JPS597820B2 - Method for producing fiber sheet material and equipment for its implementation - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to fiber processing, and more particularly to a method for producing fibrous sheet materials and an apparatus for carrying out the method.

The invention can be most advantageously used in the valve and paper, textile and construction material industries for the production of various papers, boards, non-woven fabrics, felts, construction boards.

In order to produce fiber sheet materials, it is important to obtain a uniform distribution of fiber material in the gas stream and to maintain the initial dispersion value of the gas fiber stream along the entire path of the flow.

The gas fiber stream must have special flow properties that allow the stream shape to be deformed into a flat one and the internal structure of the gas fiber stream to be deformed to obtain a homogeneous fiber distribution throughout the flow.

The dispersion value of the gas fiber flow is considered to be the ratio of the capacity of individual fibers, ie, groups of small fibers, to the capacity of individual fibers of the modal length, ie, the length that predominates in the fiber length distribution. A homogeneous fiber distribution in a gas stream is defined as a fiber concentration in each individual stream with little or no variation (ConcentratiOn).
It is considered that The dispersion value of the gas fiber flow and the homogeneous fiber distribution throughout the flow determine the uniformity of the structural homogeneity of the resulting fiber sheet material, and the degree of fiber concentration in the gas flow determines the degree of fiber concentration on a flat screen. Determining the volume of gas to be removed from the gas fiber mixture to form a layer of fiber material. On the other hand, the dispersion value of the gaseous fiber suspension is reduced due to the high self-adhesion of the fibers, ie groups of separated fibers result.

The fiber concentration must be low to reduce the possibility of fiber collisions causing adhesion and swarming due to disturbance forces introduced in the moving gas fiber stream. Generally, the fiber concentration is between 5 and 30 V/Rr, depending on the nature of the material to be produced and the type of fiber. is within the range of Moreover, the high fiber concentration of the gas fiber stream reduces the fluidity of the stream, and this fluidity is due to the deformation of the gas fiber stream's profile, e.g. from a circular to a flat shape, and due to the cross-sectional is a necessary condition for the variation of the internal structure of the gas fiber flow to obtain a uniform distribution of the velocity range (Feld) in It is.

Therefore, a low fiber concentration of gaseous fibers is a prerequisite for forming fibrous sheet materials.

Therefore, the layers of fibrous material can be applied at high speeds, e.g.
When formed on a flat screen moving in the speed range of 00 m/min, a significant amount of gas is removed from the gas fiber mixture. A flat screen deposited with fibers to form a layer of fibrous material has a high resistance coefficient of 20 to 500, depending on the fiber type and the thickness of the fiber layer.

Therefore, the removal of large amounts of gas per unit time required for high-speed production of fiber layers results in increased power consumption.
The power expended to overcome resistance can be reduced with a suitable increase in the active area of the flat screen.

However, this results in an undesirable increase in the size of the equipment,
As a result, the amount of input metal material increases. On the other hand, when gas is removed through the screen and the fiber layer deposited on it, the power expended to overcome the resistance developed on the screen during the layering process depends on the concentration of fibers in the gas fiber stream. can be decreased by increasing

In this case, the gas fiber flow is expanded before being fed onto the screen to obtain a uniform distribution of velocity range, a homogeneous distribution of fibers over the total flow volume and an increase in the dispersion value of the gas fiber flow. It must be. All of these are
It is possible to obtain a fibrous material of homogeneous structure, ie a layer of uniform material with mechanical and physical characteristics. Methods for producing fibrous sheet materials are known in the art (see US Pat. No. 2,689,985).

According to this method, the fiber material is finely divided and fed into an expanding gas stream where it is deformed by mechanical mixing, whereby a uniform distribution of the velocity range is achieved and a small Partition of the large mass into fibrous solids occurs. The gas fiber mixture is then deposited onto the screen to form a fiber layer thereon. The apparatus for carrying out this method for the production of fibrous sheet material consists of a disc mill for the individual separation of the fibers, which mill is connected via a discharge pipe to a diffuser having widening side walls and a front wall. , at which a rotating roller with teeth is arranged.

The gaseous fiber stream is transformed by mechanical agitation caused by rotating rollers, resulting in a homogeneous fiber distribution over the entire volume of the gaseous fiber stream. A gas fiber stream is fed from a diffuser onto a flat screen. A suction box is supported below the screen for removing gas from the gas fiber stream fed onto the screen during the layering process.

A disadvantage of the above method and the apparatus for carrying it out is that the gaseous fiber stream with a fiber concentration as low as 5 to 10 y/y is deformed due to localized fiber flocculation caused by mechanical agitation. It is possible.

When a high concentration gas fiber stream is used, homogeneous distribution of the fibers over the entire volume of the stream is prevented. Moreover, the gaseous fiber stream fed onto a flat screen has a low fiber concentration.

This is due to the power consumption spent to overcome the resistance developed on the flat screen during the fibrous layer formation process, when large amounts of gas are removed through the screen and the fibrous layer deposited on it. will increase. A gaseous fiber stream with a high fiber concentration can be fed onto a screen if a modification of the stream is obtained with a polydispersity of the fibers in the gas stream before being fed onto a flat screen.
Methods for producing fibrous sheet materials are known in the art.

In this method, fibrous material is crushed and fed into an expanding gas stream. The resulting gaseous fiber stream is subjected to polydispersion and then fed onto a flat screen to form a fiber layer thereon. The apparatus for carrying out this method consists of a diffuser having flared side walls, the inlet opening of which communicates with a conduit for supplying a flow of gaseous fibers;
The outlet opening is connected to a rectangular upright chamber.

Several flat airfoil-shaped bodies are arranged in the chamber, their faces parallel to the side walls of the chamber, and the upper part of each body is arranged inside the diffuser. When the gas fiber stream impinges on the flat airfoil body, a polydispersion effect occurs due to the elastic repulsion of the fibers against the convex surface of the flat airfoil body, which causes the gas fiber stream to form a rectangular shape. It is evenly distributed over the chamber along the edges, resulting in a uniform distribution of velocity ranges.

However, the above-described fibrous sheet material productivity methods and equipment for implementing the same have failed to transform gaseous fiber streams having fiber concentrations higher than 5 to 15 y/y.

If a gas fiber stream with a high fiber concentration is supplied to a flat shaped body, the force in the distribution range is insufficient to deform the gas fiber stream, i.e. the force developed in this way is This is insufficient for mixing gaseous fiber streams containing large amounts of fiber per unit volume. As a result, a uniform velocity range distribution is not achieved in the deformed gas fiber flow.
Moreover, the fiber concentration of the stream fed onto the flat screen continues to decrease, as a large amount of gas is removed through the screen and the fiber layer deposited on it, during the fiber formation process. This results in increased power consumption spent to overcome the resistance developed on a flat screen.

The gas fiber stream can be deformed using simultaneous lateral pulsations and multifiber dispersion effects introduced into the gas fiber stream.

Methods for producing fibrous sheet materials are known in the art.

In this method, fibers are dispersed in a gas stream to obtain a gas fiber stream, which is then distributed in a flat shape. The resulting flat gas fiber stream is transformed by feeding it into a cylindrical element. The action of the cylinder and the flat shaped gas fiber stream results in a multi-fiber dispersion effect from the elastic repulsion of the fibrous solids against the cylindrical surface.

Therefore, a crushing of the fiber solids, ie an increase in the dispersion value, takes place. A cylinder incorporated into the device provides a lateral pulsation to the gas fiber stream flowing over the cylinder, resulting in a uniform distribution of the velocity range of the flow.

The modified gaseous fiber stream is fed onto a flat screen to form a fiber layer thereon. The fibrous layer is subjected to subsequent processing to form the finished sheet material. The apparatus for carrying out the method for producing fiber sheet material described above consists of a long slot nozzle with two right-angled side walls that diverge from each other and two front walls that converge, the inlet opening of this nozzle being adapted to obtain a gaseous fiber mixture. An outlet opening is connected to the chamber, which communicates with a device for dispersing the fibers into a gas stream.

A cylinder located below the long nozzle along its entire length is fixed at both ends to the side walls of the chamber. A special lattice for removing flow disturbances is placed downstream of the cylinder and spans the cross section of the chamber. The layer forming process is
It is carried out on a flat screen with the help of a suction box placed at the bottom of the chamber.

A disadvantage of the above method for producing fibrous sheet material and the equipment for carrying out this method is that the equipment is
It is only possible to transform a gaseous fiber stream with a fiber concentration of only 77Z3. When the gas fiber stream is fed onto the cylinder, lateral pulsations in the gas fiber stream flowing past the cylinder occur, and the force of the pulsations gradually decreases as the flow leaves the cylinder. Therefore, when a gaseous fiber stream with high fiber concentration is fed into a cylinder, the forces in the distribution range and the lateral pulsations are insufficient to deform the flow and to obtain a structurally homogeneous sheet material. That's enough. None of the above flow modification devices are capable of creating the desired degree of modification of a flow having a high fiber concentration. As a result, only a gaseous fiber stream with a low fiber concentration can be fed onto a flat screen to produce structurally homogeneous sheet material.

This results in increased power consumption since a large amount of gas is removed per unit time during the layering process. The main objective of the present invention is to transform the gaseous fiber stream with high fiber concentration to create a structurally homogeneous fiber layer on a flat screen, increasing the production yield and removing per unit time during the layering process. Provides a method for producing fiber sheet material and an apparatus for implementing this method, which reduces power consumption by reducing the amount of gas, and reduces the size of the apparatus and the consumption of metal materials necessary to make it. It is to be.

With the above-mentioned main objectives, the method for producing fibrous sheet material provided according to the present invention comprises: dispersing fibers in a gas stream to create a gaseous fiber stream; and feeding the gaseous fiber stream onto a flat screen. and removing gas from the gaseous fiber stream through the screen to form a fibrous layer on the screen, and subsequent processing to produce a fibrous sheet material. Before feeding the gaseous fiber stream onto the flat screen to achieve a fiber concentration of 20 to 500 V/I, a portion of the gas is removed from the gaseous fiber stream and the concentration is determined by the type and nature of the fibers. and is characterized in that it eliminates transverse pulsations introduced into the gas fiber stream during its movement.

The gaseous fiber stream is modified by the method described above and its fiber concentration ranges from 5 to 50 f7/m' to 20 to 500 y/m'.
increase to i.

This is caused by the presence of movement of the fibers relative to the gas,
This causes the fibers to become more regular with each other,
resulting in an increase in local fiber concentration. This allows the part of the gas expelled from the fibers to be removed, regardless of the part of the gas that is saturated with the fibers. By extinguishing the lateral pulsations introduced into the gas fiber stream during its movement, a sheet material with a homogeneous structure is obtained, which increases in the gas fiber stream as the fiber concentration of the gas fiber stream increases. This is achieved by eliminating the localized flocculation that occurs.
It is a good idea to keep the amount of gas removed from the gas fiber stream before feeding it onto a flat screen within the range of 20 to 90%.

It is also desirable to eliminate lateral pulsations by constricting the gas fiber flow in a direction perpendicular to the flow path. Contracting the gas fiber stream in a direction perpendicular to the flow path creates a turbulent stream of flow with a uniform distribution of velocity ranges.

This contributes to thickening the uniformly ordered fibers and reducing the lateral flow component of the flow disturbance. The device for carrying out the method for producing fiber sheet material provided according to the invention with the above-mentioned main purpose comprises a slot nozzle having both side walls perpendicular to the front walls which converge, and an inlet opening of this nozzle which is arranged in a gas flow direction. connected to a device for dispersing fibers; the outlet opening of the nozzle communicates with a chamber; and a flat screen supported in the chamber for forming a fiber layer on top. , a suction box placed below the flat screen, the side walls of the slot nozzles being parallel to each other, and the device for removing a portion of the gas fiber stream comprising:
Disposed in the chamber below the outlet opening of the slot nozzle, the chamber is characterized in that it is provided with a branch pipe supported substantially in the upper part of the chamber for gas evacuation.

The parallel arrangement of the two side walls of the slot nozzle eliminates a significant extension of the velocity range, ie creates a uniform distribution of the velocity range.

By providing a device arranged below the outlet opening of the slot nozzle for removing part of the gas from the gas fiber stream, the removal of gas takes place through a branch pipe arranged in the upper part of the chamber. This increases the fiber concentration of the stream and reduces the power consumption spent separating the gaseous fibers during the fiber layering process.

According to an embodiment of the invention, the devices for removing part of the gas from the gas fiber stream are arranged 3 to 20 meters above and below each other.
It is implemented as a number of parallel guides spaced apart by 77Z, arranged below one of the front walls of the slotted nozzle and inclined at an angle of 3.5° to 11° with respect to the axis of the slotted nozzle. Each of the guide bodies is inclined to the axis of the slot nozzle at an angle of 10° to 35° in the direction of movement of the gas fiber stream.

made as a number of guide bodies arranged parallel to each other above and below to form a vertical row arranged below one of the front walls of the slot nozzle and inclined at a special angle to the axis of the slot nozzle; A device for removing a portion of the gas from a liquid gas fiber creates a resistance to the flow of gas fibers exiting the outlet opening of a slotted nozzle, thereby causing a portion of the gas to change its initial direction. However, as the gaseous fiber stream flows along the row of guides, it is gradually removed as it passes through the gaps between the guides. By means of the gradual removal of gas through the gaps between the guide bodies, the fiber concentration of the stream is increased, which contributes to a uniform distribution of the velocity range of the gas fiber stream.

Due to the inclination of the row of guides with respect to the axis of the slot nozzle, the gas fiber stream is constricted as it flows along the guide, increasing the homogeneity of the gas fiber stream. According to another embodiment of the invention, the devices for removing part of the gas from the gas fiber stream are arranged one above the other.
It is constructed as a number of guide bodies arranged parallel to each other with a spacing of 0.01 mm and arranged to form two vertical rows, each of said rows being arranged below one of the front walls of the slot nozzle. and 3.5 to the axis of the slot nozzle
each of the guides is inclined at an angle of 10° to 35° in the direction of movement of the gas fiber stream with respect to the axis of the slot nozzle, the guides of one row being It is in a symmetrical position with respect to the column guide.

Guide bodies arranged one above the other and parallel to each other forming two vertical rows are combined in a device for removing a portion of the gas from the gas fiber stream, each of said rows forming a front wall of the slot nozzle. The design, which is located below one of the Make it.

The converging position of the guide body causes a contraction of the gas fiber stream in a direction perpendicular to the direction of movement of the gas fiber stream, thereby partially canceling out lateral pulsations.

It is a good idea to make the guide body in the shape of an airfoil.

The airfoils of the guides prevent the gas fiber flow from fiber loss when a portion of the gas is removed.

Each row of guides forming at least two groups of wings, with equal gaps between the guides in each group, and with the gap between the guides in the upstream group being larger than the gap between the guides in the downstream group. It is a good idea to place them. 2 guides in each row
By providing two groups, the guide bodies in each group are
Equally spaced from each other, the gaps between the guides in the upstream group are larger than the gaps between the guides in the downstream group, so that when the gas fiber stream flows along the row of guides, there is no loss of gas without fiber loss. Some removal is ensured.

The gap between the guide bodies in the upstream group should not exceed 20 mm, and the gap between the guide bodies in the downstream group should not be less than 3u.

The invention will be explained in more detail below with reference to embodiments shown in the accompanying drawings.

The method for producing fibrous sheet material is illustrated by the row diagram shown in FIG.

The fiber material and the gas are fed to a device 1 for dispersing the fibers in a gas stream, whereby a gaseous fiber stream 2 is obtained.

The resulting gas fiber stream 2 is fed into the chamber 4 through the slot nozzle 3. Within the chamber 4, the gas fiber stream 2 is contracted and the relative motion of the gas and fibers is developed by inertial forces. When the gas fiber stream is contracted, the gas and fibers move in different directions because the density of the fiber material is 800 times the density of the gas. The fibers migrate along a path that corresponds to the initial path of the gas fiber stream 2, and a portion of the gas without fibers begins to move in a direction opposite to the initial path of the gas fiber stream 2. Some of the gas is removed and the fiber concentration of the stream increases. The flow path of the gas portion whose direction of movement has been changed is indicated by arrow a. The gas fiber stream 2 is contracted in a direction perpendicular to its direction of movement, whereby the transverse pulsations introduced into the gas fiber stream gradually disappear.

Uniformity of the velocity range of the fiber material in the gas fiber flow and small disturbance structures are thus achieved. This in turn ensures a high fiber concentration and at the same time a homogeneous structure of the gaseous fiber flow passing through the chamber 4. The gas fiber stream 2 is further fed from the chamber 4 onto a flat screen 5, from where the remaining part of the gas is removed by a suction box 6 supported below the flat screen 5. The direction of the portion of gas removed from the gas fiber stream when placed on the flat screen 5 is indicated by arrow c.

The fibrous layer placed on the flat screen 5 undergoes special processing to create the finished fibrous sheet material. The portion of gas removed from the gas fiber stream 2 in the chamber 4 and removed from the flat screen 5 has a fiber content in the gas of 0.02 to 0.5 y/r? ? Therefore, it can be reused by feeding a portion of said gas into the device 1 for fiber dispersion without further removal of the fibers from the gas.

Therefore, the problem of environmental protection is effectively solved. The portion of gas removed from the gas fiber stream 2 in the chamber 4 is 20
90%. The amount of gas removed from the gaseous fiber stream 2 is selected according to the desired mass of finished fiber sheet material 1 and the length of the fibers fed into the dispersion device 1.

The mobility (MO) of fibers with a length of 0.5 to 38
When an amount of gas of 20 to 40% is removed, fiber sheet materials with high structural homogeneity with a mass of 12 to 40 V/I are obtained.

40 to 100 y/? when 40 to 60% of the gas is removed from the gas fiber stream 2, if a low mobility of fibers with a length of 0.5 to 38 mm is allowed. r?
A homogeneous fibrous sheet material is formed having a mass of .

If the mobility of the fibers in the gas fiber stream 2 is even lower, when 60 to 90% of the gas is removed from the gas fiber stream 2, 100 y/w? A homogeneous fiber sheet material having a mass of more than 10% can be produced.

If the amount of gas removed is less than 20%, the method does not consume power.

The power increases greatly due to the significant amount of gas removed per unit time. It is then not possible to remove more than 90% of the gas from the gas fiber stream 2.

The device for carrying out the method for producing fiber sheet material consists of a tube 8 (FIG. 2) connecting the device 1 for dispersing the fibers in a gas stream and the inlet opening of the slot nozzle 3.

The slot nozzle 3 has parallel side walls 9, 10 (FIG. 3) at right angles to converging front walls 11, 12. The outlet opening of slot nozzle 3 communicates with chamber 4 . In the chamber 4 below the front wall 11 of the slot nozzle 3 a guide body in the form of a wing 13 (
(Fig. 2) is provided.

The wings are arranged parallel to each other, spaced above and below each other, and the gap 14 between them is between 20 and 3 degrees. The gap 14 between the wings 13 is selected according to the length of the fibers used in the layering process. If the fiber length is 2 mm and less, the gap 14 is selected from 10 to 3 mm, and when the fiber length is 20 to 35 mwL, the gap 14 is selected from 10 to 3 mm.
4 is 10 to 20 degrees. The blades 13 are inclined at an acute angle α to the axis of the slot nozzle 3 in the direction of flow movement. The angle α is selected according to the mass of the fiber material and the elasticity of the fibers.

If the fibers have suitable elasticity and the mass of the fiber material is sufficient, significant inertial forces are generated in the gas fiber stream 2 as it moves along the airfoils 13. Wings 13
In order to prevent fiber loss of the gas fiber flow 2 occurring through the interstices 14, the fibers are repelled against the airfoil surface towards the axis of the chamber 4. Moreover, such an angle α creates an additional resistance caused by the wings 13 to the gas fiber flow 2, which enhances the way in which a portion of the gas is removed from the gas fiber flow 2. The fiber has low elasticity and its mass is small,
If a reduced inertial force is developed in the gas fiber stream 2 as it moves along the airfoil 13, the angle α is set close to 10° and the appropriate amount of energy reflected from the airfoil surface along the airfoil 13 is set. Creates smooth movement of non-elastic fibers.

Moreover, such an angle α creates a negligible additional resistance of the blade to the gas fiber flow 2, which eliminates fiber loss when gas is removed. The wings 13 are fixed at their ends to the side walls 9, 10 (FIG. 3) of the chamber 4, the length of each wing being equal to the distance between the side walls 9, 10 of the chamber 4.

The vanes 13 form a vertical row oblique to the axis of the slot nozzle 3 at an angle β (FIG. 5) selected within the limits of 3.5° to 10°.

The number of angles β is set to enhance the removal of gas if a sharp build-up of blade resistance to the gas fiber flow 2 occurs. High-intensity gas removal from the gas fiber stream 2 only takes place if the mass of each fiber is sufficient, for example if fibers with a significant length or density (asbestos fibers) are used. In this case, the inertial force acting on the fibers in the gas fiber flow 2 is large, so that the fiber loss due to gas removal cannot be ignored. Setting the rows of blades at an angle β greater than 11° contributes to excessively strong gas removal and results in some fiber loss with gas removal.

If the fibers are short or have a low density, for example hollow fibers, the inertial forces acting on them are small.

In this case, strong gas removal is not possible since a large amount of fiber material is lost. Therefore, the gas removal method should be carried out with low intensity, ie low resistance to the gas fiber flow 2. The angle β to satisfy these requirements is close to 3.5°. room 4
A branch pipe 15 (FIG. 2) is connected to the upper part of the pipe.

A flat screen 5 is below the chamber 4. A suction box 6 is placed below the flat screen 5. The fibrous layer formed on the flat screen 5 is subjected to post-processing to produce the finished sheet material. supplied to 6th and? The figure shows another embodiment of an apparatus for the production of fiber sheet material, in which the apparatus for removing part of the gas from the gas fiber stream 2 is arranged in large numbers to form two vertical rows. are made as wings 13, and each row is
It is placed below one of the front walls 11, 12 of the slot nozzle 3 and is inclined at an angle of 3.5° to 11° with respect to the axis of the slot nozzle 3.

The blades 13 forming one row arranged below the front wall 11 are arranged below the front wall 12 of the slot nozzle 3.
It is placed symmetrically with respect to the wings 13 forming the row.

The blades 13 in each row are supported vertically and parallel to each other,
and placed at intervals of 3 to 20 mwL, and each blade 13 is
It is inclined to the axis of the slot nozzle 3 at an angle of 10° to 35° in the direction of movement of the flow. Figures 8 and 9 show a further embodiment of an apparatus for the production of fibrous sheet material, in which each row of wings 13 is divided into two sections I and ■.

Category I is above category ■. The gap 14 between the blades 13 of section I is set to 20 to 10 mm, and
The gap between the blades 13 in category (2) is set to 10 to 3 inches. FIG. 10 shows yet another embodiment of an apparatus for producing fibrous sheet material, in which each row of wings 13 comprises four
It is divided into three categories □, ■', V and ■.

The gap 14 between the blades 13 in section I is set to 20 to 17 degrees, and the gap 14 between the blades 13 in section II is set to 16 to 1.
The gap 14 between the blades 13 of the section V is set to 11.
The gap 14 between the blades 13 in category (2) is 6 to 3 meters! It is set to n. When setting the gaps between the blades in each category, the following were taken into consideration:

When the gas fiber stream 2 enters the area of section I, the fiber concentration in the gas fiber stream is low and the resistance exerted by the fiber material to the lateral flow of gas during gas removal is also low. Moreover,
Due to the high mobility of the fibers resulting from the low fiber concentration above section 1, the inertia of each fiber particle is clearly greater than on the next section. To that end, a stronger removal of gas is ensured in the area of section I, and a large gap between the blades 13 is provided practically without fiber loss. Gas fiber flow 2 is class I
The fiber concentration of the gaseous fiber stream 2 increases as it passes through the area and enters the area of segment (2). Due to the increased fiber concentration, the resistance to lateral gas flow increases in segment ■.

The same is true in response to the low mobility of the fibers, which occurs under the action of inertial forces. Therefore, the potential for fiber loss with gas removal increases. However, category H
The gap between the blades 13 is small, which results in a low gas removal rate and reduced fiber loss.

Therefore, by changing the gap between the blades 13 of each section,
Gas removal is controlled over the entire length of the row of blades 13.

The fibrous sheet material production apparatus described above operates as follows.

The fibers are placed in a device 1 for dispersing the fibers in a gas stream (
Figure 6). The resulting gas fiber stream 2 is transferred to the tube 8
through which it is fed to the inlet opening of the slot nozzle 3. Converging front walls 11, 12 and parallel side walls 9, 10 (seventh
With the arrangement in Figure), the cross-sectional area of the slot nozzle 3 is reduced, whereby the velocity of the gas fiber stream 2 when it leaves the slot nozzle 3 is increased. At the same time, the gas fiber stream 2 is contracted, which results in a uniform distribution of its velocity range. The gas fiber flow 2 is passed through the slot nozzle 3 (Fig. 6).
Upon exiting the airfoil 13, it encounters resistance created by the converging rows of wings 13.

As a result, a significant portion of the gas changes its direction of movement, heads into the gap 14 between the wings 13, enters the chamber 4 and is then removed from the device through the branch 15. Since the density of the fibers is significantly greater than the density of air, the fibers continue to move linearly between the converging rows of blades 13 under the action of inertial forces.

Some of the fibers that contact the wing surface impinge on the wing surface and are repelled from the wing surface by the orientation of the wing, which is aligned at an angle to the axis of the slot nozzle 3, and Move towards the central part of the space formed by the two converging columns. As gas is gradually removed through the gaps 14 between the vanes 13, the fiber concentration of the gas fiber stream 2 increases.

The convergent arrangement of the rows of vanes 13 for the contraction of the gas fiber stream 2
This contributes to increasing the homogeneity of the flow. A high fiber concentration in gaseous fiber stream 2 reduces fiber mobility. The gaseous fiber stream 2 is deformed and fed to the moving screen 5 soil to meet the requirements imposed to create a homogeneous structure of fiber sheet material passing between the rows of blades 13.

When the gas fiber stream 2 contacts the flat screen, the remaining part of the gas is removed by the suction box 6, thereby
The fibers are deposited on a flat screen 5 to form a structurally homogeneous fiber layer.

The resulting layer is fed to a device 7 for processing to create a homogeneous fibrous sheet material. Example 1 A sheet material with a mass of 105V/Rn″ has a mass of 2.5
Produced from asbestos fibers with mm mode length.

(a) Fiber concentration in gas fiber flow 50y/m゛(b)
Velocity of the gas fiber flow 10 m/s (c) Component of the lateral flow of the gas fiber flow disturbance 20% (d) Air is used as the gas.

(e) 105y/Rr? Since the fiber material is obtained from short fibers, 80 to 90% of the gas content is removed.

The device for removing a portion of the gas from the gas fiber stream comprises: 2
It is implemented as a number of wings forming two vertical rows, each row being located below one of the front walls of the slot nozzle.

Each vane is inclined at an angle of 10° to the axis of the slotted nozzle, and each row of vanes is inclined at an angle of 11° to the axis of the slotted nozzle.
It is tilted at an angle of °. The maximum angle of row inclination and the minimum angle of blade inclination with respect to the slot nozzle axis are:
Selected to create strong removal of gas from the gas fiber stream as it moves between the rows of vanes.

Each row of wings is divided into four sections.

Viewed from the nozzle, the first three sections are of equal length. The length of the fourth section is equal to 1.2 times the length of the first section. The gap between the wings of the first section is equal to 12 seams, the gap between the wings of the second section is equal to 6mm, the gap between the wings of the third section is equal to 6mm, and the gap between the wings of the fourth section is 3m.
Equal to m. The provision of four sections, each with a different clearance between the blades, ensures smooth removal from the gas fiber stream.

The loss of asbestos fibers, which contain a significant amount of small sized fragments, is insignificant. Even though the length of the fibers is small, the mass of the asbestos fibers is large, so the gap between the wings of the first section is set much larger than the length of the fibers.
can do. In this case, a significant inertial force is developed in the gas fiber stream as it moves along the airfoil of the first section, and this inertial force prevents fiber loss. A gas fiber stream is fed to the slot nozzle at a speed of 10 m/s.

When the gas fiber stream leaves the slot nozzle, its velocity is
The converging front wall increases it to 15 m/s. As the gas fiber stream moves between the rows of blades, the gas is partially removed from it, 50% of the gas is removed in the first section, 30% in the second section, and 15% of the gas is removed in the second section. % is the third
5% is removed in the fourth section. The total amount of gas partially removed from the gas fiber stream is 100%. The gas removed from the gaseous fiber stream is supplied from the chamber through a branch to a device for dispersing the fibers in the gas stream. Total fiber loss does not exceed 10%. As a result of removal of 80 to 90% of the gas, the fiber concentration in the gas fiber stream reaches 250 to 500 v/1 and the lateral flow is characterized by a lateral flow component of the strength of the gas fiber flow disturbance. The pulsation drops to 5-8%, which creates a homogeneous structure of the gas fiber flow.

The gas fiber stream moving with a speed of 15 m/s is further fed onto a flat screen moving with the same speed.

The remaining 10-20% of the gas is removed by a suction box and placed on a flat screen at 70y/Rr? form a fibrous layer with a mass of

The fiber layer was then impregnated with a 3% silicone emulsion to 105y/Rr? made of a material with a mass of
Rolled and dried to 2% temperature. The finished sheet material has high thermal and electrical resistance and can be advantageously used in the electrical industry. Example 2 110V/w? A sheet material having a mass of 1 is made from sulfate bleached cellulose with a fiber mode length of 1.5 mw1.

(a) Fiber concentration 50y/Rr in gas fiber flow? (b
) Air is used as the gas and contains 10% carbon dioxide to prevent the gas fiber mixture from exploding due to electrostatic charge effects.

(c) Speed of gas fiber flow 8 m/s (d) lateral flow component of gas fiber flow disturbance strength 251y
17110y/Rr? In order to obtain a material having a mass of , an amount of gas of 60 to 80% is removed.

The device for removing a portion of the gas from the gas fiber stream comprises: 2
It is implemented as a number of wings forming two vertical rows, each row being located below one of the front walls of the slot nozzle. Each vane is angled at an angle of 10° to the axis of the slotted nozzle, and each row of vanes is angled at an angle of 3.5° to the axis of the slotted nozzle. The row of blades and the minimum angle of inclination of each blade with respect to the axis of the slot nozzle are:
Selected to create strong removal of gas from the gas fiber stream as it moves between the rows of blades.

Each row of wings is divided into three sections of equal length.

The gap between the blades of the first section is equal to 11 mm, the gap between the blades of the second section is equal to 9 mm, and the gap between the blades of the third section is equal to 4 mm. Cellulose fibers have a smaller amount of fragments than asbestos fibers, so it is sufficient to divide the row of blades into only three sections, allowing gas removal to occur with less smoothness.

The gaps between the wings of each section ensure strong removal of gas without significant fiber loss.

A gas fiber stream is supplied to the slot nozzle at a speed of 8 m/s.

When the gas fiber stream exits the slot nozzle, its velocity is 10
m/s. As the gas fiber stream transitions between the rows of blades, the gas is partially removed from there, leaving 50% of the gas
5% of the gas is removed in the first section, 30% of the gas is removed in the second section and 7% of the gas is removed in the third section. The total amount of gas partially removed from the gas fiber stream is 100%. As a result of 60 to 80% removal of gas, the fiber concentration in the gas fiber stream is 125 to 250 y/w
? As the gas fiber flow increases, the lateral pulsation of the gas fiber flow drops to 4-6%, which creates a homogeneous structure of the gas fiber flow.

The gas fiber stream moving at a speed of 10 m/s is further fed onto a flat screen moving at the same speed.

The remaining part of the gas, between 20 and 40%, is removed by a suction box and is 90,/Rr? A layer of cellulose fibers having a mass of is formed on a flat screen.

The fibrous layer was impregnated with a 3% solution of prepared corn starch, bringing the mass of the material to 110 y/w? It is then rolled and dried to make wrapping paper. Example 3 A sheet material with a mass of 40 y/y is made from viscose fibers with a fiber mode length of 8 y/y.

(a) Fiber concentration 25y/m' in gas fiber flow (b)
Use air as the gas.

(c) Velocity of gas fiber flow: 6 m/s (d) Transverse flow component of gas fiber flow disturbance strength: 38% Bisrose fiber is long and 40V/Rr? of material is obtained, so that 50 to 60% of the gas amount is removed.

The device for removing a portion of the gas from the gas fiber stream comprises: 2
It is implemented as a number of wings forming two vertical rows, each row being located below one of the front walls of the slot nozzle.

Each vane is angled at an angle of 15° to the axis of the slotted nozzle, and each row of vanes is angled at an angle of 7° to the axis of the slotted nozzle. Since viscose fibers do not have adequate elasticity, the slope of the blades at an angle of 15° to the axis of the slotted nozzle allows the fibers to glide smoothly along the blades, while also providing a slope of 7° to the axis of the slotted nozzle.
The inclination of the blade rows at an angle of .degree. ensures an adequate degree of gas removal from the gas fiber stream.

Each row of wings is divided into two sections of equal length.

The gap between the wings of the first section is 10! ! equal to Iln, the second
The gap between the wings of the division is 5r! Equal to 1m. A gas fiber stream is fed to the slot nozzle at a speed of 6 m/s. When the gas fiber stream leaves the slot nozzle, its velocity is 8 m/
increases to s. When the gas fiber flow passes between the rows of blades,
The gas is partially removed from there and 60% of the gas
% of the gas is removed in the first section and 30% of the gas is removed in the second section. The total amount of gas removed from the gas fiber stream is 10
It becomes 0%. As a result of the removal of 50-60% of the gas, the fiber concentration in the gas fiber stream increases from 25 V/77z' to 50-64 y/m' and the lateral pulsation of the gas fiber stream increases due to flow convergence. , falls to 7%, creating a homogeneous structure of the gas fiber flow.

A gas fiber stream moving at a speed of 8 m/s is fed to a flat screen soil moving at the same speed.

The remaining part of the gas, 40 to 50%, is removed by a suction box, 30y/w? A layer of viscose fibers with a mass of
Rr? increases to

This material is rolled and dried to form a non-woven oil permeable material for large diesel engines. Example 4 20y/w? A sheet material having a mass of , is made from a polyester man-made fiber with a mode length of 28 mw1.

(a) Fiber concentration in gas fiber flow 8y/? 7-? (Turn) Use ionized air as the gas.

(c) Velocity of gas fiber flow 7 m/s (d) Component of lateral flow of gas fiber flow disturbance strength 35% 20y/Rr? Since a fiber sheet material having a mass of 20 to 2
5% of the gas volume is removed.

The device for removing part of the gas from the gas fiber stream is made as a number of vanes forming one vertical row arranged below one of the front walls of the slot nozzle, with a gap between the vanes of 20 mm. equal.

Each vane is angled at an angle of 35° to the axis of the slotted nozzle, and the row of vanes is angled at an angle of 3.5° to the axis of the slotted nozzle. The blade rows and the angle of inclination of each blade relative to the axis of the slot nozzle are selected to ensure removal of small amounts of gas without substantial fiber loss. A gas fiber stream is fed to the slot nozzle at a speed of 7 m/s.

When the gas fiber stream leaves the slot nozzle, its velocity is 1
As high as 0 m/s. As the gas fiber stream moves along the wing, 20% of the gas is removed therefrom. As a result of 20% removal of gas, the fiber concentration in the gas fiber stream is 16 V/w? From 21,/w? rise to The lateral flow component of the disturbance strength drops to 12% due to the convergence of the gas fiber flow. A gas fiber stream moving at a speed of 15 m/s is fed onto a flat screen moving at the same speed.

The remainder of the gas, ie 80% of the gas, is removed from the gas fiber stream by the suction box, forming a layer of man-made fibers with a mass of 15,/i. This layer was impregnated with a 5% solution of polyvinyl alcohol, 20y/Rr? A material with a mass of is made and then rolled and dried. The finished material is vertical paper (10 mg
rainpaper). Example 5 500,/? A sheet material with a mass of 71'' is made from dissociated wood fiber granules.

(a) Fiber concentration in gas fiber flow 50y/7r? (b
) Velocity of the gas fiber flow 8 m/s (c) Transverse flow component of disturbance strength 32% (d) Air is used as gas.

(e) 100y/w? Since a fibrous material having a mass of more than 85 to 90 C$ is produced, an amount of gas of 85 to 90 C$ is removed.

The device for removing a portion of the gas from the gas fiber stream comprises: 2
implemented as a number of vanes arranged to form two vertical rows, each row disposed below one of the front walls of the slotted nozzle, each vane at an angle of 30° to the axis of the slotted nozzle. Each row of wings is tilted at an angle
It is inclined at an angle of 11° to the slot nozzle axis.

The maximum angle of inclination of each row and each vane relative to the slot nozzle axis is selected to create strong gas removal from the gas fiber stream as it flows between the rows of vanes. The wood fiber granules used in this method have a large mass and considerable elasticity, and therefore the inertial forces acting on the fiber material are large.

For the same reason, the gap between the blades is equal to 6 mwL.

A gas fiber stream is fed to the slot nozzle at a speed of 8 m/s. The velocity of the gas fiber stream when leaving the slot nozzle increases to 10 m/s. When the stream of gas and wood fiber granules flows between the rows of blades, 85 to 90% of the gas fraction is removed.

As a result, the concentration of wood fiber granules is between 334 and 5
00V/1. The lateral flow component of the disturbance strength drops to 7-10% due to the convergence of the gas and wood fiber granules flow. The flow is further fed onto the flat screen in a direction perpendicular to the plane of the flat screen. The flat screen moves at a speed of 0.8 m/s.
The remaining 10-15% of the gas is removed from the gas fiber stream by a suction box, forming a layer of wood fiber granules with a mass of 400 V/I.

The resulting layer is impregnated with a solution of phenolic resin, 50
The finished material has a mass of 0,/1. This material is 3x3
cut into sheets with dimensions of 20E7 at 180°C.
During Z, a pressure of 60 kg/1 is applied. The finished material is a fiber structure board that can be put to practical use in the engineering materials industry.

Example 6 400V/Rr? A wool felt with a mass of 1.5 wt.L is made from fibers with a mode length of 10 to 35 wtwL.

(a) Fiber concentration in gas fiber flow 40V/? ? ? (b
) Velocity of gas fiber flow 6 m/s (c) 40% component of highly disturbed lateral flow (d) Use of air as gas (e) Amount of gas removed 90% To remove part of the gas The device is implemented as two rows of wings, each row located below one of the front walls of the slot nozzle.

Each row of blades is angled at an 18° angle, and each row is angled at an 11° angle. The angle of inclination is selected according to the mass of the fiber and its elasticity.

Since the fibers are long and have a considerable mass, they can strongly remove gases. The elasticity of the fibers is very high, which is why the blade inclination angle is set at 18°. Since the mass of each fiber is sufficient to ensure a high velocity lateral flow of the gas to be removed under the action of inertial forces,
The gap between the wings is the same, equal to 10 mm.

A stream of gas and wool fibers is fed to the slot nozzle at a speed of 7 m/s.

The flow travels at a speed of 8.5 m/s as it exits the slot nozzle and passes between two rows of vanes. When the flow flows between the two rows of blades, 88 to 90% of the gas volume is removed. The concentration of fibers in the gas fiber stream is between 410 and 500,
/ Becomes I. Once a portion of the gas is removed, the gas fiber stream forms an 8
．． It is fed onto the flat screen soil at a speed of 5 m/s. The flat screen moves at a speed of 1.35 m/s and the remaining part of the gas is removed by a suction box.
As a result, a layer of fibrous material with a mass of 400 V/1 is formed on the screen.

The resulting layer is rolled up. The finished material is felt used in the textile and engineering materials industries.

Having shown and described a particular embodiment of the invention in detail,
Various modifications thereof will be apparent to those skilled in the art and the invention is therefore not limited to the described embodiments or details thereof, but rather to the invention as defined in the claims. It can be implemented without departing from the idea and scope of the above.

[Brief explanation of the drawing]

FIG. 1 is a flow diagram showing the method for producing fiber sheet material according to the present invention, FIG. 2 is a schematic overall view of an apparatus using the method for producing fiber sheet material according to the present invention, and FIG. , is a vertical sectional view of the thing shown in FIG. 2, FIG. 4 is an enlarged view of part A in FIG.
The figure is an enlarged view of part B in FIG. 2, and FIG. The figure shows the sixth
FIG. 8 is a schematic overall view of another embodiment of the apparatus for carrying out the method for producing fiber sheet material of the present invention; FIG. FIG. 10 is a longitudinal sectional view of an embodiment, and FIG. 10 is a schematic overall view of yet another embodiment of an apparatus for carrying out the method for producing a fiber sheet material of the present invention. 2: gas fiber flow, 3: slot nozzle, 4: chamber, 5: flat screen, 9, 10: side wall of slot nozzle, 1
1, 12: Front wall of slot nozzle, 13: Wing, 14:
Gap between wings, 15: Branch pipe.

Claims (1)

[Claims] 1. Dispersing fibers in a gas stream to create a gas fiber stream, feeding the gas fiber stream onto a flat screen, and removing gas from the gas fiber stream through the screen. A method for producing fibrous sheet material comprising forming a fibrous layer on the screen with a fibrous sheet and subsequent processing to produce a fibrous sheet material, wherein the fiber concentration in the gaseous fiber stream is between 20 and 500 g/m^3.
Before feeding the gaseous fiber stream onto the flat screen in order to remove a portion of the gas from the gaseous fiber stream, the concentration being chosen according to the type and nature of the fibers, and the gas being A method for producing fiber sheet material, characterized in that transverse pulsations introduced into the gaseous fiber stream during the movement of the fiber stream are eliminated. 2. In the method of producing fibrous sheet material according to claim 1, the amount of gas removed from the gaseous fiber stream before it is fed onto the flat screen is 2.
A method for producing a fiber sheet material characterized by a retention of 0 to 90%. 3. A fiber sheet material production method according to claim 1, wherein the lateral pulsation is eliminated by contraction of the gas fiber flow in a direction perpendicular to the movement path of the gas fiber flow. Material production methods. 4. a slotted nozzle with side walls perpendicular to the converging front walls, the inlet opening of said nozzle being connected to a device for dispersing the fibers in a gas stream, and the outlet opening of said nozzle being connected to a device for dispersing the fibers in a gas stream; a flat screen supported below the chamber and adapted to form a fibrous layer on its upper surface; and a suction box disposed below the flat screen. In the apparatus for carrying out the sheet material production method, both side walls of the slot nozzle are parallel to each other, and a device for removing a portion of the gas from the gas fiber stream is arranged in the chamber below the outlet opening of the slot nozzle. Apparatus for carrying out a method for producing fibrous sheet material, characterized in that said chamber is provided with a branch pipe supported substantially in an upper part of said chamber for gas discharge. 5. The device according to claim 4, wherein the device for removing a portion of the gas from the gas fiber stream is arranged below one of the front walls of the slotted nozzle and with respect to the axis of the slotted nozzle. It is constructed as a number of parallel guide bodies arranged above and below each other at a distance of 3 to 20 mm to form vertical rows inclined at an angle of 3.5° to 11°, each of said guide bodies being , inclined to the axis of the slot nozzle at an angle of 10° to 3.5° in the direction of movement of the gas fiber stream. 6. The device according to claim 4, wherein the devices for removing a portion of the gas from the gas fiber stream are arranged parallel to each other at a distance of 3 to 20 mm above and below each other so as to form two vertical rows. The guide bodies are constructed as a number of guide bodies arranged at 3.0 mm, each row being arranged below one of the front walls of the slot nozzle and 3.
Each of the guides is inclined at an angle of 5° to 11° with respect to the slot nozzle axis at an angle of 10° to 35° in the direction of movement of the gas fiber flow and the guides of one row Device characterized in that the body is in a symmetrical position with respect to the guide bodies of the other row. 7. The device according to claim 5 or 6, characterized in that the guide body is made in the shape of a wing. 8. The device according to claim 5 or 6, wherein the guides in each row are arranged to form at least two groups and to create equal gaps between the guides in each group. , wherein the gap between the guide bodies of the upstream group is larger than the gap between the guide bodies of the downstream group. 9. Device according to claim 8, characterized in that the gap between the guide bodies of the upstream group does not exceed 20 mm. 10. The device according to claim 8, characterized in that the gap between the guide bodies of the downstream group is not less than 3 mm.