US 2940791 A
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Description (OCR text may contain errors)
June 14, 1960 A. LoRENsoN 'E1-AL 2,940,791
APPARATUS FOR BREAKING AND LIFTING LINING Booms Filed Feb. 25, 1959 3 Sheets-Sheet 1 n A a l s a 1 n l i l @A Z5 INVENTORS Maxam Arron/Ef June 14, 1960 A. oENsoN Em 2,940,791
APPARATUS FOR BREAKING AND LIFTING LINING BODIES Filed Feb. 25, 1959 5 Sheets-Sheet 2 59 50 se 4Z 55 46 L 49 54 44 L 3727 INVENTORS NOEL PERTU/SET BY 6564,20 VICTOR .BE/NHARDT K11-MSM June 14, 1960 A. LoRENsoN ErAL 2,940,791
APPARATUS FOR BREAKING AND LIFTING LINING BODIES Filed Feb, 25, 1959 5 Sheets-Sheet 3 INVENTORS /@E/VSON United States Patent APPARATUS FOR BREAKING ND LIFTING I LINING BODIES Filed Feb. 25, 1959, Ser. No. 795,412
8 Claims. y (Cl. 294-67) This invention relates to apparatus for freeing and removing an adherent solid body, for example, a massive body of lining material, from an enclosing open-topped shell, and more particularly to breaking apart and lifting a half or other portion of such body of lining material from the shell, under circumstances where the body portion to be broken away is adapted to be engaged at 'opposite side regions thereof, in localities accessible between the body and the shell.
ln the electrolytic production of aluminum in reduction cells of conventional character, usually called pots, the material lim'ng the pots is introduced as paste and solidifled in place, and gradually hardens; after some time it fails and must be removed. These linings mayvary somewhat in composition and arrangement; a common example comprises a thick inner layer of carbon and an outer, thermal insulating layer of a suitable refractory, the whole gradually assuming a monolithic character over the life of the pot. The shell is usually a steel plate structure, externally braced, and having a complete arrangement of bottom and side Walls, against which the lining is packed and becomes adherent. Considerations vof size and weight often require for convenience that as part of the act of removal, the complete body of lining be broken in half or other parts; thus it is desirable to break off and lift, simultaneously, the first such half or other t portion, and then to remove the remaining half or portions in similar manner. It will be understood, however,
that the improved apparatus described below can in appropriate cases as with small whole linings,
half portions or portions greater or less than a half.`
be used, pots, for removing as Well as for breaking apart and lifting To prepare the lining for the specific breaking and liftl ing operation mentioned above, one end and the adjacent half of each side are freed by a pneumatic tool from the enclosing pot shell, exposing the steel collector bars embedded in the bottom of the pot (in the carbon portion) at right angles to its length; these -bars are then severed Y from the shell at their juncture therewith, as by an acetylene torch, leaving engageable extensions protruding from the body of the lining. The bottom of the lining, of course, at this point still adheres to the bottom of the shell, and the partially freed half of the lining is still v united with the unfreed half.
The removal of the body of the lining thus prepared, v
therefore, involves the application of an upward force on it in such way as to break it from the other portion and to free it from the shell, since it is desirable not to disturb the permanent installation of the shell on the potroom floor or other foundation. Conventionally the operation of breaking and liftingV the lining has.V been eiectuated through the Vapplication of `direct force of an overhead crane, suitably attached to Vthe collector bar ends. However, this method is attendedtwith considerable 4hazard and inconvenience, since the lining sometimes fails to break, in which case the entire lining and shell are 'suiciently high to allow it t lift thehalves' f lining separately thus may nevertheless become overloaded when the lining fails to break; moreover, in this contingency further and diiicult operations are required to effect the breaking and removal of the lining.
It is therefore, an object of the present invention to provide a safe, simple and ecient means of separating and lifting such lining portion from an enclosing shell, using force exerted by an overhead crane, yet avoiding the difficulties explained above, especially in respect to displacement of the shell along with the entire lining.
Another object is to provide such lifting means for breaking and removing a body of lining with relatively limited lifting force, as by a novel arrangement of levers aiording a sufficient mechanical advantage, for example, to enable a crane whose safe working load limit is not substantially greater than that necessary to accommodate the weight of a half of a .body of lining (i.e. a crane substantially lighter than would otherwise be required) to eiect the freeing of the lining without overloading; a special object being the provision of new lining removal apparatus wherein the distribution of forces exerted by the crane is such that the shell is held down while the lining within is broken and lifted, both to render the freeing operation more facile and to'obviate the possibility of the shell being lifted. Further objects of the invention will appear in the detailed description of its structure and operation hereinbelow. A The invention in one important embodiment comprises a frame, resting on the shell from which the material is to be removed; a pair of levers, respectively pivoted on portions of the frame extending beyond the shell, disposed upwardly and inwardly therefrom, and connected at their free ends with an overhead crane or other appropriate lifting means; and engaging means respectively pivotally dependent from the levers at a point intermediate the pivot and the free end of the lever, such engaging means being attached to the body to be lifted on opposite sides thereof, and so disposed on the levers as to afford a suitable mechanical advantage for the lifting means. These elements, in combination, are so constructed and ,arranged that upon application of a simultaneous upward force on the levers .bythe lifting means, a simultaneous upward :force of appropriate magnitude is applied on both sides to the body ofmaterial to be lifted, and an opposite down- ,wardforce is exerted through the frame as fulcrum on the enclosing shell, these opposite forces effecting the separation and lifting of the body from the shell.
The constructionand operation of the invention will be more fully explained in the description below, taken with the accompanying drawings, wherein: v
Fig. l is a perspective view, somewhat simplified, of an aluminum reduction cell or pot containing a body of lining material such as the invention may be adapted to remove;
Fig. 2 is a top plan view of the pot of Fig. l, with a portion of the lining broken away 4to illustrate an arrangement of collector bars therein and showing a' further portion of the lining freed from the pot shell, as in prepa ration for removal bythe invention;
Fig. 3 is a side elevational view of one important embodiment of the invention, somewhat simplified, showing the apparatus in position forV lowering to engage the body of lining in the pot;
Fig. 4 is a side elevational View of the apparatus of Fig. 3, showing it in engagement with the lining during the lifting thereof;
Fig. 5 is a top plan view of the apparatus of Fig. '3;
Fig. 6 is an enlarged detail view along the line 66 ofFig.4; Y' j l Fig. 7 is a further enlarged detail v-iew, in section along the line 7'- 7 of Fig. 6; A
Fig. 8 is a plan view of one lever arm' of the apparatus Yof Fig. 3;
` Vlirlllgfin lialfandfliftingffthe! separate rh Y Y thse plates,Y and throng may beninserted ahnfiv Y 34"(Figs. 3 and 5 )",heldj'nplacjeby a nui VAwhen th'eapparatns in Y@for mo ng i Y Y 4--- Y Ffg- 9" is' a Side dvatibnafW'ew ofthe' muffins-8L @Oranier rosfiiontrensvsealy aboveythe levers, andrrris FigiV I0 is 'an enlargedd'eail" ifi'ewpin section alongthe prevented from downwardrrotationby the transverse supline 1li-10 of Fig. 9; and Y port bars 2,9.Y Each of thesev levers'has a portion 41 ady Fig.. 1l4V saYieW seetiogn tllveline Y jacent the pivot shaft comprising apajr of channel mem-l theakpparatuswi'thlthelni ,3 specically plates@ are mgrdlyattacliedtovthewebsofthe channels.
Ataxiliiwar@ psi-tioniijeachgleyen arulgajpairfof vertical V support plates 47 aref'ri'gidly attachexfm pajrallelr'elation t0n the Si 9,f.bar&;4,l Mrespecv y-bearing holes I having a commonxis parallel to Vtheres ,Y ft 38. The vertical walls of each lever arm=46 are `rounded attheir 'outer ends, i.e. at -the ends nearest `the pivot 38, by a l?.1' 111'.l1dingVVV portionsjoffjthe 'H-dllliilds; ,44,-1Q-.P
shell or! otherwise the vsljoyvfn in Fjgsi 3",; Y4 Sfapdfl'll clnldesa horizontally 'elongatedffrarne' general de glaaamafbefpasl Y immane; the pivot marras-rangiert@ ,lifting lugs'o tobe engagedby afcrane hofA k 75 Vforgrca lis mon 'nfof y'the levers; Without st df: tant the?, pivot; shaft.: a plates orflngY the side off/'th Pot sharp ridges 59" to engage thercollec'tor bar ends4 25 securely, i.e. to prevent slippage. The pivot shafts-T52 are so disposed on the levers that the series of plate links 56, 57 and grappling plates 58 vertically dependent therefrom respectively pass between the freed sides 23 of the body of lining and the pot shell 20 ,whenv the apparatus is in position for removing lining.
When lining is to be removed Yfroman aluminum reduction pot with the apparatus described above, the lining 22 is first laterally freed or partly freed from the pot shell 20, preferably along one end, and most especially along half of each adjacent side, with a pneumatic tool; the exposed collector bars 24 embedded in thebottom of the lining transverse to the long axis of thepot are severed at their junctions with the shellY by an acetylene torch. The apparatus, with lbolt 34 in place and. the levers 40 resting parallel to each other in opposing position within the frame 26, is brought, by means of an overhead crane Wose hook 75 engages bolt 34, into position over the pot, i.e. with the long axis of the frame parallel to the collector bars and transverse to theV long axis of the pot, over the freed portion 23 of the lining, as shown in Fig. 3.
V'Ille apparatus is then lowered by the crane onto the pot shell, guided manually by the handles 36, 37, so that the l-beam sections 30 rest respectively on opposite side top edges 21 of the pot, and so that the dog stops .31 respectively abut the outer side edges of the pot, fixing the apparatus in position over the pot. The grappling plates 59 are thus lowered between the respective freed sides of the lining and the shell walls, and are brought manually into respective engagement with three adjacent collector bar ends 25 by fitting the bar ends into the grappling plate apertures 59. After removal of the crane hook, the bolt 34 is removed to permit upward rotation of the levers 40, and a double chain sling or the like is hooked to or otherwise passed through the apertures 50 at the extremity of each lever.
The sling being connected to the crane, upward movement of the crane cables or chains draws the levers 40 simultaneously upward, exerting a simultaneous upward force on both sides of the lining through the engagement of collector bar ends 25 with grappling plates 58. At the same time, there is exerted a simultaneous downward force on both sides of the shell through the frame 26, which acts as fulcrum for the levers. Continued upward motion of the crane thus pulls the lining upward, freeing it from the bottom of the shell, and most importantly, breaking it from the unfreed half of the lining, while the downward force exerted on the shell by the frame as fulcrum eifectively obviates the danger of the shell being lifted along with the lining.
That is to say, the breaking apart and the detachment of the lining from the shell is eiected with certainty and in a simple operation; while by appropriate arrangement of the levers, i.e. in disposition of the grappling pivot shafts or load points 52 and of the sling apertures or force points 51 with respect to the lever pivot shafts or fulcrums 3S, a high mechanical advantage is achieved, enabling the employment of a relatively light crane for the operation. In one particular case, the ratio of the distance 51-38 to the distance 52-38 was 8:l.5, affording a mechanical advantage of greater than 5.3; a crane with a safe working load limit of l tons thus was enabled to provide, within its safe limit, a lifting force of 40 tons through each lever on each side of the lining, for a total upward force of 80 tous, thereby safely and easily detaching the lining from the pot, whereas without the apparatus the crane could safely provide an upward force only of l5 tons, frequently insuicient to break the lining free. The use of the adjustable dog stops to secure the apparatus from slipping olf the frame during removal of the lining, and the peculiar configuration of the grappling apertures 59 to prevent slippage 'of the collectorv bars, -add a `further featurev of safetyt the operation; i .v
`When the lining has been freed from the shell, the apparatus appears as in Fig. 4, with the levers disposed upwardly and'inwardly from their pivot. points, and the body of lining suspended securely fromithe levers, on the grappling plates. Further upward motion of the Vcrane lifts `the lining free of the shell, and the'lining, still en- :gaged n theV apparatus, may be without further adjustment transported to another location as' desired. The apparatus canof course, then be utilized for'removing thev remaining body or bodies (i.e. half or other portions) from the shell, infsimilarfashion.
Thus the apparatus achieves the safe and convenient removal of bodies of lining from aluminum reduction pots, utilizing the upward force of a crane to provide opposite forces on the lining portion and the pot shell through an appropriate arrangement of levers von a frame andthus to effect positive breaking and detachment of .the lining from theshell; multiplying the force of the crane with a high mechanical advantage achieved through appropriate arrangement of the levers, to enable the use of a far smaller crane than wouldotherwise be necessary for the operation; and holding the lifted lining body securely to permit facile transportation thereof by the crane from the shell to another location.
It is to be understood that the invention is not limited to the specific devices herein disclosed but may be embodied in other forms without departure from its spirit.
l. Apparatus for lifting from an enclosing open-topped shell, a body of material which is engageable at transversely spaced, opposite regions thereof, comprising frame means having transversely spaced portions respectively adapted to rest on opposite parts of the shell that are adjacent to but outside said regions of the body, a pair of levers pivoted to the frame means at localities respectively adjacent said portions, each lever extending upwardly and transversely toward a point above the pivot locality of the other lever, means at the upper ends of the levers for applying lifting force simultaneously thereto, and a pair of grappling means respectively connected `to the levers at localities thereof spaced from the pivot localities and from the force-applying means, and engageable with the said body at said opposite regions thereof, for exerting lifting force thereon.
'2. Apparatus for lifting from an enclosing open-topped shell, a body of material which is engageable at opposite sides thereof within the shell, comprising frame means adapted to rest on opposite edges of the shell and having portions extending respectively beyond the shell, a pair of levers respectively pivoted to said portions and extending upwardly andv inwardly from. the frame means, means at the upper ends of the levers for applying lifting force simultaneously thereto, and a pair of grappling means respectively depending from the levers atl intermediate localities thereof and adapted for lifting engagement with the aforesaid opposite sides of the said body.
3. Apparatus as defined in claim 2, wherein the frame means includes stop means depending from the outer portions of said frame means and adapted to extend below the aforesaid edges of the shell, to engage Opposite side regions of said shell for preventing lateral displacement of the frame means.
4. Apparatus as dened n claim 2, wherein the frame means is shaped to receive the levers in substantially horizontal position for storage of same when the upper ends of the levers are relieved of lifting force.
5. Apparatus for lifting, from an enclosing open-topped shell, a body of material which is engageable at opposite sides thereof within the shell, comprising a -frame adapted to extend across the shell in seating abutment with opposite edges thereof, said frame including parts extending outwardly of the shell at both sides, a pair of levers respectively pivoted to the outwardly extending parts of the