Long shaftless screw conveying device

Abstract

To provide a long shaftless screw conveying device exceeding a 20m.SOLUTION: The non-shaft screw conveyance device 1 includes a non-shaft screw blade 10 exceeding a 20m part and within a 50m part, a trough 20 housing the non-shaft screw blade therein, a liner 30 disposed between an outer diameter end part of the non-shaft screw blade and an internal wall surface of the trough, a trough cover 22 covering the trough, a charging opening part through which a conveyance object is charged at one end part of one or both of the trough cover and the trough, and a discharge opening part through which the conveyance object is discharged at the other end part. And pressing parts 61 and 62 arranged at a predetermined interval from the outer diameter end of the non-shaft screw blade.SELECTED DRAWING: Figure 1A

Description

[Technical Field]

[0001] The present invention relates to a long and large shaftless screw conveying device. [Background technology]

[0002] The present applicant has made many inventions relating to shaftless screw conveying devices, and has disclosed that the length of the shaftless screw in the longitudinal direction is up to 20 m (see Patent Documents 1 to 4). The processing and welding of shaftless screws requires skilled techniques, and there are issues with strength (flexure) during transportation, so shaftless screws longer than 20m have never been offered.

[0003] In recent years, there has been a demand for shaftless screw conveying devices that are over 20 meters long. In particular, there is a demand for shaftless screws that are less likely to clog conveyed materials even when they are long and straight, and that have minimal deflection of the blades. There is also a demand for these devices to require less maintenance not only when installed above ground but also when installed underground.

[0004] There is also a demand for underground transport of small biomass fuels when transporting them from storage to a combustion furnace. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2023-61502 [Patent Document 2] Japanese Patent Publication No. 2023-90283 [Patent Document 3] Japanese Patent Application Publication No. 2023-61519 [Patent Document 4] Japanese Patent Application Publication No. 2023-68719 Summary of the Invention [Problem to be solved by the invention]

[0006] A first object of the present disclosure is to provide a shaftless screw conveying device having a length exceeding 20 m. A second object is to provide a shaftless screw conveying device that reduces clogging of conveyed materials and reduces deflection of the shaftless screw blades. A third object is to provide a shaftless screw conveying device that can reduce the need for maintenance in both above-ground and underground installations. A fourth object is to provide a shaftless screw conveying device that can suitably convey small biomass fuels. [Means for solving the problem]

[0007] The shaftless screw conveying device (1) of the present disclosure is A shaftless screw blade (10) having a length of more than 20m and less than 50m; a trough (20) having a U-shaped cross section that accommodates the shaftless screw blade (10) therein; a liner (30) disposed between the outer diameter end of the shaftless screw blade (10) and the inner wall surface of the trough (20); a trough cover (22) that covers the trough (20); Either or both of the trough cover (22) or the trough (20) may have an input opening (22a) at one end through which the transported material is input, and a discharge opening (20a) at the other end through which the transported material is discharged.

[0008] The shaftless screw conveying device (1) may have a driving means (15) connected to the flange (11) of the shaftless screw blade (10).

[0009] The shaftless screw conveying device (1) is Retaining portions (61, 62) may be provided partially or entirely on the inner surface of the trough, arranged above the rotation axis center (a0) of the shaftless screw blade (10) and parallel to the rotation axis of the shaftless screw blade (10) and at a predetermined distance (d4) from the outer diameter ends (P1, P2) of the shaftless screw blade (10). The "predetermined distance d4" is, for example, 3 mm to 8 mm.

[0010] The shaftless screw conveying device (1) may have a total length in the longitudinal direction exceeding 20 m and not more than 30 m, not more than 40 m, or not more than 50 m. The shaftless screw blade (10) may have a longitudinal central axis length (L) of more than 20 m and not more than 30 m, not more than 40 m, or not more than 50 m. The shaftless screw blade (10) may be configured by welding two or more shaftless screw blades in the longitudinal direction.

[0011] Another disclosed shaftless screw conveying device (1) is: The system may include a first conveying section (100) having a length of more than 20 m and not more than 30 m, and a second conveying section (200) having a length of more than 10 m and not more than 30 m, which is arranged in a straight line with the first conveying section (100). The first conveying section (100) a first shaftless screw blade (110) having a length of more than 20 m and not more than 30 m; a first trough (120) having a U-shaped cross section and accommodating the first shaftless screw blade (110) therein; a first liner (130) disposed between an outer diameter end of the first shaftless screw blade (110) and an inner wall surface of the first trough (120); and a first trough cover (122) covering the first trough (120). a first driving means (150) connected to the flange (111) of the first shaftless screw blade (110); The second conveying section (200) a second shaftless screw blade (210) having a length of more than 10 m and not more than 30 m; a second trough (220) having a U-shaped cross section and accommodating the second shaftless screw blade (210) therein; a second liner (230) disposed between an outer diameter end of the second shaftless screw blade (210) and an inner wall surface of the second trough (220); and a second trough cover (222) covering the second trough (220). The second drive means (250) may be connected to the flange (211) of the second shaftless screw flight (210). The first trough cover (122) may have a feed opening (122a) through which the material is fed, downstream of the first flange (111) in the conveying direction. The second trough (220) may have a discharge opening (220a) through which the transported object is discharged, located upstream of the second flange (211) in the transport direction.

[0012] Retaining portions (161, 162, 261, 262) may be provided partially or entirely on the inner surface of the trough, arranged above the rotation axis centers (a0) of the first and second shaftless screw blades (110, 210) and parallel to the rotation axis of the shaftless screw blades, at a predetermined distance (d4) from the outer diameter ends (P1, P2) of the shaftless screw blades. The "predetermined distance d4" is, for example, 3 mm to 8 mm.

[0013] The screw blade components of the shaftless screw conveying device (1) are determined by the thickness (t), width (w) and longitudinal length (e.g., 6 m) of the steel material. The screw blade components are arranged in series and adjacent tips are welded and fixed to form a continuous, long screw blade. For example, if a screw blade with an outer diameter of 200 mm and a pitch of 200 mm is machined from steel material that is 20 mm thick, 60 mm wide, and 6000 mm long, the longitudinal length (L) will be 1500 mm. To manufacture a 30 m long screw blade, 20 screw blades, each 1500 mm long, must be welded and fixed in a series. The length (L) of the shaftless screw blade in the longitudinal direction is, for example, more than 20 m and not more than 50 m. The outer diameter (r1) of the shaftless screw blade is, for example, 180 mm to 600 mm. The pitch (p) of the shaftless screw blade is, for example, 75 mm to 600 mm. The inner diameter (r2) of the shaftless screw blade is, for example, 30 mm to 300 mm. The thickness (t) of the shaftless screw blade is, for example, 15 mm to 23 mm. The blade width (w) of the shaftless screw blade is, for example, 60 mm to 80 mm.

[0014] The sum of the inner diameter (r2) and the blade width (w) is the outer diameter (r1). Alternatively, (r2 + w ≈ r1), where r1 is smaller if w is inclined and not extending perpendicularly from the radial direction. In another embodiment, the outer diameter (r1) is the sum of the inner diameter (r2) and twice the blade width (w). Alternatively, (r2 + w × 2 ≈ r1), where r1 is smaller if w is inclined and not extending perpendicularly from the radial direction. Two blades may be configured as one blade, with the outer surface of the second blade having a smaller outer diameter fixed to the inner surface of the first blade having a larger outer diameter (see FIG. 3).

[0015] The outer diameter (r1) of the shaftless screw blade is preferably 0.003 to 0.015 times the total length (L) of the shaftless screw blade. The relationship between the outer diameter (r1) of the shaftless screw blade and the pitch (p) of the shaftless screw blade is such that the pitch (p) is 0.5 to 1.5 times the outer diameter (r1), and preferably 1.0 times.

[0016] The shaftless screw blades (10, 110, 210) may have a rectangular cross section, for example. The larger the outer diameter (r1) of the screw blade, the larger the blade width (w) and blade thickness (t) are set. The total length (L), screw blade outer diameter (r1), pitch (p), blade inner diameter (r2), and blade width (w) are set according to the physical properties of the conveyed material and / or the conveyance amount per unit time (screw rotation speed) and the degree of mixing.

[0017] Examples of steel materials that can be used as raw materials for the shaftless screw blades and / or the trough and trough cover include general structural rolled steel materials (SS330, SS400, SS490, SS540, etc.), cold-rolled steel plates (SPCC, SPCD, SPCE, SPCF, SPCG, etc.), carbon steel materials (S25C, S30C, S35C, S45C, S50C, S55C, etc.), hot- or cold-rolled stainless steel plates (SUS304, SUS316, SUS430, SUS410, etc.), wear-resistant steel plates (HARDOX (registered trademark) from Swedish Steel Corporation, EVERHARD (registered trademark) from JFE Steel Corporation, etc.), high-tensile steel plates (SM570, SMA570W, etc.), and TMCP-type high-tensile steel plates (SM570TMC, SMA570WTMC, etc.).

[0018] Examples of steel materials that can be used as raw materials for the liner include general structural rolled steel materials (SS330, SS400, SS490, SS540, etc.), cold-rolled steel plates (SPCC, SPCD, SPCE, SPCF, SPCG, etc.), carbon steel materials (S25C, S30C, S35C, S45C, S50C, S55C, etc.), hot- or cold-rolled stainless steel plates (SUS304, SUS316, SUS430, SUS410, etc.), wear-resistant steel plates (HARDOX (registered trademark) from Swedish Steel Corporation, EVERHARD (registered trademark) from JFE Steel Corporation, etc.), high-tensile steel plates (SM570, SMA570W, etc.), and TMCP-type high-tensile steel plates (SM570TMC, SMA570WTMC, etc.). The liner may be constructed of a high hardness, wear resistant plastic material, an ultra-high molecular weight plastic, or the like.

[0019] The steel material used to make the shaftless screw blades and / or trough and trough cover is preferably a steel material with higher strength (higher tensile strength) than general structural rolled steel (SS400). This is preferable from the standpoint of wear resistance and durability. In the case of SS400, the total length of the screw blade shrinks by about 10% to 15% compared to its initial length after long-term use (for example, 6 months, 7 hours / day). However, stainless steel plates with higher strength (higher tensile strength) than SS400, such as wear-resistant steel plates (HARDOX (registered trademark) from Swedish Steel Corporation and EVERHARD (registered trademark) from JFE Steel Corporation), shrink to an extremely small extent.

[0020] Each of the first and second troughs may be a single member, or may be configured by connecting a plurality of members. The first and second troughs may be configured by a single member. The first and second liners may each be a single member, or may be configured by connecting multiple members. The first and second liners may each be configured by a single member. The first and second trough covers may each be a single member, or may be configured by connecting multiple members.The first and second trough covers may each be configured by a single member.

[0021] The "material to be transported" is not particularly limited, but examples thereof include various powders, granules, waste materials, wood chips, rice husks, coconut shells, and other biomass fuels. The particle size of the powder, grains, or shells may be, for example, 5 mm to 20 mm or less in maximum diameter.

[0022] [Effects of the invention] (1) We were able to provide a shaftless screw conveying device that was over 20m long. (2) There is less clogging of the transported material and the deflection of the shaftless screw blades can be reduced. (3) Maintenance opportunities can be reduced in both above-ground and underground installations. (4) Small biomass fuels can be transported suitably. [Brief explanation of the drawings]

[0023] [Figure 1A] FIG. 1 is an external view of a shaftless screw conveying device. [Figure 1B] FIG. 10 is an external view of another shaftless screw conveying device. [Figure 2] FIG. 10 is a schematic diagram showing an example of a distance d5 between blades at a connecting portion. [Figure 3] FIG. 2 is a diagram illustrating the outer diameter, inner diameter, and blade width of a shaftless screw blade. [Figure 4] FIG. 2 is a diagram illustrating a trough, a liner, a retainer, a shaftless screw blade, etc. DETAILED DESCRIPTION OF THE INVENTION

[0024] (Embodiment 1) The shaftless screw conveying device 1 of this embodiment will be described with reference to FIGS. Two shaftless screw blades are arranged in a straight line with a distance d5 between them to form a shaftless screw conveying device with a total length of 50 m. The shaftless screw conveying device 1 comprises a first conveying section 100 having a length of more than 20 m and not more than 30 m, and a second conveying section 200 having a length of more than 20 m and not more than 30 m, which is arranged in a straight line with the first conveying section 100.

[0025] The first conveying section 100 has a 30 m first shaftless screw blade 110, a first trough 120 with a U-shaped cross section that houses the first shaftless screw blade 110 inside, a first liner 130 arranged between the outer diameter end of the first shaftless screw blade 110 and the inner wall surface of the first trough 120, a first trough cover 122 that covers the first trough 120, and a drive means 150 connected to the flange 111 of the first shaftless screw blade 110. In FIG. 1, the first shaftless screw blade 110 has a pitch of 200 mm and an outer diameter of 200 mm.

[0026] The second conveying section 200 includes a 20 m second shaftless screw blade 210, a second trough 220 with a U-shaped cross section that houses the second shaftless screw blade 210 therein, a second liner 230 arranged between the outer diameter end of the second shaftless screw blade 210 and the inner wall surface of the second trough 220, a second trough cover 222 that covers the second trough 220, and a drive means 250 connected to the flange 211 of the second shaftless screw blade 210. In FIG. 1, the second shaftless screw blade 210 has a pitch of 200 mm and an outer diameter of 200 mm.

[0027] The driving means 150, 250 may be composed of a motor, a speed change gear, a connecting means, a control device, a power source, and the like. The driving means 150, 250 preferably rotates the shaftless screw blades 110, 210 at a rotation speed of 5 to 20 rpm, more preferably 8 to 15 rpm. Within the above rotation speed range, it is preferable to decrease the rotation speed as the outer diameter r1 of the shaftless screw blade increases, and increase the rotation speed as the outer diameter decreases.

[0028] The flanges 111, 211 of the first and second shaftless screw blades 110, 210 are provided at the base of the blade, which is different from the tip side of the blade.

[0029] The first and second trough covers 122, 222 are provided with, for example, an observation window for internal monitoring and an opening / closing section for maintenance.

[0030] 4 are disposed above the rotation axis centers a0 of the first and second shaftless screw blades 110, 210, parallel to the rotation axis of the first and second shaftless screw blades 110, at a predetermined distance d4 from the outer diameter ends P1, P2 of the first and second shaftless screw blades 110, 210, and are entirely provided on the inner surface of the first and second troughs. The "predetermined distance d4" is, for example, 3 mm to 8 mm, and preferably 3 mm to 5 mm.

[0031] 2 shows an example of the connecting section 300. At the connecting section 300 between the first conveying section 100 and the second conveying section 200, the distance d5 between the tip of the first shaftless screw blade 110 and the tip of the second shaftless screw blade 210 is, for example, 30 mm to 50 mm. Because steel expands and contracts depending on temperature, the screw blades are set in consideration of the degree of expansion and contraction and the degree of retention of the conveyed material. The first trough 120 and the second trough 220 may be connected (or abutting), the first liner 130 and the second liner 230 may be connected (or abutting), and the first trough cover 122 and the second liner 230 may be connected (or abutting).

[0032] The first conveying section 100 has an input opening 122a through which the transported object is input at an end different from the connecting section 300, and a discharge opening 220a through which the transported object is discharged at an end different from the connecting section 300 of the second conveying section 200. The input opening 122a is provided in the first trough cover 122. The discharge opening 220a is provided in the bottom of the second trough 220.

[0033] In this embodiment, the distances between the first and second shaftless screw flights 110, 210, the first and second liners 130, 230, the first and second troughs 120, 220, and the first and second trough covers 122, 222 are as follows: See FIG. 3 . (1) The distance d0 from the lowest end of the outer diameter of the shaftless screw blade on a vertical line z passing through the center of the rotation axis a0 of the shaftless screw blade to the lowest point z0 of the inner surface of the liner on the vertical line z is 0 mm (contact state). (2) The distances d1 and d2 from the left end and / or left end of the outer diameter of the shaftless screw blade on a horizontal line x passing through the center a0 of the rotation axis of the shaftless screw blade to the inner surface (left inner surface, right inner surface) of the liner on the horizontal line x are in the range of 10 mm to 25 mm. (3) The distance d3 from the uppermost end of the outer diameter of the shaftless screw blade on a vertical line z passing through the center a0 of the rotation axis of the shaftless screw blade to the inner surface of the trough cover on the vertical line z is in the range of 30 mm to 100 mm.

[0034] The troughs 20, 120, 220, liners 30, 130, 230, retainers 61, 62, 161, 162, 261, 262, and shaftless screw blades 10, 110, 210 will be described with reference to FIG. Retaining portions 61, 62, 161, 162, 261, 262 are arranged above the center a0 of the rotation axis of the shaftless screw blade 10, parallel to the rotation axis of the shaftless screw blade 10, and are arranged at a predetermined distance d4 from the outer diameter ends P1, P2 of the shaftless screw blade 10, and are provided partially or entirely on the inner surface of the trough. In this embodiment, the retaining portions 61, 62, 161, 162, 261, 262 are in contact with portions P1 and P2 at 30 degrees to the left and right of the boundary point P0 at the top of the outer diameter end of the shaftless screw blade 10. The predetermined distance d4 is, for example, 3 mm to 5 mm. This prevents the shaftless screw blade from floating significantly.

[0035] (Embodiment 2) The shaftless screw conveying device 1 of this embodiment is composed of a shaftless screw blade 10 having a total length of 50 m. The shaftless screw conveying device 1 shown in Figure 1B has a 50m shaftless screw blade 10, a trough 20 with a U-shaped cross section that houses the shaftless screw blade 10 inside, a liner 30 arranged between the outer diameter end of the shaftless screw blade 10 and the inner wall surface of the trough 20, a trough cover 22 that covers the trough 20, an input opening 22a at one end of the trough cover 22 through which the transported material is input, and a discharge opening 20a at the other end through which the transported material is discharged.

[0036] The shaftless screw conveying device 1 includes a driving means 15 connected to the flange 11 of the shaftless screw blade 10 .

[0037] The trough cover 22 is provided with, for example, an observation window for monitoring the inside and an opening / closing section for maintenance. The shaftless screw conveying device 1 may be buried underground, with the top surface of the trough cover 22 at the same height as the ground surface.

[0038] [Example 1] The longitudinal length L of the first shaftless screw blade was 30,000 mm, the longitudinal length L of the second shaftless screw blade was 195,000 mm, and a shaftless screw conveying device with a total length of 50 m was used. The distance d5 between the tips of the two screw blades was set to 40 mm. The blade thickness (t) was 20 mm on the inner diameter side and 25 mm on the outer diameter side, giving it a double blade structure. A 30,000 mm shaftless screw blade was manufactured by welding 20 shaftless screw blade components (L = 1,500 mm) in series. A 19,500 mm shaftless screw blade was manufactured by welding 13 shaftless screw blade components (L = 1,500 mm) in series. This shaftless screw conveying device was buried in the ground so that the top surface of the trough cover was at the same height as the ground surface.

[0039] Wood chips, rice husks, coconut husks, and their mixtures were used as biomass fuels. The outer diameter, inner diameter, and pitch of the shaftless screw blade were set as shown in Table 1. The shaftless screw blade was operated at a rotation speed of 13 rpm for 24 hours continuously, and the conveying conditions were good.

[0040] [Table 1]

[0041] [Example 2] A shaftless screw conveying device was used in which the length L of the shaftless screw blade was 49,500 mm. The outer diameter, inner diameter, blade width, blade thickness, and pitch were the same as in Example 1. This shaftless screw conveying device was buried in the ground so that the top surface of the trough cover was at the same height as the ground surface. The shaftless screw blade was operated at a rotation speed of 13 rpm for 24 hours continuously, and the conveying conditions were good. A 49,500 mm shaftless screw blade was manufactured by welding 33 shaftless screw blade components (L = 1,500 mm) in series. [Explanation of symbols]

[0042] 1. Shaftless screw conveyor 10. Shaftless screw blade 20 Trough 22 Trough cover 30 Liner 61, 62 Retainer

Claims

1. A shaftless screw blade exceeding 20m in length; a trough for accommodating the shaftless screw blade therein; a liner disposed between an outer diameter end of the shaftless screw blade and an inner wall surface of the trough; a trough cover that covers the trough; an input opening at one end of either the trough cover or the trough or both of the troughs, through which the transported object is input, and a discharge opening at the other end of the trough cover or the trough, through which the transported object is discharged; a retaining portion disposed above the center of the rotation axis of the shaftless screw blade, parallel to the rotation axis of the shaftless screw blade, and disposed at a predetermined distance from the outer diameter end of the shaftless screw blade; Shaftless screw conveying device.

2. A shaftless screw conveying device comprising a first conveying section having a length of more than 20 m and not more than 30 m, and a second conveying section having a length of more than 20 m and not more than 30 m, which is arranged in a straight line with the first conveying section, The first transport unit is a first shaftless screw flight having a length of more than 20 m and not more than 30 m; a first trough for accommodating the first shaftless screw flight therein; a first liner disposed between an outer diameter end of the first shaftless screw flight and an inner wall surface of the first trough; and a first trough cover for covering the first trough, The second conveying unit is a second shaftless screw blade having a length of more than 20 m and not more than 30 m; a second trough for accommodating the second shaftless screw blade therein; a second liner disposed between an outer diameter end of the second shaftless screw blade and an inner wall surface of the second trough; and a second trough cover for covering the second trough. a retaining portion disposed above the rotation axis centers of the first and second shaftless screw blades, parallel to the rotation axis of the shaftless screw blades, and at a predetermined distance from the outer diameter end of the shaftless screw blades; Shaftless screw conveying device.

3. At the connecting portion between the first conveying section and the second conveying section, the distance between the tip of the first shaftless screw blade and the tip of the second shaftless screw blade is 30 mm to 50 mm. The shaftless screw conveying device according to claim 2.

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