JP4558566B2 - Corrugated sheet steam heating device - Google Patents

Description

  The present invention relates to a steam heating apparatus for a corrugated cardboard sheet, which is heated indirectly with high-temperature and high-pressure steam by bringing the corrugated sheet of core paper, liner paper, single-sided corrugated cardboard sheet or double-sided corrugated cardboard sheet into contact.

  A corrugated cardboard manufacturing apparatus called a corrugating machine is, for example, a mill roll stand 4 for supplying a core paper 1, a first liner paper 2 and a second liner paper 3 as shown in FIG. 1 for explaining an embodiment of the present invention. First, the core paper 1 fed from the mill roll stand 4 with the single facer 7 is heated with the heating rolls 8a and 8b, and then waved with the pair of upper and lower step rolls 9a and 9b. Heating while forming into a shape and gluing to the top of one waveform with the gluing device 10, and heating the first liner paper 2 fed from the mill roll stand 5 with the heating rolls 11a and 11b, and then gluing The corrugated core paper 1 is pressed by a pressure belt 12 to form a single-sided cardboard sheet 13 in which the core paper 1 and the first liner paper 2 are bonded. The formed single-sided cardboard sheet 13 is heated by the heating rolls 14 a and 14 b, and is then glued to the other corrugated top of the core paper 1 by the gluing device 15, supplied to the double facer 16, and fed from the mill roll stand 6. After the second liner paper 3 to be heated is heated by the heating rolls 17a and 17b, it is bonded to the lower side of the single-sided cardboard sheet 13 to form a double-sided cardboard sheet 18.

  The double facer 16 includes an upstream heating part and a downstream cooling part. A heating box 19 is disposed at the lower part of the heating part, and a pressurizing device 20 is disposed at the upper part. The pressurizing device 20 presses the double-sided cardboard sheet 18 against the heating box 19 via the transport belt of the upper conveyor 21 provided across the heating part and the cooling part so as to feed the double-sided cardboard sheet 18. The second liner paper 3 and the single-sided cardboard sheet 13 are bonded uniformly. A lower conveyor 22 is disposed below the cooling part, and the bonded double-sided cardboard sheet 18 is sandwiched between the conveyor belts of the upper conveyor 21 and the lower conveyor 22 and is conveyed toward the outlet side while being cooled. The formed double-sided corrugated cardboard sheet 18 is slitted and scorer 23 provided on the discharge line on the outlet side of the double facer 16, subjected to width cutting and ruled line as necessary, and length-cut with a rotary cutter 24. , Stacked on the discharge end.

  The gluing device 10 for bonding the core paper 1 and the first liner paper 2 with the single facer 7 and the gluing device 15 for bonding the second liner paper 3 and the single-sided cardboard sheet 13 with the double facer 16 are starch paste. In order to promote the solidification of the starch paste and increase the adhesive strength, the corrugated sheets of the core paper 1, the liner papers 2, 3, the single-sided cardboard sheet 13, and the double-sided cardboard sheet 18 are Heating devices such as the respective heating rolls 8a, 8b, 11a, 11b, 14a, 14b, 17a, 17b, corrugated rolls 9a, 9b, and a heating box 19 are provided that are heated before or during bonding with glue. The corrugated rolls 9a and 9b also serve to prevent molding defects due to springback of the core paper 1 that is formed into a wave shape by heating.

  Corrugated cardboard sheet heating devices such as the above-mentioned heating rolls, corrugated rolls, and heating boxes are used for corrugated cardboard that supplies high-temperature and high-pressure steam to the inside of a hollow roll or box and contacts the outer surface thereof. Many steam heating apparatuses that indirectly heat the sheet with steam are used (see, for example, Patent Documents 1, 2, and 3). Patent Document 1 discloses a steam heating device employed in a heating roll, Patent Document 2 discloses a steam heating device employed in a heating roll and a corrugated roll, and Patent Document 3 discloses a steam heating device employed in a heating box. Each heating device is described. In addition, in what was described in patent document 1, the heating apparatus which sprays high temperature vapor | steam directly on liner paper is also used together.

  These steam heating apparatuses for corrugated board sheets are provided with a discharge path for discharging the heated steam from the inside of the roll or box. The steam after this heating partially condenses and becomes drainage, which causes a reduction in heating efficiency and heating unevenness.Therefore, in the steam discharge path, an orifice or A steam trap using a float valve is provided.

JP 61-270143 A (Fig. 1) Registered Utility Model No. 3061220 (Fig. 1) Japanese Utility Model Publication No.59-24498 (Fig. 1-3)

  The conventional steam heating apparatus for corrugated cardboard sheets provided with a steam trap in the steam discharge path described above is consumed for heating due to an increase in the feeding speed of the corrugated cardboard sheets, the width dimension or the basis weight of the base paper. If the amount of heat increases rapidly, the supply amount of high-temperature and high-pressure steam will be insufficient, and drainage that will increase rapidly due to condensation of steam after heating cannot be recovered quickly, resulting in insufficient heating of the cardboard sheet or uneven heating. There is a problem that occurs.

  If heating of the cardboard sheet is insufficient or uneven heating occurs, the heating roll, cardboard roll, heating box, etc. that heats the cardboard sheet before or during bonding with the starch paste of the gluing device The solidification of starch paste is not sufficiently promoted, resulting in poor adhesion such as insufficient adhesive strength and uneven adhesion of the cardboard sheet. Further, in the corrugated roll that is heated while forming the core paper into a corrugated shape, the corrugated shape of the core paper due to the spring back is likely to be generated, and the defective adhesion is more likely to occur due to this forming failure.

  Accordingly, an object of the present invention is to provide a steam heating apparatus for corrugated board sheets that does not cause insufficient heating or uneven heating even when the amount of heat consumed for heating increases rapidly.

  In order to solve the above-mentioned problems, the present invention brings a corrugated sheet of any one of core paper, liner paper, single-sided cardboard sheet or double-sided cardboard sheet to be fed into contact with the outer surface of the hollow body. In the steam heating apparatus for corrugated cardboard sheets, in which high-temperature and high-pressure steam is supplied to the inside of the corrugated board to indirectly heat the contacted corrugated cardboard sheets with steam, the steam after heating the corrugated cardboard sheets A discharge path forcibly discharging from the cardboard is provided, and an opening / closing valve is provided in the discharge path, and the discharge path is provided based on at least one of the feeding speed, width dimension, and basis weight of the cardboard sheet. The on-off valve is controlled so that new high-temperature and high-pressure steam is promptly supplied to the inside of the hollow body even if the amount of heat consumed for heating the corrugated board sheet increases rapidly. It was adopted formed.

  In other words, a discharge path for forcibly discharging the steam after heating the cardboard sheet from the inside of the hollow body is provided, and an opening / closing valve is provided in the discharge path so that the feeding speed, width dimension and basis weight of the cardboard sheet Based on at least one of the above information, the on-off valve provided in the discharge path is controlled, and the amount of heat consumed for heating is drastically increased by increasing the feeding speed, width dimension, or basis weight of the corrugated sheet to be fed. Even if the temperature increases, the steam whose temperature has decreased after heating and the condensate of this steam are forcibly discharged from the discharge path quickly by controlling the on-off valve, and new high-temperature and high-pressure steam is generated inside the hollow body. Was supplied quickly so as not to cause insufficient heating or uneven heating.

  By using the steam heating device to heat the cardboard sheet before or during bonding with starch paste, solidifying the starch paste is promoted uniformly, insufficient adhesive strength of the cardboard sheet, uneven bonding, etc. It is possible to prevent poor adhesion.

  By using the steam heating device to heat the core paper bonded to the liner paper with starch paste while forming it into a wave shape, it prevents adhesion failure and also causes poor core paper molding due to springback. Can be prevented.

  The steam heating apparatus for corrugated board sheet according to the present invention is provided with a discharge path for forcibly discharging steam after heating the cardboard sheet from the inside of the hollow body, and an opening / closing valve is provided in the discharge path, The on-off valve provided in the discharge path is controlled based on at least one of the feeding speed, width dimension and basis weight information of the paper, and the feeding speed, width dimension or basis weight of the corrugated sheet to be fed is increased. Even if the amount of heat consumed for heating increases suddenly, the steam whose temperature has decreased after heating and the drain condensed by this steam are forcibly discharged from the discharge path quickly by controlling the on-off valve, Since new high-temperature and high-pressure steam is promptly supplied into the hollow body, it is possible to prevent insufficient heating and uneven heating.

  By making the steam heating device heat the cardboard sheet before or during bonding with the starch paste, the starch paste can be solidified uniformly, resulting in insufficient adhesion of the cardboard sheet, uneven bonding, etc. Adhesion failure can be prevented.

  By using the steam heating device to heat the core paper, which is bonded to the liner paper and starch paste, while forming it into a corrugated shape, it prevents adhesion failure and prevents core paper formation failure due to springback. can do.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a corrugating machine employing a corrugated sheet steam heating apparatus according to the present invention. This corrugating machine has mill roll stands 4, 5, 6 for supplying the core paper 1, the first liner paper 2 and the second liner paper 3, respectively. First, the single facer 7 feeds from the mill roll stand 4. The core paper 1 to be heated is heated with heating rolls 8a and 8b, and then heated while being formed into a wave shape with a pair of upper and lower corrugated rolls 9a and 9b, and glued to the top of one waveform with a gluing device 10, The first liner paper 2 fed from the mill roll stand 5 is heated by the heating rolls 11a and 11b, and then pressed to the corrugated core paper 1 by the pressure belt 12 so that the core paper 1 and the first core paper 1 A single-sided cardboard sheet 13 to which a liner paper 2 is bonded is formed. The formed single-sided cardboard sheet 13 is heated by the heating rolls 14a and 14b, and is then glued to the other corrugated top of the core paper 1 by the gluing device 15 and supplied to the double facer 16 and fed from the mill roll stand 6 After the second liner paper 3 to be heated is heated by the heating rolls 17a and 17b, it is bonded to the lower side of the single-sided cardboard sheet 13 to form a double-sided cardboard sheet 18.

  The double facer 16 includes an upstream heating part and a downstream cooling part. A heating box 19 is disposed at the lower part of the heating part, and a pressurizing device 20 is disposed at the upper part. The pressurizing device 20 presses the double-sided cardboard sheet 18 against the heating box 19 via the transport belt of the upper conveyor 21 provided across the heating part and the cooling part so as to feed the double-sided cardboard sheet 18. The second liner paper 3 and the single-sided cardboard sheet 13 are bonded uniformly. A lower conveyor 22 is disposed below the cooling part, and the bonded double-sided cardboard sheet 18 is sandwiched between the conveyor belts of the upper conveyor 21 and the lower conveyor 22 and is conveyed toward the outlet side while being cooled. The formed double-sided corrugated cardboard sheet 18 is slitted and scorer 23 provided on the discharge line on the outlet side of the double facer 16, subjected to width cutting and ruled line as necessary, and length-cut with a rotary cutter 24. , Stacked on the discharge end.

  The gluing device 10 for bonding the core paper 1 and the first liner paper 2 with the single facer 7 and the gluing device 15 for bonding the second liner paper 3 and the single-sided cardboard sheet 13 with the double facer 16 are water-soluble. Starch paste is used, and in order to promote the solidification of the starch paste and increase the adhesive strength, the corrugated sheets of the core paper 1, the liner papers 2 and 3, the single-sided cardboard sheet 13 and the double-sided cardboard sheet 18 are used. Steam heating according to the present invention is applied to each of the heating rolls 8a, 8b, 11a, 11b, 14a, 14b, 17a, 17b, the corrugated rolls 9a, 9b, and the heating box 19, which are heated before or during bonding with starch paste. A device is provided.

  2 and 3 show, as a representative example, an upper roll 9a that heats the core paper 1 bonded to the first liner paper 2 with the single facer 7 while forming it into a wave shape with the lower roll 9b. Shows the steam heating system adopted. This steam heating apparatus supplies a core paper 1 that supplies high-temperature and high-pressure steam from a boiler (not shown) into a hollow body through a supply path 31 and contacts the outer surface of the upper roll 9a with steam. Indirect heating is performed, and steam whose temperature has decreased after heating and drain condensed from the steam are discharged from the discharge path 32. Although illustration is omitted, the steam heating device of the lower roll 9b has the same configuration.

  The discharge path 32 branches into a discharge path 32 a provided with a steam trap 33 and a discharge path 32 b provided with an electromagnetic valve 35 as an on-off valve controlled by a controller 34. The discharge path 32b forcibly discharges steam and drain after heating when the electromagnetic valve 35 is opened. The steam trap 33 discharges the accumulated drain by operating the float valve when a predetermined amount of drain accumulates in the upper roll 9a, and the two branched discharge paths 32a and 32b are: The same collection path 36 is connected.

  The controller 34 receives the feed speed V, width dimension W and basis weight T of the core paper 1 fed to the single facer 7. The controller 34 receives these feed speed V and width dimension. When either W or basis weight T exceeds a preset threshold value for each, the electromagnetic valve 35 is opened, the steam and drain after the core paper 1 is heated is forcibly discharged, and the supply path New high-temperature and high-pressure steam is supplied from 31 to the inside of the upper roll 9a.

  As an example, the controller 34 controls the electromagnetic valve 35 to heat the core paper 1 fed to the single facer 7 while forming it into a wave shape, and the high temperature and high pressure steam supplied to the upper roll 9a. The change of the supply amount S was measured. As a comparative example, a change in the supply amount S of high-temperature and high-pressure steam when the solenoid valve 35 was kept closed without being controlled was also measured. Regarding the single-sided corrugated cardboard sheet 13 bonded under the heating conditions of these examples and comparative examples, the bonding state between the core paper 1 and the first liner paper 2 was also investigated.

4 (a) and 4 (b) show changes in the supply amount S of high-temperature and high-pressure steam corresponding to changes in the feeding speed V and basis weight T of the core paper 1 in the above-described examples and comparative examples, respectively. . In the embodiment shown in FIG. 4 (a), when the feed speed V of the core paper 1 exceeds 270 m / min, and when the basis weight T of the core paper 1 exceeds 150 g / m ² , the solenoid valve 35 is The steam supply amount S is rapidly increased. Further, the single-sided cardboard sheet 13 for which the adhesion state was investigated also had the core paper 1 and the first liner paper 2 well bonded over the entire length, and the corrugated shape of the core paper 1 was also well formed.

  On the other hand, in the comparative example shown in FIG. 4B, even when the feeding speed V and the basis weight T of the core paper 1 are increased, the steam supply amount S is increased only slowly. Adhesion failure between the core paper 1 and the first liner paper 2 was detected on the single-sided cardboard sheet 13 where the feeding speed V and the basis weight T of the core paper 1 increased. The reason for this is that even if the amount of heat consumed for heating increases rapidly due to an increase in the feeding speed V or the basis weight T, the steam trap 33 will not discharge unless the drain has accumulated to some extent inside the upper roll 9a. This is because the supply amount S increases only slowly, resulting in insufficient heating and uneven heating.

  From the results of these examples and comparative examples, the steam heating device according to the present invention rapidly increases the supply amount of high-temperature and high-pressure steam even if the amount of heat consumed for heating increases rapidly. Thus, it was confirmed that insufficient heating and uneven heating could be eliminated and adhesion defects that had occurred in the past could be prevented. In this embodiment, the solenoid valve of the discharge path is controlled in accordance with the increase in the feeding speed and basis weight of the core paper. However, the solenoid valve may be controlled in accordance with the increase in the width dimension of the core paper. it can. In addition, in each heating roll or heating box that heats other cardboard sheets such as each liner paper, single-sided cardboard sheet, double-sided cardboard sheet, etc., the same control prevents the occurrence of insufficient heating and uneven heating. be able to.

  In the embodiment described above, the conventional discharge path provided with the steam trap is provided in the steam discharge path after heating the corrugated sheet, but the discharge path provided with the steam trap is omitted, and an on-off valve is provided. It can also be a forced discharge route only.

The schematic front view which shows the corrugating machine which employ | adopted the steam heating apparatus of the cardboard sheet | seat based on this invention FIG. 1 is an enlarged front view showing the vicinity of the single facer of FIG. Piping system diagram showing the steam heating device used in the upper roll in FIG. The graph which shows the change of the supply_amount | feed_rate S of the steam in the Example in the steam heating apparatus of FIG. The graph which shows the change of the supply amount S of the steam in the comparative example of Fig.4 (a)

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Core paper 2, 3 Liner paper 4, 5, 6 Mill roll stand 7 Single facer 8a, 8b Heating roll 9a, 9b Corrugated roll 10 Gluing apparatus 11a, 11b Heating roll 12 Pressure belt 13 Single side corrugated cardboard sheet 14a, 14b Heating roll 15 Gluing device 16 Double facer 17a, 17b Heating roll 18 Double-sided cardboard sheet 19 Heating box 20 Pressing device 21, 22 Conveyor 23 Slitter / scorer 24 Rotary cutter 31 Supply path 32, 32a, 32b Discharge path 33 Steam Trap 34 Controller 35 Solenoid valve 36 Collection path

Claims (3)

  The core paper, liner paper, single-sided cardboard sheet or double-sided cardboard sheet to be fed is brought into contact with the outer surface of the hollow body, and high-temperature and high-pressure steam is supplied into the hollow body, A corrugated sheet steam heating apparatus for indirectly heating a corrugated cardboard sheet with steam is provided with a discharge path for forcibly discharging the steam after heating the corrugated sheet from the inside of the hollow body. An on-off valve is provided in the path, and the on-off valve provided in the discharge path is controlled based on information on at least one of a feeding speed, a width dimension, and a basis weight of the cardboard sheet to heat the cardboard sheet. Even if the amount of heat consumed increases rapidly, new high-temperature and high-pressure steam is rapidly supplied into the hollow body, and the cardboard sheet steam is characterized in that Heat equipment.   The steam heating apparatus for corrugated board according to claim 1, wherein the steam heating apparatus heats the corrugated board sheet before or during bonding with starch paste.   The steam heating apparatus for corrugated cardboard sheets according to claim 2, wherein the steam heating apparatus heats the core paper bonded to the liner paper with starch paste while forming it into a corrugated shape.

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