US2480394A - Punching pipe for converter tuyeres - Google Patents

Description

Aug. 30, 1949.

T. W. CAVERS El' AL PUNcHiNG PIPE' Fon CONVERTER "TUYERES Filed Feb. 7, 1947 Patented Aug. 30, `1949 2,480,394 PUNCHING PIPE FOR CONVERTER TUYRES Thomas Willard Cavers, John Ali'red Cook Franklin, Reginald Clare Mott, and Hugh Fredrick Charles Taylor,

assignors to Falconbrid Toronto, Ontario, Ca

This invention pertains to the construction of tuyres used in converters in which copper and/or nickel matte is converted to a higher grade product such as White metal or blister, and pertains particularly to a novel construction of punching pipes therefor which are means for preventing the obstruction of the said tuyres so that the blast air may pass into the molten metal bath freely and inthe desired volume at all times, thus reducing the time required for the converting operation.

Converters are well known in the art, and' need not be described herein. Generally speaking, a converter is a horizontally disposed cylinder, the length of which is approximately twice its diameter, say for example, 26 ft. long by 13 ft. in diameter, and it is lined throughout with, say 13 inches to 22 inches of refractory brick. At the top of the horizontally disposed cylinder is provided an opening or mouth which, in the foregoing example, might be 6 ft. in diameter; the cylinder is mounted on trunnions so that it may be rotated about a horizontal axis. The matte is poured into the converter through the mouth, and when the converting operation is finished, the converter is rotated on its trunnions so that the material therein may be poured out of the mouth.

When the converter is fully charged with matte and flux (SiOz), the interior thereof is approximately half full. It is of course essential to the operation that blasts of air be blown through the matte at a rate of about 500 cubic ft. per

minute per tuyre. The air is injected into the matte by means of, say 34 to 38 tuyres, which essentially are boiler tubing, approximately 2 inches in diameter set in line horizontally in the, shell of the converter and built into the brick lining thereof. In the particular converter used as an example herein, the distance between the centre line of each tuyre is 6 inches.

In converting matte, the object of the operation being to remove the iron, each blow lasts approximately one hour. During this operation theSiOz is combined with the FeO as it is produced by the oxidation of the iron of the matte, and slag is formed. The tuyres are submerged in the matte bath until the end of the blow, when the converter is tilted on its trunnions, thus carrylng the inner end of the tuyres above the level Falconbridge, Ontario, Canada, ge Nickel Mines Limited,

nada

Application February 7, 1947, Serial No. 727,150 2 Claims. (Cl. 26S-41) of the matte; the air is cut o by the closing of a master main valve.

Slag is lighter than matte and tends to rise to the surface of the bath, but since the slag is produced particularly at the point where thel air is admitted to the bath, i. e. at the tuyre ends, some of it is congealed on the ends of the tuyre pipes thereby forming an obstruction which tends to c ut off the air supply.

The air supply to the tuyres is usually provided by an air manifold connected to a suitable air compressor, the said manifold being secured to the converter somewhat above the level of the bank of tuyres and extending parallel to the side walls of the said converter. At the outer extremity of each tuyre is commonly provided a casting usually known as the tuyre stock," and a short pipe connects the tuyre stock to the air manifold so as to convey the air supply from the latter to the tuyre pipe.

In the prior practice, so as to remove the slag which congeals at the interior end of each tuyre, a solid bar was manually thrust through a Dyblie valve (well known in the art) at the outer end of the tuyre stock, and this bar was pushed through the full length of the tuyre pipe and into the molten bath, thereby breaking off the accretion of congealed slag on the inner end of the tuyre pipe.

Since the punching operation is manually performed, the time intervals between each operation are more or less at the discretion of the workman and therefore the accretions or lfnoses at the end of each tuyre pipe are often so large and solid as to require a blow from a heavy hammer applied at the outer end of the bar,

which procedure is liable to injure the brick lining of the converter. In addition the bar, being solid, reduces the quantity of air passing into the molten bath, thereby slowing down the converting of the matte; moreover, since the bar is introduced through the Dyblie valve on the outer end of the tuyre stock, a substantial quantity of blast air is lost to the atmosphere during the time that the bar is in the tuyre.

It is therefore an object of the present invention to provide a novel tuyre pipe construction in which areincorporated automatic mechanically operated means to remove accretions of 3 slag forming at the inner end of the said tuyre pipe.

It is another object of this invention to provide means for the removal of slag at the inner end of a tuyre pipe, which will in no way nor at any time interfere with the normal now of blast air through the said tuyre pipe.

It is a further object of this invention to provide means for the removal of accretions at the end of the tuyre pipe, the said means which comprise a hollow punching pipe being so constructed that the working end or tip thereof is removable so that it may be easily and simply removed when it has become worn or burned off.

The foregoing and other advantages are achieved by providing a tuyre pipe construction in which is inserted a hollow tubular rod or punching pipe, the outer walls of which are spaced from the inner walls of the tuyre pipe. When the punching pipe is in its normally withdrawn position, its inner end extends to within three or four inches from the inner end of the tuyre pipe. At the outer end of the punching pipe is an extension which projects into a power cylinder and to the said extension is secured a piston operating in the said cylinder. Compressed air, controlled by a suitable valve mechanism, is supplied'at predetermined intervals to the power cylinder alternately on each side of the piston, thereby causing the punching pipe to reciprocate in the tuyre pipe.

The blast air coming from the air manifold is blown in the converter, both through the annular space between the outside periphery of the punching pipe and the inner walls of the tuyre pipe, and through the central portion of the punching pipe; suitable perforations are provided in the walls of the punching pipe to permit the air to enter into the central portion thereof.

Thus the punching pipe disclosed and claimed herein, not only removes the accretions from the end of the tuyres on the bath end thereof, but being hollow and provided with holes for the admission of air, it also carries air into the bath at all times. If a solid bar were used, it would not be practical to leave the solid bar in the tuyre pipe at all times, since it would restrict the flow of air to a considerable extent; if the bar were made of a diameter sufficiently small so as not to appreciably restrict the flow of air, or else if the diameter of the tuyre pipe were enlarged, such a construction would be inoperative, since it could not properly remove the accretions at the inner or bath end of the tuyre pipe unless the end of the said pipe were almost completely blocked. With the punching pipe used in the present invention, the air passes freely to the bath at all times and the speed of converting is increased, since the speed of this operation is a function of the quantity of air admitted in a given time.

The accretions of slag formed on the bath ends of the tuyres are removed before they become large and solid, and thus they are broken up without injury to the expensive magnesite brick lining of the converter. The punching pipe may be operated by the method above indicated, or by any other mechanism that will give the necessary movement. The preferred movement of the punching pipe is a quick power stroke, and a practically instantaneous withdrawal or return stroke, thus preventing as far as possible the burning of the ends thereof. After the punching pipe has been withdrawn back to its normal position, it remains there for an appre- 4 ciable length of time, so that the blast air owing both inside the pipe and in the annular space around it may cool it oil! and thus provide for a longer life.

.All of the foregoing and still further objects and advantages of the invention will become apparent from a study ol the following speeitlcation, taken in conjunction with the accompanying drawings, wherein like characters of reference indicate corresponding parts throughout the several views and wherein:

Fig. 1 is a vertical cross-sectional view of the apparatus, showing a tuyre pipe with its punching pipe, the power device whereby it is operated, and the means for conveying the air to the tuyre pipe;

Fig. 2 is a partial side elevation thereof; and

Fig. 3 is a broken side elevation of a measuring rod adapted for use therewith.

Referring to the drawings, the converter comprises a steel cylinder I lined with refractory brick 2, fragmentary portions only of the cylinder and of the brick being shown in the drawings. Each one of the bricks on the same horizontal row as brick 2a is pierced by a cylindrical opening in which is inserted a tuyre pipe 3. Extending horizontally above and below the row of tuyre pipes are supporting angles 4 and 5, the vertical iianges thereof being suitably secured to the steel cylinder. Secured respectively to the horizontal flanges of the angles 4 and 5 are smaller angles 6 and 1, and the vertical flanges thereof support cover-plate 8 which is provided with openings 9 in order that the tuyre pipes may extend therethrough. The space between the brick and the steel cylinder I and cover-plate 8 is -filled with magnesite or other refractory cement.

A cast iron fitting I0 is secured to the coverplate 8, and the opening therein is recessed at Ia in order to provide a bearing surface for the flared outer end of tuyre pipe 3.

A casting generally indicated at II is secured by bolts Ila to the rear flange of fitting I0, and it will be noted that the front end of the said casting II which is flanged bears against the flared end of tuyre pipe 3 which in turn bears against recessed opening Ina, thus providing a hermetically sealed assembly.

Casting I I is centrally divided by a wall I2, thus dividing it into two halves, namely, the tuyre stock I3 and the power cylinder I4. An extension I5 forms an integral part of the upper wall of the tuyre stock I3 and to it is suitably secured a universally movable connector I6 to which is connected a short length of piping I1 leading from the air manifold I8 (shown broken-away) which conveys the compressed air from any convenient source of supply.

The front wall of the power cylinder is closed by a head I9 at the centre of which is provided a suitable bearing 2U; a similar bearing 2| is provided in wall I2.

Positioned in the tuyre pipe 3 is the punching pipe 25 with attached replaceable tip 26 preferably made of cast iron or 'of some suitable heat resisting alloy. The inner end of tip 26 normally extends to within three or four inches of the tuyre opening when the punching pipe is in the withdrawn position. At the opposite end, the walls of the punching pipe are provided with apertures 21. Threaded into the said oppostie end of punching pipe 25 is a hollow driving shaft 28 which is reciprocably mounted in bearings 20 and 2|, and secured to the said driving shaft is the annular power piston 2l which is reciprocable in power cylinder il.

Compressed air is supplied to the head end of the power cylinder through piplns 3l so as to give it a forward stroke, whereas compressed air is alternately supplied lto the other end of the power cylinder through piping 3| so as to provide a return stroke.

Any suitable control valve mechanism may be used to control the sequence and time oi' the flow of compressed air through pipes 3l and li to the power cylinder. Essentially. manually operated valves in pipes SIb and lib would be sumcient. In practice however, a solenoid actuated valve is preferably used which may be controlled by an electronic timing device which provides a time delay preferably of 45 seconds between each cycle of strokes and which causes the return stroke to occur practically instantaneously after the forward stroke, and also which causes both strokes to be rapid. Since in each converter there are a large number of tuyre pipes, each of which is provided with the apparatus hereinbefore described, it has been found most convenient to operate all the ypunching pipes in synchronism'. Therefore, only one control valve mechanism is required for the whole series of punching pipes. Consequently, pipes 30 and 3| from each power cylinder lead respectively to master pipe lines 30a and Sla which are secured by any suitabe brackets to ansie 5; pipes 30h and lib lead respectively from master pipe lines 30a and lia to the control valve 32. However, when the number of tuyres is large, they may be divided into two or more banks which may be operated by a corresponding number of control valves.

It is clear from the aforementioned description, that although punching pipe 25 is always positioned in tuyre pipe 3, the flow of blast air to the converter does not vary, irrespective of whether the punching pipe is in its normal withdrawn position as shown in full lines in Fig. 1, or is in its advanced position as shown in dotted lines in the said Fig. 1. The blast air flows both through the inner portion of the punching pipe annular piston 2l. the 28 thereof.

The distance between the inner end of a new brick 2a and say the outside of head I9. and the distance between the inner end oi' a new tip 28 and theouter end of hollow driving shaft 28 would of course be known. Thus by inserting measuring rod 34 through the hollow driving shaft,` the annular piston and the punching pipe and engaging the end of tip 28 with bend 38, the extent of the wear of the said tip 28 may be differentially determined. Similarly by engaging the inner end of brick 2a with bend 38, the extent of the wear of the said brick may also be determined. These measurements are taken when the converter is turned down and the tuyres are above the level voi! the bath, or when the converter is empty.

It is thought that the construction and use of the invention will be apparent from the above description of the various parts and their purpose. It is to be understood that the form of the invention herewith shown and described, is to be taken as a preferred example of the same, and that various changes in the shape. size and arrangement of parts may be resorted to, without departing from the spirit of the invention or the scope of the subjoined claims.

What we claim as our invention is:

1. A converter provided with tuyre, means to blast air through the said tuyre, and means to remove accretions forming at inner end of the said tuyre, said means comprising a hollow rod f within said tuyre having an inlet therein to permit the air to enter and flow through the hollow portion thereof, and means for reciprocating the said hollow rod within the tuyre, said means including a power cylinder secured to the converter having bearings at its outer end and at itslinner end which are in alignment with the tuyre, a piston in the said cylinder, a piston rod extending through and reciprocally mountedV in the bearing in the inner end of the cylinder and connected at one end to the hollow rod and at the other end to the piston, another piston rod connected to the piston extending through and and through the annular space between the punching pipe and the tuyre pipe, and consequently the punching pipe is always kept moderately cool and thereby its life is prolonged.

At predetermined time intervals, punching pipe 25 is moved or shot forward quickly by means oi compressed air coming through pipe 30 which forces piston 29 forward. When thepunching pipe has reached its maximum advanced position or soon thereafter (depending on the characteristics of the control valve), the air pressure in pipe 30 is released and thevpressure is transferred to pipe 3 I; consequently, the power piston is returned to its rearward position practically instantaneously.

A closure 33 is threaded into the end of hollow driving lshaft 2B. The object of this removable closure is to provide an easily accessible opening through which may be inserted a suitable rod for determining the extent to which the tip 26 of the punching pipe and the refractory brick 2a adjacent the inner end of the tuyre pipe have become burned or worn out.

The rod is preferably as shown in Fig. 3, and

I it comprises a long handle 35 with a short right angle bend 36 at one end thereof. The bent por'- tion must be suiiiciently short that it may be inreciprocally mounted in the bearing in the outer end of the cylinder, means for the conveyance of a fluid under pressure to the cylinder to cause the said piston and hollow rod to reciprocate, the said hollow rod being spaced from the sides of the tuyre to provide a passage for a portion of the blast air between the outside of the rod and the tuyre, the air passing through and around the hollow rod serving also to cool the said rod.

2. A converter provided with a tuyre, means to blast air through the said tuyre, and means to remove accretions forming at inner end of the said tuyre, said means comprising a hollow rod within said tuyre having an inlet therein to permit the air to enter and flow through the hollow portion thereof, and means for reciprocating the said hollow rod within the tuyre, said means including a power cylinder secured to the converter having bearings at its outer 'end and at its inner end which are in alignment with the tuyre, a piston in the said cylinder, a piston rod extending through and reciprocally mounted in the bearing in the inner end of the cylinder and connected at one end to the hollow rod and at the other end tc serted through the hollow driving shaft 2l, the 7s der pressure to the cylinder to cause the Bald 6 punching pipe 2l and tip 7 piston and hollow rod to reciprocate, a central REFERENCES CITED passageway provided from the hollow rod through The following references are of record m the the piston and piston rod assembly, a closure on the outer end of the second mentioned piston rod, me 0f this patent' y the said closure being openable so as to permit 5 UNITED STATES PATENTS the insertion of a measuring rod or the like i through the piston and piston rod assembly and umher Name Date through the hollow rod 570129 Hartman Oct' 27 1896 616,101 Hartman Dec. 20, 189B THOMAS WILLARD CAVERS 2,244,079 Phllllps June 3, 1941 JOHN ALFRED COOK FRANKLIN. FOREIGN PATENTS REGINALD CLARE MOTT. Number Country Date HUGH FREDRICK CHARLES TAYLOR 261,776 Great Britain June 9, 1927

Images