US2743060A - Ball mill with risers on liners to throw balls and oversize material towards feed end of mill and to progress smaller balls and fine material towards discharge end of mill - Google Patents

Description

Aprll 24, 1956 A. c. DAMAN 2,743,060

BALL MILL WITH RISERS ON LINERS TO THROW BALLS AND OVERSIZE MATERIAL TOWARDS FEED END OF MILL AND TO PROGRESS SMALLER BALLS AND FINE MATERIAL TOWARDS DISCHARGE END OF MILL Filed Nov. 12, 1954 2 Sheetshee l L Q A. V mm v B w ow mm P /n J 1 mm E E o 5 on R om/ fiow ow Him}...

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BALL MILL WITH RISERS ON LINERS TO THROW BALLS AND OVERSIZE MATERIAL TOWARDS FEED END OF MILL AND TO PROGRESS SMALLER BALLS AND FINE MATERIAL TOWARDS DISCHARGE END OF MILL Filed NOV. 12, 1954 2 Sheets-Sheet 2 j l G.- 4

IN I 'EN'IOR.

Arthur C. Damon ATTORNEYS BALL MILL WITH RISERS ON LINERS'TO THROW BALLS AND OVERSIZE MATERIAL TOWARDS FEED END OF MILL AND 'TO PROGRESS SMALLER BALLS AND FINE MATERIAL TO- WARDS DISCHARGE END 'OF MILL Arthur C. Daman, Denver, C610, assignor to Mining Process and Patent Company, Denver, Colo., a corporation of Delaware I Application November 12, 1954, Serial No. 468,28

8 Claims. c1..z 41--1s3 .sizefeed material, toward the feed end of the mill while permitting the progressive movement of fine material and smaller balls through a series of restricted passages to the discharge end of the mill. The improved liner arrangement includes a plurality of lifter members which may be varied in their spacing on the liner member to provide a predetermined size opening between the members for the passage of fine material. The lifter members are arranged and proportioned to protect the bolt holes in the liner section. The arrangement and shaping of the liner sections and lifter members causes a crisscross counter fiow action of the material and the balls within the These and other objects and advantages may be more readily ascertained by referring to the following description and appended drawings in which:

Fig. 1 is a vertical longitudinal section, through a ball mill according to the present invention; 7 I

Fig. 2 is a fragmentary detail of the lifter members illus trating the crisscross arrangement of the ball and the material;

Fig. 3 is a fragmentary cross sectional view of a portion of the shell and liner arrangement illustrating thelifters and the arrangement thereof in relation to the rotation of the drum; and

Fig. 4 is an elevational view of a litter according to'the arrangement illustrating the height of various portions of the lifter above the liner.

Referring to Fig. 1 of the drawings, and-11 represent, respectively, concrete mill beds or foundations for a ball mill at the feed and discharge end thereof. A ball mill feed'head -12 has its hub 13 journalledfor rotation in a bearing 14. The discharge head 15 has its'hub 16 journalled for rotation in a bearing17. A ring gear 18 is secured to the discharge end 15, and power is applied thereto for rotating or operating the grinding mill; r

- A shell 19 is secured to the heads 12 and 15, forming the drum portion of the ball mill. I A sectioned liner 20 is secured to the shell 19 to complete'the main. portion of the assembly. A feed scoop member 21 feeds a frusto-conical sleeve 22, located within the hub 13, and which is-in communication wth the interior of the mill. Material to be ground and grinding balls are fed by the scoop member through the sleeve into the mill. The end of ,the mill, adjacent the-head 12, is provided with an end liner'20a having a central opening 23 providing communication from the sleeve 22 to the interior of the mill.

. The discharge end of the mill'is provided with a liner 20b, abutting the discharge head 15, which is provided 2,743,060 ra m a Apr. 24, 1956 ice tional in ball mills, and the assembly of the conventional v parts is'more ,or less standard practice.

In accordance with the present invention, .the liner. sections or plates 20 are provided with a plurality of main lifter or riser members spaced apart, in the central portion of the ball mill. Feed end lifters or risers 31 are provided at the feed end of the ball mill, and discharge end lifters or risers 32 are provided at the discharge end there: of.' The lifters 30 are generally of the shape of rectangular hooks. The lifter 30 comprises a central sloping section 33,. which is substantially longitudinally aligned with the drum, a tapered tail or long leg portion 34, which is extended at an angle to the longitudinally aligned sections 33, and a head or short leg portion 35 which is, likewise,

set at an angle to the longitudinally aligned sections 33.-

. A riser 30is positioned so as to be in front of eachbolt hole 28, in relation to the rotation of the ball The riser 31 is constructed similarly to the riser 30, and it includes a central sloping portion '36 that extends longitudinally along the shell of the liner, a tapered long leg portion 37 extending from the longitudinal portion at an angle thereto along the shell, and a head portion 38 which extends at an angle from the section 36, on the opposite side of the tapered section 37. The long leg 37 is angularly extended from the portion 36 away from the direction, of rotation, but the short leg 38 extends angularly into the direction of rotation. The short leg 38 tends to keep grindi ing balls and material away from the liner 20a. Theriser 32 comprises a portion 39 that extends longitudinally along the liner of the ball mill, which portion is tapered from the feed end toward the discharge end. A head end 40-is'sewith a central opening 24. A'sleeve member'25 is secured v within the opening 24. The central opening 24 communi cured to the longitudinal section 39 and itextends at an angle downwardly from the longitudinal section, The upper surface 39a of the riser 32 slopes from the fced to the discharge end thereof. This riser 32 tends to throw ground material toward the discharge and the balls toward the feed end. a v

As illustrated in detail in Fig. 2, the risers provide passages for longitudinal distribution of material and the balls in the ball mill. The short leg 35 whichis of greater thickness than the long leg 34 tends to throw balls Which are of a larger diameter than the width of the passage between the short leg 35 and the next adjacent long leg ,34, toward the feed end. Material which is smaller than the distance between the short leg and its next adjacent" long leg tends to move toward the discharge end. For example, a ball 50 which has a diameter greater than th'edis'tance between the long leg 34 and its next adjacent short leg-35, is thrown back toward the feed end over surface 340, as indicated by the arrow, where the movement of the riser 30 is upward, as indicated by arrows near the riser. Small particles 51 pass'through the pas: sage between the short leg 35 and the long'leg 34 so that they areactually moved toward the discharge endotthe ball mill. Material of small size and small balls, therefore, move from the feed end to the discharge etid of the mill. The risers are spaced apart to provide the restrictive passage therebetween, and the of the passages may be changed from the feed to the discharge end .to perform various types .of ,grinding. The width of the passages may, for example, be progressively narrowed 'fromthe feed to the discharge end. The sh'ortjl'eg of the risers tends to throw large balls back to the feed end of the mill, while the restrictive passage permitssmall material tomove toward the discharge end of the mill. If it is'desired, in the charging of the ball mill, small balls may be introduced at the discharge end and "the large balls may be introduced at the feed end, although it is possible and satisfactory to introduce .both small and largeballs at the feed end of the mill along with material to be ground. In either-case, the large balls'tend to stay toward the feed end .of themill while the smaller balls work their way to the discharge of the mill. Oversize material tends to travel toward the feed end, similarly to the balls, :and the smaller material tends 'to travel toward the discharge end. Thus, a crisscross, counterflow movement of the finer material and finer balls is achievedin relation to the larger balls and larger material to be ground.

The plates or sections 20 are provided with longitudinal ridges 41 at one end thereof to aid the grinding action'of the balls on thematerial in the mill. The ridges increase the height of the cascade and increases grinding eificiency.

"While the risers have been shown of a particular shape, that is, -with-one short leg and one long leg, it is obvious that by changing the configuration of the risers, various grinding actions may be obtained and various types of grinding may be accomplished. Further, the change of spacing of the "risers in .the ball mill will provide various grinding actions. The risers 31 tend to keep the balls and large material away from the liner 7'0aon the end of the ball mill, likewise the risers 32 aid in maintaining the balls away from the liner end 20b on the discharge end. It is to be understood further that the liner sections or plates '20 together'withthe reflective flanges 41 secured thereon, the lifter members and the angle parts may be formed from any suitable and desirable material, for example, ferrous metal, steel, rubber, or the like.

While the "invention has been illustrated with respect to a specific embodiment, there is no intent to limit the invention to the particular details so illustrated, except insofaras set forth in the following claims.

I claim:

1. Asectional liner for crushing mills utilizing balls orthe like as 'a crushing medium comprising a plurality of liner members mounted on the face of said mill, and being shapedfor cooperative positioning within said mill to shield the inner surface of the mill from destructive abrasion, raised flanges at spaced positions on the inner material crushing surfaces of said members, raised porlions extending from the terminal ends of said flanges toward but out of contact with adjacent portions, one of said raised portions being at least about as high as said flange and extending outwardly at an angle thereto, the other said raised portion being tapered downwardly and extending outwardly from the opposite end of said flanges, whereby to provide helically aligned passages therebetwecn,- said passages being of 'sufiicient dimension to provide 'for the free iiow of small sized particles toward the discharge end of said mill, while preventing the passage of crushing balls and particles larger than the dimensions of said passage through the same toward the feed end.

2. Structure in accordance with claim 1 wherein the liner members, flanges and raised portions are formed of ferrous metal.

3. Structure in accordance with claim 1 wherein the linerlmembers, flanges and raised portions are formed unitarily of steel.

4. Structure in accordance with claim 1 wherein the *liner' members, flanges and "raised portions are formed selectively of rubber.

5. A sectional liner for rotary crushing mills utilizing balls or the like as a crushing medium comprising a plurality of curved liner members mounted on the inner surface of said milLsaid members being shaped for cooperative positioning within said mill to shield the inner surface of the min from destructive abrasion, raised flanges on the inner material crushing surfaces of said members at spaced positions, raised portions extending from the terminal ends of said flanges toward but out of contact with adjacent portions, said passages being of sufficient dimension to provide for the free flow of small sized particles therethrough toward the discharge end of said mill while preventing the passage of crushing balls and particles larger than the dimensions of said passage and through the same toward the feed end of the mill, saiddincr members being provided with openings therethrough in positions adjacent said flanges and raised portions onthe side of said flanges opposite the direction of rotation ofsaid mill, and fastening means for insertion'throug'h said openings for securing said liner members to the inner surface of said mill.

6. A sectional 'liner for crushing mills utilizing balls or the like as a crushing medium comprising a plurality of curved liner members mounted on the inner surface of said mill, said members being shaped for cooperative positioning within said mill to shield the inner surface of the mill from destructive abrasion, raised substantially V-shaped flanges on the inner material crushing surfaces of said liner members at spaced positions arranged to align adjacent flanges in a plurality of directions, the legs of said fiangescxtending towardbut out of contact with the legs of adjacent flanges to provide helically aligned passages therebetween, said passages being of suflicient dimension to provide for the free flow of small sized particles therethrough toward the discharge end of said mill while preventing the passage of crnshingballs and particles larger than said dimensions and throwing the same toward the feed end of the mill, and said flanges being spaced circumferentially apart a distance .circumferentially suflicient to allow the crushingball'sto come into contact with the inner crushing surface of saidliher members to effect particle size reduction of the material charged into the mill.

"7. A sectional liner for rotary crushing mills utilizing balls orthe like as a crushing medium comprising a plurality of curved liner members mounted in said mill, said members being shaped for cooperative positioning within said mill to shield the inner surface of the mill from destructive abrasion, raised v shaped flanges on the inner material crushing surfaces of said liner members at spaced positions arranged to align adjacent flanges in two directions, said flanges being tapered from one terminal end to the other end thereof, the terminal ends of said flanges extending toward but out of contact with the adjacent flanges to provide 'helically arranged passages therebetWCBIlySfild passages being-of sufficient dimension to provide for the free flow of small sized particles therethrough toward the discharge end of said mill While preventing the passage of-crushing bal-ls and particles larger than said dimension and throwing the same toward the feed end of said mill, and saidfianges being spaced circumferentially'apart a distance sufficient'to allow the crushing balls to come into contact with the inner crushing surface of said members to cause particle size reduction of the material charged into the'mill.

8. A sectional liner for rotary crushing mills utilizing balls or thelike as a crushing medium comprising a plurality of curved liner members mounted in said mill and shaped for cooperative positioning within said mill to shidld-thelinner surface of the mill from destructive abrasion,.raised V-shapedjianges on the inner material crushing surfaces of said liner members at spaced positions arranged to align adjacent flanges in a plurality of direc- 5 tions, the terminal ends of said flanges extending toward but out of contact with the adjacent flanges to provide helically arranged passages therebetween, said passages being of suflicient dimension to provide for the free flow of small sized particles therethrough toward the discharge end of said mill while preventing the passage of crushing balls and particles larger than the dimensions of said passages, a projecting rib on the leading edge of said liner members out of contact with said flanges, said flanges and said projecting ribs being spaced apart each from each a distance sufiicient to allow the crushingballs to come into contact with the inner crushing surface of said members to cause further particle size reduction of the materials 5 charged into the mill.

References Cited in the file of this patent FOREIGN PATENTS 475,551 France Mar. 8, 1915

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