WO2016141716A1

WO2016141716A1 - Coal classifying screen

Info

Publication number: WO2016141716A1
Application number: PCT/CN2015/092598
Authority: WO
Inventors: 马琳
Original assignee: 四川重盟电力设备制造有限公司
Priority date: 2015-03-12
Filing date: 2015-10-23
Publication date: 2016-09-15
Also published as: CN104722472A

Abstract

A coal classifying screen, comprising a housing (2), a material distribution plate (14), a roller screen shaft (3) and a screen strip screen shaft (4). The material distribution plate (14) is obliquely provided below a feeding hole (23) of the housing (2), the roller screen shaft (3) and the screen strip screen shaft (4) together constitute a screen surface of the classifying screen, and material guide screws (6) are provided in the roller screen shaft (3) and the screen strip screen shaft (4) separately. Each material guide screw (6) consists of a forward material guide screw (6.1) and a reverse material guide screw (6.2), the forward material guide screw (6.1) being fixedly installed on one side of the interior of the roller screen shaft (3) or the screen strip screen shaft (4), and the reverse material guide screw (6.2) being fixedly installed on the other side of the interior of the roller screen shaft (3) or the screen strip screen shaft (4). Anti-blocking holes (10) are provided at two ends of the roller screen shaft (3) and the screen strip screen shaft (4) separately. The coal classifying screen achieves uniform material distribution, avoids material blocking inside a screen surface and a screen shaft, and has the prominent advantages of high screening efficiency, strong impact resistance and the like.

Description

Coal grading screen

Technical field

The invention relates to a screening device for coarse and fine coal materials, in particular to a coal grading sieve in the field of coal and mining.

Background technique

The circulating fluidized bed boiler of a thermal power plant needs to burn coal gangue particles with a certain proportion of particle size. In coal coal materials, because the coal material contains a large amount of qualified particle size and does not need to be repeatedly broken, it is necessary to pass the sieve to the qualified particle size. The coal material is separated to reduce the amount of excessive crushing, so that the combustion of the coal material is more in line with the boiler combustion curve. In the coal handling system of the power plant, the screening efficiency of the screening machine, the coal blocking situation, the uniformity of the cloth, and the cycle of repairing and replacing the fittings directly affect the combustion curve of the boiler. At the same time, the screening efficiency, coal plugging situation and uniformity of the screening machine will directly affect the efficiency of the subsequent crushing equipment.

The benefits of improving the efficiency of coal sieving are: 1. Reduce the power consumption of the main motor of the crusher; 2. Reduce the amount of over-crushing, make the combustion of coal materials more in line with the combustion curve; 3. Reduce the amount of treatment to extend the hammer of the crusher. The service life.

The phenomenon of coal plugging is a common practice in coal handling systems of thermal power plants, especially in the case of heavy coal water, large amount of coal gangue, poor fluidity of coal materials, etc. Solving the screen conveying of the screening machine is equivalent to cutting off the coal. The root cause of the phenomenon.

The uneven cloth is also the soft rib of most screening machines. The benefits of uniform cloth to the subsequent crusher are: 1. The wear of the main rotor of the crusher is evenly distributed; 2. The main rotor is concentrically beaten to extend the life of the main motor; 3. It is more conducive to Adjustment of particle size.

At present, the power plant sieving machine mainly uses vibrating screen, rotary screen, cross screen, roller screen and so on. Among them, the shortcomings of vibrating screen are: low output, low screening efficiency and frequent coal plugging; the disadvantages of rotary screen are: low output, low screening rate, frequent coal plugging, and no cloth; the disadvantage of cross screen is: high motor power The blade is seriously worn, the impact resistance is poor, and the maintenance period is short; the disadvantage of the roller screen is that the screening efficiency is low.

For example, the invention is a screening device of a vibrating roller screen (CN102310041A), which comprises a screen box, a roller screen surface, a vibrator, a vibration damping support device and a base. The screen surface is composed of a plurality of sets of rollers and is connected. It is vibrated by vibrator and geared. The angle of the screen surface is 0-90°. In fact, the screen plate is changed to a roller. The structure of the roller screen is complicated, the screen shaft is a solid screen shaft, and only a few screen slits are effectively screened. Therefore, the screening efficiency is low, the motor power is large, and the utility is poor.

Another example is the screening device of the new type of roller screen (CN101091950A), which comprises a sieve box, a dial, a sieve shaft and a speed reducer. The coal material is conveyed and permeable under the rotation of the dial, and the device actually It is a kind of cross screen. After the dial on the dial is put into operation, the dial and the blade are seriously worn and difficult to replace, and the impact resistance of the front end of the inlet is poor, and the screening of the multi-size coal material cannot be realized.

Summary of the invention

The technical problem to be solved by the invention is that, according to the problems existing in the prior art, a novel coal grading screen is provided, which solves the problems of low screening efficiency, insufficient output, inability to fabric, serious wear and poor impact resistance of the conventional screening equipment. , Screen surface blockage, screen shaft blocking, difficult maintenance, short replacement parts and other issues.

The technical problem to be solved by the present invention is achieved by the following technical solution: a coal grading screen comprising a casing, a cloth board, and a drum screen shaft and a screen sieve shaft, the cloth board being obliquely disposed under the feeding port on the casing The drum screen shaft and the sieve screen shaft together constitute a sieve surface of the grading sieve, and the roller screen shaft and the sieve screen shaft are respectively provided with a guide spiral, and the guide spiral is guided by the spiral and the reverse guide a spiral composition, the positive guide is fixedly mounted on one side of the drum screen shaft or the screen screen shaft, and the reverse guide is fixedly mounted on the other side of the drum screen shaft or the sieve screen shaft. Both ends of the drum screen shaft and the sieve screen shaft are respectively provided with anti-blocking holes.

Preferably, the screen screen shaft is provided with a screen slit.

Preferably, the screen screen shaft comprises a plurality of screen bars and a flange piece, the screen bars being connected between the flange sheets, and a gap is formed between the screen bars.

Preferably, the screen strip on the screen screen shaft comprises a movable screen strip and a fixed screen strip, and the movable screen strip is arranged in a staggered manner with the fixed screen strip.

Preferably, the sieve screen shaft comprises a fixed screen strip, a movable screen strip, a first supporting flange piece, and a first end movable flange piece and a fixed flange piece, wherein the first supporting flange piece is located at a relative position Between the two first end movable flanges of the vertical body, fixed flanges are respectively disposed on the outer sides of the two first end movable flanges, and the fixed screen strips respectively and the fixed flange piece and the first end portion The movable flange is fixedly coupled to the first support flange, and the movable screen is movably connected between the first end movable flange and the adjacent first support flange, and the first end is movable Anti-blocking holes are provided between the blue plate and the fixed flange.

Preferably, the sieve screen shaft comprises a fixed screen strip, a movable screen strip, a second supporting flange piece, and a second end movable flange piece and a fixed flange piece, wherein the second supporting flange piece is located at a relative position Between the two second end movable flanges, a fixed flange is respectively disposed on the outer sides of the two second end movable flanges, and the fixed screen is fixedly connected to the fixed flange and the adjacent one. Between the second end movable flanges, a movable screen strip is movably connected between the second end movable flange and the adjacent second support flange, and the flange is fixed and fixed at the second end. Flange Anti-blocking holes are provided between.

Preferably, in the sieve screen shaft, a plurality of convex tapered teeth are arranged on the outer surface of the movable screen strip, and the tapered teeth on the adjacent movable screen strips are staggered.

Preferably, a toothed partition plate is disposed between the upper portion of the two sides of the drum screen shaft and the sieve screen shaft and the inner wall of the casing.

Preferably, the screen strip on the sieve screen shaft is cut off on the outside of the toothed partition to form an anti-blocking hole.

Preferably, the cloth board is a pull-type cloth board.

Preferably, the angle of the screen surface composed of the trommel shaft and the sieve screen shaft is set to be 0 to 75°.

Compared with the prior art, the beneficial effects of the present invention are:

(1) High screening efficiency. The screening efficiency depends on the size of the screen area. The coal grading screen of the present invention has high screening efficiency because the coal shaft is not blocked in the screen shaft.

(2) Strong impact resistance and wear resistance. When the large piece of coal material is dropped from the pull-type cloth board and dropped onto the drum screen shaft, the drum screen shaft can withstand a strong impact force.

(3) Excellent fabric function. The coal material falls onto the pull-type cloth board to break the columnar structure is the first cloth; from the pull-type cloth board to the drum screen shaft, once again breaking the elliptical structure is the second cloth; through the rotating screen wave wave conveying The third cloth is used. Therefore, the coal grading screen cloth of the present invention is uniform, the coal pile thickness of the screen surface is thin, and the coal permeable rate is high.

(4), do not block the material. The sieve surface of the coal grading screen of the invention is composed of a sieve shaft, and each screen shaft is provided with a transmission shaft, a chain, a sprocket and a bearing seat, and the gear motor is connected with the chain to rotate, so that the screen surface can be forcibly conveyed to prevent the material from being blocked. occur. In addition, since the qualified coal material smaller than the sieve joint falls into the sieve screen shaft, the centrifugal force generated by the rotation of the screen sieve shaft will be smaller than that of the sieve joint and fall into the qualified discharge passage below the sieve surface; When the coal material slightly larger than the sieve joint falls into the sieve screen shaft, the coal material can be forcibly pushed to the anti-blocking holes at both ends of the screen shaft through the guide spiral or the guide piece provided in the screen sieve shaft, and the coal material is discharged. It is discharged into the blanking passage between the casing and the tooth-shaped partitioning plate, so that the screen does not block the material in the sieve shaft.

(5), easy to repair and replace. When it is necessary to replace the worn screen shaft, simply separate the screen shaft from the drive shaft and replace it with a new one. When replacing the pull-out fabric, the worn fabric is directly pulled out and replaced with a new pull-out fabric.

(6), adapt to a variety of particle size conditions. When the working condition needs to screen the coal materials of two or more particle sizes, the screening of the plurality of particle sizes can be achieved by increasing or decreasing the diameter of the screen joint on the screen shaft.

DRAWINGS

Figure 1 is a front elevational view of a coal grading screen of the present invention.

Figure 2 is a plan view of the coal grading screen of the present invention.

Figure 3 is a side view of the coal grading screen of the present invention.

4 is a schematic view of the toothed partitioning plate of FIG. 1.

Figure 5 is a schematic view of the drum screen shaft of Figure 1.

Figure 6 is a schematic view of the screen screen shaft of Figure 1 (Embodiment 1).

Figure 7 is a schematic view of the flange piece of Figure 6.

Figure 8 is a schematic view of the screen screen shaft of Figure 1 (Embodiment 2).

Figure 9 is a schematic illustration of the fixed screen of Figure 8.

Figure 10 is a schematic illustration of the movable screen strip of Figure 8.

Figure 11 is a front elevational view of the first support flange of Figure 8.

Figure 12 is a side elevational view of the first support flange of Figure 8.

Figure 13 is a front elevational view of the first end movable flange of Figure 8.

Figure 14 is a side elevational view of the first end movable flange of Figure 8.

Figure 15 is a front elevational view of the fixed flange of Figure 8.

Figure 16 is a side elevational view of the fixed flange of Figure 8.

Figure 17 is a schematic view of the screen screen shaft of Figure 1 (Embodiment 3).

Figure 18 is a front elevational view of the second support flange of Figure 17.

Figure 19 is a side elevational view of the second support flange of Figure 17.

Figure 20 is a front elevational view of the second end movable flange of Figure 17;

Figure 21 is a side elevational view of the second end movable flange of Figure 17.

Marked in the figure: 1-size sieve for coal, 2-shell, 3-roller screen shaft, 4-screen sieve shaft, 5-shaped partition plate, 6-guide spiral, 6.1-guide spiral 6.2-Reverse guide spiral, 7-size observation hole, 8-screen, 9-slot, 10--blocking, 11-feeding channel, 12-flange, 13-screen viewing hole, 14 - fabric board, 15-split board, 16-detachable drive shaft, 17-bearing, 18-reduction motor, 19-chain, 20-sprocket, 21-seal, 22-support, 23-feed Port, 24-first qualified particle size discharge port, 25-second qualified particle size discharge port, 26-unqualified particle size discharge port, 27-fixed screen bar, 28-active sieve bar, 29-cone Tooth, 30 - first support flange, 31 - first end movable flange, 32 - movable hole, 33 - fixing hole, 34 - trapezoidal hole, 35 - fixed flange, 36 - connection hole, 37 - Second support flange, 38 - second end movable flange.

detailed description

In order to make the objects, technical solutions and advantages of the present invention more clear, the following detailed description with reference to the accompanying drawings The invention will be described in detail by way of examples. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Example 1

As shown in FIG. 1 , FIG. 2 and FIG. 3 , a coal grading screen 1 includes a casing 2 , a fabric board 14 , a plurality of geared motors 18 , and a drum screen shaft 3 and a screen screen shaft 4 , wherein The top of the casing 2 is provided with a feeding port 23, and the cloth board 14 is disposed obliquely below the feeding port 23, and a supporting frame 22 is respectively disposed on two sides of the casing 2, and the supporting frame 22 is fixedly mounted on the supporting frame 22 Bearing housing 17. The cloth board 14 is a pull-type cloth board made of wear-resistant and impact-resistant material, and its main function is cloth, and the replacement is convenient; when the cloth board 14 needs to be replaced due to wear, the worn cloth board can be worn. 14 Pull out directly from the casing 2, and then replace the new pull-type fabric board. The drum screen shaft 3 and the screen screen shaft 4 together constitute a screen surface of the coal grading screen 1. In the embodiment, the screen surface of the coal grading screen 1 is composed of a drum screen shaft 3 and seven The screen sieve shaft 4 is composed, and the angle of the sieve screen surface composed of the drum screen shaft 3 and the sieve screen shaft 4 is set to be 0 to 75°. A sieve surface observation hole 13 and a particle diameter observation hole 7 are further disposed on the casing 2, and the sieve surface of the coal grading sieve 1 can be sieved and conveyed through the sieve surface observation hole 13, and the qualified particle size coal material is observed. The case can be observed by the particle diameter observation hole 7.

The drum screen shaft 3 is made of a seamless steel pipe, and the specific structure thereof is as shown in FIG. 5, and a plurality of qualified screen slits 9 for leaking materials are provided on the drum screen shaft 3, and a guide is arranged inside the drum screen shaft 3. The material spiral 6 is composed of a positive guide screw 6.1 and a reverse guide screw 6.2 fixedly mounted on one side of the inside of the drum screen shaft 3, the reverse guide spiral 6.2 is fixedly mounted on the other side of the drum screen shaft 3, and the two ends of the drum screen shaft 3 are respectively provided with anti-blocking holes 10, and the two ends of the drum screen shaft 3 are respectively fixedly connected with one end of the detachable transmission shaft 16 The other end of the detachable transmission shaft 16 extends out of the casing 2 and is respectively connected to the corresponding bearing seat 17, and a sealing device 21 is arranged at the connection between the detachable transmission shaft 16 and the casing 2 to seal, as shown in FIG. Show. When the drum screen shaft 3 is rotated, the coal material entering the inside thereof can be discharged from the anti-blocking holes 10 at both ends of the drum screen shaft 3 under the pushing action of the guide screw 6.

The specific structure of the sieve screen shaft 4 is as shown in FIG. 6 and FIG. 7 , and includes a plurality of screen bars 8 , a flange piece 12 and a guide screw 6 , and the screen bars 8 are connected between the flange pieces 12 . The gap between the screen bars 8 forms a screen slit 9; the guide screw 6 is disposed in a cavity formed by the screen strip 8 and the flange piece 12, and the guide spiral 6 is guided by the positive guide screw 6.1 and the reverse guide The material spiral 6.2 is fixed, the positive guiding material screw 6.1 is fixedly mounted on one side of the screen meshing shaft 4, and the reverse guiding material spiral 6.2 is fixedly mounted on the other side inside the sieve meshing shaft 4, in the sieve screening screen The two ends of the shaft 4 are respectively provided with anti-blocking holes 10. The material of the screen strip 8 is not limited to the steel bar, and the shape of the screen strip 8 is not limited to a circular shape and a square shape, and the screen strip 8 connected to the flange piece 12 can be welded to the flange piece 12 to be a fixed screen strip. A gap is formed between the screen strips 8; a plurality of evenly distributed through holes may be formed in the flange piece 12, and the screen strip 8 is movably connected to the flange piece 12 through the through hole on the flange piece 12 to become active. The screen strips and the screen strips 8 form a gap; in addition, the screen strips 8 on the same screen screen screen shaft 4 may include two kinds of movable screen strips and fixed screen strips, and the movable screen strips and the fixed screen strips may be arranged in a staggered manner. When the screen screen shaft 4 is rotated, the coal material entering the inside thereof can be discharged from the anti-blocking holes 10 at both ends of the screen screen shaft 4 under the pushing action of the guide screw 6.

The two ends of the screen screen shaft 4 are also respectively connected to one end of the detachable transmission shaft 16. The other end of the detachable transmission shaft 16 extends out of the casing 2 and is respectively connected with the corresponding bearing seat 17, and is detachable. The connection between the drive shaft 16 and the casing 2 is provided with a sealing device 21 for sealing, as shown in FIG. The sprocket 20 is fixedly connected to the detachable transmission shaft 16 on the same side of the casing 2, and the sprocket 20 on the adjacent detachable transmission shaft 16 is connected and driven by the chain 19, and the reduction motor 18 is connected. The output shafts are respectively connected to the screen screen shaft 4 through the detachable transmission shaft 16, and the speed reduction motor 18 drives the chain 19 to rotate, thereby realizing the screening and transmission functions. The anti-blocking hole 10 on the screen screen shaft 4 can be configured such that the screen strip 8 extending outside the flange piece 12 adjacent to the detachable transmission shaft 16 is directly cut off to form an anti-blocking hole 10, as shown in the figure. 6 is shown.

The coal grading screen 1 shown in FIG. 1 is formed by mixing the drum screen shaft 3 and the screen screen shaft 4, respectively, between the upper portion of the drum screen shaft 3 and the screen screen shaft 4 and the inner wall of the casing 2, respectively. A tooth-shaped partitioning plate 5 as shown in FIG. 4 is provided, and a cutting channel 11 is formed between the tooth-shaped partitioning plate 5 and the inner wall of the casing 2, respectively, so that the sieve bar on the sieve screen shaft 4 can be 8 A plurality of pieces are cut off outside the tooth-shaped partitioning plate 5 to form an anti-blocking hole 10. The function of the tooth-shaped partitioning plate 5 is to separate the coal material on the screen surface from the drum screen shaft 3, the coal material guided by the guide screw 6 in the sieve screen shaft 4, and the coal material which is otherwise derived. The unqualified particle size coal caught in the screen 9 can also be pushed and dropped into the blanking channel 11 by the pushing of the guiding screw 6. A distribution plate 15 for distinguishing the sizes of different qualified materials is disposed at the lower end of the screen sieve shaft 3 and the sieve screen shaft 4, and the first connection with the blanking passage 11 is disposed on the casing 2 located on the left side of the distribution plate 15 The qualified particle size discharge port 24 is provided with a second qualified particle size discharge port 25 communicating with the discharge channel 11 on the casing 2 located on the right side of the material distribution plate 15, and the end of the discharge channel 11 is disposed at A defective particle size discharge port 26 on the casing 2. The sieve particle size of the coal grading screen 1 is continuously increased from the feed port 23 to the unqualified particle size discharge port 26, and is composed of a front sifter shaft 3 and a subsequent four sieve sifter shafts. 4 The sieve gap of the screen surface composed of a total of five sieve shafts is uniform, and the sieve gap of the screen surface composed of the three sieve screen shafts 4 remaining behind is larger than that of the first five sieve shafts. The sieve gap of the sieve surface is adapted to the screening of another coal of qualified particle size, and therefore, the coal sieve 1 can achieve fractional discharge. The grading discharge refers to changing the width of the sieve joint on the sieve shaft and passing the material on the premise that the gap width of the sieve screen slit is gradually increased from the feed port to the unqualified particle size discharge port. The plates are separated to achieve multiple levels of screening.

Example 2

The specific structure of the sieve screen shaft 4 is as shown in FIG. 8, and includes a fixed screen 27, a movable screen strip 28, a first supporting flange 30, and a first end movable flange 31 and a fixed flange piece. 35. The first supporting flange piece 30 may be disposed in a plurality of positions, and are respectively located between the two opposite first movable end flanges 31, on the outer side of the two first end movable flanges 31. A fixing flange 35 is respectively disposed, and the two fixing flanges 35 are respectively connected and fixed with the detachable transmission shaft 16, and the fixed screening rod 27 is a strip-shaped rod as shown in FIG. The blue sheet 35, the first end movable flange 31 and the first supporting flange 30 are fixedly connected, and the movable screen 28 is a round bar with a transition groove as shown in FIG. 10, and at the first A movable screen strip 28 is movably connected between the end movable flange 31 and the adjacent first support flange 30, and a movable screen strip is also movably connected between the adjacent two first support flanges 30. 28. The anti-blocking hole 10 is located between the first end movable flange 31 and the fixing flange piece 35, and the anti-blocking hole 10 may be located between the first end movable flange 31 and the fixed flange piece 35. The fixed screen strip 27 is formed by directly cutting a number of roots, which makes processing easier. Others are the same as in the first embodiment.

The structure of the first supporting flange 30 is as shown in FIG. 11 and FIG. 12, and the first supporting flange 30 is provided with a movable hole 32 and a fixing hole 33, and the movable hole 32 is used for The movable connection between the first support flange 30 and the movable screen strip 28 is used for a fixed connection between the first support flange 30 and the fixed screen strip 27. The structure of the first end movable flange 31 is as shown in FIG. 13 and FIG. 14 . The first end movable flange 31 is also provided with a movable hole 32 and a fixing hole 33. The movable hole 32 is provided. For a movable connection between the first end movable flange 31 and the movable screen bar 28, the fixing hole 33 is used for a fixed connection between the first end movable flange 31 and the fixed screen 27. The structure of the fixing flange 35 is as shown in FIG. 15 and FIG. 16 . The fixing flange 35 is provided with a connecting hole 36 for fixing the flange piece 35 and the fixing screen 27 . Fixed connection between. Specifically, the fixed screen 27 penetrates the fixing hole 33 of the first supporting flange 30 and is welded and fixed to the first supporting flange 30, and at the same time, the fixed screen 27 penetrates the first end movable flange. The fixing hole 33 of the piece 31 is welded and fixed to the first end movable flange 31, and the end of the fixing screen 27 is welded and fixed to the fixing flange 35 through the connecting hole 36, respectively. The movable screen strip 28 passes through the first supporting flange 30 and is slidably engaged with the movable hole 32 of the first supporting flange 30 through the transition groove portion thereon, and the movable screen strip 28 is respectively passed through the first The movable hole 32 on the one end movable flange 31 is movably connected to the first end movable flange 31 in a plugging manner.

The fixed screen strips 27 and the movable screen strips 28 may be arranged in a staggered manner to form a staggered movable screen screen shaft 4, and a plurality of regularly arranged convex tapered teeth 29 may be disposed on the outer surface of the movable screen strip 28, Also, the tapered teeth 29 on the adjacent movable screen bars 28 are staggered between each other by providing a taper on the outer surface of the movable screen strip 28. The teeth 29 can effectively pulverize the sheet material between the adjacent movable screen bars 28 into a granular material, so that the problem of the screening of the bulk materials such as coal can be well eliminated.

Example 3

The specific structure of the sieve screen shaft 4 is as shown in FIG. 17, and includes a fixed screen 27, a movable screen 28, a second supporting flange 37, and a second end movable flange 38 and a fixed flange. 35. The second supporting flange piece 37 may be disposed in plurality and located between the two opposite second end movable flanges 38 on the outer side of the two second end movable flanges 38. A fixing flange 35 is respectively arranged, and the two fixing flanges 35 are respectively connected and fixed to the detachable transmission shaft 16 , and the fixed screen strip 27 is fixedly connected to the fixing flange piece 35 and the adjacent second end portion. Between the movable flanges 38, and between the second end movable flange 38 and the adjacent second support flange 37, a movable screen bar 28 is movably connected to the adjacent two second supports. A movable screen strip 28 is also movably connected between the flange pieces 37. The anti-blocking hole 10 is located between the second end movable flange 38 and the fixing flange 35, and the anti-blocking hole 10 may be located between the second end movable flange 38 and the fixing flange 35 The fixed screen strip 27 is formed by directly cutting a plurality of roots, or may be formed directly by reducing the number of mountings of the fixed screen strips 27 in the space between the second end movable flange 38 and the fixed flange piece 35. Others are the same as in the first embodiment and the second embodiment.

The structure of the second supporting flange 37 is as shown in FIG. 18 and FIG. 19, and a movable hole 32 is formed in the second supporting flange 37, and the movable hole 32 is used for the second supporting flange. An active connection between the sheet 37 and the movable screen strip 28. The structure of the second end movable flange 38 is as shown in FIG. 20 and FIG. 21, and a stepped trapezoidal hole 34 is formed in the second end movable flange 38, and the trapezoidal hole 34 is used for the first The two ends of the movable flange 38 are respectively connected to the fixed sieve 27 and the movable sieve strip 28. As shown in FIG. 21, the trapezoidal holes 34 may be formed by abutting the movable holes 32 and the fixing holes 33 having different radii, and the center lines of the movable holes 32 and the fixing holes 33 coincide with each other, and the movable holes 32 are used for The second end is a movable connection between the movable flange 38 and the movable screen bar 28 for a fixed connection between the second end movable flange 38 and the fixed screen 27. In the screen sieve shaft 4 of this structure, the main screening portions are all composed of the movable screen bars 28, and the ends of the same trapezoidal holes 34 on the second end movable flange 38 can be simultaneously connected to the fixed screen bars 27 And movable screen bars 28.

It should be noted that by using the movable sieve strip 28 in the sieve screen shaft 4, the sieve joint in the sieve sieve shaft 4 can be made into a movable sieve joint, and therefore, the coal sieve sieve 1 is used to sieve high water slime. When it is not easy to block the screen joint, the problem of sieving high-water slime by the coal grading screen 1 is effectively solved, and the grading efficiency and the screening effect are ensured.

The working principle (screening process) of the coal grading screen 1 of the present invention is as follows:

Assume that the coal (coal gangue) is 800t / h, the feed particle size is 0 ~ 200mm, the current working conditions need to filter the two sizes of coal: 0 ~ 10mm and 10 ~ 30mm. To this end, a plurality of 10 mm sieve slits 9 are provided on the drum screen shaft 3, Each of the sieve screen shafts 4 is also provided with a plurality of 10 mm sieve slits 9, the first qualified discharge port 24 has a particle diameter of not more than 10 mm, and the second qualified discharge port 25 has a particle diameter of 10 to 30 mm. The length and diameter of the sieve shaft 3 and the sieve screen shaft 4 are the same.

When the coal material enters the machine body from the feed port 23 at the top of the casing 2 at a flow rate of 800t/h, it falls directly and falls onto the pull-type cloth board 14, and breaks the columnar structure of the coal material through the cloth board 14 to make the coal material appear The elliptical column falls to the screen surface composed of the drum screen shaft 3 and the screen screen shaft 4, wherein the coal material dropped through the cloth sheet 14 first falls onto the drum screen shaft 3 and once again breaks the elliptical structure, and then the coal material It is screened, clothed, and conveyed on a sieve surface composed of 7 sieve screen shafts 4. The screen screen shaft 4 is connected to the speed reduction motor 18, and the screen screen shaft 4 and the drum screen shaft 3 are driven to rotate clockwise by the speed reduction motor 18, and the length, diameter and rotation of the screen screen shaft 3 and the sieve screen shaft 4 are rotated. The number is the same, so that the coal material can be evenly diffused to the entire screen surface, and a wave type conveying and sieving is formed on the screen surface, wherein the coal material having a particle diameter of less than or equal to 10 mm falls into the drum screen shaft 3, the sieve In the sieve shaft 4, the coal material having a particle diameter of less than 10 mm can be directly passed through the sieve 9 through the centrifugal force generated by the high speed rotation of the drum screen shaft 3 and the sieve screen shaft 4, and finally discharged through the first qualified discharge port 24. The casing 2, the coal material having a particle diameter equal to or slightly larger than 10 mm is pushed and transported by the guide screw 6, and finally discharged from the anti-blocking hole 10 at both ends of the drum screen shaft 3 and the sieve screen shaft 4 and enters the tooth-shaped partition plate 5 In the blanking passage 11 between the casing 2 and the casing 6 , the coal material stuck in the screen 9 can also be discharged from the anti-blocking hole 10 and finally discharged through the first qualified outlet 24 to the casing 2 . , the sieving of coal materials with a particle size of 0 to 10 mm is completed; and the coal materials with a particle size of 10 to 30 mm are sieved through the sieve screen shaft 4 and then dropped to the next. In the channel 11, the casing 2 is then discharged from the second qualified discharge port 25 of 10 to 30 mm to complete the screening of the coal material of 10 to 30 mm particle size. Finally, the coal material of 30 to 200 mm particle size is out of the unqualified particle size. The spout 26 exits the casing 2.

The sieve surface in the above-mentioned coal grading sieve 1 may be entirely composed of the drum screen shaft 3, or all of the sieve screen shaft 4, or may be mixed with the screen sieve shaft 3 and the sieve screen shaft 4 in the coal grading screen. In the first embodiment, the geared motor 18 can drive one or several drum screen shafts 3 and/or screen screen shafts 4 according to working conditions. The shape of the drum screen shaft 3 and/or the screen screen shaft 4 may be circular, polygonal or the like, and the shape of the anti-blocking hole 10 is not limited to a rectangular shape. Since the guide screw 6 in the screen screen shaft 3 and the screen screen shaft 4 includes the positive guide screw 6.1 and the reverse guide screw 6.2 forward and reverse angle spirals, it is ensured that the drum screen shaft 3 and the screen screen shaft 4 rotate. The coal material is pushed to the anti-blocking holes 10 at both ends of the screen shaft through the positive guide screw 6.1 and the reverse guide screw 6.2 to be discharged. The guide spiral 6 can also be replaced by a guide plate, and the guide plate is welded in the forward and reverse directions in the drum screen shaft 3 and the sieve screen shaft 4, and the function is the same as the guide spiral.

Since the drum screen shaft 3 and the screen screen shaft 4 are connected by the detachable drive shaft 16, when the worn drum screen shaft 3 and the screen screen shaft 4 need to be replaced, only the drum screen shaft 3 and the screen rod are required. Screen shaft 4 and detachable drive shaft 16 separate from each other, and then replace with a new drum screen shaft 3, sieve screen shaft 4.

The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention. It should be noted that any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included. It is within the scope of the invention.

Claims

The coal grading screen comprises a casing (2), a cloth board (14) and a drum screen shaft (3) and a screen sieve shaft (4), and the cloth board (14) is obliquely disposed on the casing (2) Below the feed port (23), the drum screen shaft (3) and the screen screen shaft (4) together form a screen surface of the grading screen, characterized in that the drum screen shaft (3) and the sieve screen shaft ( 4) A guide spiral (6) is arranged inside, and the guide spiral (6) is composed of a positive guide spiral (6.1) and a reverse guide spiral (6.2), and the positive guide spiral (6.1) is fixedly installed. On the side inside the drum screen shaft (3) or the screen screen shaft (4), the reverse guide screw (6.2) is fixedly mounted to the inside of the drum screen shaft (3) or the screen screen shaft (4). On the side, anti-blocking holes (10) are respectively disposed at both ends of the drum screen shaft (3) and the screen screen shaft (4).
The coal grading screen according to claim 1, characterized in that the screen screen shaft (3) is provided with a screen slit (9).
The coal grading screen according to claim 1 or 2, characterized in that the sieve screen shaft (4) comprises a plurality of screen bars (8) and a flange piece (12), the screen bars (8) Connected between the flanges (12) and a gap is formed between the screen bars (8).
The coal grading screen according to claim 3, characterized in that the sieve bar (8) on the sieve screen shaft (4) comprises a movable sieve strip and a fixed sieve strip, and the movable sieve strip and the fixed sieve strip Staggered.
The sieving screen for coal according to claim 1, characterized in that the sieve screen shaft (4) comprises a fixed screen (27), a movable screen (28), and a first supporting flange (30). And a first end movable flange (31) and a fixed flange piece (35), the first support flange piece (30) being located at two opposite first movable end flanges (31) A fixing flange piece (35) is respectively disposed outside the two first end movable flanges (31), and the fixed screen strips (27) are respectively movable with the fixing flange piece (35) and the first end portion The flange piece (31) is fixedly coupled to the first support flange piece (30), and the movable screen strip (28) is movably connected to the first end movable flange piece (31) and the adjacent first support flange Between the sheets (30), an anti-blocking hole (10) is provided between the first end movable flange (31) and the fixed flange piece (35).
The coal grading screen according to claim 1, characterized in that the sieve screen shaft (4) comprises a fixed screen (27), a movable screen (28) and a second supporting flange (37). And a second end movable flange (38) and a fixed flange piece (35), the second support flange piece (37) being located at two opposite second movable end flanges (38) A fixing flange (35) is respectively disposed outside the two second end movable flanges (38), and the fixed screen (27) is fixedly connected to the fixing flange (35) and the adjacent one. Between the two end movable flanges (38), between the second end movable flange (38) and the adjacent second support flange (37) The movable screen strip (28) is provided with an anti-blocking hole (10) between the second end movable flange (38) and the fixed flange piece (35).
The grading screen for coal according to claim 5 or 6, wherein in the sieve screen shaft (4), a plurality of convex tapered teeth are arranged on the outer surface of the movable screen (28) ( 29), and the tapered teeth (29) on the adjacent movable screen bars (28) are staggered.
The grading screen for coal according to claim 1 or 2, characterized in that the drum screen shaft (3) and the upper portion of the two ends of the sieve screen shaft (4) are provided with teeth between the inner walls of the casing (2). Shaped partition plate (5).
The coal grading screen according to claim 8, characterized in that the screen strip (8) on the screen screen shaft (4) is cut off outside the tooth-shaped partition plate (5) to form an anti-blocking hole ( 10).
The coal grading screen according to claim 1, wherein the fabric board (14) is a pull-type cloth board.
The grading screen for coal according to claim 1, characterized in that the angle of the screen surface composed of the drum screen shaft (3) and the sieve screen shaft (4) is set to be 0 to 75°.