CZ9903589A3 - Lance for heating or ceramic welding as well as process of alternative making flame - Google Patents

Abstract

Lancet for heating or welding with ceramics, e.g. applying a heating flame to the surface and then spraying sand or similar solid material in the carrier gas, incinerating, includes a head portion (10, 20) with a central main bore (23) in the nozzle end, with ceramic welding materials including particulate material containing oxidizable particles and carrier gas incineration is introduced at the rear end, passes through through the inner channel (13) and the main bore (23) and protrude from the nozzle end is characterized by the head portion comprising at least one channel (28) for transporting the mixture fuel gas and combustion promoting gas, wherein each channel (28) has an opening (29) in the lancet nozzle end and is provided with a fuel gas introducing portion (28a) and portions (28b) for introducing combustion-promoting gas. Way alternative flame creation, the essence of which lies in that the combustion gas and gas fed to the gas they connect at the rear end in the channel (28) and exit for creating a flame at the nozzle end of each channel (28). The lancet makes it possible to apply intensive high pressure to the surface and then immediately perform the ceramic welding.

Description

Modified page

LANCET FOR CERAMIC HEATING OR WELDING )ι'ζεΜι '

Technical field

The invention relates to a lancet device for heating or ceramic welding purposes, in particular for generating a heating flame or for conveying sand or the like particulate material in a combustion promoting gas.

In particular, the invention relates to a lancet mouth configuration used alternatively for flame generation or for ceramic welding. The invention also covers a method using this lancet device.

BACKGROUND OF THE INVENTION

In ceramic welding, a mixture of refractory solid particles and solid fuel particles of metal or semi-metal, for example aluminum or silicon, is injected in a carrier gas stream, typically oxygen, against the surface. The fuel particles react with oxygen in a highly exothermic manner to form refractory oxides, releasing sufficient heat against the surface to melt at least the surface of the refractory particles and forming a coherent refractory. Such ceramic welding is described in GB patent applications 1 330 894 and 2 170 191 (Glaverbel).

Ceramic welding can be used to form refractory products, such as a block of special shape,

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The treated side, however, is more often used to form coatings or to repair bricks or walls made of refractory oxide materials. It is particularly useful for repairing or reinforcing existing refractory furnace structures, for example glass furnace walls or coke ovens, especially since the repair can be performed while the furnace is operating.

To reach a repair area that can be a few meters away from the operator, the lancets are long and require support devices, such as flexible gas and particulate feed lines. As a rule, they also have a water-cooled jacket with connected cooling water inlets. Lancets can thus be very heavy and difficult to handle, and in some cases require special scaffolding and attached lifting equipment to bring them into working position.

When performing repairs, it is generally necessary to prepare the surface to be repaired, for example to remove loose or foreign material to provide a solid base for adhering the repair mass. In some cases, the repaired surface is treated by introducing combustion gas into the repaired area to incinerate undesirable deposits.

Lancets for use for such purification purposes are known. EP-A-0069286 relates to a lancet for flame spray treatment of a metal refining vessel, including a furnace bottom cleaning device which supplies oxygen to a desired location. The burners are also known for cleaning refractory surfaces.

Another example of a flame spray device is US 4,363,443, wherein the flame spray gas burner comprises a replaceable nozzle portion.

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Modified page

As is apparent from the refractory nature of the base, it is desirable to use an intense cleaning flame which, if desired, can quickly melt a portion of the repaired surface and leave a fresh surface to be repaired. Particularly in the case of glass furnaces, the glass phase may be present as a molten glass residue, as an exudate of the refractory binder phase, or as a result of the deposition of refractory material dust from the vitrifiable material mixture introduced into the glass melting tank. The glass phase is particularly often found in refractory blocks at the molten glass level line in a glass furnace. These blocks are generally of high quality Zac refractory.

Conventional repair of damaged or worn refractory walls within an oven, such as a glass furnace, by first flame treating the wall surface, followed by spraying the ceramic welding powder mixture, typically involves more torch or ceramic welding lancet manipulations. The steps of removing the torch and inserting and directing the ceramic welding lancet to the flame-treated area can be difficult and time consuming. The resulting residence times, which can generally be 20 to 60 minutes, are also long enough for the glass phase to reappear on the wall surface. In addition, the curing effect having a less potent refractory structure is lost.

Patent application GB 2237803 relates to a ceramic welding nozzle having a central opening for welding material in a gaseous fluid, such as air, and combustion means adjacent a nozzle outlet for injecting a flammable liquid, such as propane, butane or acetylene,

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- ⁴ - ...... Treated side into gaseous fluid. The combustion means primarily serves to promote the formation of the weld by heating the welding particles and the refractory substrate. The combustible fluid mixes with the gaseous fluid from the central orifice and reacts there with oxygen to form a heating flame near the repair area.

The flame can be used simply to preheat the repaired surface, but the defined nozzle itself does not provide an intense flame, the flammable fluid is introduced into the gaseous fluid from a single central opening and disperses over a relatively wide area. This system does not provide for cleaning of the surface before repair nor does it allow it.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a lancet having a built-in ability to deliver an intense flame independently of its function for ceramic welding or the like.

The invention provides an apparatus for alternatively flame forming or ceramic welding, comprising a single tubular lancet having a nozzle end and a rear end, with a head portion with a central main bore in the nozzle end, wherein ceramic welding materials comprising particulate material comprising oxidizable particles and carrier gas supporting combustion, introduced at the rear end, passes through the main bore and exits in the nozzle, characterized in that the head portion (10 + 20) further comprises at least one channel (28) for conveying a mixture of fuel and combustion promoting gas, each channel ( 28) has an opening (29) in the lancet nozzle and is provided with a portion (28a) for introducing fuel gas and a portion (28b) for

78271 (78271a.doc) ·· · * ··. · · · ·

:. . .. ·. ··. A modified combustion insertion stage, wherein the fuel gas and the combustion support gas supplied at the rear end combine in the channel (28) and exit to form a flame at the nozzle end of each channel (28), and in that the head portion is formed two parts, an inner block (20) comprising a main bore (23) and (28) for fuel and combustion-promoting gas, and outlet openings of said bore and channels (29), and an outer block (10) including supply passages to the an internal block of respective feed lines for particulate material with carrier gas (13), for fuel gas and for combustion-promoting gas (15, 16).

The invention also provides a method of alternatively flame forming or ceramic welding, using a tubular lancet having a nozzle end and a rear end, with a head portion with a central main bore in the nozzle end, wherein ceramic welding materials comprising particulate material comprising oxidizable particles and combustion-promoting carrier gas is introduced at the rear end, passes through the main bore and exits in the nozzle, characterized in that the mixture of fuel gas and combustion promoting gas is conveyed through at least one channel in the head portion other than the main bore, the head portion further comprising at least one channel having an opening in the lancet nozzle, wherein the fuel gas and the combustion promoting gas separately supplied at the rear end are combined in the channel and exit to form a flame at the nozzle end of each channel.

By separating the flame-forming gases from the main gas stream, the invention provides a homogeneous mixing of these gases in optimal proportions to produce the desired flame and allows complete flame independence from the welding function

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9 9 on the left side ϋρ ceramic, which serves the current through the main opening. Thus, the flame may first serve for cleaning or other treatment of the target surface, and then the main orifice for ceramics welding may begin to function immediately. Thus, the problems of handling a lancet or different lancets between two different purposes are eliminated, and the second purpose may begin to function before any heat loss from the target surface occurs.

The invention is also well suited for the use of high flame temperature fuel gases in easily controllable proportions to achieve the desired flame intensity. Generally, acetylene and mixtures of acetylene, such as tetrene ™, are used, since they allow to easily reach flame temperatures of more than 2000 ° C. Other gases, such as propane, may also be suitable for some applications. The combustion promoting gas is preferably oxygen per se.

For most purposes, it is preferred that the main bore coincides substantially with the central axis of the head portion, and a plurality of fuel gas and combustion-promoting gas channels are arranged around the main bore. The channels are preferably evenly distributed around the main bore and their number is preferably sufficient to form a continuous annular flame, thereby ensuring heating of the entire treated surface. For a ceramic welding lancet of conventional size, the number of channels to achieve such a flame is generally 12. The channels are preferably parallel to each other, but may be slightly divergent with each other, for example at an angle of 2-3 ° from the head axis. The resulting outwardly defined flame shape aids the movement of the molten material away from the treatment zone. The removal of this molten material is also facilitated by the use of an intense high pressure flame such as

78271 (78271a.doc) • · • · _t • Adjusted side is possible invention.

Preferably, each of the plurality of fuel gas and combustion gas channels is a branched channel, with two power arms connecting to form a single outlet. The supply branches are supplied separately with fuel and combustion-promoting gas from the rear end of the lancet, and the gases are combined in the head and exit completely mixed in the outlet opening.

The preferred internal diameter of the channel at the lancet nozzle end depends on the fuel gas selected. For gases with a high flame temperature, the diameter is preferably in the range of 1.5 to 3 mm. For acetylene and tetrene, the diameter is generally in the range of 1.5 to 2.5 mm, and for propane it is generally 2.0 to 3.0 mm.

The preferred fuel / combustion assist pressure is dependent on the configuration of the burner and is governed by the nature of the substrate being treated. Usually, it is measured, and can be easily adjusted, in the respective fuel and combustion fuel storage cylinder. This setting also allows pressure to be selected to maintain the flame attached to the lancet nozzle. When using industrially pure oxygen as the combustion promoting gas, the regulated pressure of the gas supplied from the cylinder is generally about 4.0 to 5.0 bar. Typically, the fuel gas is supplied at a lower pressure, for example 2.0 to 2.5 bar (0.2 to 0.25 MPa) and at a lower velocity than the combustion promoting gas, for example by developing a supporting gas in the branched feed channel described above. combustion at mixing point suction effect on fuel gas.

For industrial applications the burner setting can be suitably adjusted

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Perform the treated side outside the work area on a test piece, for example on a sample of refractory material to be cleaned and repaired. In this example, the appropriate setting (and hence the appropriate temperature) is determined by observing the melting of the refractory surface.

For design reasons, the head part of the lancet is preferably formed from two parts: an inner block comprising a main bore, fuel and combustion gas channels, and outlet openings of said bore and channels, and an outer block comprising feed lines to the inner block from respective feed lines for particulate material with a carrier gas and for fuel and combustion-promoting gas.

In a preferred embodiment, the inner block of the head portion is positioned and secured by a combination of an internal thread on at least a portion of the outer block and an external thread on at least a portion of the inner block.

Preferably, a profile annular groove is arranged on the outer surface of the inner block so as to form an annular fuel gas distribution chamber in conjunction with the adjacent inner surface of the outer block. Similarly, it is advantageous to arrange the profile annular groove on the outer surface of the inner block so as to form, in conjunction with the adjacent inner surface of the outer block, an annular combustion chamber for the combustion-promoting gas.

The lancet is provided with a lance for suspending the particles in the carrier gas stream, a lance for fuel gas and a lance for combustion-promoting gas. These tubes are preferably surrounded by a protective tube. Protective

78271 (78271a.doc)! The blown pipe is not essential to the invention, but it provides useful protection against mixing gas with water, for example if it leaks due to cracked soldering into the gas supply line. The protective tube ensures the stiffness of the lancet but increases its weight.

For numerous applications, the lancet preferably comprises an outer cooling jacket through which a liquid coolant, such as water, may be passed. The housing typically includes two tubes coaxial to each other and with a lancet, with orifice or apertures between the tubes at the nozzle end, which allow delivery of coolant from the rear end through an annular gap between the lancet and the interior of the jacket tube.

The ceramics welding lances and the embodiments described above do not have specific requirements for powder composition and carrier gas injection rates and are fully applicable to normally used types and volumes of injection materials.

A particular advantage of the method according to the invention is that after applying the flame generated by the combustion of the fuel gas to the surface to be treated to achieve the desired effect, the flame treatment can be stopped and immediately replaced by a particle stream in the carrier gas stream directed to the surface. Due to the use of the flame, the surface of the refractory substrate for repair is completely restored and has the same structure as a new block of the same material. The ceramic welding compound applied immediately thereafter through the main bore is fully compatible with the refractory substrate and its adhesion to the substrate is particularly strong.

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Uprh ^ erláísfťána »· · · · · ·

Overview of the drawings

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of the lancet end region of the present invention (sectional view taken along line BB in FIG. 2); the lancet is of the type suitable for ceramic welding; FIG. 1 is a cross-sectional view of the lancet shown in FIG. 1; FIG.

and 2, the section is taken along line C-C in FIG. 2.

DETAILED DESCRIPTION OF THE INVENTION

The lancet shown has a lance 3 for slurrying ceramic welding powder in a carrier gas stream, a lance 3 for fuel gas, and a lance 3 for oxygen. The protective tube 3 surrounds the tubes 3, 3 and 3. The powder suspension, fuel gas and oxygen are guided in the direction indicated by the central arrow.

The tubes 3, 3, 3 and 3 are connected and terminated on an outer hollow block 10 having a generally conical portion 11 and a generally cylindrical portion 33. The block 10 has internal channels 13, 15 and 16.

which at their inlet end are adapted to connect to the ends of the tubes 3, 3 and 3 and to guide the powder / carrier gas, fuel gas and oxygen through the block 13.

78271 (78271a.doc). .:. .: Modified'page

Inside the outer hollow block 10 is located an inner distributor block 20 which is fixed by complementary threads 14 in both blocks. The block 20 has an axial bore 23 attached to the inlet end of the channel 13 of the block 13. At its downstream end, the bore 23 has internal threads 24 for receiving an optional male threaded tubular insert to reduce the bore 23 to a more suitable size for particular repair work. Said inner end diameter is generally in the range of 1.2 to 2 mm.

The annular groove 25 provided in the outer surface of the block 20, in conjunction with the adjacent inner surface of the block 10, forms an annular fuel gas distribution chamber. The channel 13 extends through the block 10 at an angle to its axis and terminates on its inner surface within said annular manifold chamber.

Similarly, the annular groove 26 provided in the outer surface of the block 20, in conjunction with the adjacent inner surface of the block 10, forms an annular oxygen distribution chamber, the conduit 16 extending through the block 10 at an angle to its axis and terminating on its inner surface.

Branched bores (channels) of 2 mm internal diameter extend from the annular grooves 23 and 23 through the block 20 and protrude through the apertures 29 on the front side thereof. The bores 23 include a long portion extending from the annular groove 26 to the aperture 29 and a short side branch 28a connecting from the annular groove 23. The portion of each bore 28 upstream of the side branch 28 is designated 28b. In the illustrated version there are twelve such branched bores 28 and holes 29.

78271 (78271a.doc) • * * *. .:. .j.UpreveQa-sfoana

In the primary intended use of a ceramic welding repair lancet, fuel gas and oxygen are supplied through pipes 5 and 6. The oxygen passes through the inclined channel 16 into the annular groove 26 and then through the twelve bores 28 and openings 29. The fuel gas passes through the inclined channel 15 into the annular groove 25 and is drawn into the oxygen stream in the bores 28 through the side branches 28a. Thus, the side branches 28a conduct the fuel gas and the portions 28b carry the oxygen, so that the fuel gas and the oxygen do not mix before they reach the connection of the branches 28a and the portions 28b. The flames are formed from the fuel gas / oxygen mixture so formed, emerging from all apertures 29, and joining them to form a purely flame-shaped cleaning flame that moves across the surface to be repaired.

After the desired flame effect on the surface to be repaired has been achieved, the supply of fuel gas and oxygen to the tubes 5 and 6 is stopped. The stream of ceramic welding powder containing the refractory particles and solid fuel particles in the oxygen carrier gas stream is then introduced through the tube 2, the channel 13 and the bore 23 and plunges onto the repair surface where the solid fuel ignites to form a coherent adhering repair mass.

Around the block 20 and the tube 8 is provided a water jacket comprising an outer tube 31 and an inner tube 32. The ends of the tubes 31 and 32 are closed by an annular end plate 33. In operation of the lancet, cooling water is introduced in the direction shown by the two intermediate arrows in FIG. 1 into the annular space between the tubes 22 and 1, then the annular end gap between the tube 31 and the block 10 and then back out of the lancet through the annular gap between the jacket tubes 31 and 22. as indicated by the outer arrows in FIG. 1.

78271 (78271a.doc) • JLrprá ve ná‘strVia

In the test of the apparatus described above, oxygen was fed to the lancet through channels 28 at 4.5 bar and the propane fuel gas was fed through the channels 28 at 2.0 bar. The flame was applied to AZS electric furnace blocks to melt the surface and remove the surface layer, including the surface glass phase. The supply of oxygen and propane was then stopped and immediately thereafter a ceramic welding powder suspended in oxygen as the carrier gas was fed through the bore 23 and cast onto the surface of the refractory. A high-quality, adhering repair compound has been created on the refractory block.

78271 (78271a.doc)

JUDr. Milos Všetečka advocate

120 00 Prague 2, Halkova 2

Claims (17)

»9 9 ♦ · ··· ··· PATENT CLAIMS An apparatus for alternatively flaming or performing a ceramic welding, comprising a single tubular lancet having a nozzle end and a rear end, with a central main bore head portion at the nozzle end, wherein ceramic welding materials comprising particulate material comprising oxidizable particles and a combustion promoting carrier is introduced at the rear end, passing through the main bore and extending in the nozzle, characterized in that the head portion (10 + 20) further comprises at least one channel (28) for conveying a mixture of fuel and combustion gas, each channel (28). has an opening (29) in the lancet nozzle and is provided with a portion (28a) for introducing fuel gas and a portion (28b) for introducing combustion gas, wherein the fuel gas and the combustion gas supplied at the rear end are connected in the channel (28) ) and appear for you forming a flame at the nozzle end of each channel (28), and in that the head portion is formed of two parts, an inner block (20) comprising a main bore (23) and (28) for fuel and combustion gas, and exit ports said bore and channels (29), and an outer block (10) comprising feed passages into the inner block from respective feed lines for particulate material with carrier gas (13), for fuel gas and for combustion-promoting gas (15, 16). Device according to claim 1, characterized in that the main bore (23) coincides substantially with the central axis of the head portion (10 + 20) and around the main bore is A plurality of channels (28) are provided for fuel gas and for combustion-promoting gas (28). Device according to claim 2, characterized in that the channels (28) are evenly distributed around the main bore (23). Apparatus according to claim 2 or 3, characterized in that the channels (28) are sufficient to provide a continuous annular flame. Device according to one of Claims 2 to 4, characterized in that the channels (28) are branched channels, with two supply branches (28a, 28b) connecting to a single output. Device according to one of claims 2 to 5, characterized in that the channels (28) have an inside diameter in the lancet nozzle end in the range of 1.5 to 3.0 mm. Device according to one of the preceding claims, characterized in that the inner block (20) is positioned and fixed by means of a combination of an internal thread on at least a portion of the outer block (10) and an external thread on at least a portion of the inner block (20). Device according to claim 7, characterized in that the profile annular groove (25) on the outer surface of the inner block (20) forms an annular fuel gas distribution chamber in connection with the adjacent inner surface of the outer block (10). Device according to claim 7 or 8, characterized by: 16, wherein the profile annular groove (26) on the outer surface of the inner block forms, in conjunction with the adjacent inner surface of the outer block, an annular combustion gas distribution chamber. Apparatus according to any one of the preceding claims, wherein the lancet comprises a lance for suspending the particles in the carrier gas stream (3), a fuel lance (5) and a combustion lance (6), characterized in that the tubes are surrounded by a protective tube (8). Device according to any one of the preceding claims, characterized in that the lancet comprises an outer cooling jacket (31, 32) through which a liquid refrigerant, for example water, can pass. A method of alternatively flame forming or performing ceramic welding, using a tubular lancet having a nozzle end and a rear end, with a central main bore head portion at the nozzle end, wherein ceramic welding materials comprising particulate material comprising oxidizable particles and a combustion promoting gas are introduced. at the rear end, passing through the main bore and exiting the nozzle, wherein the mixture of fuel gas and combustion-promoting gas is conveyed through at least one channel in the head portion other than the main bore, the head portion further comprising at least one channel having an opening in the nozzle lancets, wherein the fuel gas and the combustion-promoting gas separately supplied at the rear end are combined in the channel and exit to form a flame at the nozzle end of each channel. 16 78271 (78271a.doc) - ¹⁷ -:: ·: dpfóVeriáíštftna ··· ··· ··· · * ·· ·· The method of claim 12, wherein the fuel gas is selected from propane, acetylene, and mixtures of acetylene, such as tetrene ™. The method of claim 12 or 13, wherein the combustion promoting gas is oxygen per se. The method of any one of claims 12 to 14, wherein the fuel gas pressure is about 2.0 to 2.5 bar. The method of claim 12 to 15, wherein the pressure of the combustion promoting gas mixture is about 4.0 to 5.0 bar. Method according to one of Claims 12 to 16, characterized in that the flame produced by the combustion of the fuel gas is first applied to the surface to be treated, then it is stopped by shutting off its gas supply and immediately thereafter a particle stream in the surface is applied. the carrier gas stream.