FI64673B - ETAGEINLOPPSLAODA FOER PAPPERSMASKIN - Google Patents

Description

I. -'- »--- l Γβ1 ANNOUNCEMENT, Λ s Π η, Μ (11) UTLÄGGN I NGSSKRIFT ^ 4 6 Ί 3 (45) pc 5 .., .. ·. , .. (\]. t ^ ν (51) Kv.ik. ^ int.a.3 D 21 Ρ 1/02 SUOM I —Fl N LAN D (21) P »Mnttlh» k * mu * - PutunttntBknlng 801587 (22) H »k * m1spUvl — AmDkntnf * d« f 15 · 05 · 8θ (23) Atkupllvl - Glltigheodag 15.05.80 (41) Tullut fulktseksl - Bllvlt offuntilg 2.6.11.8l

Patmttl · and my registry * Ntht »vUc, iP» non |. month.un.un.un date—

Patent · och registerstyrelsen 7 Aiwtk * n utUgd och utijkrtften pubix®r * d 31.08.83 (32) (33) (31) Pietty etuoikeus — Begird prlorttet (71) Valmet Oy, Punanotkonkatu 2, 00130 Helsinki 13, Finland-Finland ( Fl) (72) Erkki Yli-Kokko, Jyväskylä, Finland-Finland (FI) (7 * +) Forssen & SaJLomaa Oy (5 ^) Paper machine multilayer headbox - Etageinloppsläda för pappersmaskin

The invention relates to a multilayer headbox of a paper machine having two or more overlapping flow channels of pulp suspension which coincide in the region of the lip gap of the headbox, the flow channels comprising a manifold part, a manifold part or the like and a flow equalizing and turbulent part and a lip part there is a plate portion supporting the headbox structure provided with flow orifice sets, said turbulence portion being formed of a plurality of parallel plate lamellae or the like.

The object of the present invention is to further develop the headbox with a lamellar part disclosed in the applicant's FI patent No. 50 260 so as to provide an advantageous slit layer box.

Multilayer headboxes are used in paper machines, especially when the pulp web is formed from two or more pulp grades which are passed along several overlapping flow paths to a forming wire or forming roll. In some cases, it may be advantageous to use a multilayer headbox even when only one pulp grade is used, but from the point of view of forming the web base.

__ - I

2,646? 3 achieves certain advantages when using two or more overlapping mass flow channels in a headbox.

With regard to the state of the art related to the present invention, reference is made to U.S. Patents 1,909,150, 3,216,892, 3,351,522, 3,573,160, 3,598,696 and 3,923,593, as well as the aforementioned Applicant's FI Patent No. 50,260 (e.g. U.S. Pat. Patent No. 3,791,198).

0

In order to achieve the above and later objects, the invention is mainly characterized in that said plate lamellas are fixed in place at their front end to said plate part and that there are one or more spacers between the sets of plate lamellae extending into the lip portion of the headbox.

In practice, the invention offers several significant advantages, the most important of which is that the headbox according to the invention can be easily converted into two or more layers and that the lamellae can be made relatively light, e.g. of acid-resistant steel or plastic, because the lamellae are not actually load-bearing parts. Another advantage is that a relatively simple and inexpensive structure is obtained, in the operation of which the advantages presented in the applicant's above-mentioned FI patent no. 50 260 are realized.

The invention will now be described in detail with reference to an embodiment of the invention shown in the figures of the accompanying drawing, to which the invention is not limited.

Figure 1 shows a machine direction vertical section of a headbox according to the invention.

Figure 2 shows section II-II in Figure 1.

The figures show a three-layer headbox with three overlapping pulp feed channels from the manifold 10 to the lip slot 26 of the headbox, where the different channels merge. However, it must be stated at the outset that the headbox according to the invention can be implemented in two or more channels as required. In addition, different channels can be fed different or the same mass quality. In Fig. 1, reference numerals 40A, 40B, 40C schematically denote the pulp feeders 10 of the first manifold 10.

The manifold 10 is divided into three overlapping parts 10A, 10B, 10C. After the manifold 10 follows a manifold piping 11 with three overlapping parts 11A, 11B, 11C, respectively. The manifold piping 11 is followed by an intermediate frame with three layers 15A, 15B, 15C.

The headbox comprises a lower wall structure 12, 13 and 14, of which the lower lip beam 14 terminates in a lip gap 26. Respectively, the headbox comprises an upper wall structure 16, 17 and 18, the upper lip plate 18 being part of an upper lip beam 19 provided with a lip gap 26 fine adjustment device 20, 21 , 19 can be turned around its horizontal joint 29. The adjusting devices 22 are attached to the upper beams by means of flanges 23.

The intermediate chamber part 15 is delimited between the walls 12 and 16. The intermediate chamber 15 is followed by a grating plate 30 with a plurality of parallel and overlapping openings 35, the more detailed implementation of which will be described later. After the grate plate 30, a lamellar part 36 follows the mass-suspension flow path, which consists of three overlapping layers 36Λ.36Β and 36C, which abut the lower wall 13 and the upper wall 17 and the intermediate plates 33A and 33B between them. The baffles 33A and 33B extend from the lamella portion 36 to the lip cone portion 37 and terminate near the lip gap 26. The lip cone channels 37A, 37B and 37C abut between the spacer plates 33A and 33B and the lower lip wall 14 and the upper lip wall 18.

Thus, starting from the distribution support 10, three overlapping flow channels of the pulp suspension are formed, which merge in the region of the lip gap 26 of the headbox, from which the pulp is discharged, for example, onto a wire 28 passing over the roll 27.

According to Fig. 1, the headbox is supported from below its front part by articulated shafts 24 and from the lower part of its rear part by adjusting devices 25, which operate e.g. by helical gears, by means of which the position of the headbox Of course, the headbox may also include various sliding arrangements by means of which the headbox can be moved substantially horizontally.

According to the invention, the jam part 36 comprises two or more layers of adjacent lamellae 31A, 31B, 31C, which according to Fig. 2 are in an oblique position (angle α) with respect to the vertical plane. The magnitude of the angle α is preferably between 10 ° and 30 °.

64673

According to the invention, an essential part of the headbox structure is a grating plate 30, which is very strong so as to receive a substantial part of the loads on the headbox. The thickness a of the grate plate 30 is thus relatively large and the top wall beams of the headbox are attached to its upper part and the lower wall beams of the headbox to the lower part. In addition, according to the invention, lamellae 31 oblique to the vertical plane are attached to the grating plate at point 32. The lamellae 31 are unattached at their front in the flow direction of the pulp suspension. The lamellae 31 also do not act as load-bearing structural elements of the headbox, but there are relatively narrow vertical slots Δ between them and the walls 13 and 17 and the spacers 33A and 33B. The size of the cracks Δ is such that no fibers accumulate in them. The lamellae 31 are substantially rigid in structure, although they do not participate in carrying loads. The spacers 33A and 33B are also relatively rigid so that the gaps between them and the lamellae 31 remain substantially constant. The spacers 33A and 33B are attached to the side walls of the headbox at their edges, if necessary. This attachment is not always necessary.

Between the oblique lamellae 31, the grate plate 30 has obliquely flow openings 35 in a manner corresponding to the oblique of the lamellae 31. Between the upper and lower edges of the openings 35 and the partitions 33A and 33B there is a small distance substantially equal to said distance Δ.

In the operation of the structure described above, and in particular in the operation of the plate part 30, it is essential that the plate part is made so strong that the pressure loads on the lip part 37, the lamella part 36 and partly also on the intermediate chamber part 15 pass through the plate part 30. Thus, the plate part 30 is subjected to vertical drawing and the manifold part 11 is pressed.

The lamellae 31 can be made relatively light, e.g. made of acid-resistant steel or a suitable plastic material. However, the lamellae 31 are relatively rigid and are not actually flexible and change position and shape with the flow, as is the case with some prior art structures.

The following are claims within the scope of which the various details of the invention may vary within the scope of the inventive idea.

Il

Claims (8)

A floor inlet carriage of a paper machine having two or more pulp suspension flow channels superposed in the region of the inlet drawer lip gap (26), and which flow channels comprise a distribution stock portion (10), a distribution pipe portion ( a smoothing and turbulence part (15,36) for the flow and a lip part (37), wherein between the equalizing part (15) and the turbulence part for the flow there is provided an inlet slab structure (30), which is provided with series (35) of flow openings, wherein said turbulence part (15) is formed by several parallel disc slats (31) or the like, characterized in that said disc slats (31) are fixed in place at their front end at said disc part (30) and that one or more intermediate discs (33A) , 33B) are arranged between the series (31) of disc slats extending to the region of the lip portion (37) of the inlet drawer. 2. An inlet drawer according to claim 1, characterized in that said disc slats (31) are spaced apart at a certain small distance (Δ) from a lower wall (13) in the slab part, an upper wall (17) and the intermediate disc (s) (33A, 33B) and that the front ends of the slats (31) are without bracket. An inlet drawer according to claim 1 or 2, characterized in that the disc slats (31) are flat and extend substantially to the beginning of the lip part (37). An inlet drawer according to claim 1,2 or 3, characterized in that the disc slats (31) start in an oblique position (winkin a) in the vertical plane. An inlet drawer according to claim 1,2,3 or 4, characterized in that said intermediate disc (s) (33A.33B) extend in the spaces of the slat series (31A, 31B, 3IC) separated at a small distance from these to the lip part. (37), in which the intermediate disc or intermediate discs (33A.33B) limit two or more overflow channels (37A, 37B, 37C) which are joined in the region of the lip of the inlet carriage (26). An inlet drawer according to claim 1,2,3,4 or 5, characterized in that said disc part (30) has the same number of opening series (35) above