US3314671A - Apparatus for punching the tuyeres of converters - Google Patents

Description

April 18, 1967 K. H. HEINO ETAL 3,314,671

APPARATUS FOR PUNCHING THE TUYERES OF CONVERTERS Filed Nov. 12, 1963 5 Sheets-Sheet 1 April 18, 1967 K. H. HEINO ET AL 3,314,671-

APPARATUS FOR PUNCHING THE TUYERES OF CONVERTERS,

Filed Nov. 12, 1963 5 Sheets-Sheet z H cu FIG. 2

April 18, 1967 K. H. HEINO ET AL 3,314,671

APPARATUS FOR PUNCHING THE TUYERES OF CONVERTERS Filed Nov 12, 1963 5 Sheets-Sheet 5 FIG. 3

A ril 18, 1967 APPARATUS FOR FUNCHING THE TUYERES OF CONVERTERS Filed Nov. 12, 1963 5 Sheets-Sheet 4 K, H. HEINO ET AL 3,314,671

April 18, 1967 K. H. HEINO ET AL 3,314,671

APPARATUS FOR PUNCHING THE TUYERES OF CONVERTERS Filed Nov. 12, 1963 5 Sheets-Sheet 5 FIG. 5

United States Patent Ofitice 3314,71 Patented Apr. 18, 1967 3,314,671 APPARATUS FOR PUNCHING THE TUYERES F CONVERTERS Kauko Henry Heino, Peter Leslie Fowler, and Albert Pelletier, Murdochville, Quebec, Canada, assignors to Gaspe Copper Mines, Limited, Toronto, Ontario,

Canada Filed Nov. 12, 1963, Ser. No. 322,764

Claims priority, application Canada, Sept. 10, 1963,

6 Claims. (Cl.

This invention relates generally to apparatus for punching the tuyeres of converters which are employed in smelting operations.

In the smelting of certain metals it is common practice to remove some of the impurities present by treatment of the molten metal in a converter by means of air forced into the melt. The air may be forced into the molten metal by way of a number of openings in the converter shell, called tuyeres whose positions are predetermined and which are submerged under the metal being treated.

During this operation, commonly called a blowing operation, it is necessary to punch the tuyeres frequently to remove the undesirable slag, otherwise encrustations solidify at the inner ends of the tuyere openings. If they are not removed these encrustations impede and eventually shut off the flow of air through the tuyeres. In this event the operation of the converter is impaired or nullified. It is therefore important for efiicient operation of the converter to maintain a maximum flow of air into the melt.

It was, and in some instances still is, common practice to remove the formed encrustations manually by inserting a bar into the outer end of the tuyere and pushing it against the encrustations to break them away. However, it should be noted that several machines were previously designed with a view to automatically and continuously performing the punching operation. Some of the earlier machines are disclosed in United States Patents 1,219,963; 2,425,792; and 2,432,996, but none of these developments proved entirely satisfactory :for various reasons from both operation and economic points of view.

It may be noted here that this invention has particular application in the removal of iron and sulfur impurities from copper to produce what is known in the art as blister copper.

It is known that converter punchers comprise generally at least two main types; those mounted directly on the converter shell itself and those mounted independently of the converter.

Shell mounted punchers have a number of disadvantages. Their design and construction is costly since a structural framework supporting the puncher on the converter must be provided. This necessitates a specially designed and strengthened converter body to serve as a mounting for the punchers. The tuyere openings are usually very close together (a centre to centre distance of six inches not being uncommon) and the converter must be free to rotate. This requires that the mechanical punchers do not protrude far from the converter shell. Due to the closeness of the individual tuyere openings and the lack of protrusion required the mechanical components must therefore be small and compact. Accordingly machining tolerances are closer, component parts are smaller and weaker, and maintenance difiicult.

Shell mounted punching devices which are movable and can punch a plurality of tuyeres separately have proved impractical due to the above limitations of space and support. The shell mounted punchers which are in use are similar to that disclosed in United States Patent No. 2,432,996 and require a separate and distinct mechanism for each tuyere. Since many converters contain as many as fifty to sixty tuyeres, a very high initial cost is required to equip each tuyere with its separate punching mechanism.

A number of additional disadvantages are present in tuyere punchers mounted on the converter shell. For example, since the puncher is attached to the converter shell it must roll with the shell when the converter is turned down out of the stack for slag skimming. This places the puncher under the exhaust gas hood when the converter is turned down and the punching mechanism must be protected by special devices against the effects of heat and falling agglomerations.

Additionally in a number of situations it is very desirable to move the mechanical puncher out of the way to provide access to the tuyere opening. With the use of earlier developments the heads on the punch rods are smaller in diameter than the inside diameter of the tuyere pipe. As a result a rod with a bigger head must be driven through the tuyere a number of times each day in order to restore the full opening of the tuyere. To accomplish this it is necessary to remove each individual puncher mechanism from the converter shell. Also, in the production of blister copper, just before the converter blowing cycle is completed the melt in the converter contains a high percentage of blister copper. This copper tends to adhere and solidify onto the punch bars when they are inserted into the bath much more readily and the diameter of the bar becomes so large that it often sticks in the tuyere pipe. The shell mounted puncher must be dismounted from the shell and from its com pressed air supply before it can be removed and another punch rod substituted or the tuyere punched by hand. Also, in some of the prior art devices, since it is not unusual for a large percentage of the punch rods to stick towards the end of the converter cycle, and there would not be time available to remove all the mechanical punchers so that hand punching could be utilized, it is common practice to remove one third or more of the punchers from the converter in advance so that these tuyeres may be punched by hand. Such practices as this in the use of the prior art are both tedious and uneconomical.

The present invention provides a tuyere punching apparatus which is mounted independently of the converter itself and which has, among other things, embodied within its construction several aspects and features which make it superior to the earlier developments and which are desirable in apparatus of this type. These features include:

(1) No part of the invention is directly connected to the converter. This feature permits turning and tilting of the converter without having the punching mechanism interfere with the converter or stack supports.

(2) Since the punching mechanism is mounted independently of the converter, motion of the converter will vertically align the punching tool with the tuyeres when the converter returns to the blowing position after the skimming or emptying of the metal into ladles.

(3) Provision is also made to ensure that the puncher can still function despite small vertical or horizontal misalignments. These misalignments can be caused by the operator failing to place the punching device or the converter exactly in line or because of distortions of the converter shell or brickwork caused by heat which occur in practically every converter after a short period of use.

(4) It is of some importance in apparatus of this type to provide eflicient and reliable means for pushing the punch rods into the tuyere pipes and thereafter retrieving them. Such means are provided in this invention.

(5) Means to guide each punch rod in its forward and return travel is included in the structure of the invention.

(6) Some method should be provided for terminating the inward stroke and starting the return stroke when the head of the punch rod has penetrated to the required distance. The change from the in-stroke to the out-stroke must be virtually instantaneous so that there is a minimum of opportunity for molten slag, matte, or metal to freeze and adhere to the rod. At the same time the length of stroke must be capable of being varied so that it may be shortened as the tuyere pipe length shortens during the life of the converter brickwork.

(7) The build up of material which the puncher is required to remove is at the end of tuyere pipe closest to the molten metal. In consequence the return stroke meets little resistance after the first few inches. The provision of some means is preferred which will bring the assembly to a stop slowly, thus preventing excessive jarring of the mechanism.

(8) As mentioned earlier, near the end of the converter cycle in the production of blister copper in its finished form, the copper tends to freeze onto or adhere to the relatively cold punch rod which causes it to stick in the tuyere pipe. It is therefore preferable that some means be provided for heating the punching rod during this portion of the blowing cycle to minimize the amount of copper which does solidify onto the rod end.

(9) To achieve economy of construction and operation it has been found desirable to mount the mechanical puncher so that it can be moved horizontally beside the converter. In this manner one puncher can be used to serve different groups of tuyeres but a track must be provided for the puncher which will guide the puncher during its travel. Both manual and power driven means may be provided for moving and stopping the mechanism in alignment with the tuyeres to be punched and for effecting the punching stroke. In some applications it may be practical and desirable for the driven means to operate the puncher automatically. Provision should also be made for some means which may be used for moving the machine aside to permit manual punching of the tuyere, should an emergency arise.

(10) It might occur that either by design or accident the converter is turned on its axis while the punch rods are still within the tuyeres. If there is a cessation of the air flow supplied to the converter tuyeres it is common practice to have an automatic device which will turn the converter so that the tuyere pipes will rise above the level of the melt. If: this is not done the tuyeres fill with molten metal. As a result means should be provided which will allow the converter to rotate when the punch rods are in the tuyeres without wrecking the machine.

None of the known prior art devices has successfully overcome all the above problems satisfactorily while at the same time providing tuyere punching apparatus which is practical and economical from both initial cost and maintenance points of view. A particular example of the prior art is the provision in the p uncher disclosed by Forbes US. Patent 2,425,792 of interlocking controls between the converter rotating apparatus and the tuyere puncher so that if a punch rod is in the tuyere the converter cannot be turned over. If a punch rod sticks and an air failure occurs in the Forbes apparatus, either the machine has to be Wrecked or the tuyeres are allowed to fill with molten metal. Also in the Forbes patent the feature of adjustability outlined in (6) above is accomplished by the use of two separate cylinders mounted one above the other. This structure increases the initial and maintenance costs and the device is difficult and cumbersome to operate.

It is therefore an object of this invention to fill the need for an improved apparatus for punching the tuyeres of converters.

Although the objects and characteristics of the invention have been detailed hereinbefore the invention in its broad aspects and broad concept can be stated as an apparatus adapted for punching the tuyeres of a converter comprising a frame mounted independent from and movable relative to said converter, punching mechanism supported by said frame and including at least one punch rod; said punching mechanism having means for pushing a punch rod into and withdrawing same from a selected tuyere, said rod being removably mounted in a manner that it may be quickly detached from said apparatus, means for guiding said rod during movement, and means for controlling the inward and return stroke of said punching mechanism.

One embodiment of the invention will now be described with reference to the accompanying drawings in which:

FIG. 1 is a perspective view of the punching apparatus in position beside the converter and with the punch rods inserted into the tuyeres;

FIG. 2 is a side elevation of the punching apparatus;

FIG. 3 is a plan view of the punching apparatus shown in FIG. 2;

FIG. 4 is an end view of the punching apparatus viewed from the left as shown in FIG. 2; and

FIG. 5 is an end view of the punching apparatus viewed from the right as shown in FIG. 2.

Referring to FIG. 1, a cylindrical converter mounted for rotation about its longitudinal axis is shown at 4. This converter has tuyere openings 25 formed therein which are supplied with air by means of pipes 8.

Beside the converter are two rails 1 which are rigidly secured by means of base plates 2, to the base area on the side of the converter which faces the tuyere openings. The rails 1 are parallel to each other and to the longitudinal axis of the converter and may be of any shape and track gauge desired to provide the proper support and guidance for the punching apparatus. Wheels 3 are mounted for rotation on axle shafts 6 and are spaced and shaped to run along and remain supported by rails 1. Axle shafts 6 are rigidly connected by and support carriage frame 7. In the preferred embodiment shown, four wheels, mounted on two axles are shown, but any number of Wheels or axles which is practical or desired may be utilized. The frame 7 provides a base upon which the actual punching mechanism is mounted.

Counterweights 27 are mounted on the frame 7 on the side which is closest to the converter so that the wheels 3 will not rise off the rail 1. On the side remote from the converter a hold down rail 28 is provided above the rail 1. The rail 28 is supported on the base plates 2 directly above the rail 1, and is maintained by a rigid framework at such a height relative to rail 1 that wheels 3 can pass freely along rail 1 without touching the hold down rail. The hold down rail, which is just above the wheels, prevents the end of the carriage remote from the converter from lifting off the rail at any time during the punching cycle. The use of weights and hold down rails is not essential to the operation of the apparatus and may be omitted, if desired, without departing from the scope of the invention.

A standard industrial air cylinder 9 complete with piston and shaft is mounted on frame 7 with its longitudinal axis perpendicular to the rails 1 so that it is aligned with the longitudinal axis of the tuyere pipes when the converter is turned in its preferred punching position. Fastened to the end of the piston shaft remote from the cylinder is a crosshead or yoke 21. A plurality of punch rod holders 23, one for each punch rod 5, are fastened to the face of the yoke towards the converter and are disposed across the length of the yoke so that there are an equal number on each side of the piston shaft connection. In the embodiment illustrated, four punch rods 5 are shown connected to the yoke 21, but it should be understood that as few as 1 and more than 4 punch rods may be utilized. It will also be apparent to those skilled in the art that any fluid operated cylinder may be used in place of air cylinder 9 and that a plurality of cylinders could be mounted on the same frame, each cylinder and piston operating its own set of punch rods, or an electrically driven shaft might be used.

is adapted to be turned The yoke 21 is equipped with one or more guide blocks 17 which run in guides 24. Guides 24 are fastened securely to frame 7 and are set parallel to the longitudinal axis of cylinder 9. These guides and blocks restrain the yoke so that it travels in the longitudinal direction of the cylinder only and guides the punch rods 5.

In the particular embodiment the punch rods 5 are made of steel and the prime consideration is that they be thick enough to withstand the thrust applied by the cylinder and they they are not too thick for use within the tuyere pipes. The punching end of the rod 5, the end which enters the tuyeres, is usually slightly expanded to form a head as shown in the drawings. A short length at one end of each rod is bent at a right angle to the main portion and fits into punch rod holder 23.

Each punch rod holder 23 consists of a vertically disposed steel hollow cylinder with one side flattened for attachment to the yoke. A bushing of hardened steel is fastened inside the cylinder which provides a vertical hole through the length of the bushing of sufiicient diameter to provide a free running fit with the end of each punch rod 5.

Punch rods 5 pass through vertical slots 16 in a punch rod guide plate 22, which is secured to the frame 7, and through guides 24. The guide plate 22 is verticaily adjustable for alignment with the tuyeres.

Mounted adjacent hold down rail 28 and supported on base plates 2 is a spur rack 10. Spur gear 15 is'mounted on carriage frame 7 in engagement with rack 10 and by wheel 11. In the embodiment illustrated in the drawings, the wheel 11 is equipped with a handle 12 so that it may be turned by hand but it is clear that some other means, such as motor could be utilized to rotate gear 15. Turning of gear 15 in engagement with rack 10 propels the punching device along the rails 1 and positions it at the desired spot relative to the converter. It falls within the scope of the invention to utilize alternative means other than the spur rack and gear to propel the punching apparatus. Such an alternative could be a rotative force applied to the axle shaft of the supporting wheels 3, or the apparatus could even be pushed by hand.

In operation the punch rods 5 pass freely back and forth through slots 16 in guide plate 22, which is vertically adjustable. As stated previously, the end portion of each punch rod is bent at a right angle to the main portion and is inserted in a vertical hole in punch rod holder 23 in a free manner. In this way, should the converter be turned on axis While the rods are still inside the tuyeres or should the converter tuyeres be seriously out of vertical alignment with path of travel of the rods, the rods are free to lift out of the rod holders 23 and rod guide slots 16 and thus become completely free of the remainder of the punching mechanism. Additionally the removal of a punch rod is accomplished easily to lift it from the machine. Although one method has been disclosed of mounting the punch rods 5 so that they are readily removable and detach themselves from the apparatus should the converter rotate, it will be apparent to those skilled in the art on the basis of this teaching that alternative ways of removably mounting the rods can be utilized.

The converter is normally arranged to be turned on its longitudinal axis and vertical alignment of the punch rods and tuyere openings may be accomplished by the placing of a marker or other device so that the converter can be arrested at the required spot. Horizontal alignment can be achieved by means of spur rack 10 and gear 11.

Small misalignments between the punch rod and tuyeres may occur both through the error of the operator and through vertical and horizontal displacement of the tuyere pipe caused by heat distortion of the brick lining of the converter shell. These small misalignments may be allowed for by machining the tuyere opening 25 so that .to the return stroke so that it is funnel-shaped. The slope of the funneled sides will then guide the punch rod 5 into the tuyere tube.

In operation the piston in cylinder 9 is driven in the normal manner by any suitable fluid such as compressed air. The compressed air flow is controlled by a standard solenoid operated control valve, shown at 20. This valve is wired to permit the air to flow so that it will force the air cylinder to drive the punch rod into the converter when the switch 26 is pressed. The yoke 21 is equipped with a limit switch actuator shown at 18 which, when the yoke has reached the termination point for the desired penetration of the punch rods, moves the arm of limit switch 19. The actuation of limit switch 19 reverses the solenoid valve 20 causing the cylinder to operate in the reverse direction and withdraw the punch rods. The actuator 18 is rigidly fastened to the yoke 21 while the limit switch 19 is adjustably mounted to frame 7 in such a manner that its position relative to the cylinder may be changed, thus providing an easy manner in which to adjust the length of the piston stroke and thus the depth of punch rod penetration. The use of the limit switch also permits instantaneous reversal from the inward stroke there is a minimum opportunity for molten slag or metal to solidify and adhere to the rod.

An additional feature, which is not shown in the drawings but may usefully be added if desired, is a second limit switch and actuator. Such a switch would be mounted to be actuated on the return stroke of the piston and connected to a solenoid valve which would cut off thecompressed air to the cylinder in time to slow the piston before it reached its stopped position. This would prevent the piston or yoke from hammering into the cylinder assembly as it comes to rest. Cushioning material could also be provided between the yoke 21 and the cylinder 9.

In addition to limit switch 19 an override switch may be provided which short circuits the action of the limit switch so that the punch rods may be held immersed in the melt t0 the full length of the rod and held there as long as is desired. This method is used to heat the rods when punching towards the end of the blowing cycle when there is a high percentage of copper present, as described in (8) above.

Although the apparatus as disclosed above is designed primarily for manual operation it is conceivable and within the scope of the invention that the puncher could be set up for partial or complete automatic operation. Also, although only one puncher has ben shown, a plurality of punchers could be provided on the same or separate rails, if desired.

The practical and economical advantages achieved in the operation of the present invention have already been recognized by skilled men in the held and it is considered to represent a distinct advance in the art.

We claim:

1. Apparatus adapted for punching the tuyeres of a converter comprising a frame mounted independent from and movable relative to said converter; a punching mechanism supported by said frame and including at least one punch rod freely mounted in said punching mechanism such that an upward urging of the rod will lift the rod free of said punching mechanism, and means for pushing said punch rod into and withdrawing same from a selected tuyere; means for guiding said rod during movemeans for controlling the inward and return stroke of said punching mechanism.

2. Apparaus adapted for punching the tuyeres of a converter comprising a frame mounted independent from and movable relative to said converter; a punching mechanism supported by said frame and including at least one punch rod removably mounted on said mechanism in a manner that it may be quickly detached from said apparatus, said punching mechanism having means for pushing said puch rod into and withdrawing the same from a selected tuyere; means for guiding said rod during movement; a limit switch for controlling the inward and return stroke of said punching mechanism; means to actuate said limit switch when said punch rod has penetrated to the desired depth to reverse the operation of said punching mechanism and withdraw the punch rod; and an override switch operable to short circuit the action of said limit switch.

3. Apparatus as defined in claim 2 in which said limit switch is adjustable to vary the depth of punch rod penetration.

4. Apparatus adapted for punching the tuyeres of a converter comprising a frame mounted independent from and movable relative to said converter; a punching mechanism supported by said frame and including at least one punch rod, a punch rod holder, the end of said punch rod remote from the end which enters the converter tuyere being bent at a right angle to the main portion of the punch rod and being inserted freely in a vertical hole provided by said punch rod holder, and a fluid operated cylinder for pushing said punch rod into and withdrawing same from a selected tuyere, said cylinder having a piston assembly including a shaft adapted to be connected to the punch rod; means for guiding said rod during movement; and means for controlling the inward and return stroke of said punching mechanism.

5. Apparatus as defined in claim 4 in which said shaft is provided at the end thereof remote from the piston with a yoke adapted to receive a plurality of punch rods.

6. Apparatus adapted for punching the tuyeres of a converter comprising a frame mounted independent from and movable relative to said converter; a punching mechanism supported by said frame and including at least one punch rod freely mounted in said punching mechanism such that an upward urging of the rod Will lift the rod free of said punching mechanism, and means for pushing said punch rod into and withdrawing same from a selected tuyere; means for guiding said rod during movement; means for controlling the inward and return stroke of said punching mechanism; a supporting structure for said frame adapted to guide and maintain same in substantially parallel relationship to said converter; and a counterweight and anchoring assembly for inhibiting the lifting of said frame from its supporting structure.

References Cited by the Examiner UNITED STATES PATENTS 949,576 2/1910 Hunter 24868 1,219,963 3/1917 Lefebvre 266--42 1,303,755 5/1919 Arch 266-42 1,665,389 4/1928 Willoughby 287-20.5 1,999,640 4/1935 =Royse 266-42 2,425,792 8/1947 Forbes 266-42 2,432,996 12/1947 Larsen et al. 266-42 JOHN F. CAMPBELL, Primary Examiner. L. I. WESTFALL, Assistant Examiner.

Claims (1)

1. APPARATUS ADAPTED FOR PUNCHING THE TUYERES OF A CONVERTER COMPRISING A FRAME MOUNTED INDEPENDENT FROM AND MOVABLE RELATIVE TO SAID CONVERTER; A PUNCHING MECHANISM SUPPORTED BY SAID FRAME AND INCLUDING AT LEAST ONE PUNCH ROD FREELY MOUNTED IN SAID PUNCHING MECHANISM SUCH THAT AN UPWARD URGING OF THE ROD WILL LIFT THE ROD FREE OF SAID PUNCHING MECHANISM, AND MEANS FOR PUSHING SAID PUNCH ROD INTO AND WITHDRAWING SAME FROM A SELECTED TUYERE; MEANS FOR GUIDING SAID ROD DURING MOVEMENT; AND MEANS FOR CONTROLLING THE INWARD AND RETURN STROKE OF SAID PUNCHING MECHANISM.

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