SU1291642A2 - Suction box of wire unit of paper-making machine - Google Patents

Abstract

The invention relates to a mesh part of a paper machine and can be used in the paper and paper industry. The purpose of the additional invention is to improve the quality of the molded web by adjusting the dispersing effect on the mass to be dehydrated on the net. The suction box holder is formed by alternating dehydrating strips and strips 3 for scouring the pulp. Grooves 5 are made on the bars 3. Between the grooves, the bushings 7 are mounted. When the axis 10 is moved, the Cams 9 raise or lower the pushers 6, which, acting on the liners 7 j, cause a change in the height of the corrugations 5. 1 hp, f-le, 5 silt . $ (P to from 05 4 :: ь to vvvwv Figure 3 N)

Description

I

The invention relates to the paper part of a paper machine, can be used in the pulp and paper industry and is an improvement on the device according to the basic author. St. No. 1139784,

The purpose of the invention is to improve the quality of the molded web by adjusting the dispersing effect on the mass to be dewatered on the net.

FIG. 1 shows a suction box, a cross-section; on the flg. 2 - the same, top view; in fig. 3 shows section A-A in FIG. 2; on .fig. 4 shows a pusher bar joint assembly; in fig. 5 is a diagram of connecting axes with pushers in groups.

The suction box contains a body 1 and, formed by alternating dewatering bars 2 and bars 3 for p, the paper pulp. The ribs 4 support the bars 2 and 3. On the bars 3 there are rectangular semi-circular cross-sections (fig. 5), inclined oi to the direction of movement of the grid.

The corrugations 5 on the bars 3 are made in different directions. Pushers 6 are connected to bars 3 by means of movable inserts 7. Pushers 6 are connected by a hinged connection 8 with eccentrically fixed cams 9 on axis 10, are located along plate 3 and are connected to a drive of rotational motion.

In addition, the axles 10 are connected to the pushers 6 in groups (by zones of regulation). The adjustment zone is formed by connecting one axis 10 with a part of the pushers 6 of the bar 3. The number of pushers constituting one group, as well as the number of groups, depends on the width of the grid of the paper machine. The optimum dimensions of the corrugations 5 depend on the operating modes of the machine and the type of product produced.

Suction box net part works as follows.

When the box operates in the housing 1, a vacuum is created, under the action of which the web is dewatered on the grid moving along the crest of the box. Water from the mass layer passes through the screen and is discharged through the gaps between the bars 2 and 3 in the housing 1, and then is removed from the box.

ten

During the dehydration of the web at the first steps of the net of the strip 2, the flow of water filtered through the net enters their front faces and is diverted into the casing 1 of the box. In this case, the layer of water under the screen is also removed by the sharp edges of the strip 2 and is directed to the housing 1. When the web is dehydrated, the first layers of the drawer 2 form a layer of settled fibers on the net and the filtration resistance of the water from the mass above this layer increases. A layer of filtered water, 5 hanging under the screen, the passage between the screens and the strips 3, interacts with the surface of the corrugations 5, is divided into separate streams, which change the direction of their movement due to the arrangement of the angles ci to the direction of the movement of the grid. As a result, a component of the velocity of these flows appears, directed across the movement of the mesh, the value of which depends on the geometrical parameters of the corrugations, the speed of the papermaking machine, the type and concentration of the paper pulp.

Thus, between the corrugations in the layer of filtered water, a multitude of swirling streams containing turbulent eddies are organized. Spinning streams throw parts of the filtered subgrid water layer through the mesh into the molded web, thereby destroying the layer of settled fibers, dispersing the pulp flow moving on the mesh, disorienting the pulp fiber along the direction of movement of the mesh. This results in a more uniform distribution of the fibers in the cast sheet and an intensification of the dewatering process.

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When the axis 10 rotates, for example, using the handwheel, the eccentrically fixed cams 9, rotating with the axis 10, raise or lower, depending on the direction of rotation of the axis 10, due to the hinge 8, the pushers 6, which act upon the inserts 7 of the bars 3, cause the change in the height of the corrugations 5, which leads to a change in the degree of turbulence in the vortex flows between the grid and the corrugations 5, contributes to the improvement of the quality of the cast sheet during

switching to another type of product and changing the speed of the car.

In addition, when one of the axes 10 rotates, the height of the corrugations 5 of that zone of the bar 3, where the pushers 6 are connected to the cams 9 of the rotatable axis 10, is adjusted, which results in an adjustment of the dispersing effect on the pulp flow along the net width, eliminating the appearance of jetting. All this contributes to a more uniform distribution of fibers in the structure of the sheet being cast, and to improving the quality of the paper web.

The use of the invention will significantly improve the quality of the cast sheet by adjusting the dispersing effect on the flux of paper pulp, disorienting the fibers in the flux of paper pulp, more uniform distribution of the fibers across the width of the maximum mesh, which will allow you to 5 ° 5

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to start up products with a mass of 1 m.

Claims (2)

1. The suction shch11k of the grid part of the paper machine according to the ed. St. No. 1139784, characterized in that, in order to improve the quality of the web formed by adjusting the dispersing effect on the mass to be dried on the net, the strips for scouring the fibrous mass have inserts between the corrugations mounted with the means for moving them along the height of the corresponding corrugations. 2. The box according to claim 1, characterized in that the means for moving the liners are designed as eccentrically mounted on the axis of the cams interacting with the pushers fixed in the inserts of the corresponding grooves. 2 j 1 J 5 7 -one ; F 70 FIG. 2 cpits. MM: f f f f at f.Kr W W Compiled by Yu.Kp pin Editor I.Nikolaychuk Tehred I.Popovich Corrector A.Ilyin 208/31 Circulation 341 Subscription VNISh State Committee of the USSR for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., d, 4/5 Production and printing company, Uzhgorod, st. Project, 4 (c / ff.S 9 ff