DE102005017794A1 - Roller for a paper/cardboard production/finishing machine, for water extraction or as a web guide roller, has elongated passage openings in the roller mantle for suction/blowing air flows - Google Patents

Abstract

The roller (1) for a web (8) production/finishing machine, of paper or cardboard, has a rotating mantle (2) with a number of passage openings (3) for suction or blowing air flows from a chamber (7) linked to an underpressure/overpressure supply (6). The passage openings are elongated holes, aligned generally along the direction (L) of web travel.

Description

The The invention relates to a roll of a machine for the production and / or Finishing a running paper, board or other fibrous web, comprising a rotatable roll shell with a plurality of Through openings for suction or for blowing air, the passage openings with at least one connectable to a vacuum or a pressure source chamber keep in touch.

With Vacuum applied suction rolls have long been known. she are used for dewatering the still moist fibrous web, the web guide, the decrease of one Zone of the fibrous web making machine into the next zone (e.g. from the wire section to the dryer section) or to create Fixed points regarding the web draw (e.g., in the dryer section).

Around the effect of the suction zone on a belt or on the belt still moist fibrous web in the former, in the press or dryer section to make the machine even, So far, one has been as possible uniform arrangement of preferably many passages sought. This was done in such a way that a large number of circular Holes in circumferential rows and axial rows in the roll shell with the help of the machining, which is very time consuming and expensive, were introduced. These holes protrude radially into the Inside of the suction roll and are sometimes provided with chamfers or heels, around the vacuumed surface to enlarge.

On DE-U1 29507596 is referred to in this context.

Also Reference is made to DE-A1 10322519. In this document is a web guide device for contactless web guide described. The here proposed guide consists of breathable Material which can be acted upon by compressed air.

Of the Invention is based on the object, a roller for a machine for producing and / or refining a running paper, board or other fibrous web, whose roll jacket including its Through openings cost-effective than previously produced. In this case, the passages be introduced into the roll shell that when operating the Roller ensures full function and one about it Continuous fibrous web, especially paper or board web gently guided will, without it being undesirable fire on the train comes.

According to the invention Task with the creation of a preferably as a suction roll, but also as a blow roll or web guide element operable roller according to claims 1 to 20 and a method for producing a roll shell with corresponding Through openings according to claims 21 until 26 solved.

According to claim 1 shows the roller according to the invention or the roll shell through openings, which in the form of slots or oblong molded perforations are made. They are in their longitudinal direction nearly in the direction of the fibrous web, so approximately in the circumferential direction of Roller or in other words: approximately orthogonal to the roll longitudinal axis, aligned. As a result, especially the web run better supported. Furthermore do not create unwanted footprints on the still moist or wet by coating again Train, what the quality the produced fibrous web increased overall.

A expedient embodiment of Invention is that the passages or the slots oval or in the form of longitudinal slots formed with parallel longitudinal walls are.

By This shape is advantageous because at the same cross-sectional area (compared to previous circular openings) a smaller free length the track unsupported and thus the track can run better supported.

Especially is advantageous if the passages by means of a known thermal ablation method, such as flame cutting, plasma cutting or laser cutting, instead of machining are. This type of production is significantly less expensive than the machining,

By limited burnout the opening geometry no longer just on circular holes, but it is any Shape cost-effective and easy to produce. These arbitrarily producible opening geometries open in the end, more opportunities above all, the intended suction or blowing action across the width of the web to influence specifically.

favors however, as already described, long holes, i. elongated shaped Breakthroughs due to their surprisingly excellent supporting action on the train.

there is on oval shapes as well as on longitudinal slots thought. longitudinal slots however, they are easier to produce than ovals.

At the Making the oval by burnout becomes a revolving motion produced and the burnt-out oval center piece as waste and must be disposed of. On the other hand needs with the slot production only a firing motion in one direction, which is less time consuming is. Furthermore falls burned out Material only as dust and is easier to remove.

Further it is useful if the passages a maximum width of 0.2 to 1 mm, a constant length of 5 to 20 mm and / or in each case a distance from each other of equal / smaller 5-15mm exhibit.

A especially uniform suction is scored when the passages in rows, i. Longitudinal rows, are arranged.

So It can also be done in certain cases be advantageous if the passage openings offset from each other arranged or arranged parallel to each other.

A Another advantageous embodiment is that the longitudinal rows the passages each other at a distance of 3 to 15mm.

It can also be provided that the passages at an angle between 7 ° and 15 ° to the direction of travel the fibrous web are aligned.

Of the elected Angle allows a bridge over the distances between each row. This means that the side and over or mutually arranged openings almost overlapping in the transverse direction, so that the web in the transverse direction completely supplied directly with air and thus can be conducted more gently than before.

A Another embodiment of the invention may be that a made of plastic existing stocking with adequate openings shrunk onto the roll shell. This contributes to the homogenization of Suction / blowing effect and for gentle treatment of the railway.

alternative is also the coating of the roll shell with an air-permeable, porous material possible. This variant was with conventional circular holes excluded because the openings are too large for a continuous Coating were. In the inventive narrow slits or oval holes covers these Coating the passages.

These porous Coating may consist of a single layer or several individual layers or Layers exist.

there Is it possible, that at least one outer layer by means of a thermal spraying process or by sintering on an underlying or only on the lowest layer (carrier layer) can be applied.

The outer layer should be essentially made of the same material as the backing layer consist. This outer layer is preferably made of steel with proportions of chromium, nickel, aluminum and / or molybdenum manufactured. This will be a desired Hardness and wear resistance reached.

A another possibility is that the said outer layer is made up of several homogeneous layers whose air permeability in each case outward decreases.

alternating it is also possible that the outer layer is such that its air resistance to the outside continuously increases.

Besides that is it is possible within the scope of the invention that the air permeability can be targeted in individual areas. This can be done by the air permeability in the peripheral areas and / or in the drain area higher than in other areas is, so that more targeted air can flow through the layers.

Finally will the object of the invention with a method according to claims 21 to 26 solved.

at the method for producing a roll shell of a roll for a machine for producing and / or refining a running paper, board or other fibrous web, is inventively provided that in the roll shell a variety of passages in longitudinal form be introduced. The longitudinal förmen how Ovals or slots with parallel longitudinal sides approximately in Direction of the fibrous web are aligned allow As mentioned in the description of the suction or blower, in surprising Way a better supporting effect for the Train because opposite the previous circular holes with the same cross-sectional area a smaller free length the track unsupported remains.

It is expedient if in the roll shell a plurality of passages with a known per se thermal removal method, such as flame cutting, plasma cutting be introduced or the laser cutting. This is done instead of the previous machining, which saves time and money.

The Production of the roll mantle can be done very expediently, if he initially as a level Plate is made and in this the selected passage openings according to the invention be introduced. Subsequently the plate becomes the desired one cylindrical shape of the roll shell and formed by releasable or unsolvable Compounds, e.g. by welding, together.

This Procedure will be especially applicable if the suction or Blow roller does not rotate during operation or only part of the surface during operation sucked (subjected to negative pressure) or blown (pressurized) becomes.

When Alternative also offers a possibility such that the passage openings according to the invention introduced into an existing cylindrical roller body become. This can be done either in a known 3D-Brennverfahren or under rotation of the roller body while the introduction of the passage openings respectively.

In addition is it is possible after introduction of the passage openings by means of the thermal removal process a surface treatment, for example by means of blasting and / or grinding and / or Perform polishing. Thereby can existing bumps, mainly from thermal abrasion may have been caused be eliminated.

The roll according to the invention let yourself besides the other known uses within a manufacturing machine (for example, a paper machine) particularly advantageous in finishing or Use coating machines. In the latter location, the Roller according to the invention especially advantageous as a suction roll in the leadership of the web and / or suction of unwanted air currents the application unit (see DE-A1- 100 12 257) or else for the suction of the opposite Web page freshly applied coating medium (see DE-A1-101 10 633). In any case, the coater or the application aggregate a fibrous web with a uniform surface (ie without creases, tears, folds, without imprints o.dergl.) To feed to achieve a perfect coating quality.

These quality is achieved with the present invention.

As already executed, The invention also relates to a blow roll, where blowing air from the inside of the roller to the outside is to be delivered, with just produced and arranged through openings.

following the invention will be explained in more detail using an exemplary embodiment.

1 shows in cross section a partial section of the circumference of a roller according to the invention in cross section

2 shows with examples a) to l) the plan view of a roll shell with various arrangements of passage openings according to the invention

3 and 4 : The plan view of preferred arrangements of the passage openings according to the invention in the roll shell

In the 1 is chosen as an example a cylindrical suction roll, because here the invention can be used particularly advantageous and can avoid the feared prints in the fibrous web. In 1 is thus schematically a partial cross section through a driven, cylindrical roller 1 shown. The roller 1 (which in contrast to the suction roll is also operable as a blow roll) consists in the example of a rotatable roll shell 2 , the a plurality of produced by a thermal removal process passages 3 for suction air 4 (when operating the roller 1 as a blower, on the other hand, blown air is discharged to the outside in the opposite direction). The roller 1 or the suction roll comprises a suction zone 5 coming from one with a pressure source 6 (In the case of a suction roll, this is a vacuum source and, in the case of a blow roll, this is an overpressure source) 7 is formed.

About this trained as a suction roll roller 1 runs in the direction L a fibrous web 8th ,

The passages 3 make a connection between the chamber 7 and the exterior of the roller 1 for the purpose of forming the suction zone 5 , To form a uniform and also selectively influenced strength of the suction effect (when operated as a blower roll to form an air cushion or a thin film of air) on the fibrous web 8th (or on non-illustrated press felts or screens to support a still unfinished unfinished fiber web), the passages are made in the form of slots.

In 1 is also still the possibility of attaching a coating of the roller 1 , more precisely the outer surface 2a of the roll mantle 2 with an air-permeable, porous material 9 which may be applied in multiple layers by sintering or a thermal spraying process. This layer of the air-permeable material, the narrow passages 3 cover easily. This would not be possible with the production of circular holes by means of thermal removal methods, because this method only allows holes of larger diameters. The production of holes below 1 mm would also be extremely expensive.

In 2 are different ways of arranging the individual passages 3 in the roll jacket 2 shown in plan view.

For reasons of clarity, only a few reference signs have been drawn, since apart from the arrangement of the passage openings 3 the individual elements in all illustrations occur equally.

The passages 3 are, as before, as small circular parallel holes with the same distance from each other (Figure a) or in staggered arrangement and equally equally spaced (Figure b) produced and are therefore the sake of completeness listed here.

In the context of the invention, however, the passage openings 3 proposed in the form of oblong holes. These are in the form of ovals 3.2 or elongated slots 3.1 and are shown as short dashes in figures c) to l). The passages 3 have a maximum width b of 0.2 to 1 mm. The dimensions also apply as the diameter of the circular holes in pictures a) and b).

The constant length d of the preferred elongated and approximately in the direction of L aligned passage openings 3 , as the pictures c) to l) indicate is about 5 to 20 mm.

in the Example c) and d) is the length 5mm, in the rest Examples 10mm.

In addition, the passage openings 3 in each case a distance a to each other between less than 5mm to less than 15mm. In the example according to Figure a) and b) with small circular holes, the distance a) is only 4mm. In Example c) and g) each 10 mm, in Example d) f) h) i) k) and l) each 14mm, in Example j) 6mm.

Figures a) to l) show that the passage openings 3 are arranged in rows R.

In addition, the individual passage openings 3 opposite to a neighboring row, as shown in the pictures d), f), g), i), k), j). In this case, spacings between the individual rows R, as shown in Figure d) and f) or no intermediate distances between the individual rows R, as g), or overlaps the ends of the passages 3 as picture j) shows possible.

The passages 3 can also be arranged in their rows R parallel next to each other and with greater spacing between the rows R, as Figure e) shows.

R rows of passages 3 have each other a distance A of about 3 to 18mm.

Figures k) and l) are intended to show that it is also possible to use the openings 3 at an angle α to the direction L of the fibrous web to align, because thus an increase in the effective area of the suction openings 3 is seen by their coverage in the edge regions in the transverse direction Q, is possible and thereby the fibrous web, not shown here is better performed. The angle α is between 7 ° and 15 °.

Below the figures a) to l), a horizontal arrow L is shown, which is the running direction of the fibrous web 8th should specify.

These passages produced by the thermal removal process 3 or also as long holes markable, are in oval form - see 3 - or as slots with parallel long sides 3a -please refer 4 - produced.

The Production takes place with a thermal removal method, which means Flame cutting, plasma cutting or by means of more precise working Laser cutting takes place.

When making the oval 3.2 by burnout is a circumferential movement (see curved arrow in the 3 ) and the burnt out oval centerpiece M (see crossed hatching) is waste and must be discarded. In contrast, when making slots needs 3.1 in each case only one firing movement, corresponding to the illustrated horizontal arrow, are made in one direction, which is less complicated. In addition, burnt out material only falls as dust and is also easier to remove.

In both 3 and 4 the burnt out material is dotted.

1

roller (Suction or blower roll)

2

roll shell

2a

outer surface

3

Through opening

3.1

slot

3.2

oval

3a

long side

4

suction

5

suction zone

6

pressure source (for companies or overpressure)

7

chamber

8th

Fibrous web

9

porous material

A

row spacing

L

direction

M

centerpiece

Q

transversely

R

line

a

distance

b

width

d

length

α

angle

Claims (26)

Roller ( 1 ) a machine for producing and / or refining a running paper, board or other fibrous web ( 8th ), comprising a rotatable roll shell ( 2 ) with a plurality of passages ( 3 ) for suction or blown air ( 4 ), wherein the passage openings ( 3 ) with at least one to a vacuum or overpressure source ( 6 ) connectable chamber ( 7 ), characterized in that the passage openings ( 3 ) have the shape of elongated holes whose longitudinal directions approximately in the running direction (L) of the fibrous web passing over the roller ( 8th ) are aligned. Roller according to claim 1, characterized in that the passage openings ( 3 ) or the slots either as an oval ( 3.1 ) or in the form of longitudinal slots ( 3.2 ) with parallel longitudinal walls ( 3a ) are formed. Roller according to claim 1 and 2, characterized in that the passage openings ( 3 ) are produced by means of a known per se thermal removal method, such as flame cutting, plasma cutting or laser cutting, instead of a machining. Roller according to claim 1 to 3, characterized in that the passage openings ( 3 ) have a maximum width (b) of 0.2 to 1 mm. Roller according to claim 1 to 4, characterized in that the passage openings ( 3 ) have a constant length (d) of 5 to 20 mm. Roller according to claim 1 to 5, characterized in that the passage openings ( 3 ) each have a distance (a) from each other of = <5-15mm. Roller according to claim 1 to 6, characterized in that the passage openings ( 3 ) are arranged in rows (R). Roller according to claim 7, characterized in that the passage openings ( 3 ) are offset from one another. Roller according to claim 7, characterized in that the passage openings ( 3 ) are arranged parallel to each other. Roller according to claim 7, characterized in that the rows of passages ( 3 ) to each other at a distance (A) of 3 to 15mm. Roller according to one of claims 7 to 10, characterized in that the passage openings ( 3 ) are aligned at an angle between 7 ° and 15 ° to the running direction (L). Roller according to one or more of the preceding claims, characterized in that a sieve stock made of plastic with adequate passage openings ( 3 ) on the roll shell ( 2 ) has shrunk. Roll according to one or more of the preceding claims, characterized in that the roll shell ( 2 ) with an air-permeable, porous material ( 9 ), which slits the slotted ( 3.2 ) or oval openings ( 3.1 ) and the porous material ( 9 ) forms the outermost layer. Roller according to claim 13, characterized in that the porous material ( 9 ) can be applied in at least one layer. Roll according to one or more of the preceding claims, characterized in that the roll shell ( 2 ) consists of a carrier layer and at least one outer layer. Roller according to Claim 15, characterized that the at least one outer layer by means of a thermal spraying process or by sintering on the made of steel or a fiber composite material, such as GRP or CFK, existing carrier layer can be applied. Roller according to claim 16, characterized gekenn characterized in that the outer layer is preferably made of steel with proportions of chromium, nickel, aluminum and / or molybdenum. Roller according to one or more of claims 14 to 17, characterized in that the outer layer of a plurality of homogeneous Layers is constructed, whose air permeability in each case to the outside decreases. Roller according to one or more of claims 14 to 18, characterized in that the outer layer is constructed that their air resistance increases continuously to the outside. Roll according to one or more of claims 14 to 19, characterized in that the air permeability in individual regions of the roll ( 1 ) is specifically beinflussbar, such that in their edge regions and / or in the discharge region of the fibrous web ( 8th ) the air permeability is higher than in other areas. Process for producing a roll shell ( 2 ) of a usable as a suction or blow roll roller ( 1 ) for a machine for producing and / or finishing a moving paper, board or other fibrous web ( 8th ), characterized in that the passage openings ( 3 ) in elongated form in the roll shell ( 2 ) are introduced with a longitudinal extension of the passage openings ( 3 ) approximately in the running direction (L) of the roller ( 1 ) running fibrous web ( 8th ). A method according to claim 21, characterized in that in the roll shell ( 2 ) a plurality of passages ( 3 ), be introduced instead of a previous machining, with a known per se thermal removal method, such as flame cutting, plasma cutting or laser cutting. A method according to claim 21 and 22, characterized in that the roll shell ( 2 ) is first made as a flat plate and in this the selected passages ( 3 ), then a deformation of the flat plate to a desired cylindrical shape of the roll shell ( 2 ), wherein the formed plate by releasable or non-detachable compounds, such as welding process, to a closed cylindrical roll shell ( 2 ) is joined together. A method according to claim 21 and 22, characterized in that the passage openings ( 3 ) in an existing cylindrical roll shell ( 2 ) are introduced either by means of known 3D-burning process or by rotation of the roll shell ( 2 ) during the introduction of the passage openings ( 3 ). Method according to one of claims 21 to 24, characterized in that after introduction of the passage openings ( 3 ) by means of the thermal removal method, a surface treatment, for example by means of blasting method, such as sandblasting, and / or grinding and / or polishing is performed. Method according to one or more of claims 21 to 25, characterized in that the created roll shell ( 2 ) with an outer, air-permeable layer of porous material ( 9 ) and this layer is applied by a thermal spraying method or by sintering.