SU1263737A1 - Head of paper-making machine - Google Patents

Abstract

This invention relates to a paper machine design and can be used in pulp and paper industry. The purpose of the invention is to improve the quality of the cast sheet due to the intensification of mass dispersion. The pressure box includes a housing 1 with an inlet device 2. A perforated plate 4 of the flow distributor 3 is installed across the mass direction in the housing 1. The perforated plate 4 is equipped with a vibration actuator 11, which, under the action of pushers 10, provides the reciprocating movement in the direction of mass movement and a spring 12 to return the plate 4 to its original position. The holes 5 of the plate 4 have a conical longitudinal section, tapering in the direction of the mass movement. Thanks to this, with symmetric oscillations (L of the narrow-output PDS of the openings 5, submerged turbulent jets are ejected, which provide active dispersion, disorientation of the fiber relative to the flow axis, mixing of the fibers and prevention of clogging of the holes in clots. 2 Il.

Description

This invention relates to a paper machine design and can be applied in the pulp and paper industry.

The purpose of the invention is to improve the quality of the cast sheet due to the intensification of mass dispersion.

The execution of the holes of the plate with a conical longitudinal section and its reciprocating movement reduces the hydrodynamic resistance of the mass flow when passing through it. Thus, submerged turbulent jets are formed at the exit from the holes, promoting active dispersion of fibers in the flow volume both at the exit from the holes and away from the plate, which leads to an improvement in the flow structure and, consequently, to an increase in the quality of the cast sheet.

FIG. 1. Shows the pressure box side view; in fig. 2 shows section A-A in FIG. one.

The discharge valve comprises a housing 1, an inlet device 2, and a rectangular cross-section flow distributor 3, one of the vertical walls of which is designed as installed in the housing 1 across the mass direction of the plate 4 with openings 5 having a conical longitudinal section. Plate 4 has guides 6, which enter the grooves 7 of the upper 8 and lower 9 horizontal walls of the distributor 3. The pushers 10 connected to the plate 4j are connected to an electromagnetic vibratory actuator 1, the spring 12 is intended to return the plate 4 to its original position. The holes 5 are tapered in the direction of the mass movement.

The paper pulp is fed into the flow distributor 3, distributed over the entire width of the plate 4 and through the holes 5 penetrates into the case 1 of the headbox. Simultaneously with the feeding of paper pulp into the pressure box, a voltage is applied to the electromagnetic coils of the vibrating actuator 11, the plate 4 under the action of the pushers 10 makes a reciprocating movement in the guides 6 placed in the slots 7. The holes 5 have a great resistance to penetration of the paper pulp in the direction of expansion , bw; m in the direction of constriction. Thanks

With symmetrical vibrations of the plate 4, flooded turbulent jets are pulled out of the narrow exit of the holes 5, which provide active dispersion, disorientation of the fibers relative to the flow axis and mixing of the fibers in the flow volume both at the exit from the holes 5 of the plate A and when moving away from the plate 4, they prevent clogging of the holes by 5 clots of mass passing through the mass pipeline to the pressure box, which contributes to the improvement of the structure of the flow of paper pulp fed to the inlet 2. The amplitude and frequency of the longitudinal to The scale and intensity of the generated turbulence are determined by the plate oscillations 4. The choice of the optimal frequencies and amplitudes of plate 4 oscillations is carried out separately for each type, paper pulp, its composition, concentration and speed of the passing stream. Adjusting the frequency and amplitude of the vibrating cable I1 is done by changing the value; magnetizing current in electromagnetic coils.

The use of the invention allows to significantly improve the quality of the cast sheet due to the active dispersion of the fibers of the paper pulp in the cavity of the headbox, as well as preventing clogging of the plate holes. At the same time, changing the frequency

5 and the amplitude of the plate oscillations,

the degree of dispersion can be adjusted depending on the type of paper pulp and its concentration, thus improving the flow structure

0 paper pulp fed into the zone of the inlet device, and improving the quality of the finished product

Claims (1)

Invention Formula A press box holder for a paper machine, comprising a housing, an inlet device and a perforated flow distributor plate installed 0 in the body across the direction of movement of the fibrous mass, about t and h and th and so that, in order to improve the quality of the cast sheet due to the intensification of dispersion 5, the perforated plate is installed with the possibility of reciprocal movement in the direction of the movement of the mass and is equipped with vibra312637374 The actuator, and the plate openings have a zhaklcees in the direction of movement, a masconic longitudinal section, su-; sy. 4 s eight / FI.2