RU2676118C2 - Apparatus and method for imparting selected topographies to aluminium sheet metal and applications there for - Google Patents

Abstract

FIELD: metal rolling.SUBSTANCE: invention relates to the field of rolling an aluminium sheet and manufacturing therefrom a container for crushed material. Method comprises forming, from an aluminium sheet, at least one surface in contact with the crushed material, forming an interior space. Increase in the homogeneity of the sheet surface is ensured by that the aluminium sheet is subjected to forming, the static friction coefficient of which, when in contact with the crushed material, is 0.62-0.79, obtained by rolling a working roll, the surface of which is covered 50-100% with depressions without faces, with a central region recessed relative to the average height of said surface, and a projecting smooth peripheral projection having a higher height at its apex than the average height of said surface.EFFECT: slippery sheet material can be used to make tanks, bins, pipelines and guide structures to facilitate the storage and movement of the flow of granular material.20 cl, 21 dwg

Description

Cross reference to related applications

This application is a partly continuing application of US application No. 13/892028 with the name "Device and method for giving selected topographies to aluminum sheet", filed May 10, 2013, which is partly continuing application of US application No. 13/673468 with the name "Device and method for of Giving Selected Topographies to an Aluminum Sheet, filed November 9, 2012, which claims the priority of provisional application US No. 61/558504 titled "Device and Method for Giving Selected Topographies to an Aluminum Sheet, filed November 11, 2 011 years. The disclosure of each of the above applications is fully incorporated herein by reference in all respects.

Technical field

The present invention relates to rolled sheet metal and surface treatment, and more particularly, to methods and apparatus for producing desired surface textures having corresponding frictional and optical properties, such as an isotropic surface on an aluminum sheet.

State of the art

Currently, aluminum sheet manufacturers often use a cold rolling mill to produce a sheet with the desired thickness, width and surface. To obtain the desired surfaces can also be used training mills with small degrees of reduction (<10%). The surface of the cylindrical rolls (work rolls) through which the aluminum sheet passes can be prepared for rolling by grinding with an abrasive grinding wheel or tape. Grinding gives the surface of the roll anisotropic in appearance and in relation to frictional properties due to traces of grinding (texture), which are then transmitted / communicated to the sheet, which is rolled using a sanded work roll. The anisotropic appearance of a sheet rolled using polished work rolls is visually noticeable and can often be observed through paint coatings applied to sheet material or products made from sheet material, such as a car body panel.

Embossing machines are also used to give sheet metal a given surface topography, for example, to obtain undirected topographies. Sheet processing in the embossing machine is carried out after the rolling process and after the sheet has been compressed in thickness to the required dimensions, which are approximately equal to the final dimensions of the sheet. Embossing machines are intended only to convey the texture of the surface, and not to have a significant effect on the dimensions of the sheet, and therefore are used for sheets that have already been rolled using work rolls of a rolling mill. Embossing a sheet in an embossing machine is an additional step beyond rolling, implying an additional device, loading and unloading operations, as well as managing a wide variety of types of rolls compared to conventional rolling mills.

SUMMARY OF THE INVENTION

The present invention relates to a method for manufacturing a device for handling material, having at least one surface in contact with the material, comprising the steps of:

to obtain an aluminum sheet that has been rolled using a work roll having a surface that is 50% to 100% coated with recesses that do not have faces and have a recessed central region relative to the average surface height and a protruding smooth peripheral protrusion having a higher height at its apex, than the average surface height, while the aluminum sheet has a static coefficient of friction with at least one material in the range from 0.62 to 0.79; and

forming from an aluminum sheet at least one surface in contact with the material.

In another embodiment, the recesses have a diameter in the range of 150 μm to 400 μm and a depth relative to the top of the peripheral protrusion in the range of 6 ± 2.0 μm.

In another embodiment, the device for handling material is a hopper with an internal space for storing material, while the surface in contact with the material forms at least a portion of the surface forming the internal space.

In another embodiment, the material contacting surface is molded into a funnel-shaped portion of the hopper.

In another embodiment, the material distributed by the hopper is flour, and the step of placing the flour in the hopper and contacting the surface of the flour in contact with the material is also included.

In another embodiment, the material dispensed by the hopper is sugar, and the step of placing sugar in the hopper and contacting the surface of the sugar in contact with the material is also included.

In another embodiment, the device for manipulating the material is a funnel with an internal space for narrowing the flow of material along the way to the outlet, while the surface in contact with the material forms at least part of the surface forming the internal space.

In another embodiment, the device for manipulating the material is a trough with an inner space for directing the flow of material, while the surface in contact with the material forms at least a portion of the surface forming the inner space.

In another embodiment, the material handling device is a conduit with an interior space for guiding the flow of material, the surface in contact with the material forming at least a portion of the surface forming the interior space.

In another embodiment, the aluminum sheet has a static coefficient of friction that differs between any two given sheet orientations by no more than 5% relative to the direction in which the coefficient is measured.

In another embodiment, a device for handling a material with at least one surface in contact with the material includes: a surface formed from an aluminum sheet, at least partially forming a surface in contact with the material, wherein the aluminum sheet is rolled using a work roll, from 60% to 100% of the surface of which is covered with recesses that do not have faces and have a central region recessed relative to the average height of the surface and a protruding smooth periphery first projection having its apex in a greater height than the average height of the surface, the aluminum sheet has a static coefficient of friction in the range of 0.62 to 0.79.

In another embodiment, the recesses have a diameter in the range of 200 μm to 400 μm and a depth relative to the top of the peripheral protrusion in the range of 0.5 μm to 2.0 μm.

In another embodiment, the device for handling material is a hopper with an internal space for storing material, while the surface in contact with the material forms at least a portion of the surface forming the internal space.

In another embodiment, the material contacting surface is molded into a funnel-shaped portion of the hopper.

In another embodiment, the material handling device is a flour bin.

In another embodiment, the material handling device is a sugar hopper.

In another embodiment, the device for manipulating the material is a funnel with an internal space for narrowing the flow of material along the way to the outlet, while the surface in contact with the material forms at least part of the surface forming the inner surface.

In another embodiment, the material handling device is a gutter with a guide surface capable of guiding the material, while the surface in contact with the material forms at least a portion of the guide surface.

In another embodiment, the material handling device is a conduit with an inner guide surface capable of guiding the material, wherein the surface in contact with the material forms at least a portion of the surface forming the inner guide surface.

In another embodiment, the aluminum sheet has a static coefficient of friction that differs between any two given sheet orientations by no more than 5% relative to the direction in which the coefficient is measured.

The formula claims a method of manufacturing a container for crushed material having an internal space, comprising molding from an aluminum sheet of at least one surface in contact with the crushed material, forming an internal space, characterized in that the aluminum sheet is subjected to molding, the static coefficient of friction of which is in contact with the crushed material material is 0.62 - 0.79, obtained by rolling with a work roll, the surface of which is 50% - 100% covered with recesses without conductive faces, with a central area recessed relative to the average height of said surface, and a peripheral protrusion protruding smooth, having in its top a greater height than the average height of said surface.

Preferably, the diameter of said recesses is between 150 and 400 microns, and their depth relative to the apex of the peripheral protrusion is 6 ± 2.0 microns.

Preferably, the container is made in the form of a hopper with an inner space for storing the crushed material, while at least part of the surface forming the inner space is made in the form of a surface in contact with the crushed material.

Preferably, the surface in contact with the crushed material is formed funnel-shaped.

Preferably, the container is for flour.

6 Preferably, the container is for sugar.

Preferably, the container is made in the form of a funnel with an outlet, the inner space of which tapers towards the outlet, while at least part of the surface forming the inner space is made in the form of a surface in contact with the ground material.

Preferably, the container is made in the form of a gutter with an inner space for guiding the crushed material, while at least part of the surface forming the inner space is made in the form of a surface in contact with the crushed material.

Preferably, the container is in the form of a pipeline with an inner space for guiding the ground material, with at least a part of the surface forming the inner space being in the form of a surface in contact with the ground material.

An aluminum sheet is preferably used, the static coefficient of friction of which, measured in any two directions, differs by no more than 5%.

The formula claims a container for crushed material having an inner space with at least one surface in contact with the crushed material, forming an inner space molded from an aluminum sheet, characterized in that said surface is molded from an aluminum sheet, the static coefficient of friction of which is in contact with the crushed material is 0.62 - 0.79, obtained by rolling with a work roll, the surface of which is 50% - 100% covered with recesses that do not have and faces a central area recessed relative to the average height of said surface and projecting a smooth peripheral projection having in its top a greater height than the average height of said surface.

Preferably, the diameter of said recesses is 200 to 400 microns, and their depth relative to the top of the peripheral protrusion is 0.5 to 2.0 microns.

Preferably, the container is made in the form of a hopper with an inner space for storing material, while at least part of the surface forming the inner space is made in the form of a surface in contact with the ground material.

Preferably, the surface in contact with the ground material is funnel-shaped.

Preferably, the container is for flour.

Preferably, the container is for sugar.

Preferably, the container is made in the form of a funnel with an outlet, the inner space of which tapers towards the outlet, while at least a part of the surface forming the inner space is made in the form of a surface in contact with the ground material.

Preferably, the container is made in the form of a chute with an inner space for guiding the ground material, with at least a part of the surface forming the inner space being made in the form of a surface in contact with the ground material.

Preferably, the container is made in the form of a pipeline with an inner space for guiding the crushed material, while at least part of the surface forming the inner space is made in the form of a surface in contact with the crushed material.

Preferably, the surface in contact with the crushed material is molded from an aluminum sheet, said static coefficient of friction of which, measured in any two directions, differs by no more than 5%.

Brief Description of the Drawings

For a more complete understanding of the present invention, reference is made to the following detailed description of exemplary embodiments that are discussed in conjunction with the accompanying drawings.

Figa and 1b are graphical images, respectively, of a top view and a perspective view (3D) of surface morphology for a surface sample of a work roll made using EDT texturing, as measured by optical profilometry.

Figure 2 is a schematic illustration of a device for surface treatment of work rolls in accordance with an embodiment of the present invention.

Fig. 3a is a top view of a surface morphology for a surface sample of a work roll made according to a method in accordance with an embodiment of the present invention, as measured by optical profilometry. Fig. 3b is an enlarged image of a fragment of Fig. 3a, and Figs. 3c and 3d are graphical images of the perspectives of the surfaces shown in Figs. 3a and 3b, respectively, as measured by optical profilometry.

Figures 4a and 4b are graphical views, respectively, of a top view and a perspective (3D) surface morphology for a surface sample of a work roll made according to a method in accordance with an embodiment of the present invention, as measured by optical profilometry.

Fig. 5a is a graphical top view of the surface morphology of a sample of a rolled aluminum sheet in accordance with an embodiment of the present invention, while rolled using a work roll manufactured according to the method in accordance with an embodiment of the present invention, as measured by optical profilometry. Fig. 5b is an enlarged image of a fragment of Fig. 5a, and Figs. 5c and 5d are graphical images of perspectives of the surfaces shown in Figs. 5a and 5b, respectively, as measured by optical profilometry.

6a, 6b, and 6c are graphical top views of the surface morphology of three samples of a rolled aluminum sheet in accordance with an embodiment of the present invention, while rolled using a work roll made according to the method in accordance with an embodiment of the present invention, at 10% reduction, 20% reduction and 40% reduction, respectively, according to measurements using optical profilometry. Fig.6d, 6e and 6f are graphical images of the perspectives of the surfaces shown in figa, 6b and 6c, respectively, according to measurements using optical profilometry.

FIGS. 7a and 7b are photographs of work rolls whose surface has been machined in accordance with an embodiment of the present invention, and FIGS. 7c and 7d are enlarged photographs of fragments of FIGS. 7a and 7b, respectively.

Fig. 8 is a graph of the effect of surface texture on the coefficient of friction.

Fig.9 is a diagram of a method of developing a surface texture in accordance with an exemplary embodiment of the present invention.

Figure 10 is a schematic illustration of a device for surface treatment of a work roll in accordance with another embodiment of the present invention.

11 is a schematic illustration of a device for surface treatment of a work roll in accordance with another embodiment of the present invention.

12 and 13 are respectively perspective and cross-sectional views of sheet-shaped means for treating a work roll surface in accordance with another embodiment of the present invention.

14 is a schematic illustration of a device for creating a gasket for surface treatment of a work roll in accordance with another embodiment of the present invention.

FIG. 15 is a schematic diagram of an apparatus for surface treatment of a work roll in accordance with another embodiment of the present invention.

FIG. 16 is a schematic diagram of an apparatus for surface treatment of a work roll in accordance with another embodiment of the present invention.

17 is a perspective view of a surface texture of a sheet obtained using a roll that has been sanded in the usual manner.

Fig. 18 is a schematic illustration of a structure for storing material in accordance with another embodiment of the present invention.

FIG. 19 is a schematic diagram of a structure for manipulating material in accordance with another embodiment of the present invention.

FIG. 20 is a schematic illustration of a structure for manipulating material in accordance with another embodiment of the present invention.

21 is a schematic illustration of a device for testing the coefficient of friction.

Detailed Description of Exemplary Embodiments

An aspect of the present invention is to identify that, for many applications of sheet metal, a uniform, isotropic appearance of the treated surface, that is, a surface that looks isotropic and diffusely reflects light, is desirable. In addition, the present invention reveals that, in addition to influencing the appearance, oriented in a certain direction, the surface roughness of a sheet rolled using polished work rolls influences the molding processes that can be used to form products of a given shape, such as a panel, from sheet metal a car, for example, due to changes in the frictional interaction between the forming tool and the sheet material due to oriented in a certain direction enii texture / grinding traces on the surface of the metal sheet that have been transmitted work rolls. The present invention also reveals that a more isotropic surface is beneficial in carrying out certain molding processes that are applied to an aluminum sheet.

One of the ways to obtain a more isotropic surface on the work roll, which is used for rolling an aluminum sheet (primarily for a sheet), is to treat the surface of the roll using an electric discharge texturing (EDT) machine. An EDT texturing head with a row of electrodes can be placed near the roll surface to create an electric discharge / spark / arc from each electrode to the roll surface, causing local roll surface melting at each spark passage and causing the molten steel to form small pools of molten metal in the respective craters . The operation of the EDT machine along the surface of a rotating roll results in an improved isotropic surface, but one that is characterized by the presence of numerous microscopic craters in the range of up to 100 μm in diameter and with crater edge heights of up to 15 ~ 20 μm (Fig. 1).

Applicants have discovered that the edges of microscopic craters formed by the EDT method can be so brittle that when textured rolls according to the EDT method are used in a rolling mill, high contact pressure, for example, up to 1.38 GPa, between the work roll, sheet and / or with a back-up roll, can erase the isotropic texture and lead to the formation of wear particles that are deposited on the surface of the sheet, on the rolling mill and in the lubricant.

Figure 1 shows a sample of surface morphology for surface S1 of a work roll used according to the EDT method used for rolling an aluminum sheet. As can be understood, the surface morphology can be characterized as being coated with numerous sharp peaks and troughs of 5.0 μm in size relative to the reference plane.

Figure 2 shows the device 10 for processing the roll, having a chamber 12 for accommodating the work roll 14. The work roll 14 can be mounted in bearings 16, 18, to allow rotation, for example, due to the motor 20 connected to the work roll 14. The chamber 12 also houses a sand / shot blasting nozzle 22, which can be mounted on a frame 24, which allows the nozzle 22 to selectively move along the roll and be placed at a predetermined location, for example, due to the action of a motor 26 rotating a screw gear or driving chain, rack, wire-rope transmission, or driving by means of a friction gear driven by an engine connected to the nozzle 22. The nozzle 22 is powered by a compressor 28 and a hopper 30 for the means. In the nozzle 22, compressed gas, such as air, from the compressor 28 and the means 32 from the hopper 30 are mixed, while the means 32 is pushed and directed to the outer surface S of the roll 14. The means may be in the form of steel, glass or ceramic balls, grinding grain or other sandblasting / shot blasting agent as described further below. Computer 34 can be used for program control: the position of the nozzle 22, controlling the motor 26, the rotation of the roll, controlling the motor 20, the operation of the compressor 28 and the feed rate of the means 32 from the hopper 30. The video system 36 can be placed inside the camera 12 to monitor the state of the surface S to determine whether a predetermined target surface texture has been achieved during the operation of the roll processing apparatus 10. This video system may be attached to the nozzle 22 or independently movable on the frame 24, may include an enlarged image and a protective device to protect the inlet of the lens and lens from the entry of means 32. The means 32 discharged through the nozzle 22 can be transmitted through the funnel-shaped part 38 of chamber 12 to the recirculation line 40, which returns the means 32 to the hopper 30, for example, by feeding with a screw or under the action of compressed air, a blower fan or suction. The chamber 12 may be provided with a door (not shown) and a viewing window (not shown) to facilitate the movement of the roll 14 in and out of the chamber 12, as well as to monitor the operation of the device 10 for processing the roll. The nozzle 22 and compressor 28 may be of industrial type to achieve the desired intensities of the shot blast to create the desired surface topography.

In another embodiment, the nozzle 22 may be manual, as in a conventional shot blasting apparatus. The compressor 28 and the nozzle 22 can be adjusted to obtain an outlet pressure corresponding to a given shot blast intensity, that is, either manually or under computer control, to control the speed of the means 32 discharged from the nozzle 22 to allow the use of various types of means 32, and allow various operating parameters, such as roll hardness 14, initial surface texture and type of texture desired for surface S, for example, due to the depth and perimeter of the pits / craters created on p the surface of the roll with a predetermined means 32, such as steel balls / shot. The number of strokes and the dimensions of the recesses created by the tool on the surface area of the roll relative to the total area can be described as “% coverage” and can be adjusted by setting the compressor power, the expense of the tool and the speed of the nozzle 22 relative to the roll 14 as the nozzle 22 runs along the entire length of the roll 14 and / or as the roll 14 is rotated by the motor 20. The control of the shot blasting process can be automatic or manual. For example, a person can manually hold, place and move the nozzle 22 and / or the roller 14, as in conventional shot blasting processes in which the person is equipped with protective equipment and partially or completely enters the chamber containing the workpiece. A visual or microscopic inspection of the roll may be carried out to verify that the operating mode is suitable or to adjust the device 10, as well as to check the roll 14, the surface of which is suitably treated, at the end of the shot blasting / sandblasting process.

Alternatively, the nozzle 22 may be located inside a removable container with an open side (not shown) that is pressed against the surface S, forming a movable bead-blasting chamber, which captures and redirects the used means back to the storage tank, such as the hopper 30. This camera shot blasting can be placed at a predetermined location and moved manually or mechanically, including using a feed mechanism driven by an engine, such as frame 24, and optionally under control to computer 34.

The device and methods according to the present invention can be used to process the surface of a work roll that gives a given desired surface to the sheet when it is rolled to a predetermined size, for example, to give the sheet an isotropically diffuse or bright appearance, eliminating the need to emboss or use a training pass to create textured sheet. In this context, “bright” is called mirrored, and “diffuse” is called non-mirror appearance. Surface textures can be changed to achieve the desired desired appearance and technical capabilities during molding, associated with frictional properties, due to a suitable choice of tool and operating parameters.

In accordance with one aspect of the present invention, the desired texture is applied to the surface of the work roll, for example, S by a bead-blasting / sandblasting method, in which the selected medium is pushed towards the surface of the work roll S through the nozzle 22 due to air pressure. Adjust the pressure, the processing time per unit area, for example, in the form of a functional dependence of the speed of rotation of the work roll 14 and the speed of movement of the nozzle 22, the configuration of the nozzle 22 and the type of tool 32 to obtain the desired texture of the work roll, which is affected by size, shape, density, the hardness, speed of the agent 32 and the final depth, width and shape of the pits / craters or indentations, as well as% coverage with the pits / craters of the treated surface area S. In accordance with some embodiments of the present of the invention, the selectable tool 32 includes a recessed spherical tool that creates smooth craters, such as high-quality, precision steel bearing balls or shots, shot (glass, ceramic). Depending on the properties required for the final surface, mixtures of shot and grinding grain such as alumina, silicon carbide or other types of grinding grain can be used.

3a-3d are graphical representations of surface morphology as measured by optical profilometry for the surface of a work roll whose surface has been machined in accordance with an embodiment of the present invention. The surface S ₃ shown in figa-3d, was subjected to bead blasting using steel bearings balls grade 1000 with a diameter of ≤0.125 inches and a Rockwell hardness of ≥60. Grade 1000 has a tolerance of 0.001 inch for sphericity and ± 0.005 inch for diameter. The best grades of bearing balls can also be used. The distance of the nozzle 22 from the roll 14 may be from about 1 inch to about 12 inches, with a distance of about 5 inches being preferred for some applications. As you can understand, the use of bearing balls as a means for shot blasting leads to the formation of craters with a uniform shape on the surface of the work roll and the absence of sharp, raised edges, which are common for textures obtained according to the EDT method. Namely, the use of a spherical tool leaving a recess creates many smooth recesses located in the center of the crater that mimic the shape of the spheres / balls that create them, as well as smooth peripheral rises or protrusions around the recesses formed by displacing the material from the recesses. A gradual change in the slope is observed along the surface, and sharp edges or discontinuities are minimized. Typically, the depth of each recess in the center is below the average height of the surface, and the tip of the peripheral protrusion is above the average height. In order to create a smooth surface, the spherical product leaving the recesses should not crumble at the level of force required to create craters of the required depth. Otherwise, the spherical tool will break, and the resulting sharp edges and flat faces on the broken tool will lead to the formation of faces on the surface of the work roll. These recesses with faces may appear upon impact or later when the spherical tool is reused and hits the surface again. In addition to preventing the breaking of the spherical means, it is advisable that the force applied by the means, taking into account the size, speed and density of the spheres, does not create such a trajectory of motion upon impact, which leads to the formation of side grooves, having a significant component with the direction parallel to the surface of the means.

In general, smooth irregularities on the surface S _{3 of the} work roll, as a rule, have a value in the range of ± 3-6 microns, however, if necessary, craters of any desired size can be obtained, for example, more than 10 microns or less than 3 microns. As described in more detail below, a smooth wavy surface obtained using a spherical leaving groove, such as bearing balls, can be obtained, for example, by the random arrangement of craters, which can be expected from the sandblasting process, or by a discrete arrangement of craters, as explained below. A typical surface obtained according to the EDT method has a greater number of strong surface drops. Work rolls subjected to bead-blasting using bearing balls, as described above, can be used to produce a bright sheet with isotropy in appearance, depending on the initial surface of the roll before processing. Although grade 1000 ball balls have been described above, other types of precision balls, such as higher grade ball balls, can be used depending on the hardness of the roll. As noted, the spherical tool selected in order to create recesses on the surface of the roll is preferably selected with such material properties, namely density, hardness, elasticity, compressive strength and tensile strength, which allow the ball to hit and leave the recess on the roll set hardness in the absence of breaking or formation of faces as a result of impact.

Figures 4a and 4b show a work roll surface S ₄ obtained in accordance with another embodiment of the present invention. Namely, Fig. 4a is a top view according to measurements using optical profilometry of the topology of the surface of the work roll, which was sandblasted using a mixture of grinding grains of aluminum oxide (grinding grains 120: 180 in a 2: 3 ratio), and then shot blasting with using glass beads of AC grade (60-120 mesh). Sandblasting with alumina grinding grain was carried out in such a way as to remove traces of preliminary grinding on the roll (if detected by visual assessment), after which shot blasting was performed using glass beads to obtain the desired diffuse surface appearance. Fig. 4b is a graphical perspective view (3D) of surface morphology for surface S ₄ shown in Fig. 4a, as measured by optical profilometry. As can be understood from FIGS. 4a and 4b, the use of glass beads resulted in a surface S ₄ having fewer sharp protrusions than the surface obtained according to the EDT method, while the magnitude of the surface drops is lower than for the surface obtained according to the method EDT. Fig. 4b shows surface drops in an approximate range of ± 2.0 μm. Accordingly, it is possible to fairly characterize the final surface S ₄ as smoother than the surface obtained according to the EDT method, but still having micro roughness, which can be used to give the appearance of a diffuse isotropic surface to an aluminum sheet that is rolled using a work roll having this type of surface .

In accordance with the present invention, shot peening of the surface of the work roll results in a surface that is less brittle than the surface of the work roll, which was processed according to the EDT method. As a result, the surface of the work roll (texture) lasts longer, can withstand higher pressures applied to the surface and forms fewer wear particles when used for rolling. According to an embodiment of the present invention, when a spherical tool is used to treat the surface of the work roll, such as bearing balls or glass beads, the gently undulating surface texture obtained on the work roll provides rolling advantages to produce an isotropic surface. Compared to conventional sanded work rolls or work rolls whose surface has been machined according to the EDT method, smooth irregularities contribute to less friction between the sheet and the work rolls, resulting in higher compression ratios over the thickness of the sheet before there is a loss of lubrication or damage to the surface of the roll . The texture of the work roll, the surface of which was machined in accordance with the present invention, does not wear out to the same extent as that of a conventional polished work roll, or the roll whose surface is machined according to the EDT method. Experiments have shown that in a rolling mill with a driven work roll, the textures that imparted the roll according to the methods of the present invention last 5 to 6 times longer than conventionally sanded surfaces of the roll, and higher reduction rates are possible than those obtained using work rolls, the surface of which was machined according to the EDT method, before the excess of the power limit of the rolling mill occurs and the lubricant breaks down. The surface morphology of the roll formed in accordance with an embodiment of the present invention can withstand a reduction in thickness of more than 10% to obtain the desired textured sheet, for example, up to 60%. This differs from work rolls, the surface of which has been machined according to the EDT method, which are typically operated at a reduction ratio of from about 8% to 10%. Obtaining higher degrees of reduction can potentially eliminate the necessary (e) otherwise passage (s) through the rolling mill to achieve the desired thickness.

Fig. 5a shows a sample of the surface AS _{5 of a} rolled aluminum sheet in accordance with the present invention, while rolled using a work roll 14 with a roll surface, such as the surface of the roll S ₃ , as shown in figa-3d, obtained according to the method in in accordance with an embodiment of the present invention. Fig. 5b is an enlarged image of the surface shown in Fig. 5a, both images being obtained using optical profilometry. 5c and 5d are graphical perspective views (3D) of the sample depicted in FIGS. 5a and 5b, as measured by optical profilometry. A sheet obtained in the same manner as that shown in FIGS. 5a-5d was obtained by bead-blasting using precision steel bearing balls. As the macro-texture is illustrated as a whole, for example, pits / depressions obtained by shot-blasting, transferred to the metal sheet by work rolls during the rolling process, is an inverse of the texture on the work roll. However, both macro- and microelements affect the final level of surface brightness, that is, the final degree of specular reflection for the sheet.

6a, 6b, and 6c are graphical top views of surface morphology for three surface samples AS _6a , AS _6b, and AS _6c of a laminated aluminum sheet in accordance with an embodiment of the present invention, rolled using a work roll obtained according to the method in according to an embodiment of the present invention, at 10% reduction, 20% reduction and 40% reduction, respectively, as measured by optical profilometry. The surface of the work roll used to roll these samples was sandblasted using an alumina grinding grain, followed by shot blasting with a glass bead as described above with respect to FIGS. 4a and 4b. Fig.6d, 6e and 6f are graphical images of the perspectives of the surfaces shown in figa, 6b and 6c, respectively, according to measurements using optical profilometry.

7a and 7b are photographs of work rolls whose surface has been machined in accordance with an embodiment of the present invention. 7c and 7d are enlarged photographs of fragments of FIGS. 7a and 7b, respectively. The roll shown in FIGS. 7a and 7c was shot blasted using grade 1000 steel bearing balls with a diameter of 1.6 mm. The roll was shot blasted under conditions that contributed to 100% coverage of the surface of the S _7a roll with pits / recesses. The roll shown in FIGS. 7b and 7d was shot blasted using steel bearing balls of grade 1000 with a diameter of 2.36 mm. The roll was shot-blasted under conditions that contributed to 50% coverage of the surface of the S _7b roll with pits.

In accordance with an embodiment of the present invention, the sheet can be obtained using a standard rolling production mode, eliminating the need to emboss or use a training pass on the rolling mill. The final surface textures of the work roll do not wear out at the same speed as the surface obtained by processing according to the EDT method, and the usual polished surface of the roll. As a result, the service life of the roll is 5-6 times longer than the service life of conventional rolls. On a rolling mill with a driven work roll, production is not limited to “wide to narrow” production schemes, since the texture does not contribute to the formation of ring defects as a result of wear. As noted above, obtaining a sheet using a work roll, the surface of which was subjected to bead-blasting, for example, using bearing balls, leads to the formation of fewer wear particles than in the case of a surface treated according to the EDT method, or a normal ground surface, which leads to Greater purity of grease and sheet during the rolling process. The final leaf has isotropy in appearance.

On Fig shows the direction-dependent coefficient of friction during the molding of various surfaces during molding in the longitudinal (L) and transverse (T) directions. As for sample 6022-T43, the bead-blasted surface shows an average decrease in friction and a smaller change in friction depending on the direction of molding. Isotropy with respect to frictional interaction with forming tools, such as those used during drawing and drawing with thinning, can mean an improvement in the quality of the molding, for example, obtaining more uniform deformation during drawing and extended deformation limits when drawing.

In accordance with the present invention, the requirements for the initial appearance of the machined surface of the work roll before shot blasting, for example, using ball bearings, depend on the requirements for the final appearance of the sheet, for example, with a high degree of specularity or a small degree of specularity. The initial roughness should preferably be <1 microinch if an isotropic surface with a high degree of specularity is required. If a surface with a lower degree of specularity is required, the initial grinding traces on the work roll can be any desired grinding traces with a depth of up to 50 microinches. The required degree of preliminary grinding affects the final cost of the entire process, since obtaining the appearance of a treated surface with a roughness <1 microinch is usually more expensive. The requirements for the initial appearance of the machined surface of the work roll before shot blasting using glass beads or other means to obtain a diffuse surface preferably include a roughness of <15 microinches, or a roughness in which no grinding marks are observed on the roll after shot blasting of the work roll. Removing the initial traces of grinding on the roll during shot blasting using glass beads will depend on the parameters of the shot blasting selected to obtain a diffuse appearance of the treated surface. The present invention is further illustrated by the following examples.

Example 1

3a-d, 7a and 7c show images of exemplary work roll surfaces S ₃ , S _7a obtained in accordance with an exemplary embodiment of the present invention. To create the surface shown, the initial roll topography is created using the conventional grinding (pre-grinding) method to obtain a roughness of approximately <5 microinches. On the surface of the roll, a series of pits with a diameter in the range from 200 to 300 μm is obtained by shot peening using steel balls of grade 1000 with a diameter of 1.6 mm and a Rockwell hardness of ≥60. The balls are pushed to the surface of the roll having a Rockwell hardness of from about 58 to 62, with a speed causing pits with a diameter of from about 200 microns to 400 microns and a pit depth of from about 0.5 microns to about 4 microns. The processing conditions (ball speed) affect the diameter and depth of the pits, and they depend on the initial hardness of the work roll. In this example, approximately 100% of the surface area is pitted as estimated by visual inspection, but the coating may vary from about 10% to about 250%, depending on the desired appearance of the treated surface. Coating from 60% to 100% provides the surface of the work roll, which allows you to get an aluminum sheet with the required optical and mechanical properties. The measured% coverage may vary depending on the measurement method. Optical methods, as a rule, give an overestimated estimate of coverage compared with the physical method of measurement based on topographic images.

In accordance with another embodiment, the speed of the balls can be adjusted so as to obtain recesses having a diameter of from 150 μm to 400 μm and a depth relative to the top of the peripheral protrusion in the range of 6 ± 2 μm.

Significant advantages when using such rolls for rough rolling include: exclusion of passes (1 pass is excluded during cold rolling, 3 passes are excluded during hot rolling); the ability to roll from narrow to wide strips; extended roll life; the formation of a smaller layer of metal adhering to the roll during hot rolling due to reduced material transfer; and reduced formation of wear particles during cold rolling.

Example 2

According to another exemplary embodiment of the present invention, a work roll with a diffuse surface can be obtained by shot-blasting a work roll that has previously been ground to obtain a roughness of <5 microinches. The tool can be a glass bead, other types of "ceramic" bead grades from A to AH, which correspond to sizes from 20-30 mesh to 170-325 mesh, or other solid abrasive particles such as aluminum oxide (grinding grain sizes from 12 to 400). In order to obtain an identical appearance of the treated surface shown in FIGS. 4a and 4b, it may be necessary to consistently use a combination of glass beads, ceramic beads and alumina products. For example, the surface of the roll is first treated with alumina in the form of a mixture of grinding grains of various sizes (grinding grains 120 and 180 in a 2: 3 ratio) using a nozzle with a 5/16 inch working hole and a pressure of 65 ft per square meter. inch at a speed of movement along the roll of 1.5 inches per minute, then with a glass bead of grade AC (60-120 mesh) at 100 feet per square inch using a nozzle with a working hole of 3/8 inch and a speed of movement along the roll of 1.5 inches per minute. The distance was adjusted based on the nozzle jet lengths for a particular shot blasting system. The choice of nozzles, pressures and speeds along the roll will depend on the device used for the implementation of shot peening. The relative area of the coating may have a value in the range from 10% to 250%, depending on the desired appearance of the treated surface.

A work roll whose surface has been machined in accordance with the above parameters can be operated with a compression ratio in the range of 10 to 60% (unlike rolls machined according to the EDT method, which are typically operated with a compression ratio of approximately 8% to 10 %). A higher reduction ratio can be used to eliminate one or more crimp passages that might otherwise be required to obtain the desired thickness and surface appearance. The final leaf has isotropy in appearance and isotropy with respect to functional characteristics.

Figure 9 shows a diagram of a method of developing a surface texture in accordance with an exemplary embodiment of the present invention. At the first stage (I) (not shown), surface topologies are predicted, which are obtained using a number of shot blasting conditions and types of products. With respect to the surface of the work roll to be shot blasted, the size of the product, the composition and the conditions of the shot blasting process, such as the rate and% of coating, can be selected to adjust the desired final texture of the roll, which is then transferred to the rolling. The relationship between these parameters (size of the tool, composition and conditions of the shot peening process) and the obtained results of surface treatment can be recorded and used as the basis for predictive computer simulation in stage I for any given set of parameters to obtain a roll surface texture.

In the next stage (II) (shown in Fig. 9), light scattering and appearance are predicted for a given set of real or hypothetical surface topographies. As shown in FIG. 9, the simulation may include selecting a “target” surface that has certain optical properties, such as predicted light scattering, for example, to obtain a given degree of brightness. The method of creating an aluminum sheet having the desired optical properties can then be carried out by the following steps:

(A) an accumulation of a data array that compares a plurality of predetermined surface profiles with the corresponding optical properties of each surface profile, including light scattering, linear dimensions and surface treatment parameters used to obtain each of the plurality of surfaces; (B) implicit specifying of a hypothetical surface by specifying certain target optical properties; (C) modeling a hypothetical surface by searching and selecting data related to at least one surface profile with the measured or predicted optical properties closest to the target optical properties; (D) comparing the target optical properties with the optical properties of at least one surface profile; (E) when the comparison in stage (D) does not indicate identity, the next step is to search and select other data in the data array related to another surface profile that has measured or predicted optical properties that are close to target properties, but diverge from target properties in the opposite respect as to how the optical properties of at least one given surface profile differ from the target properties; (F) take the optical properties of at least one surface profile and another surface profile in proportion to their respective deviations from the target properties in order to arrive at the adjusted optical properties of the adjusted hypothetical surface, and record the contributions of at least one surface profile and another surface profile to the folded trial combination; (G) comparing the optical properties of the adjusted simulated surface with the target optical properties to ensure that differences between them are reduced; and then repeat steps (E) to (G) until a slight improvement or lack thereof is noticed, as a result of which the best simulated surface is determined with respect to the target.

It should be noted that steps (C) through (G) can be performed as described or can be replaced by a non-linear least squares optimization algorithm to automate the process. To implement the method combine the simulation stage (I) and (II). Namely, by: (1) refining the surface treatment parameters used to obtain each of the many surfaces by combining these parameters in proportion to the contribution of the optical properties of each of the surface profiles folded into the best hypothetical surface, thus determining the best surface treatment parameters; (2) conducting the surface treatment of the roll in accordance with the best surface treatment parameters; and (3) rolling the aluminum sheet using a roll, the surface of which was machined in step (I). As you can see after receiving a simulated solution, the corresponding parameters of shot peening can be realized when processing the surface of the work roll. The actual results of the implementation can be stored in a database along with the parameters of the method, which led to the expansion of modeling capabilities due to these results.

10 shows an alternative apparatus 110 for surface treatment of work rolls 114a, 114b in accordance with another embodiment of the present invention. In the process of implementing the surface treatment method, which will be described below, the work rolls 114a, 114b are mounted in parallel and are able to rotate relative to each other, while they are fixed with their ends in suitable bearings (not shown), such as 16, 18 in figure 2, and driven by a motor or motors (not shown), such as motor 20, shown in FIG. The nozzle 122 for supplying funds, as well as the nozzle 22 in figure 2, can be held on the frame to move or place the nozzle 122 along the rolls 114a, 114b near the place where they converge, which can be called the gap N. The nozzle 122 can feed the tool, for example, bearing balls 132, into the clearance region N so that when the rollers 114a, 114b rotate in the directions shown by arrows, the balls 132 will pass between the rollers. Unlike the nozzle 22, the nozzle 122 does not have to push the balls 132 under pressure to achieve high speed, but can simply feed the balls 132 in a controlled manner. If the space between the rollers 114a, 114b is smaller than the diameter of the balls 132, then a mechanical stress condition is reached when they pass into the gap N. Considering that the balls 132 have comparable or greater hardness than the surface of the rollers 114a, 114b, and are sufficiently elastic, while have sufficient compressive strength to pass through the gap N without breaking, they will cause craters to form on the surface of the rolls 114a, 114b as they pass through the gap N. Craters on the surface of the rolls 114a, 114b are formed from pressure and not from the impact force balls released to the surface at high speed. After passing through the gap N, the balls 132 can be collected in the gutter or hopper 138 for reuse. The rolls 114a, 114b can be customizable to be able to move them closer to each other or further apart, narrowing or widening the gap N, to adjust to the balls 132 of different sizes and / or adjust the depth of the craters that form on the rolls 114a, 114b .

Fig. 11 shows a device similar to that shown in Fig. 10, having a different type of ball feed mechanism, i.e. an elongated hopper / funnel 230, which is capable of holding and supplying a supply of balls 232 so that the area between the gap N and the hopper / funnel 230 it was always completely filled with balls 232. Namely, balls 232, when passing through the gap, function as a linear barrier, causing a cork to form from balls falling through the hopper funnel 230 and prevent more balls from falling out. The funnel / hopper 230 may fit snugly into the normally V-shaped region above the gap N, limited by the rollers 214a, 214b, so that the balls 232 cannot pass between the rollers 214a, 214b and the funnel / hopper 230. As the balls 232 pass through the gap N, an additional number of balls flows out of the hopper / funnel 230 to replace them. The used balls 232 are collected in the trough 238 and again fed through the lines 240a, 240c and the recirculation device 240b. A baffle 242 at each end of the rolls 214a, 214b (only one shown) can be used to prevent the balls 232 from flowing over the ends of the rolls 214a, 214b by holding the balls 232 in a V-shaped region.

12 and 13 show sheet-shaped means 344 for treating the surface of a work roll in accordance with another embodiment of the present invention. The sheet-shaped means 344 may have a connecting part 344a, for example made of elastomer, in which a surface treatment means, for example a spherical recess leaving means 332, such as bearing balls, is included. According to another embodiment, the connecting portion 344a may be made of a sheet of paper or polymer to which surface treatment means are glued. The sheet-shaped means 344 can be used by a surface treatment device 110, 210, such as those shown in FIGS. 10 and 11, namely by passing through the gap N the sheet-shaped means 344 instead of the free balls 132, 232. If the connecting part 344a is sufficient elastic and tightly holds the balls 332, it is possible to obtain a continuous contour based on the means in the form of a sheet 344, which allows it to pass between the rollers 214a, 214b, moving in a circle to obtain the desired degree of coverage with craters. As shown in FIG. 12, the beads 332 can be dispersed throughout the sheet-shaped medium 344 in any desired manner, for example, as a complete, evenly distributed coating of the entire tool in the form of a sheet 344, a more diffuse structure, or random distribution.

14 schematically shows the surface of a substrate 446, for example, glass, which is coated with a layer of photoresist or photopolymer 448. A radiation source 452, such as ultraviolet light, an electron beam, or a laser, emits radiation R1. In the case of light, an optional radiation distributor 450, such as a photomask or a set of lenses, distributes the radiation R1 to produce a distributed set of emissions R2, which falls on the photoresist layer 448, forming a wavy structure 448a from more or less light. After the manifestation of the photoresist, a surface can be created having the desired texture with a smooth contour. In another embodiment, the photoresist layer can be exposed / shaped using a laser scanning device or an electron beam scanning device to create the desired exposure structure and final surface profile after development.

As described in US Pat. No. 7,094,502, issued to Schaefer et al, all rights reserved by the applicant of the present invention and which is incorporated herein by reference in its entirety, gasket 453 can be obtained from the surface profile of the developed photoresist layer 448. As described further in 7094502, the gasket 453 can be hardened by various metallization and coating methods to enable it to be pressed into the surface of the metal roll to ensure that its surface texture is transferred onto overhnost roll and then subsequently the surface of the product. In accordance with one aspect of the present invention, a pad 453 with a smooth, undulating surface profile can be used to impart this texture to a work roll, such as roll 114a and / or 114b. For example, a spacer 453 with such properties can be used as sheet-shaped means 344 when passing a spacer 453 between the rollers 214a, 214b of the device 210 shown in FIG. 11. In order to process the surfaces of both rolls 214a, 214b at the same time, two adjacent spacers 453, or a spacer 453 with two textured surfaces, can be used. Alternatively, the textured pad 453 may be attached to the surface of the work roll, for example, 214a by adhering it to the roll using adhesives, soldering, or welding and then used to roll the aluminum sheet.

15 schematically shows an ultrasonic shot blasting device 510 for treating the surface of a work roll 514 in accordance with another embodiment of the present invention. Ultrasonic shot blasting devices are commercially available, for example from Sonats SA, Nantes, Carquefou, France. In accordance with the present invention, such bead-blasting devices can be used to treat the surface of work rolls intended for rolling aluminum sheet, that is, if the speed, density, size, elasticity and compressive strength of the balls are such that a suitable crater depth is achieved on the surface of the treated roll in the absence of crushing / destruction means for shot blasting.

On Fig shows a device 610 for surface treatment of the work roll 614 in accordance with another embodiment of the present invention. A knurl 664 having a textured surface 664a is attached to the knurling head 662. Knurl 664 can rotate on axis 664b and is pressed into the surface of work roll 614 under the influence of significant force F. Since the contact area between runner 664 and work roll 614 is very small, force F focuses on a small area, transmitting surface texture 664a to roll 614, as shown by region 614a. The frame 624 can be used to allow the knurling head 662 to move along the work roll 614 to convey the desired texture to the entire surface of the roll 614. The work roll 614 can be rotated by an electric motor, causing the knurl 664 to rotate while it is texturing the work roll 614. An aspect of the present invention consists in ensuring that the end surface 614a (or the end surfaces of the work roll processed by the device described with reference to FIGS. 10-15) will have a structure corresponding to the above-described effect hydrochloric texture, such as that obtained by shot peening using the bearing balls, such as described above with reference to Figures 3a-3d. Texturing the work roll 614 using the device 610 may require more than one longitudinal passage of the knurling head 662 depending on the density of the surface texture for surface 664a (number of irregularities per unit area) and the desired% coverage.

On Fig shows the surface of the aluminum sheet M with a surface roughness obtained using a roll, the surface of which was processed by grinding. It should be noted that the X axis is expressed in mm, and the Y and Z axes are in microns. The polished rolls convey to the sheet a texture consisting of many elongated, parallel grooves. The surface of the sheet M is rough in all directions, while the roughness changes depending on the direction, which leads to an increase in frictional anisotropy when the sheet interacts with another object or objects. Typically, the roughness Ra of the roll, which is transferred to a conventional rolling sheet, can have a value in the range of from about 0.5 to 1 μm. An aspect of the present invention is to identify that the roughness and anisotropy of a conventional sheet rolled using sanded work rolls affect the functional characteristics of the sheet when used in some applications. Also in that a sheet made in accordance with the present invention, for example, made using a roll that has been subjected to bead-blasting with ball bearings as described above, can be used to obtain great advantages over a conventional sheet in some applications. For example, when a sheet is used in a structure for storing and / or directing the flow of materials such as grain, sugar, flour or other finely ground material, the sheet obtained in accordance with the present invention can reduce frictional interaction with the material and reduce the change in friction in depending on the direction, which leads to improved flow and greater flexibility in the development of structures for handling material.

FIG. 18 shows a storage container 705, such as a tank or bin for containing grain, flour, cereals, powdered foods such as milk, chocolate, spices, eggs, sugar, coffee, tea, or other flowing, ground, solid material 707, such as sawdust. Material 707 fills the container 705 to level L1, and various levels of filling within the container 705, for example, L2, may be allowed as it is dispensed from or fills the container 705. The loading pipe 709 is shown located near the opening 711 in the upper part of the container for placing the material 707 in the container 705. The container 705 may have a funnel-shaped part 713, which converges to the outlet 715. In the area of the outlet 715, a device for controlling the movement of material, such as a gate valve, impeller, screw device, cottages or pneumatic or vacuum feeder. Depending on the material stored in the container 705, various types of funnels 717, sieves 719 and outlet pipes 721 may be used. The inner walls 723 of the container 705 may be made of sheet metal, for example steel or aluminum. An aspect of the present invention is to identify that aluminum sheet material manufactured according to the methods disclosed herein may be preferred when used for manufacturing the inner walls of storage containers 705. Namely, a low coefficient of friction corresponding to an aluminum sheet obtained using rolls processed according to the method described herein, for example, with reference to the above example 1, may be a favorable condition for filling and distributing material, for example, flour or sugar from a container 705. If we take flour as an example, when it is loaded into a container 705 (which in this case can be a flour bin), the low static coefficient of friction allows the flour to pour from the inside surfaces, for example, 723 and fall to the lowest point of the container, which is not occupied by the material 707. The low static coefficient of friction of the inner surface 723 contributes to the self-distribution of the material 707 in the container 705. The material 707 present in the container 705 tends to take the lowest position with the lowest energy due to gravity (weight W of the material 707), but the weight of the material 707 is also the reason that the material spreads / diverges to the sides, applying a force F _E to the inner surface 723 of the container 705. When ma Since the material 707 moves relative to the inner surface 723, a friction force F _F arises which resists the movement of the material 707. For example, if the material 707 is distributed from the container 705, which leads to its movement from level L2 to level L1, the surface of the material 707 in contact with the internal surface 723 will create a friction force _F F along the area of contact, interfering with the movement of the material 707 and its distribution from the vessel 705. The frictional force _F F is more significant in the funnel portion 713, as with a smaller stavlyayuschaya weight W is parallel to the inner surface 723 to resist the frictional force _F F. When using the aluminum sheet material according to the present invention to create the inner surface 723, the static coefficient of friction is reduced relative to the sheet material having a normal surface (as in FIG. 17), which facilitates filling and distribution of material from the container 705. The static coefficient of friction for the material depends from the roughness of the material, which for a normal sheet will usually be from 0.5 to 1.0 microns. Comparable sheet material obtained using rolls, the surface of which was machined in accordance with the present invention, for example, by making dents using bearing balls, etc., as described above, will have a reduced surface roughness and an improvement in terms of static coefficient of friction from 10 to 30%. This improvement leads to the possible orientation (inclination) of the guide surface / storage surface that is in the path of movement of the material, such as flour, approximately 40-70 degrees relative to the horizontal plane, for example, for the funnel-shaped part 713.

A decrease in the static coefficient of friction reduces the energy generated as a result of friction during the handling of bulk materials such as flour, which reduces the risk associated with the explosion of a dusty air mixture. In addition, a decrease in the coefficient of friction of the inner surface 723 of the container with material 707, being a favorable condition for filling and distribution, can reduce the need for equipment for moving the material (paddle mixers, fans, screw drives, etc.) and energy for their supply. In addition, the increased ability to provide sprinkling of material 707 may contribute to the cleanliness of the inner surface 723 and the distribution of the material in the order of receipt. In the case of flour and other food materials 707, transferring the material in the order of receipt prevents the material from being stored in the container for an undesirably long period causing spoilage. The flour will become rancid if it sticks to the inner surface 723 of the container 705 and an excess amount of time is stored there. The inner surface 723, which provides a sprinkling of the contained material, allows it to fall to the bottom for earlier distribution. In addition, such a sprinkling can also increase the time between the required procedures for cleaning the container, which in the case of a large storage container, such as a flour bin, entails significant expense and inconvenience.

In addition to the storage structures, the characteristic features of the low static coefficient of friction sheet material made in accordance with the present invention can also be preferably used to make structures for moving the material. FIG. 19 shows a trough 805 having a complex helical shape and made of sheet metal, for example, an aluminum alloy, which has been machined using the rolls described in the present invention. Since the surface of the gutter 805 has a lower static coefficient of friction, it will be easier to pass materials, such as grain, flour, sugar, other materials, etc., than a gutter of a similar shape made from a material having a higher static coefficient of friction. As a result, the groove 805 can be used with a smaller slope and can be made with smaller dimensions than a similar groove made of sheet material with a large static coefficient of friction. While the gutter 805 involves movement due to gravity, a low friction sheet material will also facilitate movement along it in addition to the movement caused by a moving device, such as a pushing device, impeller, or other automated device.

On Fig shows a pipe or conduit 905 having a complex helical shape and made of sheet metal, for example, from an aluminum alloy, which is processed using the rolls described in the present invention. Since conduit 905 has a low static coefficient of friction, it will be easier to pass materials through itself than a conduit of a similar shape made of a material having a higher static friction coefficient, thereby alleviating design constraints imposed by sheet material having a higher static coefficient friction. The material transfer structure may not have a complex shape and may be an inclined flat surface, a straight pipe, or other simple shape and still have the advantage of having a lower static coefficient of friction.

On Fig shows a test device 1003 for testing static coefficient of friction μ_s sample sheet 1023 relative to a given material 1007, such as flour. For ease of illustration, it is assumed that the sample material 1007 has a weight starting from a single point, creating a gravitational (weight force) force F_W. F_W can be decomposed into a force perpendicular to the surface of the sheet 1023 F_N, and a force parallel to sheet 1023 F_Pwhich counteracts the friction force F_F. Friction Force F_F connected with perpendicularly directed force F_N using a static coefficient of friction as expressed in equation F_F= μ_s F_N. When parallel directed force F_P exceed friction F_F, the material 1007 will roll off the inclined surface of the sheet 1023. As shown by the angles A and B, the sheet 1023 can be placed at a selected angle relative to the horizontal plane to set the angle at which the material 1007 will slide. As described in the following examples, the aluminum sheet , formed in accordance with the present invention, has a lower static coefficient of friction than conventional sheet material, and therefore the material 1007, which is placed on the surface of the sheet 1023 slides at smaller angles relative to izontalnoy plane (with a smaller slope) than the corresponding conventional sheet material.

Example 1

An aluminum alloy sheet of 60 cm by 30 cm made using a ground roll, having a roughness of 0.78 μm, having a normal anisotropy, and a static coefficient of friction equal to 0.88 with respect to flour when tested in the direction parallel to the direction of the texture and a static coefficient of friction equal to 0.92 when tested in the direction perpendicular to the direction of the texture, was placed on the surface in a horizontal position. A similarly sized aluminum alloy sheet made in accordance with the present invention (the surface of which was machined using a roll that was shot peened using bearing balls in accordance with the method described in Example 1 above) and having a static coefficient of friction of 0.72 with respect to flour when tested in the first direction and a static coefficient of friction equal to 0.73 when tested in the second direction perpendicular to the first direction, was placed near the first about the sheet. A cup of flour weighing 25 g was poured onto the surface of each sheet in approximately the same place. Then the sheets were tilted with increasing angles relative to the horizontal plane. It was observed that the flour located on the sheet in accordance with the present invention, rolled down the sheet at an angle of 46 °. Flour, located on a regular sheet, did not slide down the sheet until the elevation angle reached 61 °. An ordinary sheet was placed with the direction of the texture parallel to the movement of the flour.

Example 2

In the second example, both the regular sheet from the first example and the sheet made in accordance with the present invention were again used with the same amount and type of flour as before, but both sheets were reoriented 90 degrees from their original position (thus, that the direction of the texture of a regular sheet was oriented in the transverse direction when tilted). The experiment was repeated. The flour rolled off the sheet in accordance with the present invention when the sheet reached an angle of 47 °, while the flour on a conventional sheet rolled down at an angle of 67 °.

The above examples showed that the aluminum sheet material made in accordance with the present invention has a lower static coefficient of friction than conventional sheet material, and also that the coefficient is less dependent on the orientation of the sheet. In addition, the interaction of a sheet with a lower coefficient of friction with flour allows the flour to glide at a less significant angle than for a conventional sheet. This difference in ease of sliding can be advantageously used in structures used for guiding, moving and storing materials such as grain, flour, sugar, salt, powdered or granular chemical products such as sodium bicarbonate, sawdust or any other similar materials. Reduced frictional interaction can be used to increase the volumetric flow of materials through gutters, pipes, funnels, pipelines and other hollow structures, thereby accelerating the transfer of material, eliminating or reducing the energy requirements of machinery, such as fans and impellers, to move such materials forward , reducing the complexity of the device for manipulating the material, the costs of manufacturing and maintenance, as well as energy consumption. Increased material transfer rates reduce the time and cost of transferring material. For example, with regard to filling the hopper with grain, flour or sugar from a truck, a 10% increase in transmission speed will lead to a 10% reduction in the time required for a vehicle, a team of workers, storekeepers, etc., each of which means significant cost reduction. Increased transfer speed and reduced friction also allow more efficient filling of containers such as the hopper, since granular materials such as flour or grain can more easily slide along the inner surfaces of the hopper as additional material is placed in it. Such gliding helps to place the added material, allowing it to be distributed rather than concentrated in certain areas, for example, under a loading pipe, which would otherwise lead to areas with low packing density and high packing density of the material. Reduced frictional interaction between materials and materials moving and containing materials also leads to greater freedom in the development of such structures, for example, reducing the slopes necessary to maintain the flow of a given material through the structure to manipulate the material. The same can be said about the isotropic nature of the coefficient of friction of the sheet material obtained in accordance with the present invention, since the isotropy in terms of properties allows structures to be manipulated to be fabricated without questioning the orientation of the sheet material texture. In addition to providing reduced frictional interaction regardless of the direction of the texture, isotropy in terms of properties also makes it easier to predict the movement of the material. For example, the trajectory of a material’s movement can be set based on geometry, as well as static and dynamic forces, independent of the direction of texture of the sheet material used to make the structure.

It should be understood that the embodiments described herein are merely given as examples and that one skilled in the art can make many changes and modifications without departing from the spirit and scope of the claimed subject matter. For example, in some part of the above invention, it is indicated that the range of roughness values (roll grinding), which is typically applied to aluminum rolling embracing the use of hot and cold rolling, is from <1 micro inch to 50 micro inch and that the standard Rockwell hardness a work roll for working with Al ranges from 50 to 70. Despite this, the methods and apparatus of the present invention can be applied to any treated surface with a roughness above 50 microinches and any hardness of the roll to achieve similar results by selecting means for shot blasting and adjusting the parameters of shot blasting, such as pressure and processing time, to influence% coverage. All such changes and modifications should be included in the scope of the present invention.

Claims (21)

1. A method of manufacturing a container for crushed material having an inner space, comprising molding from an aluminum sheet of at least one surface in contact with the crushed material, forming an inner space, characterized in that the aluminum sheet is subjected to molding, the static coefficient of friction of which is in contact with the crushed material is 0.62-0.79 obtained by rolling with a work roll, the surface of which is 50-100% covered with recesses that do not have faces, cent a rounded region recessed relative to the average height of said surface and a protruding smooth peripheral protrusion having at its apex greater height than the average height of said surface. 2. The method according to p. 1, characterized in that the diameter of the said recesses is 150-400 microns, and their depth relative to the top of the peripheral protrusion is 6 ± 2.0 microns. 3. The method according to p. 2, characterized in that the container is made in the form of a hopper with an inner space for storing the crushed material, while at least a part of the surface forming the inner space is made in the form of a surface in contact with the crushed material. 4. The method according to p. 2, characterized in that the surface in contact with the crushed material is formed funnel-shaped. 5. The method according to p. 3, characterized in that the container is designed for flour. 6. The method according to p. 3, characterized in that the container is designed for sugar. 7. The method according to p. 2, characterized in that the container is made in the form of a funnel with an outlet, the inner space of which narrows toward the outlet, while at least part of the surface forming the inner space is made in the form of a surface in contact with the ground material. 8. The method according to p. 2, characterized in that the container is made in the form of a gutter with an inner space for guiding the crushed material, while at least part of the surface forming the inner space is made in the form of a surface in contact with the crushed material. 9. The method according to p. 2, characterized in that the container is made in the form of a pipeline with an inner space for guiding the crushed material, while at least part of the surface forming the inner space is made in the form of a surface in contact with the crushed material. 10. The method according to claim 2, in which an aluminum sheet is used, said static coefficient of friction of which, measured in any two directions, differs by no more than 5%. 11. A container for crushed material having an inner space with at least one surface in contact with the crushed material, forming an inner space molded from an aluminum sheet, characterized in that said surface is molded from an aluminum sheet, the static coefficient of friction of which in contact with the crushed material is 0.62-0.79 obtained by rolling with a work roll, the surface of which is 50-100% covered with recesses that do not have faces, from the central Noah area recessed relative to the average height of said surface and projecting a smooth peripheral projection having in its top a greater height than the average height of said surface. 12. The container according to claim 11, characterized in that the diameter of said recesses is 200-400 μm, and their depth relative to the top of the peripheral protrusion is 0.5-2.0 μm. 13. The container according to claim 12, characterized in that it is made in the form of a hopper with an internal space for storing material, while at least part of the surface forming the internal space is made in the form of a surface in contact with the ground material. 14. The container according to claim 12, characterized in that the surface in contact with the crushed material is molded funnel-shaped. 15. The container according to claim 13, characterized in that it is intended for flour. 16. The container according to claim 13, characterized in that it is intended for sugar. 17. The container according to claim 12, characterized in that it is made in the form of a funnel with an outlet, the inner space of which narrows toward the outlet, while at least a part of the surface forming the inner space is made in the form of a surface in contact with the ground material. 18. A container according to claim 12, characterized in that it is made in the form of a gutter with an inner space for guiding the ground material, while at least a part of the surface forming the inner space is made in the form of a surface in contact with the ground material. 19. The container under item 12, characterized in that it is made in the form of a pipeline with an inner space for guiding the crushed material, while at least part of the surface forming the inner space is made in the form of a surface in contact with the ground material. 20. The container according to claim 12, characterized in that the surface in contact with the crushed material is molded from an aluminum sheet, the said static coefficient of friction of which, measured in any two directions, differs by no more than 5%.

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