DE7715011U1 - BUILT-IN DRAIN FOR PAPER MACHINES - Google Patents

Description

P 3507 J.M.VOITK GxMBK

Password: "Premixer" Heidenheim

Headbox for paper machines

Headbox for paper machines, with an inlet channel, a adjoining transverse distributors and individual channels leading away from this.

In the known designs, flocculation and segregation occur and asymmetrical flow profiles. These disturbances can affect the entire headbox and then result in fluctuations in the profile of the Paserbahn to be produced.

The invention aims to solve the problem in a constructive manner simple way to avoid flocculation, segregation and asymmetrical flow profiles, with the intended Facility should be inexpensive both to manufacture and to operate.

This object is achieved according to the invention by a mixing device arranged upstream of the transverse distributor and having at least a rotatably mounted mixer for the suspension, which can be driven by a motor.

The invention has the following advantages:

It causes the flakes to be removed or the suspension fed in to be homogenized; it gives me a good flow profile and a good material distribution immediately after the mixing elementj the mixing element requires little energy to drive it; the structural design is inexpensive and requires little maintenance; the

7715011 12/07/78

Mixing device requires little space and can also be used at deflection points the suspension flow can be arranged.

Several embodiments of the invention are discussed below :

In order to save energy for the motor, it is expedient to also use the suspension flow hydraulically to operate the mixing element to drive. A drive rotor arranged upstream of the mixing element in the suspension flow can serve for this purpose Guide surfaces, e.g. vanes, are set in rotation by the suspension flow around the rotor axis, whereby the drive rotor with the mixing element is connected in such a way that it drives it. This can be done in a very simple manner in that the mixing element is provided on its upstream side with these guide surfaces and thus forms a unit with the drive rotor.

The mixing element can be a disk-like one that is permeable to the suspension Be an element, for example an impeller, a perforated disk or a slotted disk, the disk plane of which is transverse to the flow channel, while its axis of rotation runs axially to the flow channel.

Notwithstanding this, the mixing element can be essentially cylindrical Be a rotor whose jacket is permeable to the suspension and whose cylinder axis, which is also the axis of rotation is, perpendicular to the main direction of movement of the incoming and / or outgoing suspension.

In order to avoid undesired transverse or eddy currents, it is expedient for the mixing device to be located downstream of the mixing element has arranged guide device which aligns the suspension swirled by the mixing element in a uniform Direction of flow causes.

7715011 12/07/78

• · »2 · χ η ·

• · - ■ O W ·

The guide device expediently has a plurality of Passages through which the suspension is broken down into individual streams that are parallel to one another. This can be done in a simple way Way done by using a perforated plate.

In connection with a mixing element designed as a cylindrical rotor, it is useful if the guide device has an im essential cylindrical guide body (strainer), the jacket of which has said plurality of passage openings and meshes with the jacket of the cylindrical mixing element. Since the guide device downstream of the mixing element to the effect must come, depending on the direction of flow, the cylindrical guide body will either be located within the cylindrical mixing element or surround it.

The mixing device should be less than 5 ro (flow path) before be arranged the transverse distributor and is conveniently located directly at its inlet. This ensures that the suspension has the desired uniformity when it flows through the transverse distributor.

It is particularly advantageous if the transverse distributor is essentially runs at right angles to the inlet channel, the axis of rotation of the mixer element runs essentially axially to the transverse distributor and this axis of rotation is received by a bore in the duct wall on the side of the mixing element facing away from the transverse distributor.

To ensure trouble-free operation, it is advisable to Take measures to clean the mixing device. A simple measure can consist in designing the mixing element and the guide device in such a way that they are in contact with one another Can be brought into contact in order to remove adhering suspension particles by the rotating mixer.

7715011 12/07/78

> (fit 1 I I S I. * I I

I I I I I ι

For removing and dissolving accumulations of suspension particles (Fibers), it is advantageous if the mixing element is optionally equipped with a stripping device arranged upstream of it accumulating suspension particles can be brought into plant. The mixing device can be cleaned structurally easily achieved in that the mixing element is mounted axially displaceably.

Two embodiments of the invention are shown as examples in the drawings and are described below.

Show it:

Fig.l a schematic, broken representation of the headbox, partly in axial section, and

2 shows a further embodiment of the headbox, also partly in axial section.

In Fig.l an inlet channel 1 for the suspension is connected via a manifold 2 to a transverse distributor 3, of which several Individual channels 4 lead to a nozzle 5 of the headbox, shown only broken off. The arrows show the direction of flow the suspension.

In the leg of the manifold 2, which is connected to the inlet 6 of the transverse distributor 3 is connected, there is a perforated plate 7 acting as a guide device upstream of this perforated plate 7 a mixing element 8 designed as a perforated disk is arranged, the axis of rotation 9 of which runs axially to the transverse distributor 3. The mixing organ 8 is on the one hand by a motor not shown (corresponding to the motor shown in Fig.S) and on the other hand by driven by a hydraulic drive. In the exemplary embodiment, the hydraulic drive consists of an axially in the inlet channel 1 housed drive rotor 10, which is driven by the suspension flow and its driving force via gears on the Shaft 9 of the mixer 8 transmits.

7715011 12/7/76

In order to remove and dissolve accumulations of fibers in the suspension, the mixing element 8 is mounted axially displaceably in the bend 2, so that it can be brought into contact with the perforated plate 7. On the side of the mixing element 8 facing away from the perforated plate 7 a slide 11 is provided. This rests against a stop and can counter the force of a compression spring 13 »with the upstream wärtigen side of the mixer 8 are brewed in contact in order to scrape off fiber accumulations there.

In the embodiment according to Figure 2, the inlet channel 21 is a Angle connection piece 22 connected to the transverse distributor 23. The guide device for the suspension is formed by a substantially cylindrical screen basket 27 which is axially to Cross distributor 23 is arranged at its inlet 26. The sieve basket 27 sits within a substantially cylindrical mixing element 28, whose shaft 29, which is also axial to the transverse distributor 23 is driven by a motor 30. The cylindrical shell of the mixer is permeable to the suspension. The coat can consist of a sieve or perforated sheet metal or else in the form of rotor blades 31 which extend essentially axially to have.

Heidenheim, 05/03/77
EVe / Rä

7715011 12/07/78

Claims (1)

Pertrerrog Proverbs Headbox for paper machines, with one inlet channel, an adjoining transverse distributor and individual channels leading away from it, characterized by an upstream the transverse distributor (j5) arranged mixing device with at least one rotatably mounted mixing element (8; 28), which can be driven by a motor QO). 2. Headbox according to claim 1, characterized in that the mixing element (8) in addition to the motor drive (30) can also be driven hydraulically (10) by the suspension flow. Headbox according to claim 2, characterized by a upstream of the mixing element (8) in the suspension flow arranged drive rotor (10), the guide surfaces of the Suspension flow set in rotation around the rotor axis and that the drive rotor is connected to the mixing element in such a way that it can drive it. Headbox according to one of Claims 1 to 3, characterized in that that the Mischoz'gan (8) is a permeable for the suspension, disk-like element, for example an impeller, a perforated disk or a slotted disk, the disk plane of which lies transversely to the flow channel, while whose axis of rotation (9) runs axially to the flow channel. 7715011 12/07/78 j 5 «Stock on barrel according to one of Claims 1 to J>, characterized in that the mixing element (28) is an essentially cylindrical rotor, the jacket of which is for the suspension ] is permeable and its cylinder axis (29), which is equal ; is an early axis of rotation, perpendicular to the main direction of movement · ■ the incoming and / or outgoing suspension ) runs. 6. Headbox according to one of claims 1 to 5, characterized in that that the mixing device is a downstream of the ': Mixing element (8; 28) arranged guide device (7; 27) J, -ν having an orientation of the swirled by the mixing element Suspension caused in a uniform flow direction. 7. Headbox according to claim 6, characterized in that the guide device (7; 27) has a plurality of passage openings through which the suspension in each other parallel individual streams is broken down. 8. Headbox according to claim 7, characterized in that the guide device has a perforated plate (7) provided with the passage openings. 9. Headbox according to one of claims 5 to 8, characterized in that that the guide device has a substantially cylindrical guide body (27), the jacket of which is mentioned Has a plurality of passage openings and with the jacket of the mixing element designed as a cylindrical rotor (28) interlocks. 10. Headbox according to one of claims 1 to 9, characterized in that that the mixing device is arranged less than 5 m (flow path) in front of the transverse distributor (3). 7715011 12/07/78 11. Headbox according to claim 10, characterized in that that the mixing device is arranged at the inlet of the transverse distributor (3). 12. Headbox according to claim 11, characterized in that the transverse distributor (3) runs essentially at right angles to the inlet channel (l) that the axis of rotation (9; 29) of the Mixing element runs essentially axially to the transverse distributor (3) and that this axis of rotation is on the one facing away from the transverse distributor Side of the mixing element (8j 28) is received by a bore in the channel wall. . ee indicated that cleaning measures have been taken in the direction. l4. Headbox according to ^ ßjaspfuch 13, characterized in that the misoperation brought into contact with the guide device a. ^ 4 ^ di fabric on the run according to claim 1% »^ it? 1r%, characterized in that the part of the mixing element (8) which is permeable to the suspension can be brought into contact upstream with a stripping device (11, 12, 13) for any suspension particles that may collect. J.-6. Headbox according to one of Claims 13 b * e- = i57 thereby characterized in that the mixing element (8; 28) is mounted so as to be axially displaceable. Heidenheim, 05/03/77
EVe / Rä 7715011 12/07/78