CN103821023A

CN103821023A - Complementary headbox

Info

Publication number: CN103821023A
Application number: CN201410072214.XA
Authority: CN
Inventors: 刘伟; 冀晓辉; 宣征南
Original assignee: Guangdong University of Petrochemical Technology
Current assignee: Guangdong University of Petrochemical Technology
Priority date: 2014-03-03
Filing date: 2014-03-03
Publication date: 2014-05-28

Abstract

The invention discloses a complementary headbox. Two square-taper pulp distribution header pipes (1 and 5) which are the same in structure are vertically stacked together, are eudipleural and are not communicated with each other; outlets at corresponding positions of the two square-taper pulp distribution header pipes are respectively connected with corresponding small mixing chambers (3) in a dividing wall type mixing chamber through a first group of branch pipes (2); the outlet of each small mixing chamber is connected with a plenum chamber (4) through a second group of branch pipes (4). According to the complementary headbox disclosed by the invention, the two square-taper pulp distribution header pipes which are the same in structure are adopted to replace a unidirectional pulp feed-in square-taper pulp distribution header pipe, so that pulp distribution characteristic curves of the two square-taper pulp distribution header pipes are equally distributed after being reversely superposed to implement complementary pulp distribution; in order to guarantee a mixing effect of the complementary pulp distribution, the dividing wall type mixing chamber is adopted, so that each small mixing chamber is only capable of completing the pulp mixing of a group of corresponding branch pipes, and the complementary mixing of high flow and small flow is realized; mutual interference between jet flows of horizontal branch pipes is eliminated; after being mixed, the jet flows of any group of corresponding branch pipes of the two square-taper pulp distribution header pipes are independently mixed and averaged in single mixing chambers of a multi-cavity mixing chamber, and further, the pulp distribution uniformity is guaranteed; the mass flow rate of the branch pipe of the outlet of each small mixing chamber is much closer to a desired value.

Description

A kind of complementary pulp distributor

Technical field

The present invention relates to the pulp distributor technical field of hydraulic headbox, specifically a kind of complementary pulp distributor with dividing wall type mixing chamber.

Background technology

In the evolution of head box, adopted once expanded channel formula cloth paste-making method, multiple separable type cloth paste-making method, centre to enter to starch branched tubular type cloth paste-making method, cross-current type cloth paste-making method etc., but drawback because overcoming separately does not re-use.In 20 end of the centurys, head box has adopted the unidirectional method of entering to starch and passing through to prop up tube bank cloth slurry of square Taper Pipe substantially.Because the rear wall of quadrate centrum main pipe is complex-shaped, the house stewards that adopt straight line reduced form or piecewise approximation type while use in engineering more, therefore, distribute and bring certain transverse pressure difference to slurry, the uniformity that has affected headbox stock whitewashing online, along with the raising of the speed of a motor vehicle, this species diversity is more obvious.Along with the application of cylindrical shape pulp distributor, there is again a kind of new cloth paste-making method, rely on stable liquid level to take the mode of circumferential cloth slurry, guarantee the uniformity of cloth slurry.Although circumferentially the cloth of cloth paste-making method slurry performance is significantly improved, cloth slurry position is more concentrated, and therefore applicable fabric width is difficult to meet the requirement day by day improving.Modern high-speed paper machine adopts individual event to enter the quadrate centrum main pipe pulp distributor of slurry substantially, due to the raising of the speed of a motor vehicle and the increase of fabric width, cause also can increasing along the slurry pressure difference of quadrate centrum main pipe direction, for guaranteeing that slurry is evenly distributed, adopted complicated dilution water regulating system., domesticly there is complementary cloth paste-making method in this year, this method is starched inhomogeneous characteristic based on step diffuser headbox cloth and designed, and has proposed concept and the structure of complementary pulp distributor.The slurry going out from step diffuser headbox arm line directly enters mixing chamber, and each strand of slurry stream here mixes.The effect of mixing chamber is exactly to make slurry stream can reach uniform state before outflow mixing chamber.Due to the mutual interference effect of jet, in mixing chamber, easily there is the phenomenon that athwartship leg jet is assembled, cause slurry to distribute and concentrate to centre, affect being uniformly distributed of slurry.

Summary of the invention

The object of this invention is to provide on a kind of basis of starching at complementary cloth, a kind of mutual interference effect of avoiding between athwartship leg jet is provided, guarantee mutual interference and complementary blending effect between corresponding arm, realize pulp distributor slurry and be evenly distributed.

The complementary pulp distributor of one provided by the invention, two identical square cone slurry-distribution house stewards of structure are stacked together up and down, symmetrical, not connected, the outlet of two square cone slurry-distribution house steward correspondence positions connects corresponding little mixing chamber in dividing wall type mixing chamber by first group of arm respectively, and the outlet of each little mixing chamber is connected with plenum chamber by second group of arm respectively.

As to further improvement of the present invention, the structure of every arm in first group of arm is identical, in the same size; The structure of every arm in second group of arm is identical, in the same size; The inner chamber size of the little mixing chamber in dividing wall type mixing chamber is identical.

The present invention compared with prior art, tool has the following advantages: adopt two square cone slurry-distribution house stewards that structure is identical, replace a unidirectional square cone slurry-distribution house steward who enters to starch, make after the reverse stack of cloth slurry performance curve of two quadrate centrum main pipes, mean allocation again, implements complementary cloth slurry; For guaranteeing the mixed effect of complementary cloth slurry, adopt dividing wall type mixing chamber, the slurry that makes each little mixing chamber can only complete one group of corresponding arm mixes, having realized large flow mixes with the complementation of low discharge, and get rid of horizontally-arranged and propped up the mutual interference between pipe jet, after mixing, the jet that guarantees any one group of corresponding arm of two quadrate centrum main pipes carries out independence mixing and average in the independent mixing chamber of multi-cavity type mixing chamber, further guarantee cloth slurry uniformity, each little mixing chamber outlet arm mass flow more approaches desired value.

Accompanying drawing explanation

Fig. 1 is structure principle chart of the present invention.

Fig. 2 is the mixed mass flow distribution figure of dividing wall type mixing chamber.

Fig. 3 is that the mixing of dividing wall type mixing chamber retrodeviates difference Butut.

The specific embodiment

With reference to Fig. 1, the complementary pulp distributor of one provided by the invention, two square cone slurry-distribution house stewards (1 that structure is identical, 5) be stacked together up and down, symmetrical, not connected, two square cone slurry-distribution house stewards (1, 5) outlet of correspondence position connects corresponding little mixing chamber 3 in dividing wall type mixing chamber by first group of arm 2 respectively, the outlet of each little mixing chamber 3 is connected with plenum chamber by second group of arm 4 respectively, the structure of every arm in first group of arm 2 is identical, in the same size, every arm in second group of arm 4 is also that structure is identical, in the same size, the inner chamber size of the little mixing chamber 3 in dividing wall type mixing chamber is identical.Arm quantity in first group of arm 2 and second group of arm is determined as required.

When installation, first square cone slurry-distribution house steward 1 and square cone slurry-distribution house steward 5 are stacked together up and down, symmetrical, not connected, be arranged on the porch of head box, be connected with little mixing chamber 3 by first group of arm 2, second group of arm number is identical with two the corresponding arm group of quadrate centrum main pipe numbers, each little mixing chamber 3 is separate, is independent of each other.Because dividing wall type mixing chamber is divided into some cavitys according to every group of corresponding arm by mixing chamber, make to only have one group of correspondence to prop up pipe jet in each mixing chamber, what in each mixing chamber, complete is the complementation mixing between corresponding arm purely, its mass flow distribution curve approaches desired value 2.955kg/s the most, arm mass flow maximum is 2.9599kg/s, minimum of a value is 2.9475kg/s, as shown in Figure 2.The mixed better effects if of dividing wall type mixing chamber, deviation is lower, and maximum positively biased difference drops to 0.166%, and maximum negative bias difference drops to-0.254%, and whole aberration curve trend and 0 value line are the most approaching, as shown in Figure 3.

Operation principle of the present invention is as follows: the slurry of equivalent flows to respectively two quadrate centrum main pipes (1, 5), except quantity of reflux, all the other flows are flowed out by first group of arm 2 of two quadrate centrum main pipes, enter the little mixing chamber 3 in dividing wall type mixing chamber, because the each little mixing chamber 3 of dividing wall type mixing chamber only completes one group of corresponding mixed function of propping up pipe jet, therefore, can effectively guarantee the complementary blending of a corresponding pipe jet, and be not subject to the impact of other pipe jet, the slurry stream that complete complementary mixes props up tube bank 4 by mixing chamber outlet again and enters plenum chamber, flow into lip contraction section, whitewashing online.

Claims

1. a complementary pulp distributor, it is characterized in that, two identical square cone slurry-distribution house stewards (1,5) of structure are stacked together up and down, symmetrical, not connected, the outlet of two square cone slurry-distribution house stewards (1,5) correspondence position connects corresponding little mixing chamber (3) in dividing wall type mixing chamber by first group of arm (2) respectively, and the outlet of each little mixing chamber (3) is connected with plenum chamber by second group of arm (4) respectively.

2. the complementary pulp distributor of one according to claim 1, is characterized in that, the structure of every arm in first group of arm (2) is identical, in the same size.

3. the complementary pulp distributor of one according to claim 1, is characterized in that, the structure of every arm in second group of arm (4) is identical, in the same size.

4. the complementary pulp distributor of one according to claim 1, is characterized in that, the inner chamber size of the little mixing chamber (3) in dividing wall type mixing chamber is identical.