SU1236036A1 - Forming apparatus for paper-making machine - Google Patents

Description

The invention relates to a device for the inlet of pulp on the forming grid of a paper machine and can be used in the pulp and paper industry.

The purpose of the invention is to determine the quality of the cast sheet by generating high-speed jets at the outflow from the feed pipes.

FIG. 1 shows a device, a cross section; in fig. 2 - section AA in FIG. 1; in fig. 3 is a view B in FIG. 2; in fig. 4 - installation of pipes for supplying gaseous medium on the device.

The device comprises a means for dispersing a mass consisting of a collector 1 for supplying a high concentration of mass connected to it by a curvilinear pipe 2, in which there is a sleeve 3 with a drive 4 for rotating the self-centering spiral tape 5. outlets that are flattened vertically. The device has a means for dispersing a high concentration mass, made in the form of nozzles 7, covering the inlet nozzles 6. Nozzles 7 are connected to collectors 8 for supplying a low concentration mass. The device has a housing 9 connected to a rotating chamber 10, which is provided with a shock surface 11 passing into exhaust channels 12. In addition, the device can be equipped with nozzles 13 for supplying a gaseous medium installed on the side walls of the housing mass of low concentration.

The device works in the following way.

A concentrated pulp with a concentration of 1.5% through a curved pipe 2 enters the collector 1, where under the action of a fungal tape 5 that creates high velocity gradients rotating with the aid of a sleeve 3, the mass is pre-dispersed, as a result of which its viscosity decreases. At the same time, the tape 5, due to the considerable average viscosity of the mass, is self-centered during rotation and does not touch the walls of the collector 2. Then the mass is distributed along the flattened out branch pipes 6, At 360362

than due to reduced viscosity in the zone of entry to the nozzle and additional radial force arising during the rotation of the spiral, the mass flows in

5 in the connections with a significant speed. A dilute suspension is supplied at a concentration of, for example, 0.4% through the collectors 8, which is distributed through the nozzles 7, where, due to its low bone size and small cross-section, the nozzles acquire a high flow rate. The obtok edges flattened nozzles 6 high-speed jets diluted suspension capture

15, for its part, a stream of KqH-centered mass exiting from nozzles 6 and gives it a high speed. At the same time, in the outlet sections of the nozzles 6, a rarefaction is created: Zoogenic, which provides a free passage of highly concentrated mass through them. The high-speed jets of the mixture of the concentrated and diluted suspension collide with each other and

25, over a short period of time, they hit the impact 1 of the turning chamber 1 1. At the same time, the elementary volumes of the fibrous mass belonging to different jets are tested

30 double force action, following each other after a short period of time. Then the mass flow from the PTZ camera passes to the outlet 1, channel 12, where it is stabilized by -JJ P.TC5I, and enters the grid of the machine.

Due to the high mass flow rate in the flattened nozzles 6, achieved by the rotation of the helix 5, d, it can be more

The 40 times caused by the flow of a low concentration suspension through the nozzles 7 increase both the speed of the jets of mass on the impact surface 11 and the transition coefficient

43, the kinetic energy of the jets in the turbine is high, which allows for a high degree of dispersion of the mass flow in the inlet device, and thus, to achieve a good quality of the molded paper web.

50

To increase the degree of dispersion in the case of a working mass concentration of 4.5%, a gaseous medium is fed through the inlet pipes 13.

55 As a result of the dilution created in the exit section of the nozzles, gas bubbles increase in mass jets. When: braking of the jets on the shock po31

surface 1 I occurs a sharp increase in pressure, as a result of which gas cavities collapse, forming cavitation impulse streams that enhance the dispersion effect.

Example. Cardboard is formed from pulp consisting of 23% wood pulp and pulp of bleached pulp in quantity Cardboard indicators

Known 268 Suggested

266

From the above example, it is clear that the physical-mechanical increase in the proposed device of the technical characteristics of the technical filter is compared with the well-known large-sized card.

/ dl /

364

Be 77%. Baseline Concentration

3.8%, diluted suspension concentration 0.4%. The mass concentration exiting to the grid part is 2.1%.

The table shows the physicomechanical characteristics of the technical filter paper weighing 270 g / m, obtained using a known device on a weight of 1% and the proposed device.

99

55

862

114

62

860

FIG. g

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Fig.Z

Editor N. Dankulich

Compiled by Y. Clin

Tehred I.Popovich, Proofreader V. But ha

Order 3069/29 Circulation 355 Subscription

UPIPN State Committee of the USSR

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company, Uzhgorod, st. Project, 4

FIG.

Claims (2)

1. PAPER MACHINE START-UP DEVICE, comprising a collector for supplying high concentration pulp, a housing connected to it with a rotary chamber, inlet pipes, the outlet openings of which are tapered vertically, and an exhaust channel, which means that with the aim of improving the quality of the molded web by creating high-speed jets when flowing out of the supply pipes, it has a low concentration mass distributor and means for dispersing a high concentration mass, aspredelitel weight of a low concentration has a nozzle encompassing lead-in tubes, and means for dispersing the mass is in the form of nozzles extending along .kollektora self-centering of the spiral belt drive. _β 2. The device according to π. I, Otl and - (g characterized in that it has nozzles for supplying a gaseous medium installed in the side walls of the housing at the level of the outlet openings of the nozzles for supplying a low concentration mass. Figure 1 1 1236036 2