JP2010018381A - Roll for paper making machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a roll for a paper making machine capable of coping with width widening and high speed without generating wrinkles and is excellent in ease of operation as well as safety and maintenance. <P>SOLUTION: The roll is a roll of a winder or the like, including: a roll cell mainly formed from carbon fiber reinforced plastics (CFRP); a metal sleeve with an air relief groove, fitted to the roll cell outside; and a thermal-spraying coating of carbide-based thermet coated on an outer-peripheral surface of the metal sleeve. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a roll for a papermaking machine and a roll for a film production machine, and particularly to a roll suitably used as a roll for winding paper (web) conveyed at high speed without causing wrinkles due to air entrainment.

In recent years, widening and high speed have become mainstream for the purpose of improving productivity of papermaking machines.
That is, with an increase in the speed of the papermaking process, a roll (winder roll) used in a winder or the like tends to be wider and faster. As a result, the paper wound in the winding process usually generates wrinkles to some extent, and it is indispensable to perform a wrinkling process before being cut into a predetermined paper width size and wound. .

  However, even if the paper removal process is performed at high speed, new paper is often generated, and development of a papermaking machine that does not cause such a problem is demanded. In this regard, to prevent wrinkles, it is important how to smoothly remove the air trapped between the paper and the roll. In general, manufacturers have adopted grooved rolls to deal with this. Yes. Further, as the speed increases, higher strength rolls are also required. Among them, in particular, the guide roll before and after the slitter in the winder that divides the web as shown in FIG. 1 needs to have a small moment of inertia for use as a non-driving roll, and the roll diameter must be reduced. Since it cannot be obtained, many metal multi-divided rolls as shown in FIG. 2 are employed.

  Here, FIG. 1 is a diagram showing a roll configuration in the winding process, and reference numeral 1 in the drawing is a wound paper (raw fabric roll or the like), and a wide paper 2 made by a paper machine (not shown) is wound up. Is. 3 is a guide roll, 4 is a guide roll before and after the slitter targeted by the present invention, 5 and 6 are a plurality of sets of slitters, 7 is a drum roll, and 8 is a small roll of paper wound in a divided manner.

  FIG. 2 is an enlarged view showing a multi-division type of the guide roll before and after the slitter described above, in which 9 is a roll cell, 10 is a bearing for connecting the divided roll cells, and 11 is a segment of the divided roll cell. It is the bracket used in order to support individually.

  FIG. 3 shows a part of the surface shape pattern of the guide roll 4 before and after the slitter. In FIG. 3, reference numeral 12 in the drawing removes air caught between the roll and the paper 2 by high-speed rotation. It is an air escape groove carved in the spiral for. The details of the groove A are shown in an enlarged manner in FIG. This air escape groove shape 13 is designed not only as shown in the figure but also various types according to the operating conditions.

The conventional guide roll 4 before and after the slitter as shown in FIG. 2 is generally a metal roll that does not have a driving device, for example, an aluminum roll. However, in order to compensate for the required strength during high-speed rotation, a short metal roll is used. Multiple rolls made by connecting multiple rolls via a built-in bearing 10 to form a single roll. Dangerous rotation due to high-speed rotation by reducing the amount of flexure, vibration, and dynamic balance of the roll. (Patent Document 1).
Japanese Patent Laid-Open No. 2004-189412

  However, since the multi-division roll described in Patent Document 1 is composed of a large number of segments, it is inevitably inferior to a roll composed of a single cell in terms of operability, safety and maintainability. Met. In order to solve such a problem, a method of reducing the number of divisions by enlarging the roll diameter and increasing the elastic modulus (by reducing the amount of bending) can be considered. However, such a method increases the moment of inertia of the roll, and the non-driven type has a problem that the roll cannot follow the speed of the paper especially at the start and stop.

The object of the present invention is to reduce the number of divisions of the multi-division roll as much as possible without causing paper wrinkles even at high speed operation, and it is excellent in operability and safety and maintainability (maintenance). It is to propose a roll for a papermaking machine.
In order to achieve this object, the present invention uses a roll cell material that is lightweight and has a high elastic modulus to solve the problem of moment of inertia and the problem of high speed rotation due to bending, and to prevent wrinkles. It was decided to produce a roll with improved air gripping properties (paper does not slip easily on the roll surface) and roll wear resistance while providing air vent grooves on the surface.

In this regard, the inventors have further studied. As a result, it is possible to effectively utilize the space of the winder that divides the current web, and to use a roll for a small number division type paper machine that can cope with widening and high speed of the paper with a small diameter that is not driven, i.e., a decimal division type. We have succeeded in developing a winder roll with excellent operability, for example, a guide roll placed before and after the winder slitter.
The “papermaking” of the roll for papermaking machine in the present invention is used as a phrase that includes not only the production of paper made of cellulose pulp but also the production of synthetic paper and film.

  That is, the present invention comprises at least a roll cell made of a carbon fiber composite material and a metal sleeve fitted to the outside of the roll cell, an air escape groove is formed on the outer peripheral surface of the metal sleeve, and a sprayed coating is further formed thereon. It is a roll for a papermaking machine formed with a coating.

  In the present invention, the carbon fiber composite material preferably has a Young's modulus of 220 GPa or more, and the sprayed coating is more preferably formed by spraying a carbide cermet, a boride cermet, an oxide cermet or the like.

  More preferably, the roll of the present invention is used as a non-driving roll, disposed in a winder, or made up of a two-divided minority division type roll or a single-type roll without division.

The roll for a papermaking machine according to the present invention configured as described above can be expected to have the following effects.
(1) By using a carbon fiber composite material in the roll cell, the moment of inertia is reduced by reducing the weight, and the critical speed associated with high-speed rotation is avoided by suppressing the flexure by improving the Young's modulus (elastic coefficient). Made it easier to do. Thereby, the division | segmentation number of a multi-division type | mold roll can be made small, without providing a special drive device. If possible, it is preferable to use a single roll without division.
(2) The generation of wrinkles can be prevented by fitting a metal sleeve to the outside of the roll cell and performing air venting groove processing.
(3) Since a spray coating (carbide cermet, etc.) is provided on the roll surface, it is possible to improve paper passing properties, gripping properties, wear resistance, prevent operational troubles, and improve roll life. It becomes like this.
(4) It can be adapted to existing winders well.

  FIG. 5 shows an example applied to a guide roll before and after a slitter of a winder that divides a web in a width direction as an example of a winder roll for a papermaking machine having a configuration suitable for the present invention. The guide roll 4 before and after the slitter is a two-piece small-divided roll, and the roll body (core part), that is, the roll cell 14 is made of a carbon fiber composite material (CFRP) which is a highly elastic material. It is.

  A metal sleeve 15 formed by forming a spiral or concentric air escape groove on the outer peripheral surface is fitted on the outside of the roll cell 14 by external fitting. The metal sleeve 15 is preferably made of stainless steel or aluminum, but the material is not particularly limited.

  On the outer peripheral surface of the metal sleeve 15 subjected to the groove processing, a thermal spray coating formed by spraying a hard thermal spray material for the purpose of improving the gripping property with the paper and suppressing the abrasion due to the sliding of the paper. 16 is coated.

  Here, the code | symbol 17 in FIG. 6 is a bearing attached to the roll axial part, 18 is a bracket which supports the center part of a 2 division | segmentation roll. FIGS. 7 and 8 are enlarged views of part B of FIG. 6, and are enlarged sectional views showing a state in which the metal sleeve 15 is fitted on the outer side of the roll cell 14 and the thermal spray coating 16 is formed on the outer peripheral surface of the metal sleeve. Show. In addition, as shown in FIG. 8, the shape of the groove may be one in which two spiral grooves are processed from the center of the roll toward both ends.

  By the way, in the present invention, the carbon fiber composite material (CFRP) used as a roll core material (roll cell) is preferably molded with high elastic pitch-based carbon fiber, and the Young's modulus after molding is preferably 220 GPa or more, and Preferably it is 240 GPa or more. Moreover, an upper limit is normally 550 GPa or less from the surface of cost, Preferably it is 500 GPa or less. This is a highly elastic material showing a considerably high Young's modulus as compared with steel rolls having a Young's modulus of about 210 GPa or aluminum: about 7 GPa. This means that the roll diameter can be made smaller and the cell thickness can be made thinner when compared with a steel roll, considering the roll deflection during winder operation. Furthermore, when a roll cell made of carbon fiber composite material is used, it is only necessary to connect one or usually three or less rolls, and a smaller number of rolls may be connected as compared with a conventional metal roll cell.

For example, when the length of the roll body is 3,510 mm and the thickness of the cell is 10.5 mm, the total deflection during operation is 0.188 mm in the case of a steel roll, whereas the CFRP roll is When it is a roll core, it is as small as 0.057 mm. In addition, when comparing the moment of inertia between a roll having a CFRP core and a steel roll, the moment of inertia of the steel roll is 6.51 kg · m ^2, while that of a roll made of CFRP is 1.84 kg · m ^2. And small. This means that starting and stopping are instantaneous, and when used as a non-driving roll, the CFRP roll according to the present invention has little relative slippage with the paper even with slight contact with the paper, and the paper speed is instantaneous. It means that it can follow.

  The roll of the present invention preferably has a single roll length of 1600 to 4000 mm, a post-connection length of 3200 to 12000 mm, a roll diameter of 120 to 330 mm, a cell thickness of 5.0 to 25 mm, and a single roll length. A roll made of carbon fiber composite material having a diameter to diameter ratio (L / D) of 12 to 20 is used. For this reason, it is possible to provide a roll having a small amount of deflection and a small moment of inertia as compared with that of a steel roll.

  Furthermore, the major difference between the steel roll and the CFRP roll core is that the steel roll has a resonance point in the vicinity of about ½ of the dangerous rotational speed, and operation near the resonance point cannot be performed. However, in the case of a roll using CFRP as a core material, the vibration at this 1/2 resonance point is small, and after passing this resonance point, it is very stable up to the vicinity of the dangerous rotation speed, so that operation by high-speed rotation is possible. Is meant to be.

  In addition, when a roll using CFRP as a core material is used according to the present invention, the roll body can be reduced in weight and at the same time, and a small high-performance bearing can be adopted as a bearing. Operation becomes possible.

  Further, in the present invention, the reason why the metal sleeve 15 is externally fitted to the outside of the roll cell 14 made of carbon fiber composite material is that it is difficult to process the air escape groove 12 directly on the surface of the roll cell 14 made of CFRP. It was adopted to enable processing. As a method for inserting and fitting the metal sleeve 15 to the outside of the roll cell 14, a general press-fitting method is preferable. However, the metal sleeve 15 may be fitted by a process such as hot fitting or cold fitting, and is not particularly limited. .

An air escape groove is formed on the outer peripheral surface of the metal sleeve. The air escape groove has a value S / L [mm] obtained by dividing the total cross-sectional area S [mm ² ] of the groove by the roll surface length L [mm] in a straight line in the surface length direction on the surface in contact with the paper. Is equivalent to 20 times or less of the air layer thickness H calculated by the following formula, preferably 2 times or more and 10 times or less, more preferably 2 times or more and 5 times or less of H. It is preferable to make it. If the S / L is smaller than H, air is not easily escaped efficiently. Also, if the groove shape is designed so that S / L exceeds 20 times that of H, the grooves are inevitably wide, deep and narrow, which may cause damage to the web transported on the roll. Absent.

  In this way, by fitting a metal sleeve having an air escape groove on the outer peripheral surface to a roll cell made of carbon fiber composite material, the amount of flexure of the roll is reduced, and furthermore, the generation of wrinkles is made easier to escape air. It becomes easy to suppress.

  The air escape groove has, for example, a semicircular shape having a groove width of 3.0 mm, a groove depth of 0.8 mm, and a groove pitch of 10 mm.

  The reason why the desired material is sprayed on the outer peripheral surface of the metal sleeve 15 is that the roll proposed in the present invention generally conveys the paper to be passed at a very high speed. This is because it was necessary to cope with this. As an example of the thermal spray coating, it is desirable that the surface has relatively fine irregularities, is hard, and has wear resistance. For this purpose, high-speed flame spraying of carbide-based cermets, boride-based cermets, oxide-based cermets or the like is desirable, but plasma spraying may also be used.

Example 1
This embodiment is an example in which a wide paper wound by a paper machine is applied to a guide roll before and after a slitter for a winder that divides a wound paper for processing as a product in the final stage. A test roll simulating a roll was manufactured and its processability and quality were verified.

  FIG. 9 shows the shape of a test roll produced for the example. This roll uses a carbon fiber composite material having a Young's modulus of 240 GPa, the length of the roll cell is 400 mm, and 50 mmφ shafts are provided at both ends of the roll cell. The structure of this roll is such that a stainless steel (SUS304) sleeve 15 is fitted to the outside of the CFRP roll cell 14, and the surface is further grooved as shown in detail in part A of FIG. It is something that is given. Further, the surface of this roll has a three-layer structure in which tungsten carbide cermet is spray-coated by high-speed flame spraying. 10 shows the appearance after spraying, FIG. 11 shows the result of observation of the groove shape before spraying by resin molding, and FIG. 12 shows a photograph of the result of observation of the groove shape after spraying by resin molding. Show. According to these results, it was confirmed that the groove shape hardly changed before and after thermal spraying.

  Further, a bearing was attached to the shaft portion of the test roll, and an evaluation test was performed on roll performance by high-speed rotation on a balance machine. The test is performed at a maximum speed of 5,000 rpm by gradually increasing the rotational speed. According to the measurement result of the dynamic balance and the dynamic shake at this time, the unbalance amount in the dynamic balance was about 1 g, and the maximum dynamic shake was 0.05 mm.

(Example 2)
Based on the result in Example 1, a roll suitable for the present invention was manufactured, and the performance was verified with a general-purpose winder that divides the web in the width direction. The roll structure was the same as that shown in FIG. 5, and a two-part roll structure in which two rolls were connected by a bearing at the center. The shape of one of the divided single rolls is 165 mmφ × 2700 mm, a stainless steel (SUS304) sleeve is fitted on the outside of the CFRP roll cell, groove processing is performed, and WC cermet is further sprayed on the surface of the WC cermet. By this method, a sprayed coating having a thickness of about 50 μm was formed.

  A performance test was conducted on each single roll produced in this manner. As an evaluation method, these single rolls were set on a balance machine and rotated at a maximum of 4800 rpm (about 2500 m / min) by gradually increasing the rotation while adjusting the balance. The amount of dynamic imbalance at this time was about 0.7 g, and the maximum runout was 0.04 mm. Moreover, the rotation in a very stable state without vibration was maintained.

  Next, another single roll manufactured in the same manner as the above roll was tested. As shown in FIG. 5, the two single rolls were connected by a central built-in bearing, and a single roll was formed by three-point support (bracket). Then, after fixing a bracket on a surface plate and performing centering, the performance by high-speed rotation of this connection type roll was evaluated. As a result, it was confirmed that the two splicing rolls can obtain the same rotational performance as that of the single roll. Furthermore, it was confirmed that stable operation was possible without the occurrence of roll vibration, paper floating and wrinkles within the operating condition range from the stopped state to 4800 rpm.

  The roll for papermaking machines according to the present invention can be suitably used as a roll for a winder that divides a web. It can also be used in rewinding winders, flat cutters, coating machines, paper machines and the like. Similarly, it can be used as a roll for a winder that divides a film take-up roll, and can also be used in a winder for film rewind, a flat cutter, and a molding machine.

The basic diagram which shows the structure of a winder. Sectional drawing which shows the structural example of a metal multi-partition type | mold roll. The front view of the metal multi-division type | mold roll which formed the air vent groove. The partial view of the roll explaining the shape of an air vent groove. Sectional drawing which shows the structural example of the roll which concerns on this invention. The front view which shows the detail of the air vent groove shape of the roll which concerns on this invention. The fragmentary figure which shows the cross-section of the roll which concerns on this invention. The fragmentary figure which shows the detail of the air vent groove shape of the roll which concerns on this invention. Sectional drawing which shows the shape of the test roll which concerns on this invention, and its fragmentary figure. The photograph which shows the external appearance of the test roll which concerns on this invention. The enlarged photograph of the groove shape before thermal spraying of this invention test roll. The enlarged photograph of the groove shape after thermal spraying of this invention test roll.

Explanation of symbols

1 Wrapping paper (raw roll)
2 Wide paper 3 Guide roll 4 Slitter The guide roll 5 Slitter 6 Slitter 7 Drum roll 8 Small roll paper 9 Roll cell 10 Bearing 11 Bracket 12 Air escape groove 13 Air escape groove 14 Carbon fiber composite roll cell 15 Metal sleeve 16 Thermal spray coating 17 Bearing 18 Bracket

Claims (6)

A papermaking machine comprising at least a roll cell made of a carbon fiber composite material and a metal sleeve fitted to the outside of the roll cell, wherein an air escape groove is formed on the outer peripheral surface of the metal sleeve, and a thermal spray coating is formed thereon. Machine roll. The papermaking machine roll according to claim 1 or 2, wherein the carbon fiber composite material has a Young's modulus of 220 GPa or more. The roll for papermaking machine according to claim 1 or 2, wherein the sprayed coating is formed by spraying a carbide cermet. The roll for papermaking machines according to any one of claims 1 to 3, wherein the roll is used as a non-driving roll. The roll for a papermaking machine according to any one of claims 1 to 4, wherein the roll is disposed in a winder. The roll for papermaking machine according to any one of claims 1 to 5, wherein the roll is a split type roll.

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