JP2011225299A - Conveyor trough structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conveyor trough structure that has superior slidability with a conveyor belt, by applying rust-proof paint to a steel plate trough in an air floating type rollerless conveyor.SOLUTION: The conveyor trough structure for supporting the conveyor belt in an air floating manner is adapted to apply alkyd resin to the surface of the trough to form a protective layer 20. Alkyd resin is dissolved in a solvent to produce alkyd resin paint which is applied to the trough and dried to form the protective layer. A substrate layer is formed on the trough, and alkyd resin is applied onto the substrate layer to form the protective layer.

Description

  The present invention relates to an air levitation rollerless conveyor for conveying coal or the like, and more particularly to a conveyor trough structure for levitating and supporting a conveyor belt when the conveyor belt is moved by air levitation.

  As shown in Patent Documents 1 and 2, an air floating rollerless conveyor is used as a conveyor for transporting coal.

  This air levitation rollerless conveyor supports the carrier belt and the return conveyor belt with a roller instead of a roller and supports the friction resistance when moving the conveyor belt on the trough. In order to reduce this, a wind box is provided at the lower part of the trough, air is supplied from the wind box between the trough and the conveyor belt, and the conveyor belt is lifted and moved on the trough.

  The trough structure in the air floating rollerless conveyor is formed by applying a rust preventive paint to a steel plate trough. Various anti-corrosion paints are commercially available, but they must be sufficiently slidable when in contact with the rubber of the conveyor belt.

  Commercially available rust preventive paints include modified epoxy resin paints, organic zinc rich primers, and lead zinc paints.

  Conventionally, among these rust preventive paints, a lead-tan zinc paint is used, so that the conveyor belt has better sliding properties than other rust preventive paints and is generally used.

Japanese Patent No. 3476005 JP 2003-31823 A

  However, since lead tan zinc contains lead in the paint, it tends to be abolished in terms of environmental burden.

  This inventor examined various physical properties of the rust preventive coating material which replaces a red lead zinc, As a result, came to make this invention.

  Then, the objective of this invention is providing the conveyor trough structure which solved the said subject and was excellent in the slidability with a conveyor belt.

  In order to achieve the above object, the invention according to claim 1 is a conveyor trough structure in which a conveyor belt is supported by floating air, and a protective layer is formed by applying an alkyd resin to the surface of the trough. Structure.

  The invention according to claim 2 is the conveyor trough structure according to claim 1, wherein the alkyd resin is dissolved in a solvent to form an alkyd resin paint, which is applied to the trough and then dried to form a protective layer.

  The invention according to claim 3 is the conveyor trough structure according to claim 1 or 2, wherein an undercoat layer is formed on the trough, and an alkyd resin is applied on the undercoat layer to form a protective layer.

  According to a fourth aspect of the present invention, in the protective layer, the friction coefficient with the rubber is 0.24 to 0.40, and the surface roughness Ra is in the range of 2 to 4 μm. Conveyor trough structure.

  According to the present invention, an excellent effect that the sliding property with the conveyor belt is improved by adopting a structure in which an alkyd resin is applied to the trough is exhibited.

1 is an overall perspective view of an air floating rollerless conveyor to which a conveyor trough structure of the present invention is applied. It is sectional drawing which shows the conveyor trough structure of this invention. It is a detailed sectional view of the conveyor belt in FIG. It is a figure explaining a friction tester. (A) The alkyd resin in this invention, (b) is a red lead zinc, (c) is a modified epoxy resin, (d) is a figure which shows each friction test result of an organic zinc rich primer. (A) is an alkyd resin in the present invention, (b) is a red lead zinc, (c) is a modified epoxy resin, and (d) is a diagram showing the test results of the surface roughness of each organic zinc rich primer.

  A preferred embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

  First, an air floating rollerless conveyor to which the conveyor trough structure of the present invention is applied will be described with reference to FIG.

  In the air floating rollerless conveyor 10, an endless conveyor belt 11 for conveying a transported object S such as coal is wound around a driving roller and a driven roller (not shown), and a carrier side belt 11a of the conveyor belt 11 is conveyed. A trough 12 (12a, 12b) having an arcuate cross section for supporting the belts 11a, 11b is provided below the return side belt 11b, and a wind box 13 (13a, 13b) is provided below the troughs 12a, 12b. In addition, air holes 14 (14a, 14b) for blowing the air supplied to the air boxes 13a, 13b to the carrier side belt 11a and the return side belt 11b are formed in the troughs 12a, 12b at appropriate intervals.

  Both sides of the troughs 12a and 12b are supported by the support legs 15, and the top covers 16 (16a and 16b) covering the carrier side belt 11a and the return side belt 11b are provided above the troughs 12a and 12b. Inspection windows 17 (17a, 17b) are provided on the top covers 16a, 16b.

  FIG. 2 shows the conveyor trough structure in the air floating rollerless conveyor 10 of the present invention. In the figure, the conveyor belt 11 and the trough 12 on the carrier side are shown, but the return side is the same.

  The trough 12 is formed of a steel plate in an arc shape in cross section, a wind box 13 provided below the trough 12 is connected to an air source 18, and the air flows from the air hole 14 to the trough 12 and the conveyor belt 11 as indicated by the arrows in the figure. The conveyor belt 11 (only the conveyor belt 11 on the return side) is floated by the air pressure and the carrier S on which the conveyed product S is placed.

  When constructing the air floating rollerless conveyor 10, the material is transported to the site and assembled. The trough 12 is formed by sequentially connecting steel plates having a predetermined length, but since the trough 12 is left on the site before assembling, a rust preventive paint is applied to the trough 12 as a protective layer 20. This rust preventive paint must have good sliding properties with the conveyor belt 11 in addition to rust prevention.

  FIG. 3 shows an enlarged cross-sectional view of the conveyor belt 11, which is formed by bonding a cover rubber layer 23 on the front and back of a cushion rubber layer 22 in which a wire 21 is embedded in the center. The rubber material of the cover rubber layer 23 is obtained by mixing and vulcanizing natural rubber, synthetic rubber, carbon, softener, and filler.

  In the present invention, the protective layer 20 is formed by applying an alkyd resin to the trough 12 as a paint in place of the lead red zinc paint. By forming the protective layer 20 with this alkyd resin, the trough 12 is not only rust-proof, but also the sliding property of the conveyor belt 11 is improved.

  As the alkyd resin, “Fast Drying Roswan” and “Fast Drying Roswan ZR-HB” manufactured by China Paint Co., Ltd. are suitable, but other alkyd resins can also be used.

  Alkyd resins are synthetic resins obtained by condensation reaction of polyhydric alcohols and polybasic acids. Fatty acid-modified phthalic acid alkyds, maleic acid alkyds, etc. are used, which can be obtained using ketones or ester solvents. It is said to be paint.

  In the present invention, the protective layer 20 is formed by applying an alkyd resin paint having a film thickness of 30 to 50 μm to the surface of the trough 12 by spray coating or the like and drying it. Further, before applying the alkyd resin paint, a primer layer such as an organic zinc rich primer may be applied to form a base layer, and the alkyd resin paint may be applied to the base layer to form the protective layer 20. .

  As described above, in the present invention, by using an alkyd resin as the protective layer 20 of the trough 12, the trough 12 can be rust-proofed and the protective layer 20 has excellent sliding properties with the conveyor belt 11. it can.

  Below, the friction test result at the time of using this alkyd resin and the case of using another rust preventive paint (lead tan zinc, a modified epoxy resin, an organic zinc rich primer) is demonstrated.

4 (a) and 4 (b) show an outline of a block-on-disk friction tester, FIG. 4 (a) is a schematic view (plan view) of the tester from above, and FIG. ) Is a schematic view (side view) of the testing machine viewed from the side. A disk test piece 30 coated with a test rust preventive paint was formed, and a 10 mm square block test piece 31 was pressed against the disk test piece 30 by imitating a rubber belt with a surface pressure of 0.5 kgf / cm ^2. In this state, the disk test piece 30 was rotated so that the sliding speed with respect to the block test piece 31 was 4 m / s by imitating the conveyor speed, and the friction coefficient of the coating film of the disk test piece 30 was measured.

  FIG. 5A to FIG. 5D show the friction test results.

As a result, as shown in FIG. 5A, the alkyd resin has a low coefficient of friction of 0.24 to 0.40 (specific wear amount 2.1 to 3.6 × 10 ⁻⁸ mm ³ / N · mm). It turned out to be friction.

FIG. 5 (b) shows the results of the conventional red lead zinc, with a friction coefficient of 0.726 to 1.165 (specific wear amount 24 × 10 ⁻⁸ mm ³ / N · mm). Met.

FIG. 5C shows the result of the modified epoxy resin, and the friction coefficient was 0.64 to 1.3 (specific wear amount 78 × 10 ⁻⁸ mm ³ / N · mm).

FIG.5 (d) shows the result of an organic zinc rich primer, and a friction coefficient is 0.3-0.60 (specific abrasion amount 11.2-15.4 * 10 < ^-8 > mm < ³ > / N * mm). )Met.

  From the test results of the friction coefficient, it can be seen that the friction coefficient of the alkyd resin is low and at the same time the wear amount is small.

  However, when looking at the friction coefficient, the organic zinc rich primer (see FIG. 5 (d)) is 0.3 to 0.60, and the friction coefficient is smaller than the lead zinc zinc (see FIG. 5 (b)), and the amount of wear. Therefore, it seems that the sliding performance will be better when used as a protective layer of trough structure than using leaded zinc, but actually it is worse than using leaded zinc. It was confirmed.

  As a result of examining this cause, it was considered that the surface roughness of the protective layer had an effect, and the surface roughness of these anticorrosive paints was measured.

  6 (a) to 6 (d) show the results of the surface roughness. FIG. 6 (a) shows the alkyd resin of the present invention, FIG. 6 (b) shows the lead tanned zinc, FIG. 6 (c). ) Shows the modified epoxy resin, and FIG. 6D shows the surface roughness of the organic zinc rich primer. The vertical scale in the figure is different in roughness depending on the paint, and accordingly, one vertical cell is shown in units of 2, 10, and 20 μm according to the roughness.

  As can be seen from FIGS. 5 to 6, the surface roughness of the alkyd resin of FIG. 6A is centerline average roughness Ra = 2.599 μm, ten-point average height Rz = 19.95 μm, FIG. ) Lead galvanized, Ra = 3.976 μm, Rz = 31.50 μm, modified epoxy resin of FIG. 6 (c), Ra = 0.8296 μm, Rz = 5.805 μm, organic zinc of FIG. 6 (d) With the rich primer, Ra = 1.492 μm and Rz = 12.05 μm.

  From this surface roughness, the surface roughness of lead tanned zinc is the roughest, followed by alkyd resin, organic zinc rich primer, and modified epoxy resin.

  Considering the friction coefficient and surface roughness of Pedang Zinc and Organic Zinc Rich Primer, the coefficient of friction is less than half that of Organic Zinc Rich Primer, and the surface roughness is the same as that of Organic Zinc Rich Primer. The sliding property as a protective layer is considered good, but the actual sliding property is poor. The modified epoxy resin also has substantially the same coefficient of friction as the red lead zinc, and the surface roughness is ¼ or less that of the red lead zinc, but is less slidable than the organic zinc rich primer.

  On the other hand, the alkyd resin of the present invention has a coefficient of friction smaller than that of red lead zinc or organic zinc rich primer, and the surface roughness is not rough than that of red lead zinc, but is sufficiently rougher than organic zinc rich primer. I understand.

  From the above results, considering the slidability of the red lead zinc, even if the friction coefficient with the rubber is high, the surface roughness is rough, that is, when the protective layer 20 of the trough 12 shown in FIG. Compressed air is supplied between the protective layer 20 and the conveyor belt 11, and the pressure of the air causes the conveyor belt 11 to float along with the conveyed object S. When considering contact with the conveyor belt 11, the surface roughness The rougher the air, the more the air is trapped and confined between the peaks and valleys, and it is considered that the contact pressure can be reduced by the air pressure and the sliding performance can be improved. Therefore, it was found that the red lead zinc improves the sliding characteristics with the surface roughness although the coefficient of friction with the rubber is poor.

  The alkyd resin of the present invention has a small coefficient of friction as shown in FIG. 5 (a), and the surface roughness is not as rough as that of red lead zinc, but is nearly twice that of organic zinc rich primer. It is thought that mobility improves.

  The reason why the surface roughness of this alkyd resin is rough is that, unlike reactive curing type paints such as organic zinc rich primer and modified epoxy resin, strong solvents such as ketones and ester solvents are used as solvents. Even in the above-mentioned “quick-drying loss one”, the alkyd resin / solvent (V / Sol) is 51% as much as the solvent, and in the process after application to the trough 12 and drying, the coating film is caused by minute shrinkage due to evaporation of the solvent. It is presumed that this is caused by lifting and roughening of the surface.

  The surface roughness Ra of the alkyd resin is 2.599 μm, but considering the surface roughness Ra of the red lead zinc, good sliding performance can be expected until the surface roughness Ra is 4.0 μm. Therefore, the surface roughness Ra is adjusted in the range of 2 to 4 μm by forming an organic zinc rich primer or other primer on the trough 12 as an underlayer, applying an alkyd resin on the underlayer and drying it. Is possible. In this case, if the thickness is 2 μm or less, the effect due to the surface roughness is small and sliding properties cannot be expected. If the thickness is 4 μm or more, the amount of wear increases due to the contact between the convex portion and the conveyor belt 11.

10 Air Floating Rollerless Conveyor 11 Conveyor Belt 12 Trough 20 Protective Layer

Claims (4)

  A conveyor trough structure in which a conveyor belt is supported by levitating air, wherein a protective layer is formed by applying an alkyd resin to the surface of the trough.   The conveyor trough structure according to claim 1, wherein an alkyd resin is dissolved in a solvent to form an alkyd resin paint, which is applied to the trough and then dried to form a protective layer.   The conveyor trough structure according to claim 1 or 2, wherein a base layer is formed on the trough, and an alkyd resin is applied on the base layer to form a protective layer.   The conveyor trough structure according to any one of claims 1 to 3, wherein the protective layer has a friction coefficient with rubber of 0.24 to 0.40 and a surface roughness Ra of 2 to 4 µm.

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