Improved cylinder screen of ball mill

Abstract

The utility model discloses an improved cylinder screen of a ball mill. A cylinder frame comprises an axial framework and a circumferential framework which are fixed with each other. The drum screen further comprises a plurality of detachable trapezoidal flat steel bars, and gaps between the adjacent trapezoidal flat steel bars serve as screen holes of the drum screen. A plurality of trapezoid grooves are evenly formed in the inner side of the circumferential framework in the circumferential direction, and the trapezoid flat steel bars are embedded in the trapezoid grooves. The drum screen further comprises a spiral feeding plate used for extruding and fixing the trapezoidal flat steel bars from the inner side. The spiral feeding plate is detachably connected to the circumferential framework or the axial framework. The screening efficiency is higher, the screen drum has higher impact strength, and the screen drum can be locally replaced when locally deformed or locally excessively abraded.

Description

Technical Field

[0001] The utility model relates to a cylindrical screen of a ball mill for ore dressing, belonging to the technical field of ore dressing machinery. Background Art

[0002] In the ore dressing system, the ball mill is connected to the drum screen through a flange. After the raw ore is ground by the ball mill, it enters the drum screen for screening. The fine-grained ore enters the next ore dressing process, and the coarse-grained ore returns to the ball mill for further grinding. Since the raw ore, including gold ore, has an irregular shape and the ore itself has a high hardness, it has strong abrasiveness and great wear on the screen, which in turn shortens the service life of the drum screen. In actual use, it was found that when the ball mill was in good operating condition, the drum screen would start to wear and leak after about six months of use, causing the entire ball mill system to shut down.

[0003] The current cylindrical screens generally include the following two categories. The first category connects and fixes the wire mesh to the cylinder frame to form the cylinder wall. For example, the Chinese authorized invention patent with announcement number CN103301910B discloses "a cylindrical screen for pre-screening of slurry at the discharge port of a ball mill and its assembly process". According to the description

[0021] , two ear plates and two screen plates are welded into a screen frame, and then the mesh wire is respectively passed through the wire holes on the two screen plates to be tightened and welded to the screen plates to form a screen. Its main disadvantage is that the screen is usually of low strength and is easily deformed by impact, resulting in changes in the gaps or even being punctured, and its service life is difficult to meet the requirements for metal ore screening. In addition, the patent's spiral guide trough is fixed to the cylinder screen frame by welding, which is not convenient for disassembly and replacement.

[0004] The second type uses screen plates to make the cylinder wall, such as the Chinese utility model with announcement number CN206793885U, which discloses "a dry ball mill material screening device". According to the description

[0022] , the cylindrical screen is a cylindrical structure formed by welding several screen plates with meshes. This type of design has the characteristics of high strength of the cylindrical wall plate, good wear resistance and not easy to deform, but the proportion of effective mesh is low, resulting in a reduced screening efficiency of the cylindrical screen. Utility Model Content

[0005] The technical problem to be solved by the utility model is to provide an improved ball mill drum screen with higher screening efficiency, a higher impact resistance of the screen drum and the ability to perform local renewal in the event of local deformation or local excessive wear.

[0006] The technical solution of the utility model is as follows:

[0007] An improved ball mill drum screen comprises a cylindrical drum frame, a feed end of the drum frame is provided with a flange for connecting to the discharge end of the ball mill, and the discharge end is open, the drum frame comprises an axial frame fixed to each other and a circumferential frame fixed to the axial frame, the drum screen also comprises a plurality of detachable trapezoidal flat steel bars, and the gaps between adjacent trapezoidal flat steel bars serve as sieve holes of the drum screen; a plurality of trapezoidal grooves are evenly distributed on the inner side of the circumferential frame, and the trapezoidal flat steel bars are embedded in the trapezoidal grooves; the drum screen also comprises a spiral feeding plate for squeezing and fixing the trapezoidal flat steel bars from the inside; the spiral feeding plate is detachably connected to the circumferential frame or the axial frame.

[0008] Preferably, a connecting plate is welded to the inner side of the spiral feed plate; the connecting plate is detachably connected to the circumferential frame or the axial frame by connecting bolts.

[0009] Preferably, the width of the trapezoidal flat steel bar on one side of the trapezoidal groove opening is greater than that on the opposite side, so as to ensure that the gap between adjacent trapezoidal flat steel bars gradually expands from the inside to the outside.

[0010] Equivalent to the prior art, the utility model has the following beneficial effects.

[0011] First, the utility model clamps the trapezoidal flat steel bars made of wear-resistant steel plates into the trapezoidal notches on the inner side of the cylinder frame, uses the gaps between adjacent trapezoidal flat steel bars as mesh holes, and fixes the trapezoidal flat steel bars to the cylinder frame from the inside with the aid of a spiral feed plate. On the one hand, the mutually combined trapezoidal flat steel bars and the cylinder frame improve the impact strength and wear resistance of the cylinder, and extend the service life of the cylindrical screen; on the other hand, the opening area of ​​the cylinder wall is large, and the screening efficiency is high; thirdly, when one or several of the trapezoidal flat steel bars are partially deformed or excessively worn, the spiral feed plate can be removed by removing the connecting bolts, and then the trapezoidal flat steel bar to be updated can be knocked from the outside to the inside to make it fall off, making replacement more convenient; fourthly, since the spiral feed plate of the utility model is a detachable connection, the spiral feed plate can be replaced more conveniently.

[0012] Second, the gap cross-section between adjacent trapezoidal flat steel bars of the utility model is a trapezoid with a larger outer bottom than an inner bottom. After the fine-grained ore passes through the narrow inner opening with the help of centrifugal force, the resistance to discharge from the mesh is very small, and the mesh is not easily blocked, which greatly reduces the workload of mesh cleaning. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 The overall structure and appearance of the embodiment of the utility model are shown in FIG.

[0014] Figure 2 It is a radial cross-sectional schematic diagram of the mesh part of the embodiment of the utility model;

[0015] Figure 3 It is a radial cross-sectional schematic diagram of the circumferential skeleton part of an embodiment of the utility model;

[0016] Figure 4 This is a schematic diagram of the inner structure of the cylinder frame part of an embodiment of the utility model.

[0017] In the figure, 1. axial skeleton; 2. flange; 3. trapezoidal flat steel bar; 4. circumferential skeleton; 5. spiral feed plate; 6. connecting plate; 7. connecting bolts. DETAILED DESCRIPTION

[0018] The present invention is further described below in conjunction with the embodiments and drawings.

[0019] like Figure 1 The embodiment of the utility model comprises a cylindrical drum frame, the feed end of the drum frame is equipped with a flange 2 for connecting with the discharge end of the ball mill, and the discharge end is open as a discharge port. The drum frame comprises four axial frames 1 parallel to each other and five circumferential frames 4 welded to the axial frames 1.

[0020] Combination Figure 1 , Figure 2 and Figure 3 The present embodiment further comprises a plurality of detachable trapezoidal flat steel bars 3, and the gaps between adjacent trapezoidal flat steel bars 3 serve as the sieve holes of the cylindrical screen. A plurality of trapezoidal grooves are evenly distributed circumferentially on the inner side of the circumferential skeleton 4, and the trapezoidal flat steel bars 3 are embedded in the trapezoidal grooves.

[0021] This embodiment further includes a spiral feed plate 5 for pressing and fixing the trapezoidal flat steel bar 3 from the inside. The spiral feed plate 5 is detachably connected to the circumferential skeleton 4 or the axial skeleton 1. For the convenience of assembly, the spiral feed plate 5 can be installed and disassembled in sections.

[0022] Specifically, a connecting plate 6 is welded to the inner side of the spiral feed plate 5 , and the connecting plate 6 is detachably connected to the circumferential skeleton 4 or the axial skeleton 1 through connecting bolts 7 .

[0023] Furthermore, the width of the trapezoidal flat steel bar 3 on one side of the trapezoidal groove is greater than that on the opposite side, so as to ensure that the gap between adjacent trapezoidal flat steel bars 3 (in the radial direction) gradually expands from the inside to the outside. Figure 2 Adjacent trapezoidal flat steel bars 3 form a sieve hole with a trapezoidal cross section, with the short side of the trapezoidal sieve hole inside and the long side outside, which is conducive to the rapid passage of materials through the sieve hole during screening and better avoids clogging. At the same time, the trapezoidal cross section of the trapezoidal groove cooperates with the trapezoidal cross section of the trapezoidal flat steel bar 3, which is more convenient for assembly.

[0024] Preferably, the spiral direction of the spiral feed plate is consistent with the rotation direction of the drum screen. The trapezoidal flat steel bar is preferably a NM500 wear-resistant steel plate.

[0025] When in use, the cylindrical screen flange is connected to the discharge end flange of the ball mill through bolts, and the ball mill drives the cylindrical screen to rotate synchronously with the ball mill.

[0026] The following examples illustrate the assembly and disassembly methods of the present invention.

[0027] During assembly, first install the trapezoidal flat steel bar 3 into the trapezoidal groove by knocking. Then install the spiral feed plate 5 onto the circumferential frame 4 or the axial frame 1 through the connecting bolts 7 and press the trapezoidal flat steel bar 3 from the inside. When the spiral feed plate 5 is worn or deformed, remove the connecting bolts 7 and replace the new spiral feed plate 5. When the trapezoidal flat steel bar 3 is worn or deformed and needs to be repaired or replaced, first remove the spiral feed plate 5, and then remove the trapezoidal flat steel bar 3 to be replaced from the trapezoidal groove by knocking.

Claims

1. An improved ball mill drum screen, comprising a cylindrical drum frame, wherein a flange (2) for connecting to a ball mill discharge end is mounted at the feed end of the drum frame, and the discharge end is open, wherein the drum frame comprises an axial frame (1) fixed to each other and a circumferential frame (4) fixed to the axial frame (1), characterized in that: The cylindrical screen further comprises a plurality of detachable trapezoidal flat steel bars (3), the gaps between adjacent trapezoidal flat steel bars (3) serving as screen holes of the cylindrical screen; a plurality of trapezoidal grooves are evenly distributed circumferentially on the inner side of the circumferential frame (4), the trapezoidal flat steel bars (3) being embedded in the trapezoidal grooves; the cylindrical screen further comprises a spiral feed plate (5) for pressing and fixing the trapezoidal flat steel bars (3) from the inner side; the spiral feed plate (5) is detachably connected to the circumferential frame (4) or the axial frame (1).

2. The improved ball mill drum screen as claimed in claim 1, characterized in that: A connecting plate (6) is welded to the inner side of the spiral feed plate (5); the connecting plate (6) is detachably connected to the circumferential frame (4) or the axial frame (1) via connecting bolts (7).

3. The improved ball mill drum screen according to claim 1 or 2, characterized in that: The width of the trapezoidal flat steel bar (3) on one side of the trapezoidal groove opening is greater than the width on the opposite side, so as to ensure that the gap between adjacent trapezoidal flat steel bars (3) gradually expands from the inside to the outside.

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