JP4048441B2 - Pulp dewatering machine - Google Patents

Description

The present invention relates to a pulp dewatering machine having a net dewatering device, a press device, a drying device, and a cutting machine for pulp belt .

  A pulp dehydrator of the above kind is already known. According to the prior art, the maximum running speed in such machines for papermaking is in the range of 50-70 m / min.

  The upper speed limit of such a machine is largely based on two factors: the dewatering capacity of the screen dewatering device and the speed of the cutter. In the production of paper, a long net is generally used as a net dewatering device, and its length is important for the dewatering capacity. Although the dewatering capacity is related to the length of the long net, even if the long net is extended by a fractional m, the speed only increases by a fractional m / min.

  A normal cutting machine does not allow higher speeds than those previously mentioned as well. To obtain higher speeds, it would be possible to stack the pulp sheets in a cutter, but this is not possible due to the surface roughness of the pulp sheets.

  The problem underlying the present invention is to provide a pulp dehydrator that allows a significant increase in speed in the pulp dewaterer to date.

This object is achieved in the first mentioned type of pulp dewatering machine, by the network dewatering device is Tsu consists circle network device with four suction network is solved. The circular net allows for a significantly higher speed in the range of about 90 m / min. Moreover, special so-called suction nets enable speeds up to 450 m / min. In order to obtain a high dewatering capacity, the circular net device has four suction nets. In order to be able to dewater the pulp band from both sides, the circular net device can further have a reverse press and a dandy roll press.

  To further increase the speed, the pressing device can have at least one glossy cylinder, which acts as a single-sided glossy cylinder on the ground and polished surface, and has a unique surface on the contact side of the circulating pulp band. Give quality. The one-side glossiness of the pulp band is already sufficient to allow the pulp sheets to be stacked in a cutter. At least one glossy cylinder can co-operate with one or more suction press rolls to further improve the dewatering capacity.

  In order to give gloss to both surfaces of the pulp band, two gloss cylinders can advantageously be provided. By improving the surface quality of the pulp band on both sides, it is possible to stack the pulp sheets perfectly and without problems in the cutting machine. Thereby, a speed in the range of 150 to 160 m / min can be obtained.

  Both glossy cylinders can have a drying covering to aid in subsequent drying.

  After pressing and glossing, the pulp band is led to a drying device for further drying. The drying device can conveniently have at least one drying tower, and the at least one drying tower can be provided with a baffle nozzle. The at least one drying tower can be followed by a rocking tower that heats or cools the pulp band. A cooling tower can then be provided, which ensures that the pulp strip is cooled slightly below room temperature before entering the cutting machine, thereby avoiding static charges in the cutting machine, Otherwise, the rocking vessel may be damaged.

  In the second preferred embodiment, the drying device has a pulp band drying passage provided horizontally. The drying device advantageously has three parts, in which the drying with hot air takes place in the first part. The second part of the drying passage can be provided in the same way as the rocking tower for heating or cooling and the last part for cooling the pulp band. The drying device can advantageously have an automatic belt edge control.

  A dancer roll can be provided between the last glossy cylinder and the drying device, thereby preventing longitudinal shrinkage of the pulp band due to overdrying.

  In order to guide the band tip in the center, a clamping rod that can be electromagnetically fixed to the band tip can be provided. This clamping bar is attached to two side guide chains. Further, a cut-off frame having a cut-off swing piece that can swing 45 ° on both sides can be provided between the last glossy cylinder and the drying device in order to cut the band tip to a width of about 500 to 1000 mm. To guide the band edge, easily movable rocking links can be provided, and these sliding links can be brought from a 45 ° position to a 90 ° position and once the 90 ° position is reached. Has a contact switch to start dropping the upper clamping machine.

  Another advantage arises if the demagnetization section after the last cooling tower is provided with an upper clamping bar removal device. The upper clamping bar can be returned to the front of the first drying tower by a crane that is subsequently dropped onto the receiving machine.

  In order to reduce the load of the cutting machine's retracting press when the belt is left on the machine during long machine stops or to prevent re-joining of the belt, the full width clamping press is connected to the last cooling tower. It can be provided between the cutting machine.

  In order to facilitate the work of the operator, the pulp dewatering machine can have at least a digital measurement and display device for the residual humidity and temperature of the pulp band, at least in front of the entrance of the cutting machine 1.

  A preferred embodiment of a pulp dehydrator according to the invention is described below with reference to the drawings.

  FIG. 1 schematically shows a pulp dewatering machine 10 according to the present invention having a net dewatering device 20, a press device 30, a drying device 40 and a cutting machine 50. The net dewatering device 20 has a circular net device having four suction nets 21, 22, 23 and 24, a reverse press 25 and a dandy roll press 26. The pulp band 11 first passes through the suction nets 24 to 21 and then led to the reversing press 25 where it is reversed and led again through the suction nets 21 to 24 to dehydrate the other side of the band, Then, it passes through the dandy roll press 26 and is further guided to the press device. The press device 30 has two glossy cylinders 31 and 32, and two suction press rolls 33 and 34 are provided in the glossy cylinder 31 among these glossy cylinders in order to improve the dewatering capability. Both gloss cylinders 31 and 32 are provided with drying covers 35 and 36 to assist in subsequent drying. If two gloss cylinders 31 and 32 are used in an S-shaped loop, processing on both sides of the pulp band 11 is possible, and the pulp band is not only dehydrated, but is given a gloss, so that the sheet is cut in the cutting machine 50. A reliable stacking of 150 to 160 m / min is thus ensured. The pressing device 30 can have only one gloss cylinder instead of two. In that case, only one side of the strip is glossed, but in some circumstances this may be sufficient to obtain high speeds by allowing sheets to be stacked as well.

  From the press device 30, the pulp band 11 is guided to a drying device 40 having a drying tower 41, a swinging tower 42 for heating and cooling, and a cooling tower 43 for cooling the pulp band 11. Drying in the drying tower 41 is performed by a baffle nozzle not shown in the figure. The rocking tower 42 is used for selectively heating or cooling the pulp band 11. The last tower 43 is used only for cooling, whereby the pulp strip 11 is cooled slightly below room temperature before entering the cutting machine 50 to avoid static charges in the cutting machine 50. The cutting machine 50 includes, in a standardized form, a waste gate 51 and a switch 52 for packaging or deposition operation.

  FIG. 2 schematically shows a second embodiment of a pulp dewatering machine 10 'according to the invention having a net dewatering device 20', a pressing device 30 ', a drying device 45 and a cutting machine 50'. This second embodiment is different from the first embodiment of FIG. 1 in that the drying device 45 for the pulp band 11 'has a drying passage provided horizontally and having three portions 46, 47 and 48. The first portion 46 is provided for drying by hot air, and the second portion 47 is provided for heating or cooling the “pulp band 11 ′” and for the third cooling.

  The pulp dehydrator according to the first embodiment of FIG. 1 has a processing height of, for example, 2800 mm and a stack height of about 1400 mm and, for example, 150 m / in, for four uses of a width of 4 × 700 mm, a length of 1000 mm, for example. When depositing at a rate of min, it will have a maximum theoretical output of 672000 t / year for continuous operation at 350 working days per year.

  For example, during packaging operation at a speed of 55 m / min and a packaging height of about 500-600 mm, the output is about half of the value mentioned above, which should be taken into account when the cutter is operated open or without overlap. The

  In a deposition operation with a speed of 150 m / min, the payout cycle time is about 3 minutes for each of the four uses. It is thus possible to connect two membrane contractions for stacking packaging to the facility.

  In a packaging operation with a speed of 75 m / min, the delivery cycle time is about 2 minutes. It is therefore completely in frame so that it can connect four wrapping machines, for example based on wire or plastic.

  Switching from the packaging operation to the deposition operation or vice versa can always be performed without a reduction in speed by operating the cutter with interruption. The resulting sheet passes through the discharge gate to the underlying melter, where it is melted along with the strips of pulp strip from the external slitter and returned to the melter.

  Each of the described embodiments can be operated at half power only at the start time, or in the case of temporary coating failure, both internal uses, in a slow coating configuration.

  1 shows a schematic side view of a first embodiment of a pulp dewatering machine according to the present invention.   The schematic side view of 2nd Example of the pulp dehydrator by this invention is shown.

Explanation of symbols

10, 10 'Pulp dewatering machine 20, 20' Net dewatering device 21-24, 25 Circular net device 30, 30 'Press device 40, 45 Drying device 50, 50' Cutting machine

Claims (12)

A pulp dewatering machine comprising a net dewatering device (20, 20 '), a pressing device (30, 30'), a drying device (40, 45) and a cutting machine (50, 50 ') for the pulp band (11). in those with, network dehydrator (20, 20 '), characterized in that the circular network device (21～24,25) has Tsu formed with four suction round net (21 to 24), pulp dewatering Machine. The pulp dewatering machine according to claim 1, characterized in that the circular net device has at least one dandy roll press (26). The pulp dewatering machine according to claim 1 or 2 , characterized in that the pressing device (30, 30 ') has at least one glossy cylinder (31, 32). 4. A pulp dewatering machine according to claim 3 , characterized in that at least one glossy cylinder (31, 32) cooperates with a suction press roll (33, 34). A pulp dewatering machine according to claim 3 or 4 , characterized in that two glossy cylinders (31, 32) are provided for treating both surfaces of the pulp band (11, 11 '). The pulp dewatering machine according to one of claims 3 to 5 , characterized in that the glossy cylinder (31, 32) is provided with a drying cover (35, 36). The pulp dehydrator according to one of claims 1 to 6 , characterized in that the drying device (40) has at least one drying tower (41). After at least one drying tower (41), characterized in that the rocking tower for heating or cooling pulp band (11) (42) and the cooling tower (43) is provided, according to claim 7 Pulp dewatering machine. Drying apparatus (45), characterized in that the pulp zone (11 ') provided horizontally for have drying channel, pulp dewatering machine according to one of claims 1 to 5. The drying device (45) has three parts (46-48), the first part (46) is for drying by hot air, and the second part (47) is for heating or cooling the pulp band (11 '). The pulp dewatering machine according to claim 9 , characterized in that the third part is provided for cooling the pulp band (11 '). Wherein the dancing roller is provided between the end of gloss cylinder and (31, 32) and the drying device (40, 45), pulp dewatering machine according to one of claims 4-10. One of the preceding claims , characterized in that it has a measuring and indicating device for the residual humidity and temperature of the pulp strip (11, 11 ') at least before entering the cutting machine (50, 50'). The pulp dehydrator described in 1 .

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