Hydrophobic structure of steam-heated rollers in corrugated cardboard production line

Abstract

A steam heating roller hydrophobic structure for a corrugated cardboard production line comprises a steam heating roller (1) and a siphon tube arranged inside the steam heating roller (1), characterized in that a spiral guide plate (2) is arranged inside the steam heating roller (1) and moves synchronously with the steam heating roller (1), and the outer spiral line of the spiral guide plate (2) is in contact with or connected to the inside of the steam heating roller (1). The present invention relates to the field of steam heating rollers, and in particular to a steam heating roller hydrophobic structure for a corrugated cardboard production line. The present invention has the advantages of changing the structure of the traditional steam heating roller in which the condensed water formed after the steam condenses is naturally adsorbed in the inner cavity of the cylinder body. By innovatively designing the spiral guide plate, the rotation direction of the spiral guide plate is designed according to the rotation direction of the steam heating roller.

Description

Technical Field

[0001] The invention relates to the field of steam heating rollers, and in particular to a steam heating roller hydrophobic structure used in a corrugated board production line. Background Art

[0002] At present, in the corrugated paper forming process, the steam heating roller (specific structure includes the hot cylinder on the corrugator line and the corrugating roller) needs to be at a certain temperature so that the base paper can be preheated by the steam heating roller and pressed into a corrugated shape to produce corrugated paperboard;

[0003] Steam heating is mainly used to heat the steam heating roller. Steam is introduced into the inner cavity of the steam heating roller to heat the cylinder body and heat the base paper. The steam condenses into water after heat exchange, and the condensed water is discharged from the steam heating roller through a siphon to ensure efficient heat exchange of the steam heating roller.

[0004] However, there are the following problems: 1) Since the condensed water exists in the entire cylinder cavity, the condensed water film is very thin, and there is a certain distance between the siphon tube and the inner cavity surface, the condensed water cannot be sucked out. The condensed water film covers the inner surface of the cylinder, forming thermal resistance, reducing the heat exchange between steam and the steam heating roller, causing the outer surface temperature of the steam heating roller to drop, resulting in problems such as the cardboard corrugation not being formed and affecting the vehicle speed; 2) When the steam heating roller stops running, the siphon tube is at a certain distance from the inner surface of the steam heating roller cavity, so the condensed water cannot be sucked out and accumulates at the bottom of the steam heating roller. This causes the steam heating roller to deform and bend due to the temperature difference between the upper and lower parts, causing uneven heating of the base paper; for the corrugated roller in the steam heating roller, it will cause a portion of waste single corrugated paper to be produced when it is restarted. Summary of the invention

[0005] The purpose of the present invention is to provide a steam heating roller hydrophobic structure for a corrugated board production line in order to overcome the above-mentioned shortcomings.

[0006] The invention comprises a steam heating roller and a siphon tube arranged inside the steam heating roller. A spiral guide plate which moves synchronously with the steam heating roller is arranged inside the steam heating roller, and the outer spiral line of the spiral guide plate is in contact with or connected to the inside of the steam heating roller.

[0007] The cross-sectional area of ​​the spiral guide vane is one of a rectangular, a trapezoidal or an arc shape.

[0008] The outlet of the spiral guide plate corresponds to the inlet position of the siphon tube.

[0009] The design method of spiral guide vane is as follows:

[0010] 1) Calculate the maximum flow rate of condensed water according to the condensed water load of the steam heating roller;

[0011] υ=Q / ρ / (π*d²*10-6 / 4)*ζ / 3600,

[0012] Where, υ is the flow velocity of condensed water in the steam heating roller m / s,

[0013] Q is the condensate load kg / h,

[0014] ρ is the density of condensed water kg / m³,

[0015] d is the diameter of the siphon tube, mm,

[0016] ζ is the condensate discharge coefficient;

[0017] 2) Convert the running speed into the rotation speed of the steam heating roller,

[0018] n=V / 60 / π / D*1000*γ,

[0019] Wherein, n is the rotation speed r / s of the steam heating roller 1,

[0020] V is the running speed of the tile line m / min,

[0021] D is the diameter of the steam heating roller in mm;

[0022] γ is the corrugation coefficient;

[0023] 3) Calculate the minimum pitch of the spiral guide vane,

[0024] p=υ / n *1000,

[0025] Where p is the pitch of the spiral guide vane in mm,

[0026] υ is the flow velocity of condensed water in the steam heating roller m / s;

[0027] n is the rotation speed of the steam heating roller in r / s;

[0028] 4) Helix angle

[0029] θ=arctan(p / (π*D))*180 / π,

[0030] Where θ is the helix angle,

[0031] p is the pitch of the spiral guide vane in mm,

[0032] D is the diameter of the steam heating roller in mm.

[0033] ζ is the condensate discharge coefficient, which is 3-5.

[0034] The advantages of the present invention are: it changes the structure of the condensed water formed after the steam condenses in the traditional steam heating roller and is naturally adsorbed in the inner cavity of the cylinder. Through the innovative design of the spiral guide plate, the rotation direction of the spiral guide plate is designed according to the rotation direction of the steam heating roller, so that when the steam heating roller is running, the condensed water is just drained to one end of the siphon pipe installed in the cylinder body along the movement direction of the steam heating roller, so that the siphon pipe can conveniently discharge the condensed water from the roller body. Thereby solving the problem of reduced heat transfer efficiency and deformation of the tile roller during shutdown caused by the accumulation of condensed water in the entire cylinder body. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a schematic diagram of the structure of the present invention.

[0037] Figure 2 Schematic diagram of the structure of the spiral guide vane 2. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0039] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0041] In the description of the embodiments of the present invention, it should be noted that if the terms "upper", "lower", "inner", "outer", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the product of the invention is usually placed when in use. This is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, if the terms "first", "second", etc. appear in the description of the present invention, they are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0042] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "setting" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0043] As shown in the figure, the present invention includes a steam heating roller 1 and a siphon tube arranged inside the steam heating roller 1. A spiral guide plate 2 is arranged inside the steam heating roller 1 and moves synchronously with the steam heating roller 1, and the outer spiral line of the spiral guide plate 2 is in contact with or connected to the inside of the steam heating roller 1.

[0044] The cross-sectional area of ​​the spiral guide vane 2 is one of a rectangular, a trapezoidal or an arc shape.

[0045] The outlet of the spiral guide plate 2 corresponds to the inlet position of the siphon tube.

[0046] The design method of spiral guide vane 2 is as follows:

[0047] 1) Calculate the maximum flow rate of condensed water according to the condensed water load of the steam heating roller 1;

[0048] υ=Q / ρ / (π*d²*10 -6 / 4)*ζ / 3600,

[0049] Wherein, υ is the flow velocity of condensed water in the steam heating roller 1 in m / s,

[0050] Q is the condensate load kg / h,

[0051] ρ is the density of condensed water kg / m³,

[0052] d is the diameter of the siphon tube, mm,

[0053] ζ is the condensate discharge coefficient;

[0054] 2) Convert the running speed into the rotation speed of the steam heating roller 1,

[0055] n=V / 60 / π / D*1000*γ,

[0056] Wherein, n is the rotation speed r / s of the steam heating roller 1,

[0057] V is the running speed of the tile line m / min,

[0058] D is the diameter of the steam heating roller 1 mm;

[0059] γ is the corrugation coefficient;

[0060] 3) Calculate the minimum pitch of spiral guide vane 2,

[0061] p=υ / n *1000,

[0062] Wherein, p is the pitch of the spiral guide vane 2 in mm,

[0063] υ is the flow velocity of condensed water in the steam heating roller 1 m / s;

[0064] n is the rotation speed of the steam heating roller 1 in r / s;

[0065] 4) Helix angle

[0066] θ=arctan(p / (π*D))*180 / π,

[0067] Where θ is the helix angle,

[0068] p is the pitch of the spiral guide vane 2 in mm,

[0069] D is the diameter of the steam heating roller 1 mm.

[0070] ζ is the condensate discharge coefficient, which is 3-5.

[0071] Working principle of spiral guide vane 2: Condensate formed after steam condensation exists in the steam heating roller 1. When the steam heating roller 1 runs at high speed during the production process, the condensate in the steam heating roller 1 also rotates accordingly, and gradually gathers toward the front of the cylinder body along the guidance of spiral guide vane 2, forming a thicker condensate layer in the front of the steam heating roller 1, which reduces the thickness of the condensate wall layer in other parts of the steam heating roller 1 and improves the heat transfer efficiency; at the same time, it is beneficial for the siphon to discharge the condensate and reduce the accumulation of condensate in the steam heating roller 1.

[0072] Example 1: Smaller hot cylinder, high speed;

[0073] The hot cylinder condensate load Q is calculated as 250kg / h, the steam pressure is 10bar, the corresponding condensate density ρ is 886.9kg / m³, the siphon diameter d is 20mm, the condensate displacement coefficient ζ is 5, and the condensate flow rate in the hot cylinder is calculated.

[0074] υ=Q / ρ / (π*d²*10 -6 / 4)*ζ / 3600

[0075] =250 / 886.9 / (3.14*20*20*10 -6 / 4)*5 / 3600=1.25m / s

[0076] The running speed V of the corrugator line is 350m / min; the inner diameter of the preheating cylinder is 380mm; the corrugation coefficient γ is 1.38, and the rotation speed of the preheating cylinder is calculated to be n=V / 60 / π / D 内 *1000*γ

[0077] =350 / 60 / 3.14 / 380 / 1000*1.38=6.1 r / s

[0078] Pitch of spiral guide vane 2

[0079] p=υ / n *1000=1.25 / 6.1*1000=204.2mm

[0080] Helix Angle

[0081] θ=arctan(p / (π*D 内 ))*180 / π

[0082] =arctan(204.2 / (3.14*380))*180 / 3.14=9.7°

[0083] Example 2: Smaller hot cylinder, low speed;

[0084] The condensate load Q of the preheating cylinder is calculated as 100kg / h, the steam pressure is 10bar, the corresponding condensate density ρ is 886.9kg / m³, the siphon diameter d is 20mm, the condensate displacement coefficient ζ is 5, and the condensate flow rate in the hot cylinder is calculated.

[0085] υ=Q / ρ / (π*d²*10 -6 / 4)*ζ / 3600

[0086] =100 / 886.9 / (3.14*20*20*10 -6 / 4)*5 / 3600=0.5m / s

[0087] The running speed V of the corrugator line is 50m / min; the inner diameter of the preheating cylinder is 380mm; the corrugation coefficient γ is 1.38, and the rotation speed of the preheating cylinder is calculated to be n=V / 60 / π / D 内 *1000*γ

[0088] =50 / 60 / 3.14 / 380 / 1000*1.38=0.87 r / s

[0089] Pitch of spiral guide vane 2

[0090] p=υ / n *1000=0.5 / 0.87*1000=571.9 mm

[0091] Helix Angle

[0092] θ=arctan(p / (π*D 内 ))*180 / π

[0093] =arctan(571.9 / (3.14*380))*180 / 3.14=25.6°

[0094] Example 3: Larger hot cylinder, high speed;

[0095] The condensate load Q of the preheating cylinder is calculated as 550kg / h, the steam pressure is 10bar, the corresponding condensate density ρ is 886.9kg / m³, the siphon diameter d is 20mm, the condensate displacement coefficient ζ is 3, and the condensate flow rate in the hot cylinder is calculated.

[0096] υ=Q / ρ / (π*d²*10 -6 / 4)*ζ / 3600

[0097] =550 / 886.9 / (3.14*20*20*10 -6 / 4)*3 / 3600=1.64m / s

[0098] The running speed V of the corrugator line is 350m / min; the inner diameter of the preheating cylinder is 1000mm; the corrugation coefficient γ is 1.38, and the rotation speed of the preheating cylinder is calculated to be n=V / 60 / π / D 内 *1000*γ

[0099] =350 / 60 / 3.14 / 1000 / 1000*1.38=2.38 r / s

[0100] Pitch of spiral guide vane 2

[0101] p=υ / n *1000=1.64 / 2.38*1000=693.3 mm

[0102] Helix Angle

[0103] θ=arctan(p / (π*D 内 ))*180 / π

[0104] =arctan(693.3 / (3.14*1000))*180 / 3.14=12.5°

[0105] Example 4: Larger hot cylinder, low speed;

[0106] The condensate load Q of the preheating cylinder is calculated as 160kg / h, the steam pressure is 10bar, the corresponding condensate density ρ is 886.9kg / m³, the siphon diameter d is 20mm, the condensate displacement coefficient ζ is 3, and the condensate flow rate in the hot cylinder is calculated.

[0107] υ=Q / ρ / (π*d²*10 -6 / 4)*ζ / 3600

[0108] =160 / 886.9 / (3.14*20*20*10 -6 / 4)*3 / 3600=0.47m / s

[0109] The running speed V of the corrugator line is 100m / min; the inner diameter of the preheating cylinder is 1000mm; the corrugation coefficient γ is 1.38, and the rotation speed of the preheating cylinder is calculated to be n=V / 60 / π / D 内 *1000*γ

[0110] =100 / 60 / 3.14 / 1000 / 1000*1.38=0.68 r / s

[0111] Pitch of spiral guide vane 2

[0112] p=υ / n *1000=0.47 / 0.68*1000=705 .9mm

[0113] Helix Angle

[0114] θ=arctan(p / (π*D 内 ))*180 / π

[0115] =arctan(705.9 / (3.14*1000))*180 / 3.14=12.7°.

Claims

1. A steam heating roller water-repellent structure for a corrugated board production line, comprising a steam heating roller (1) and a siphon arranged inside the steam heating roller (1), characterized in that A spiral guide plate (2) is arranged inside the steam heating roller (1) and moves synchronously with the steam heating roller (1), and an outer spiral line of the spiral guide plate (2) is in contact with or connected to the inside of the steam heating roller (1); The design method of the spiral guide vane (2) is as follows: 1) Calculate the maximum flow rate of condensate according to the condensate load of the steam heating roller (1); u=Q / ρ / (π*d²*10 -6 / 4)*ζ / 3600, Wherein, υ is the flow velocity of the condensed water in the steam heating roller (1) in m / s, Q is the condensate load kg / h, ρ is the density of condensed water kg / m³, d is the diameter of the siphon tube, mm, ζ is the condensate discharge coefficient; 2) converting the running speed into the rotation speed of the steam heating roller (1); n=V / 60 / π / D*1000*γ, Wherein, n is the rotation speed r / s of the steam heating roller (1), V is the running speed of the tile line m / min, D is the diameter of the steam heating roller (1) in mm; γ is the corrugation coefficient; 3) Calculate the minimum pitch of the spiral guide vane (2); p=υ / n *1000, Wherein, p is the pitch of the spiral guide vane (2) in mm, υ is the flow velocity of condensed water in the steam heating roller (1) in m / s; n is the rotation speed of the steam heating roller (1) in r / s; 4) Helix angle; θ=arctan(p / (π*D))*180 / π, Where θ is the helix angle, p is the pitch of the spiral guide vane (2) in mm, D is the diameter of the steam heating roller (1) in mm.

2. The hydrophobic structure of the steam heating roller of the corrugated board production line according to claim 1, characterized in that: The cross-sectional area of ​​the spiral guide vane (2) is one of a rectangular, a trapezoidal or an arc shape.

3. The hydrophobic structure of the steam heating roller of the corrugated board production line according to claim 1, characterized in that: The outlet of the spiral guide plate (2) corresponds to the inlet position of the siphon tube.

4. The hydrophobic structure of the steam heating roller of the corrugated board production line according to claim 1, characterized in that: ζ is the condensate discharge coefficient, which is 3-5.

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