SU1258920A1 - Method of dehydrating paper web - Google Patents

Description

one

This invention relates to a process for dewatering a web in a grid portion of a papermaking machine and can be used in the paper industry.

The purpose of the invention is to intensify the process of dehydration,

The drawing shows the dewatering scheme in the grid part on one of the register rollers,

The water-saturated mass of the grid 1 is fed at a speed / into the zone of contact with the register roller 2, rotating at an angular velocity UJ, which informs the points of the roller surface the circumferential speed

,

where g is the outer radius of the roller,

As a result of the dewatering effect, a wedge water grip is formed at the exit of the net from contact with the roller.

In the known method, the rotation of the register rollers 2 is imparted by the frictional force that occurs when they contact the moving grid 1. The rotating speed of the roller V in this case is less than the speed of movement, the grid V due to the slip of the latter in the contact zone. The water in the wedge grip is distributed so that the direction of its average velocity vector V is determined by the direction of the velocity vector of the grid V to a greater extent. Due to this, there is a throwing of the liquid to the next along the grid

Compiled 10, Cl. Pin.

Editor A, Kozoriz Tehred I., Popovich Proofreader C, Shekmar

Z.Akz 5093/29 Circulation 355Subscription

VNIIPI USSR State Committee

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

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

register roller. The maximum intensity of suction of the liquid on the register roller P and the amount of water removed W are determined by the formulas and are characterized by the circumferential speed of the register roller V:

.,. W- -,

where S is the density of water;

V is the speed of the roller;

Mr. Radius Roller;

R is the resistance to dehydration;

b is the length of the working part of the roller.

A positive effect in the proposed method appears due to the rotation of the register roller with a peripheral speed V greater than the velocity of the grid V V (,. In this case, the vector of average water velocity

in the wedge grip, it rotates clockwise relative to the VQ vector and water from the wedge grip is removed into the space between the rollers. Following the specified formulas with

circumferential velocity, 3V suction intensity P increases by 1.7 times, and the amount of water removed W - 2.2 times. At a speed of 1.1V, these effects will manifest

not fully, and with V.1,5V the intensity of suction will be too high, which will lead to a violation of the structure of the dehydrated mass.

Claims (1)

METHOD FOR PAPER DRAINAGE DRAINAGE by admitting the mass onto a moving mesh of a paper machine and suctioning water by register rolls rotating in the direction of the grid movement, characterized in that, in order to intensify the dewatering process, the register rolls rotate at a peripheral speed exceeding the mesh speed of 1.1- 1.5 times. V at