SU956674A1 - Pressure box of paper-making machine - Google Patents

Description

The invention relates to the pulp and paper industry, namely to the pressure boxes of paper machines.

A pressure box is known that improves the uniform distribution of fibers in the flow structure of a fiber suspension by organizing microturbulence vortices with rod-turbulators installed in the area of the pressure box immediately preceding the inlet of the mass on the grid table 1,

However, the known pressure box does not provide the required degree of microturbulence in the zone where rapid dehydration and formation of the paper web structure occurs, i.e. on the net table. In addition, the flow structure of the fibrous suspension supplied from the headbox when interacting with the structural elements of the grid table undergoes significant changes due to such phenomena as web anisotropy, repeated flocculation, formation of cross jets, etc., which degrade the structure

molded canvas, and hence the quality of the paper.

The closest technical solution is a pressure box containing 1 orpus and an inlet device, the upper lip of which is installed above the net inclined to it. Some uniform distribution of the fibers is achieved by partially eroding the structure of the paper adjacent to the grid when it runs onto the openings of the covers of the suction boxes located under the grid in the forming zone of the web 2.

The use of a machine stretched along the mesh and the flat upper lip adjoining it does not provide the required dispersing effect on the fiber suspension that is in the dehydration and shaping zone, does not allow to control the degree of dispersion of the fiber suspension, and consequently, to improve the quality of the produced product 25 of

The purpose of the invention is to improve the quality of the cast sheet.

The goal is achieved by the fact that the pressure box of the paper machine, comprising a housing and

The inlet device, the upper lip of which is installed above the mesh obliquely towards it, has turbulence rods mounted across the direction of movement of the mesh under the upper lip parallel to its surface. The turbulence rods have a cross-section of ellipsoidal shape and means for turning around their longitudinal axis.

In addition, turbulence rods are installed at different heights with respect to the grid.

La figure 1 shows the discharge box side view; figure 2 - section aa in figure 1.

The headbox of the pulp web machine comprises a body 1 having a mass supply 2. The body 1 is provided with an inlet device with an upper lip 3 extending along the machine grid and forming an upper lip forming zone 5 with the lower lip. 5, rotor turbulators 6 are installed, which may have an ellipsal-shaped cross section that can be rotated around its axis and displaceable one relative to the other in height. Rods turbulizer 6 is fixed in the side walls 7 of the inlet device with nuts 8. The grid 9 is located above the water-permeable lids 10 connected to the suction pins 11.

Headbox works as follows.

When the machine is in operation, the fiber suspension flows from the case 1 of the pressure box to the forming zone of the web 5 formed by the lip 3 and the lower lip adjacent to it and the lower lip 4. The mass flows, flowing around the surface of the turbulence rods 6, form microturbulence vortices that the pulp is dispersed in the zone of dewatering and shaping the web, thereby contributing to a uniform distribution of the fibers in the structure of the molded paper web, improving the lumen, as well as improving the dewatering regime and suction schikah. The reduction of hydrodynamic resistance in the zone of forming the web 5 and the decrease in the mass of turbulence is due to the fact that the bifurcate holders are made with an ellipsoidal cross-section with the possibility of rotation around its axis. Increased turbulence in the web forming zone 5

is carried out by shifting the rods of the turbulence in height or by changing their geometrical parameters.

For each bladder mass with its

The working concentration, composition and degree of grinding require a certain range of microturbulence in the zone of dewatering and shaping the paper pulp, which ensures its most effective dispersion.

Therefore, the intensity and scale of the generated micro-turbulence depends on the geometrical parameters

turbulators rods b and their placement in the zone of dewatering and forming paper mass.

The use of the invention significantly improves the quality

casting cloth due to intensive deflocculation of paper pulp in the dewatering and molding zone, effectively manage the degree of dispersion depending on the modes

The casting of one or another type of paper pulp, which achieves the optimal mode of dewatering and shaping of paper pulp, which allows to obtain high quality paper with a uniform distribution of the mass of 1 m - an important indicator in the production of paper.

Claims (4)

1. A backing box of a paper machine, comprising a housing and an inlet device, the upper lip of which is installed above a grid of donut knots, characterized by a hem that, in order to improve the quality of the molded web, it has turbulence rods installed transverse to the direction of movement 5 grids under the upper lip parallel to the surface. 2. Box POP.1, which is different with the fact that the rods-turbulators have a cross-section of ellipsoidal shape. 3. Box of PP. 1 and 2, which is based on the fact that the wall turbidators have means for turning around their longitudinal axis. 4. Box of PP. 1.2 and 3, characterized in that the tubular urinators are installed at different heights with respect to the grid. Sources of information taken into account in the examination 0 1. USSR author's certificate 452642, cl. D 21 F 1/02, 1967. 2. USSR author's certificate number 375857, cl. D 21 F 1/02, 1964 (prototype). Yu Yu ZhOZH 1VN YAI | 11 "gP% I 9.PIi {1 | 19.y" P "N 9110PIP 119N gP gKZHZH" UZH vk HHHHH // - // fff ff / FIG. I