Wear-resistant bottom lining plate of edge runner mill
By laying segmented and spliced silicon carbide plate lining components on the bottom surface of the roller mill hopper, the problem of insufficient wear resistance of the roller mill bottom lining plate is solved, the replacement cycle is extended and the cost is reduced, and the stability of use and production efficiency are improved.
Patent Information
- Application Number
- CN202423152499.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-20
- Publication Date
- 2026-01-02
- Estimated Expiration
- 2034-12-20
AI Technical Summary
When wear-resistant metal plates are used as the bottom lining of existing roller mill mixers, their wear resistance is limited, resulting in a short service life. Frequent replacements increase maintenance costs and affect production efficiency.
The outer ring liner assembly, the middle ring liner assembly, and the inner ring liner assembly are laid sequentially from the outside to the inside on the bottom surface of the roller mill hopper body. Silicon carbide plates are used and are assembled into an integral bottom liner structure by segment splicing. They are fixed with an adhesive layer to facilitate the individual replacement of worn parts.
This extends the service life and replacement cycle of the bottom liner, reduces replacement costs, and improves operational stability and production efficiency.
Smart Images
Figure CN223747680U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the auxiliary assembly field of wheel mill, concretely relates to a wheel mill wear -resisting bottom lining plate. BACKGROUND
[0002] Wheel mill mixer is the use roller's gravity, crush and crush material's rough grinding machinery, and the crushing mechanism is roller and mill disc. Wheel mill mixer in work, the roller is guided by the guide rail, according to the material height realizes up and down lifting movement, the roller is always to material and is pressed, and the side scraper and the middle fixed bracket board send the raw material dispersed around the disc to the roller pressing range, and the stirring rotor is used to shovel the material after being pressed to the roller again, so that the material in the disc is mixed evenly after the full stirring and pressing, and when the mixing reaches the requirement, the discharge door is lifted, and the swing cylinder drives the swing bracket to rotate to the discharge position, so that the material is discharged from the rotating disc center. Wheel mill mixer is suitable for crushing silica stone and clay and the like below medium hardness, or for mixing materials, so that the wheel mill mixer is widely used in the preparation process of refractory bricks.
[0003] Specific to the use process of wheel mill mixer, in order to avoid the direct contact between the roller and the inner bottom surface of the wheel mill mixer and accelerate the wear of the inner bottom surface of the wheel mill mixer, a bottom lining plate is usually laid on the inner bottom surface of the wheel mill mixer to achieve good wear resistance. However, the inner bottom surface of the current wheel mill mixer usually selects a metal plate made of wear-resistant metal material when laying the bottom lining plate, and the wear resistance of the wear-resistant metal plate itself is limited, so that the service life of the bottom lining plate is short, which not only needs frequent replacement and increases the maintenance cost, but also interrupts the production and affects the production efficiency. UTILITY MODEL CONTENTS
[0004] The utility model discloses a wheel mill wear -resisting bottom lining plate, and the inner bottom surface of the wheel mill bin body is sequentially laid with outer ring lining plate assembly, middle ring lining plate assembly and inner ring lining plate assembly from outside to inside, and the outer ring lining plate assembly is sleeved on the inner periphery of the wheel mill bin body, the middle ring lining plate assembly is sleeved on the inner periphery of the outer ring lining plate assembly, and the inner ring lining plate assembly is sleeved on the inner periphery of the middle ring lining plate assembly, so that the outer ring lining plate assembly, the middle ring lining plate assembly and the inner ring lining plate assembly can form an integral bottom lining plate structure on the inner bottom surface of the wheel mill bin body, and the combination mode of the integral bottom lining plate structure is simple and easy to realize.
[0005] To achieve the above object, the utility model provides the following technical scheme:
[0006] The utility model provides a kind of wheel mill wear-resistant bottom lining, including wheel mill stock bin body, the inner bottom surface of wheel mill stock bin body is sequentially laid with outer ring lining plate assembly, middle ring lining plate assembly and inner ring lining plate assembly from outside to inside, while the outer ring lining plate assembly is set in the inner perimeter of the wheel mill stock bin body, the middle ring lining plate assembly is set in the inner perimeter of the outer ring lining plate assembly, the inner ring lining plate assembly is set in the inner perimeter of the middle ring lining plate assembly, to bucket cover the outer ring lining plate assembly, the middle ring lining plate assembly and the inner ring lining plate assembly in the inner bottom surface of the wheel mill stock bin body constitute the bottom lining structure of whole.
[0007] As preferred, the outer ring lining plate assembly is specifically annular whole circle style constituted by a plurality of outer peripheral lining plates circumferentially connected head to tail.
[0008] As preferred, the outer peripheral lining plate is all arc plate, the number of outer peripheral lining plate is 16 and is circumferentially uniformly arranged, and the outer peripheral outer arc edge of outer peripheral lining plate is between 18.5 ° and 22.5 °, the radius range of the outer peripheral outer arc edge of outer peripheral lining plate is between 1373 mm and 1373.5 mm, the radius range of the outer peripheral inner arc edge of outer peripheral lining plate is between 1101.5 mm and 1102 mm.
[0009] As preferred, the middle ring lining plate assembly is specifically annular whole circle style constituted by a plurality of middle part lining plates circumferentially connected head to tail.
[0010] As preferred, the middle part lining plate is all arc plate, the number of middle part lining plate is 18 and is circumferentially uniformly arranged, and the middle part outer arc edge of middle part lining plate is between 16 ° and 20 °, the radius range of the middle part outer arc edge of middle part lining plate is between 1098 mm and 1098.5 mm, the radius range of the middle part inner arc edge of middle part lining plate is between 551.5 mm and 552 mm.
[0011] As preferred, the inner ring lining plate assembly is specifically annular whole circle style constituted by a plurality of inner peripheral lining plates circumferentially connected head to tail.
[0012] As preferred, the inner peripheral lining plate is all arc plate, the number of inner peripheral lining plate is 8 and is circumferentially uniformly arranged, and the inner peripheral outer arc edge of inner peripheral lining plate is between 41 ° and 45 °, the radius range of the inner peripheral outer arc edge of inner peripheral lining plate is between 548 mm and 548.5 mm, the radius range of the inner peripheral inner arc edge of inner peripheral lining plate is between 341.5 mm and 342 mm.
[0013] Preferably, the outer peripheral lining plate, the middle lining plate and the inner peripheral lining plate are all silicon carbide plates, and the outer peripheral lining plate, the middle lining plate and the inner peripheral lining plate are combined and fixed with the inner bottom surface of the roller mill bin body by means of a layer of adhesive.
[0014] Preferably, the inner circle formed by the plurality of inner peripheral lining plates after being enclosed constitutes a discharging channel, and the discharging channel is vertically opposite to the material falling channel in the middle of the inner bottom surface of the roller mill bin body.
[0015] In the process of arranging the overall bottom lining plate structure on the inner bottom surface of the roller mill bin body, the outer ring lining plate assembly, the middle ring lining plate assembly and the inner ring lining plate assembly are sequentially arranged from the outer to the inner on the inner bottom surface of the roller mill bin body, the outer ring lining plate assembly is sleeved on the inner periphery of the roller mill bin body, the middle ring lining plate assembly is sleeved on the inner periphery of the outer ring lining plate assembly, and the inner ring lining plate assembly is sleeved on the inner periphery of the middle ring lining plate assembly. In this way, the outer ring lining plate assembly, the middle ring lining plate assembly and the inner ring lining plate assembly can form an overall bottom lining plate structure on the inner bottom surface of the roller mill bin body. The combination of the overall bottom lining plate structure is simple and easy to implement, and the combination and arrangement of the overall bottom lining plate structure on the inner bottom surface of the roller mill bin body can be quickly completed. Since the outer ring lining plate assembly is an annular whole formed by a plurality of outer peripheral lining plates connected in a circumferential direction, the middle ring lining plate assembly is an annular whole formed by a plurality of middle lining plates connected in a circumferential direction, and the inner ring lining plate assembly is an annular whole formed by a plurality of inner peripheral lining plates connected in a circumferential direction, the outer ring lining plate assembly, the middle ring lining plate assembly and the inner ring lining plate assembly are combined by means of block splicing, which facilitates subsequent individual replacement and maintenance of each of the outer peripheral lining plate, the middle lining plate and the inner peripheral lining plate. The outer peripheral lining plate, the middle lining plate and the inner peripheral lining plate can be replaced according to the actual degree of wear, which helps to prolong the replacement cycle and reduce the replacement cost. Since the outer peripheral lining plate, the middle lining plate and the inner peripheral lining plate are all arc-shaped silicon carbide plates, they have good wear resistance. The outer peripheral lining plate, the middle lining plate and the inner peripheral lining plate are combined and fixed with the inner bottom surface of the roller mill bin body by means of a layer of adhesive, which has high reliability and stable solidification after combination and fixation, helps to improve the stability of the outer peripheral lining plate, the middle lining plate and the inner peripheral lining plate on the inner bottom surface of the roller mill bin body, and is conducive to further prolonging the replacement cycle and reducing the replacement cost.
[0016] The beneficial effects are as follows: 1. In this utility model, an outer ring liner assembly, a middle ring liner assembly, and an inner ring liner assembly are laid sequentially from the outside to the inside on the inner bottom surface of the roller mill hopper body. At the same time, the outer ring liner assembly is fitted on the inner circumference of the roller mill hopper body, the middle ring liner assembly is fitted on the inner circumference of the outer ring liner assembly, and the inner ring liner assembly is fitted on the inner circumference of the middle ring liner assembly. In this way, the outer ring liner assembly, the middle ring liner assembly, and the inner ring liner assembly of the bucket cover can form an integral bottom liner structure on the inner bottom surface of the roller mill hopper body. The combination method of the integral bottom liner structure is simple and easy to realize, which facilitates the quick completion of the combination and layout of the integral bottom liner structure on the inner bottom surface of the roller mill hopper body.
[0017] 2. The outer ring liner assembly is a complete ring formed by connecting multiple outer circumferential liner plates from end to end. The middle ring liner assembly is a complete ring formed by connecting multiple middle liner plates from end to end. The inner ring liner assembly is a complete ring formed by connecting multiple inner circumferential liner plates from end to end. Since the outer ring liner assembly, middle ring liner assembly, and inner ring liner assembly are all assembled in a modular way, the modular design facilitates the individual replacement and maintenance of each outer circumferential liner, middle liner, and inner circumferential liner plate. This allows for flexible replacement of the corresponding outer circumferential liner, middle liner, and inner circumferential liner plates according to the actual wear level, which helps to extend the service life and reduce replacement costs.
[0018] 3. The outer, middle, and inner circumferential liners are all arc-shaped silicon carbide blocks, which gives them significant wear resistance. Furthermore, the outer, middle, and inner circumferential liners are bonded and fixed to the inner bottom surface of the roller mill hopper body using an adhesive layer applied to the lid. This bonding and fixing method ensures high reliability and stable curing, improving the stability of the outer, middle, and inner circumferential liners within the inner bottom surface of the roller mill hopper body. This further extends the service life and reduces replacement costs. Attached Figure Description
[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0020] Figure 1 This is a top view of the entire utility model;
[0021] Figure 2 This is a utility model Figure 1 Schematic diagram of the outer lining plate;
[0022] Figure 3 is the utility model Figure 2 A place local enlarged view of
[0023] Figure 4 is the utility model Figure 1 The middle lining plate schematic view of
[0024] Figure 5 is the utility model Figure 1 The inner circumferential lining plate schematic view of
[0025] Figure 6 is the utility model Figure 1 The front view schematic view of
[0026] The figure mark is explained as follows:
[0027] 1, the outer circle lining plate assembly;101, the outer circumferential outer arc edge;102, the outer circumferential lining plate;103, the outer circumferential inner arc edge;2, the middle circle lining plate assembly;201, the middle part outer arc edge;202, the middle lining plate;203, the middle part inner arc edge;3, the inner circle lining plate assembly;301, the inner circumferential lining plate;302, the inner circumferential outer arc edge;303, the inner circumferential inner arc edge;4, the material discharging channel;5, the wheel mill stock bin body;501, the material discharging channel;6, the adhesive layer. Specific implementation
[0028] To make the utility model's purpose, technical scheme and advantage more clear, the technical scheme of the utility model will be described in detail below. Obviously, the described embodiment is only a part of the embodiment of the utility model, not all the embodiment. Based on the embodiment in the utility model, all other implementation manners obtained by the person skilled in the art without making the creative labor, belong to the range of the utility model's protection.
[0029] Referring to Figures 1-6The utility model provides a kind of wheel mill wear-resistant bottom lining, including wheel mill stock bin body 5, the inner bottom surface of wheel mill stock bin body 5 is sequentially laid with outer ring lining plate assembly 1, middle ring lining plate assembly 2 and inner ring lining plate assembly 3 from outside to inside, while outer ring lining plate assembly 1 is sleeved in the inner periphery of wheel mill stock bin body 5, middle ring lining plate assembly 2 is sleeved in the inner periphery of outer ring lining plate assembly 1, inner ring lining plate assembly 3 is sleeved in the inner periphery of middle ring lining plate assembly 2, to bucket cover outer ring lining plate assembly 1, middle ring lining plate assembly 2 and inner ring lining plate assembly 3 form the bottom lining structure of whole in the inner bottom surface of wheel mill stock bin body 5, specifically, outer ring lining plate assembly 1 is specifically by the annular whole circle style that a plurality of outer peripheral lining plates 102 circumferentially successively, middle ring lining plate assembly 2 is specifically by the annular whole circle style that a plurality of middle lining plates 202 circumferentially successively, inner ring lining plate assembly 3 is specifically by the annular whole circle style that a plurality of inner peripheral lining plates 301 circumferentially successively, the purpose of such arrangement is, first bucket cover outer ring lining plate assembly 1, middle ring lining plate assembly 2 and inner ring lining plate assembly 3 can form the bottom lining structure of whole in the inner bottom surface of wheel mill stock bin body 5, the combination mode of whole bottom lining structure is simple and easy to realize, it is convenient to complete the combination layout of whole bottom lining structure in the inner bottom surface of wheel mill stock bin body 5, simultaneously since outer ring lining plate assembly 1, middle ring lining plate assembly 2 and inner ring lining plate assembly 3 all adopt the way of block splicing combination, then through the design of splicing type can be conveniently subsequently replaced maintenance to each outer peripheral lining plate 102, middle lining plate 202 and inner peripheral lining plate 301 respectively, it is convenient to replace outer peripheral lining plate 102, middle lining plate 202 and inner peripheral lining plate 301 of corresponding position flexibly according to actual wear degree.
[0030] Referring to Figures 2-5As shown, the outer ring lining plate assembly 1, the middle ring lining plate assembly 2 and the inner ring lining plate assembly 3 are respectively optimized as follows. As to the outer ring lining plate assembly 1, the outer peripheral lining plates 102 are all arc-shaped plates, the number of the outer peripheral lining plates 102 is 16 and the outer peripheral lining plates 102 are circumferentially and uniformly arranged, and the arc angle range of the outer peripheral outer arc edges 101 of the outer peripheral lining plates 102 is between 18.5° and 22.5°, the radius range of the outer peripheral outer arc edges 101 of the outer peripheral lining plates 102 is between 1373mm and 1373.5mm, and the radius range of the outer peripheral inner arc edges 103 of the outer peripheral lining plates 102 is between 1101.5mm and 1102mm. In this way, the design style of the outer peripheral lining plates 102 can meet the use needs and can be batch processed and manufactured. As to the middle ring lining plate assembly 2, the middle lining plates 202 are all arc-shaped plates, the number of the middle lining plates 202 is 18 and the middle lining plates 202 are circumferentially and uniformly arranged, and the arc angle range of the middle outer arc edges 201 of the middle lining plates 202 is between 16° and 20°, the radius range of the middle outer arc edges 201 of the middle lining plates 202 is between 1098mm and 1098.5mm, and the radius range of the middle inner arc edges 203 of the middle lining plates 202 is between 551.5mm and 552mm. In this way, the design style of the middle lining plates 202 can meet the use needs and can be batch processed and manufactured. The inner peripheral lining plates 301 are all arc-shaped plates, the number of the inner peripheral lining plates 301 is 8 and the inner peripheral lining plates 301 are circumferentially and uniformly arranged, and the arc angle range of the inner peripheral outer arc edges 302 of the inner peripheral lining plates 301 is between 41° and 45°, the radius range of the inner peripheral outer arc edges 302 of the inner peripheral lining plates 301 is between 548mm and 548.5mm, and the radius range of the inner peripheral inner arc edges 303 of the inner peripheral lining plates 301 is between 341.5mm and 342mm. In this way, the design style of the inner peripheral lining plates 301 can meet the use needs and can be batch processed and manufactured.
[0031] Referring to Figure 6As shown, further optional, the outer peripheral lining plate 102, the middle lining plate 202 and the inner peripheral lining plate 301 are all silicon carbide plates, which are combined and fixed with the inner bottom surface of the wheel mill bin body 5 in the way of coating and bonding agent layer 6, preferably the bonding agent layer 6 can be selected as dolomite glue, so as to ensure that the reliability after combination and fixation is high and the solidification is stable, which is helpful to improve the use stability of the outer peripheral lining plate 102, the middle lining plate 202 and the inner peripheral lining plate 301 on the inner bottom surface of the wheel mill bin body 5, and is conducive to further prolonging the use and replacement cycle and reducing the replacement cost. At the same time, the inner circle formed by the plurality of inner peripheral lining plates 301 is the discharge channel 4, and the discharge channel 4 is vertically opposite to the material falling channel 501 in the middle of the inner bottom surface of the wheel mill bin body 5, which is convenient to ensure that the refractory raw materials after rolling and mixing can be smoothly discharged outward through the discharge channel 4 and the material falling channel 501 in turn.
[0032] With the above structure, specifically in the process of arranging the overall bottom lining plate structure on the inner bottom surface of the roller mill bin body 5, since the outer ring lining plate assembly 1, the middle ring lining plate assembly 2 and the inner ring lining plate assembly 3 are sequentially arranged on the inner bottom surface of the roller mill bin body 5 from outside to inside, and the outer ring lining plate assembly 1 is sleeved on the inner periphery of the roller mill bin body 5, the middle ring lining plate assembly 2 is sleeved on the inner periphery of the outer ring lining plate assembly 1, and the inner ring lining plate assembly 3 is sleeved on the inner periphery of the middle ring lining plate assembly 2, the outer ring lining plate assembly 1, the middle ring lining plate assembly 2 and the inner ring lining plate assembly 3 can form the overall bottom lining plate structure on the inner bottom surface of the roller mill bin body 5. The combination mode of the overall bottom lining plate structure is simple and easy to implement, and the combination and arrangement of the overall bottom lining plate structure on the inner bottom surface of the roller mill bin body 5 can be quickly completed. Since the outer ring lining plate assembly 1 is an annular whole ring type formed by circumferentially connecting a plurality of outer peripheral lining plates 102 end to end, the middle ring lining plate assembly 2 is an annular whole ring type formed by circumferentially connecting a plurality of middle lining plates 202 end to end, and the inner ring lining plate assembly 3 is an annular whole ring type formed by circumferentially connecting a plurality of inner peripheral lining plates 301 end to end, and the outer ring lining plate assembly 1, the middle ring lining plate assembly 2 and the inner ring lining plate assembly 3 are combined by the block splicing mode, the subsequent individual replacement and maintenance of each outer peripheral lining plate 102, middle lining plate 202 and inner peripheral lining plate 301 can be facilitated by the splicing design, the corresponding outer peripheral lining plate 102, middle lining plate 202 and inner peripheral lining plate 301 can be replaced flexibly according to the actual wear degree, which is helpful to prolong the replacement cycle and reduce the replacement cost. Since the outer peripheral lining plate 102, the middle lining plate 202 and the inner peripheral lining plate 301 are all arc plate type silicon carbide blocks, the outer peripheral lining plate 102, the middle lining plate 202 and the inner peripheral lining plate 301 all have significant wear resistance, and the outer peripheral lining plate 102, the middle lining plate 202 and the inner peripheral lining plate 301 are combined and fixed with the inner bottom surface of the roller mill bin body 5 by the adhesive layer 6, which has high reliability and stable solidification after combination and fixation, and is helpful to improve the use stability of the outer peripheral lining plate 102, the middle lining plate 202 and the inner peripheral lining plate 301 on the inner bottom surface of the roller mill bin body 5, which is helpful to further prolong the replacement cycle and reduce the replacement cost.
[0033] The above is only a specific implementation manner of the present application, but the protection scope of the present application is not limited thereto, any skilled person in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.
Claims
1. A mill liner, comprising a mill bin body (5), characterized in that: The inner bottom surface of the roller mill bin body (5) is sequentially paved from outside to inside with an outer ring lining plate assembly (1), a middle ring lining plate assembly (2) and an inner ring lining plate assembly (3), and meanwhile, the outer ring lining plate assembly (1) is sleeved on the inner periphery of the roller mill bin body (5), the middle ring lining plate assembly (2) is sleeved on the inner periphery of the outer ring lining plate assembly (1), and the inner ring lining plate assembly (3) is sleeved on the inner periphery of the middle ring lining plate assembly (2), so as to cover the outer ring lining plate assembly (1), the middle ring lining plate assembly (2) and the inner ring lining plate assembly (3) on the inner bottom surface of the roller mill bin body (5) to form a bottom lining plate structure.
2. A mill liner as claimed in claim 1, wherein: The outer ring lining plate assembly (1) is specifically an annular whole-ring type formed by a plurality of outer peripheral lining plates (102) connected in series in the circumferential direction.
3. A mill liner as claimed in claim 2, wherein: The outer peripheral lining plates (102) are all arc-shaped plates, the number of the outer peripheral lining plates (102) is 16 and they are arranged in the circumferential direction in a uniform distribution, and the outer peripheral outer arc edge (101) of the outer peripheral lining plate (102) has an arc angle range of 18.5° to 22.5°, the radius range of the outer peripheral outer arc edge (101) of the outer peripheral lining plate (102) is 1373mm to 1373.5mm, and the radius range of the outer peripheral inner arc edge (103) of the outer peripheral lining plate (102) is 1101.5mm to 1102mm.
4. A mill liner as claimed in claim 2 or 3, wherein: The middle ring lining plate assembly (2) is specifically an annular whole-ring type formed by a plurality of middle lining plates (202) connected in series in the circumferential direction.
5. A mill liner as claimed in claim 4, wherein: The middle lining plates (202) are all arc-shaped plates, the number of the middle lining plates (202) is 18 and they are arranged in the circumferential direction in a uniform distribution, and the middle outer arc edge (201) of the middle lining plate (202) has an arc angle range of 16° to 20°, the radius range of the middle outer arc edge (201) of the middle lining plate (202) is 1098mm to 1098.5mm, and the radius range of the middle inner arc edge (203) of the middle lining plate (202) is 551.5mm to 552mm.
6. A mill liner as claimed in claim 5, wherein: The inner ring lining plate assembly (3) is specifically an annular whole-ring type formed by a plurality of inner peripheral lining plates (301) connected in series in the circumferential direction.
7. A mill liner as claimed in claim 6, wherein: The inner peripheral lining plates (301) are all arc-shaped plates, the number of the inner peripheral lining plates (301) is 8 and they are arranged in the circumferential direction in a uniform distribution, and the inner peripheral outer arc edge (302) of the inner peripheral lining plate (301) has an arc angle range of 41° to 45°, the radius range of the inner peripheral outer arc edge (302) of the inner peripheral lining plate (301) is 548mm to 548.5mm, and the radius range of the inner peripheral inner arc edge (303) of the inner peripheral lining plate (301) is 341.5mm to 342mm.
8. A mill liner as claimed in claim 6 or 7, wherein: The outer peripheral lining plate (102), the middle lining plate (202) and the inner peripheral lining plate (301) are all silicon carbide plates, and the outer peripheral lining plate (102), the middle lining plate (202) and the inner peripheral lining plate (301) are combined and fixed with the inner bottom surface of the roller mill bin body (5) in a manner of covering and smearing an adhesive layer (6).
9. A mill liner as claimed in claim 8, wherein: The inner circle formed after the inner peripheral lining plates (301) are enclosed constitutes a discharge channel (4), and the discharge channel (4) is vertically opposite to a material falling channel (501) in the middle of the inner bottom surface of the roller mill bin body (5).