US3314550A

US3314550A - Furnace charger crane

Info

Publication number: US3314550A
Application number: US473755A
Authority: US
Inventors: Ross B Mccready; Klaus W Forster
Original assignee: Kerma Corp
Current assignee: Kerma Corp
Priority date: 1965-07-21
Filing date: 1965-07-21
Publication date: 1967-04-18
Anticipated expiration: 1984-04-18

Description

April 18, 1967 B MCCREADY ET AL 3,314,550

FURNACE CHARGER CRANE Filed July 21, 1965 3 Sheets-$heet.1

INVENTORS ROSS B. M CREADY KL AUS W. P025752 ATTORNEYS April 18, 1967 MCCREADY ET AL FURNACE CHARGER CRANE 5 Sheets-Sheet 2 Filed July 21 mvmroxs R088 8. MCREADY ALAus mFoesrflz ATTORNEYS April 18, 1967 R. B. M CREADY ET AL 3,314,550

FURNACE CHARGER CRANE Filed July 21, 1965 3 Sheets-Sheet 5 INVENTORS R088 8. MCR'ADY 4w ATTORNEYS United States Patent C) 3,314,550 FURNACE CHARGER CRANE Ross B. McCready, Alliance, and Klaus W. Forster,

Brecksville, Ohio, assignors to Kerma Corporation, Alliance, Ohio, a corporation of Ohio Filed July 21, 1965, Ser. No. 473,755 11 Claims. (Cl. 212-130) The present invention relates to overhead traveling cranes and more particularly to overhead traveling cranes designed for use in the charging of basic oxygen furnace vessels and the like.

Two steps involved in the charging of basic oxygen furnaces are the addition of molten metal and the addi tion of scrap metal to the vessel. At present it is customary to employ one of two methods to charge the furnace vessels, a floor mounted charger or a twin hoist overhead crane charger. The great amount of space required by the floor mounted charger has added to the increased use by the steel industry of the overhead crane charger. The present invention is an improvement in the design of the twin hoist overhead charger and provides performance superior to the overhead chargers which are being used by the industry at the present time.

When a twin hoist overhead crane is employed in the transport of scrap metal in a scrap box to the furnace vessel the movement of the crane incidental to the transport causes the scrap box to swing which prevents rapid and ready alignment of the box with the furnace vessel. In dumping the scrap box, the shift of the weight of the load in the scrap box further causes undesired swinging of the box.

One of the principal objects of the present invention is the provision of a new and improved overhead crane designed to provide for quick transportation of scrap boxes to basic oxygen furnace vessels and the like, rapid alignment of the scrap box and the furnace vessel, and firm support of the scrap box during dumping.

Another object of the present invention is the provision of a twin hoist overhead traveling crane provided with structure supported thereby which engages the transported load as it is hoisted to the raised position preventing lateral movement of the load during maneuvering of the crane to bring the load to a predetermined position and during the dumping of the transported load.

Another object of the present invention is the provision of a twin hoist overhead traveling crane designed in such a manner that it may be used either for the transport of a molten metal ladle or a scrap metal box.

Another object of the present invention is the provision of a twin hoist overhead traveling crane and a scrap box of novel design which cooperate to provide quick transportation of the scrap box to the furnace vessel, rapid alignment of the scrap box and the furnace vessel and stable support of the scrap box during dumping.

Another object of the present invention is the provision of grab means adapted to detachably engage one of two members rotatable to one another about a transverse axis at a point spaced from the axis about which the members rotate relative to one another and limit rotation of the engaged member relative to the grab means.

Another object of the present invention is the provision of a scrap box or the like comprising two members rotatable relative to one another, one of which is a boxlike container and the other of which has trunnion means for engagement by a grab.

The invention resides in certain constructions and arrangements of parts and further objects and advantages of the invention will be apparent from the following description of the preferred embodiment described with references to the accompanying drawings forming a part 3,3l4,55@ Patented Apr. 18, 1%67 of this specification in which similar reference characters designate corresponding parts, and in which FIG. 1 is a fragmentary side elevational view with parts broken away of a two crane installation embodying the present invention for dumping molten metal and scrap metal into a basic oxygen furnace, the vessel of which is shown in phantom lines;

FIG. 2 is a fragmentary view with parts broken away of the crane designed to handle the scrap boxes with the scrap box in position to be dumped into the furnace vessel;

FIG. 3 is a sectional view approximately on the line 3-3 of the crane shown in FIG. 2 with parts broken away;

FIG. 4 is a sectional view approximately on the line 4-4 of FIG. 2;

FIG. 5 is a fragmentary side elevational View similar to the lower left-"hand part of FIG. 1, but showing a modified construction, and

FIG. 6 is a fragmentary view similar to the lower part of FIG. 2, but showing the modified construction of FIGURE 5.

Referring to the drawings, the installation illustrated comprises two overhead traveling bridge-type cranes A, B adapted for charging the vessel C, shown in phantom lines, of a basic oxygen furnace with molten metal and scrap metal. The furnace and cranes are located in a building, not shown, and the bridges D, E of the crane A, B, respectively, are supported on and travel from one location in the building to another along the same runway comprising widely separated rails, only one of which appears in the drawings. The crane runway rails are supported by suitable elevated structures. according to well-known practices. The bridge D of the crane A comprises two beam members 10, 11 connected to end trucks supported by flanged wheels on the rails of the crane runway. The bridge is moved along the crane runway by driving mechanisms of conventional construction controlled by an operator riding in a cab on the crane, which cab, for the sake of simplicity, is not shown. The crane A thus far described including the drive mentioned may be of any suitable conventional construction, such as the bridge type crane described in United States Patent No. 3,095,829.

In addition to the bridge D, the crane A comprises a trolley P which rides on rails supported on the top of the bridge beams 10 and 11, respectively, and driven by suitable power means, also under the control of the crane operator, so that the trolley can be caused to move from one end of the bridge to the other. The trolley F shown is similar with the trolley shown in United States Patent No. 3,111,228 and includes a frame which supports or carries two hoisting mechanisms, one designated generally as G constitutes the principal load lifting mechanism, which load in the embodiment shown is a ladle H and the other designated generally as K constitutes the dumping mechanism for tilting and dumping the load or ladle. The load lift hoist mechanism G shown has two sets of hoisting cables connected to a single cable drum mechanism extending transversely of the length of the crane bridge and driven by an electric motor, controlled by the crane operator, to raise or lower a load grab L comprising a cross beam or spreader structure having sheaves journaled in the ends thereof about which the hoist cables are reeved, and a pair of hooks attached to opposite ends of the spreader and depend therefrom for pivotally engaging trunnions on the load or ladle H to be hoisted.

The load tilting hoist mechanism K comprises a hoisting cable having its opposite ends connected to a cable drum driven by an electric motor cont-rolled by the crane operator. The cable is reeved about a pair of sheaves connected to a hook-like grab 16 and the center loop of the cable passes over a sheave connected to a frame supported in the crane trolley for movement toward and from the main hoist cable drum so that the pull on the grab can be maintained substantially vertical during the dumping of the load, which in the present instance is the ladle H. It being understood that the grab 16 is connected to the ladle tilt bracket connected to the ladle adjacent to its bottom at the side opposite its pouring lip. As previously mentioned, the trolley F illustrated is, in construction and operation, like that shown and described in United States Patent No. 3,111,228. It is to be understood, however, that other trolley arrangements may be employed, for example, that shown in United States Patent No. 1,430,009.

The crane B illustrated including its trolley M, which travels on the bridge B comprising the beams or

girders

20 and 21, is similar in construction and operation to the crane A except that the trolley is longer in the direction of its travel on the bridge so as to space the load lift hoist and the load tilting hoist mechanisms N and P, respectively, farther apart because the load to be handled, that is, the scrap box S is longer lengthwise of the bridge than the ladle L. It is to be understood, however, that the scrap box may be shorter or in fact longer than the box S shown, as desired. The lengthening of the trolley M is preferably accomplished in such a manner that the movable member which carries the sheave about which the center loop of the tilt cable 23, to which the tilt grab 24 is attached, is reeved can move proportionately farther than the corresponding member of the trolley F, The only other differences between the trolleys F and M are the

books

25 and 26 of the load grab R suspended by the cables 27 and 28 of the load hoist mechanism N and the inclusion in the trolley M of means for receiving the load lift grab R and holding it and the scrap box against lateral movement when the load has been raised to a predetermined position, which position in the present instance, is that required for dumping the scrap in the scrap box into the furnace vessel.

As previously mentioned in the operation of a furnace of the character referred to, molten metal and scrap metal are periodically dumped into the top opening of the furnace vessel and in the arrangements disclosed, crane A is used to transport the molten metal in a conventional ladle H from some point in the building to the furnace and dump the metal in the vessel of the furnace. For this purpose the trunnions of the ladle are engaged in the hooks of the load hoist mechanism grab L and the tilt bracket on the ladle engaged by the grab 16. Both hoist mechanisms are operated to raise the ladle to the desired elevation after which the ladle is tilted about the axis of its trunnions by operating the tilt hoist mechanism K to raise the grab 16 thereof to dump the metal into the furnace opening.

The crane B is employed to transfer the scrap boxes S to the furnace and dump the scrap metal therein into the furnace. A number of boxes may be loaded with scrap metal in one or more locations in the building and transported one at a time by crane B to the furnace and the scrap therein dumped into the furnace. The scrap box S is a rectangular trough-like box 30 having one end closed and the other end provided with a discharge chute 31 for guiding or directing the scrap metal out of the end of the box as the box is tilted.

Referring particularly to the preferred embodiment shown in FIGS. 1 to 4, the scrap boxes S include a cradle or U-shaped bracket T comprising

side members

36 and 37 at opposite sides of the box proper and connects one another by a bottom member 38 extending underneath the box near but spaced from its dumping end. The side members project to the forward or dumping end of the box and are pivotally connected to opposite sides of the box adjacent its forward end by trunnions 40 and 41 on opposite sides of the box which engage in suitable apertures in the

side members

36 and 37, respectively.

The upper ends of the

side members

36, 37 are provided with outwardly extending

trunnions

42, 43 which are adapted to be engaged in apertures 44 and 45 of the

hooks

25, 26, respectively, of the load grab R. The

hooks

25 and 26 have

portions

46, 47, respectively, extending below the apertures 44 and 45 and which extensions are provided with bearing surfaces 50 and 51 adapted to engage

members

52 and 53, respectively, forming a part of and projecting outwardly from the main portions of the

side members

36, 37, respectively. Portions of the hook on the right-hand side, as viewed in FIGS. 1 and 2 of the drawings, that is, the side opposite to the side in which the apertures 44 and 45 open, are provided with bearing surfaces 54 and 55, respectively, the purpose of which will be hereinafter apparent.

When a scrap box is handled by a crane, such as the crane A shown, as previously stated, the acceleration and deceleration of the bridge and trolley in moving the box to the furnace cause the suspended box to swing which prevents ready alignment of the discharge chute of the box with the furnace opening, and after a box has been aligned with the furnace, the tilting of the box and the movement of the scrap from the box shifts the weight suspended by the cables all of which tends to and usually does, swing the box out of its aligned position with the furnace. To overcome these diificulties, the trolley M of the crane A is provided with a guide structure V projecting downwardly therebelow which receives the ends of the spreader and the upper portions of the

hooks

25 and 26 when the grab R is raised a predetermined distance and prevents lateral movements of the hooks and, in turn, the suspended scrap box. When the grab is in its elevated position with the hook engaged in the guide structure, as illustrated in FIG. 2, the scrap box moves exactly in accordance with the movements of the bridge and/or trolley and the crane operator may quickly align the discharge chute of the box with the furnace opening, and the alignment will be maintained throughout the scrap dumping operation.

Guide structure V shown comprises two members 69, 61, preferably weldments, welded or otherwise secured to and projecting downwardly from the trolley frame adjacent to opposite sides thereof. In the embodiment shown both upper ends of the members 60 and 61, as viewed in FIG. 1, are connected by

integral webs

62, 63 and 64 for stability purposes. The guide members 60 and 61 comprise inwardly facing vertical grooves or

channels

65 and 66, respectively, extending to their lower ends adapted to receive the ends of the spreader structure and the upper portions of the

hooks

25 and 26. The guide members confine the ends of the grab including the

hooks

25 and 26 when the grab is raised to engage within the

channels

65, 66 and prevent movement thereof and the scrap box S relative to the trolley in all directions except vertically. Preferably, the lower portions of the openings or

channels

65 and 66 in the guide members are bevelled to facilitate entry of the grab thereinto.

The

hooks

25 and 26 extend below the trolley guide structure and the point about which the scrap box pivots in dumping its contents into the furnace vessel, that is, the axes of the aligned trunnions 40 and 41 on the box, is located below and to the furnace side of the trolley. The advantages of this construction are believed to be apparent.

While in the preferred embodiment a spreader type grab is employed with the principal hoist mechanisms it is to be understood that the spreader could be eliminated and the hooks of the grab directly attached to the pulley blocks on the lower end of the cables and the cables rearranged .on the main hoist drum so that the hooks would enter the channels in the guide structure and be restrained thereby against lateral shifting.

When the right-hand end of the scrap box S is raised to the position shown in FIG. 2 by actuation of the hoist mechanism P, the box S pivots above its trunnions 40 and 41 which are confined in the

side members

36, 37, respectively, of the bracket T. The bracket is prevented from moving toward the right by the engagement of

members

52 and 53 against the lower bearing surfaces 50 and 51 on the

hooks

25 and 26 and the upper bearing surfaces 54 and 55 on the

hooks

25 and 26 against the right-hand sides of the

channels

65 and 66, respectively. In the embodiment shown the ends of the spreader of the grab R and the upper ends of the

hooks

25 and 26 are also confined in the

channels

65 and 66 by the engagement of the ends of the spreader against the left-hand sides of the channels. The bracket T is prevented from swinging counterclockwise about the

trunnions

42 and 43 by the engagement of the

members

52 and 53 against the bear ing surfaces 50 and 51 on the

lower end portions

46 and 47 of the

hooks

25, 26, respectively. From the foregoing description of the preferred construction it will be apparent that during the dumping .operation the bracket T is held stationary and the scrap box proper pivoted about the center of the trunnions 4-0 and 41 by which the box is connected to the bracket.

The spacing of the hooks of the respective load grabs L and R are preferably the same so that either crane can be used to handle both ladles and scrap boxes, if necessary. When the crane A is used to handle the ladle H, the trunnions thereof are engaged in the apertures 44, 45 of the

hooks

25, 26 respectively.

While in the preferred embodiment of the invention shown, the bracket T is permanently connected to the scrap box S, it is to be understood that it could be independent of the scrap box, for example as shown in FIGS. 5 and 6 wherein the bracket T is similar to the bracket T of the preferred embodiment except for the fact that it is not pivotally connected to the box but includes a shaft 70 extending from one side of the bracket to the other, which shaft is removably secured in the same openings in which the trunnions 40, 41 of the preferred embodiment project. The dumping spout 31 of the scrap box shown is made of lighter material than that of the box proper and is so constructed as to provide a corner or offset at the left-hand end of the box proper within which the shaft or bar 70 may be engaged. In this instance the box S pivots about the shaft or bar 70 during the dumping operation.

From the foregoing description of the preferred embodiments of the invention it will be apparent that the objects, heretofore enumerated, and others have been accomplished and that there has been provided a novel and improved overhead apparatus for use in steel mills and the like which not only does not occupy valuable floor space but which c n be used to quickly change molten and/ or scrap metal into a furnace thus saving valuable furnace operating time which would be otherwise lost.

Although the preferred embodiments of the invention has been shown and described in considerable detail, it is to be understood that the invention disclosed is not limited to the particular constructions shown and described, and it is the intention to hereby cover all adaptations, modifications and uses of the invention which come within the practice of those skilled in the art to which the invention relates and the scope of the appended claims.

Having thus described our invention, what we claim is:

1. In a device for handling a box-like container having an opening in one end for dumping material from said open end, a bracket comprising side members, first support means on said side members adapted to pivotally support said container adjacent to said one end, second support means on said side members spaced from said last-named means in the direction away from said one end of said container, hook-like grab means adapted to detachably engage said second support means, and third means on said hook-like grab means adapted to detachably engage said side members and limit rotation thereof relative to said hook-like grab means in at least one direction as said container is pivoted.

2. In a crane having an overhead bridge, a crane trolley movable along said bridge, main hoist mechanism on said trolley comprising main hoist cable means, main grab means connected to said main hoist cable means, a box-like container having an opening in one end, members located at each of two opposite sides of said container other than said one end, means pivotally connecting said members to said container adjacent to said one end, means on said members spaced from said last-named means in the direction of an end of said container opposite said one end of said container engaged by said main grab means, means on said main grab means limiting rotation of said members relative thereto, auxiliary hoist mechanism on said trolley comprising auxiliary hoist cable means, auxiliary grab means connected to said auxiliary hoist cable means, means on the end of said container opposite to said one end engaged to said auxiliary grab means, said auxiliary hoist mechanism operative to raise said opposite end of said container relative to said open end to dump material contained therein from said open end, and means on said trolley frame depending therefrom and forming guide ways for receiving at least a portion of said main grab means when elevated to a predetermined position, said lastnamed means being operative to prevent lateral movement of said main grab means when engaged in said guide means.

3. In a crane having on overhead bridge, a crane trolley movable along said bridge, main hoist mechanism on said trolley comprising main hoist cable means, a device for handling a box-like container having an opening in one end comprising a bracket comprising side members, means on said side members adapted to pivotally support said container adjacent to said one end, trunnions on said side members spaced from said last-named means in the direction away from said one end of said container and toward an opposite end thereof, first hook-type grab meas to engage said trunnions and operatively connected to said main hoist cable means, auxiliary hoist mechanism on said trolley comprising auxiliary hoist cable means, second hook-type grab means to engage the end of said container opposite said one end and operatively connected to auxiliary hoist cable means, said auxiliary hoist mechanism operative to raise said opposite end of said container relative to said open end, and means on said trolley frame depending therefrom and forming guide ways for receiving at least a portion of said first hook-type grab means when elevated to a predetermined position, said last-named means being operative to prevent lateral movement of said first 'hook type grab means relative to said trolley when said hooktype grab member is engaged in said guide means.

4. In a device for transporting a box-like container and for pivoting a box-like container about an axis adjacent one end to dump material from said one end by raising an opposite end thereof, first support means located adjacent said one end of said container and having a part coaxial with said axis, second support means spaced from said first support means with said container being movable relative thereto, said second support means spaced from said first support means toward said opposite end of said container, a first member connected between said first and second support means, said first member including spaced means adapted to be engaged by a grab and prevent pivotal movement of said first member with said container, and means for raising said opposite end of said container relative to said one end to pivot said container about said axis.

5. A device of the type defined in claim 4 wherein said spaced means includes members projecting from said first member.

6. A device of the type defined in claim 4 wherein said first support means includes members projecting from sides of said container and fixed against movement relative thereto.

7. A device of the type defined in claim 4 wherein said first support means includes a member detachably connected With said first grab member and supportingly engaging said container.

8. A device of the type defined in claim 7 wherein said member is slidably engaged With said container.

9. In a crane operative to transport a box-like container between horizontally spaced locations having different elevations and to elevate a first end of the boxlike container to dump contents of the container there from, a main hoist including a flexible hoisting member having a grab for detachably supporting said container adjacent a second end thereof, auxiliary hoist means including a flexible hoisting member having a part for detachably supporting said first end of said container, and support means associated with said container and said main hoisting member, said support means including a first support part supporting said container for vertical movement and a second support part adjacent a second end of said container and a third support part spaced from said first and second parts and detachably connectible with said grab and a member at a side of said container rigidly interconnecting said support parts, said grab including a member enga-geable with said side member on said support means and operable to limit movement of said side member relative to said grab, said first end of said container being elevatable by said auxiliary hoist to rotate said container about said second support part of said support means, said container pivotally movable relative to said support means and said grab on operation of said auxiliary hoist to dump contents of said container therefrom.

10. The crane structure as defined in claim 9 and further including a trolley movable along an overhead track- Way and carrying said main and auxiliary hoists, and means rigidly connected to said trolley for preventing movement of said grab When said container is being dumped.

11. The crane of the type defined in claim 10 wherein said first support part extends from said side member transversely across and below said container and is spaced vertically from said third support part.

References Cited by the Examiner UNITED STATES PATENTS 1,362,560 12/1920 Coe 212 1,558,746 10/1925 Moore 212130 1,614,400 1/1927 Selman et a1. 29473 X 2,823,061 2/1958 Pottorf 294-73 3,111,228 11/1963 Anderson 212130 EVON C. BLUNK, Primary Examiner.

A. L. LEVINE, A. C. HODGSON, Assistant Examiners.

Claims

1. IN A DEVICE FOR HANDLING A BOX-LIKE CONTAINER HAVING AN OPENING IN ONE END FOR DUMPING MATERIAL FROM SAID OPEN END, A BRACKET COMPRISING SIDE MEMBERS, FIRST SUPPORT MEANS ON SAID SIDE MEMBERS ADAPTED TO PIVOTALLY SUPPORT SAID CONTAINER ADJACENT TO SAID ONE END, SECOND SUPPORT MEANS ON SAID SIDE MEMBERS SPACED FROM SAID LAST-NAMED MEANS IN THE DIRECTION AWAY FROM SAID ONE END OF SAID CONTAINER, HOOK-LIKE GRAB MEANS ADAPTED TO DETACHABLY ENGAGE SAID SECOND SUPPORT MEANS, AND THIRD MEANS ON SAID HOOK-LIKE GRAB MEANS ADAPTED TO DE-