllent m~lting-down resistancy against high temperature under the co-e~istence with basic slag~ and as the basic re~ractorie~ there can be used more than one selected ~rom among magnesia rafractories such as magnesia clinker~
dolomi-te clinker9 peridottite9 chrome magnesia and magnesia ~pinel9 and lime refractories such as sintered calcia, larnite and quick lime~
Organic and inorganic fibrous materials enhance the poro~i-ty of the gu~ning, coating layer, have smaller bulk specific density and improve the spalling resistancy of said coating layer so that at least one o~ both o~ them is mixed up to 5~0 by weight. Even with the addition 25 thereo~ by more than 5~o by weight any improved e~ect i~ not noticed but to the contrary it degrades the mechanical strength (compre~sive ~trength) A~ ~uch fibrous material~ the following can be mentioned.
That is, there can be used animal and ve~etation -fibers such as pulp, beaten paper~ cotton, wool~ silk and synthetic fibers, as organic fibrous material~9 and heat resistant fibers such as asbestos9 rock wool~ slag wool~
ceramic ~ibers and carbon fibers, as inorganic ~ibrou~
material~
Phosphates and silicates used as binder are known as binder for refractory aggregate, and there can be u~ad more th~n one ~elected from among alkali metal salts9 alkali ear-th metal salts and aluminium saltæ of ortho-pho~photiG acid 9 polypho~phoric acid~ methaphosphoric acid and ultraphosphoric acid with regard to phosphate~1 and 15 from among alkali metals of silicic acid with regard to silicates .
~ urther, it is possible to seleotively add~ to the gunning refractoryJ a carbonaceous material or lnorganic or organic vi~cosity-increasing agent besides the above materials~ as necessary.
The gunning refractory is fed to the nozzle portion under air pressures from 1 to 10 Kg/cm2 and di~charged while being mixed with water under pressures in the range 0.5~5 Eg/cm~ and while being accompanied by a rotary motion in said nozzle portion. The rea~on why the gunning re-fractory is fed under air pressures in the range 1 to 6~33 lO Xg/cm2 is that it i~ possible to optionally take the mode o-f discharging ranging from gunning and beating to a condition like flowlng-out, and with 1 Kg/cm2 the ai.r pressl~e is not sufficient while lO Kg~cm~ air pressure is too grea-t whereby neither of the case~ can achieve the ob~ect of the present invention. Preferably~ to prevent the nozzle from blocking, the gunning order at the time of ~tarting the discharge i~ brought in such a way that the air and the water are discharged simultaneously and then the gunning refractory is discharged.
The opening for supplying water in said nozzle portion can be provided by single or plurarity in optional position and mode in the nozzle portion to effect a nozzle mixin~. Preferably the amount of supplying water i~ from 5 to 25~ by weight to the gunning re~rac~ory, less tha~
5% by wei~ht of water is too little to make a complete mi~ing and to have a sufficient adhesion ~trength while more than 25~ by wsight is too great so a~ to flow the gunning refractory away whereby neither of the ca~es forms a sufficient coati~g layer~
It is one of the important con~titutional feature~
of the invention to di~charge ~aid mi2ture with a rotary motion, and as a method of making the rotary motion it is effective t for example, to provide the opening for feeding the gunning refractory to the nozzle portion~
tangentially to the cross section of said nozzle~ and it is also preferable to use a plate like guide plate along the rotational direction within the nozzle portion, by alone or in co-use with said opening. ~urther, it is effective, a~ an auxiliary mean~ for imparting the rotary S motion, to arrange the opening or openings for supplying water in the tangential direction along the rotational direction of said gunning refractory. In any case it i~
capable of optionally selecting the rotational direction of said gunning refractory in the de~igning proces~ of nozzle.
As t~e gunning conditions regarding the nozzle operation it is preferable that the distance from the nozzle to the gunning surfaca is in the range 0~15 to 1.00 m~ and with less than 0.15 m distance the gunnlng refractory is gre.tly lost by rebound while if -the dis-tance exceeds 1.00 m the discharging energy is lowered,æo that any of ~uch cases does not form a prefer&ble coating layer. Furthermore, the rea~on why the gunning width of the gunning refractory in the guNning surface i~ le~s than 1.00 m is that it i~ related to said dls--tance bstween the nozzle and the gunning surface, and incase the gunning width is more than 1.00 m it is no longer pos~ible to obtain a u~eful coating layer. The adjustable range of more suitable gunning width is from 0~05 to 1.00 m.
Preferably the angl~ to the gunning surface of the nozzle may be as near right angle (vertical) as possible, but practica.lly an angle of more than 45 degrees will ~uf~ice since it hardly cau~es rebound and it i~ almost 3ame as in right angle~ Said angle of the nozæle can be changed by turning the noz~le arm or curving or bending the tip portion of the no~zle~ A~ ~e operating apparatu~
it will be proper to use an automatic operation apparatu~
provided ~ith variou~ functions such as travelling, moving sidewi~e and vertically and turning, Ref'erring to the temperature of the gunning ~ur~ace J
the preferable temperature range wherein the pre~ent in-vention can be effected is O~l,OOO~C whichev~r in coldgunnlng or hot gunning. If it i3 below O~C the gunning freezes and i~ it exceeds l,000C the water content quickly evaporate3 ~o that in both case~ it becomes difficult to gun the refractory.
Preferably the discharge amount from the nozzle i~
in the range 5~25 Eg/min, and with less than 5 Kg/min or with 25 Kg/min the di~charge amount i~ too little or too much whereby in both the ca~e~ gunning become~ impo~3ible.
The nozzle to the gunning sur~ace can move in one of the optional directio~s accompanied by reciprocal move-ment and spiral movement~ Naturally a rever~e case may occur to the cese in which the moving direction of sald nozzle accord~ wi-th the rotational movement direction o~
~aid gunning re~ractory, but in any cas~ the objec-t o~ the present invention i~ achievable. I-t i~ pre~erable that the moving ~peed o-~ the no~le to the gunning ~ur~ace i~
30 m/min during the gunning~ and to be speedier than 30 m/min is too fa~t so that the adhesion of -the gunning refractory becomes incomplete due to the rebounding o~
the re~ractory from the gunning surface~
Whether to move the nozzle during the gunning by hand or automatica~ly does not reversely affect the function and effect of the invention if the ~ariety of thc abov~
condition~ are sati~fied, but from the safety point of view of working it would be better to use an automated machineO
Now referring to the nozzle employed in the method of this application, it would be preferable to provide at the peripheral edge of the tip air i~jection ports which form an air curtain at the tip in the gunning direction, so aæ to pre~ent the gunning refractory -from ~cattering.
Further, to prevent the nozzle from blocking~ it would aleo be preferable that gunning is carried out with a nor~zle, at least part of whlch is provided with a rotational machani~m.
The following is an egample in which the present inv~ntion was carried out for lining a surface of re-fractory bricks of a tundish for continuou~ steel ca9ting.
A gunning was effected in such manner that a gunning refractory consi~ting of 2 mi~ture of 86~ by weight o~
magnesia clinkerg 4~ by wei~ht o~ rock wool~ 3~o by weight of waste cotton, 4~ by weight of sodium primary phosphate and 3~o by weight of ~odium methasilicate, wa~ fed to the ~6~33 nozzle portion under an air pre~q~ure of 5~3 ~g/cm2 ~rom the tangential direction to the cros3 3ection of thc nozzle, while being ~upplied 11% by weight o~ water of the gunning re~ractory from the circum~erential aperture~
in said nozzl.e portion. Retaining the distance bet~een the nozzle and the gunning ~ur~ace with 0,4 m ~nd the gunning angle with approximately 90 the nozzle wa~ mo~ed ~plrally along the inner circumference at the ~pe~d of 1 m/min. Moreover~ the temperature at the gunning ~ur~ace just be-fore the ~tarting of the gunning was 500DC9 when a coating layer of 0~2 m adhesion width was obtained in the di3charge amount o~ 15 Kg/mi~ Under ~uch condition~ the gunning refractory wa~ di~charged while being mixed with water and being accompani2d by a rotary motion9 the gunning re~ractory wa~ adhered uniformly and ~moothly to the g~nni~g surface ~ince being subject to a recti~ying control by an interm~diate ~qu~e~ing portion9 thP rebound lo~ was only 10~ though it wa~ 30~40~ according to conventional m~thod9 and droop ~a~ not noticed thereby improving the con~entional problem~, An average thickne~ o~ 0.015 m wa~ made to the coatin~ layer of the tundi~h and the tundi~h wa~ preheated at l,000C ~or 30 mi~ute~ ~u~t before ite operatio~ but craking or any other phPnomena occurred~ the coating layer could stand the use of sontinuou~contl~uou~ ca~ti~g~
of 5 oharge~ of 200 ton ~teel melt~ and the remaining 3~
minimum thickness of the coating layer wa~ ~till 0. 01 m at the finish of the ca3ting so that a sati~fiable re~ult could be ob tained~
~ 10
Claims (12)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A method of gunning a basic gunning refrctory by which there is provided on a cold or hot gunning surface, by a nozzle mixing method, a gunned coating or filling of a gunning refractory containing a basic refractory as aggre-gate, not more than 5% by weight of each of at least one of organic fibrous materials and inorganic fibrous materials, and as a binder, at least one of phosphates and silicates, characterized in that the gunning refractory is fed to a nozzle portion under air pressure in the range of 1-10Kg/cm2, the gunning refractory is then discharged while being mixed at the nozzle portion with 5-25% by weight of water under pressure in the range of 0.5-5Kg/cm and while a rotary motion is imparted thereto, the gunning being com-menced by first discharging air and water simultaneously and then with the gunning refractory, and the distance between the nozzle discharge end and the gunning surface is in the range of 0.15 to 1.00m while the spray width is less than 1.00m.
2. A method as described in claim 1 wherein the temperature of the gunning surface is in the range of 0-1,000 degrees C. for cold or hot gunning.
3. A method as described in claim 1 wherein the gun-ning refractory is imparted with a rotational motion in a predetermined, optional direction in the nozzle portion.
4. A method as described in claim 1 wherein the nozzle discharge rate is in the range 5-25 Kg/min.
5. A method as described in claim 4 wherein the spray width is in the range of 0.05-1.00 m.
6. A method a described in claim 1 wherein the nozzle is moved in any optional one direction being accompanied by a reciprocating movement and a spiral movement.
7. A method as described in claim 4 wherein the travel speed of the nozzle is slower than 30 m/min.
8. A method as described in claim 7 wherein there is used a nozzle provided with air injection apertures which form an air curtain in the discharging direction.
9. A method as described in claim 8 wherein the gunning is carried out by rotating at least a part of the nozzle.
10. A method as described in claim 1 wherein the spray width is in the range of 0.05-1.00 m.
11. A method as described in claims 1, 5 and 10 wherein the travel speed of the nozzle is slower than 30 m/min.
12. A method as described in any one of claims 1, 4 and 5 wherein there is used a nozzle provided with air in-jection apertures which form an air curtain in the dis-charging direction.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000424050A CA1196233A (en) | 1983-03-21 | 1983-03-21 | Method for the gunning of basic gunning refractories |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000424050A CA1196233A (en) | 1983-03-21 | 1983-03-21 | Method for the gunning of basic gunning refractories |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1196233A true CA1196233A (en) | 1985-11-05 |
Family
ID=4124832
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000424050A Expired CA1196233A (en) | 1983-03-21 | 1983-03-21 | Method for the gunning of basic gunning refractories |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1196233A (en) |
-
1983
- 1983-03-21 CA CA000424050A patent/CA1196233A/en not_active Expired
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA2187623C (en) | Method of protecting ladle linings | |
| US4461789A (en) | Method of gunning basic gunning refractories | |
| CA1196233A (en) | Method for the gunning of basic gunning refractories | |
| US3416779A (en) | Composite refractory lining for basic oxygen furnace | |
| Goto et al. | Progress and perspective of refractory technology | |
| US3897256A (en) | Refractory lining mixture for hot metallurgical vessels | |
| US3351460A (en) | Method for prolonging the life of refractory linings in furnaces of the kaldo, linz-donowitz, de may or basic or acid converter types | |
| EP0123755A1 (en) | Unshaped and refractory composition for coating or filling | |
| EP0121029B1 (en) | A method for the gunning of basic gunning refractories | |
| CN106242596A (en) | A kind of hot-metal bottle antiseized spray paint and preparation method thereof and spraying method | |
| JP2000344581A (en) | Wet-spraying material for molten steel ladle and method for spraying | |
| CA1195095A (en) | Process for lining electric steel furnaces | |
| US3911175A (en) | Method and a device for gunniting converter | |
| US2683032A (en) | Basic lined cupola | |
| US6514312B2 (en) | Steelmaking slag conditioner and method | |
| RU2179908C1 (en) | Method for protecting ladle car from growing over at melting irons with increased content of titanomagnetites | |
| Ito et al. | Technical development of refractories for steelmaking processes | |
| Gerling et al. | Fully automatic refractory maintenance system | |
| JPH02403B2 (en) | ||
| SU1713939A1 (en) | Compound for gun-concreting metallurgical equipment | |
| UA25657U (en) | Method for vessel reline | |
| JPS6221753B2 (en) | ||
| JP2022006385A (en) | Top-blown lance for converter dephosphorization treatment and converter blowing method | |
| SU1278321A1 (en) | Method of treating melt and arrangement for effecting same | |
| JPH0160523B2 (en) |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEC | Expiry (correction) | ||
| MKEX | Expiry |