13.2 双辊压榨在线视频

大家好，这节课继续介绍
Hello everyone, this lesson continues to introduce

造纸机压榨装置的第二节
the second section of the paper machinery press device

双辊压榨
i.e., the double-roll press

在这一节中，我们将逐一介绍
In this section, we will introduce

各种形式的双辊压榨装置
a variety of forms of double-roll press one by one

双辊压榨是由上、下两根压榨辊
Double-roll press is a press form which consists of

组成一个压区的压榨形式
the upper and lower press rolls to form a press area

也是最基本的一种压榨形式
and it is also the most basic press form

广泛应用于低速纸机
It is widely used in the press part of low speed paper machinery

和现代化高速纸机的压榨部
and modern high speeds paper machinery

除了双辊压榨
In addition to double-roll press

由多辊组成的复式压榨
the composite press composed of multiple rolls

也是以双辊压榨为基础发展起来的
is also developed on the basis of double-roll press

由于压榨辊的结构有多种
Because there are many structures of press rolls

双辊压榨也就有多种不同的形式
there are many different forms of double-roll presses

包括普通压榨、真空压榨、沟纹压榨
including common press, vacuum press, groove press,

盲孔压榨、平滑压榨、大辊径压榨
blind hole press, smooth press, big roll press

靴式压榨、托辊压榨等等
shoe press, touch roll press, etc.

这些都是应用较多的压榨形式
which are widely used

首先看普通压榨
First, let’s look at the common press

也叫平辊压榨
also known as flat roll press

先看一下其结构组成
Let's take a look at the structure

平辊压榨由上辊和下辊组成
Flat roll press is composed of upper roll and lower roll

一般上辊为从动辊
Generally, the upper roll is driven roll

采用花岗岩石辊或者人造石辊
the granite roll or artificial stone roll is used

下辊为主动辊
the lower roll is drive roll, mostly using rubber roll

多采用包胶辊

通常是空心铸铁辊辊体
usually hollow cast iron roll body

表面包橡胶或者聚氨酯
the surface is covered with rubber or polyurethane

其中，包胶的作用在于
Among them, the role of rubber coating is to

使辊面具有弹性
make the roll surface elastic

可以缓冲上辊的压力
can buffer the pressure of the upper roll

减少压溃
reduce crushing

减轻毛毯对湿纸幅的印痕
reduce the impression of the felt on the wet web

延长毛毯的使用寿命等
and extend the service life of the felt and so on

在一定程度上补偿中高的误差
To a certain extent, it can compensate the crown error

使两辊接触较好
make the two rolls contact well

脱水均匀
and dewatering evenly

普通压榨还可以再分为
Common press can also be divided into

正压榨和反压榨
positive press and reverse press

正压榨指的是
The positive press refers to the contact between

湿纸幅正面与上辊
the front side of the wet web and the upper roll

也就是石辊接触
that is, the stone roll

提高正面平滑度
which improves the front smoothness

反压榨指的是
the reverse press refers to the contact

湿纸幅反面也就是网面
between the back side of the wet web, i.e. the net side

与上辊也就是石辊接触
and the upper roll, i.e. the stone roll

可以提高反面平滑度
which can improve the reverse smoothness

减轻网痕
reduce the net mark

减小两面差
and reduce the difference between the two sides

那么平辊压榨过程中
So how is the moisture removed

水分是怎样脱除的呢
during the process of flat roll press

我们看一下平辊压榨脱水原理
Let's look at the principle of flat roll press dewatering

当纸页和毛毯到达压区中央的过程中
As the sheets and felts reach the center of the press area

纸页和毛毯逐渐受到压缩
the sheets and felts are gradually compressed

水从饱和的纸页中排出
and moisture is drained from the saturated sheets

并进入毛毯
and into the felts

当被挤压出来的水量
When the amount of moisture squeezed out

超过毛毯所能容纳的水量时
exceeds the moisture amount that the felt can hold

也就是说毛毯已饱和时
that is, when the felt is saturated

多出的水分就会沿压区的水平反方向流动
the excess moisture will flow in the horizontal opposite direction of the press area

并透过毛毯聚积在压区之前而形成水层
and accumulate in front of the press area through the felt to form a water layer

随即沿着下压辊的表面流掉
which will then flow along the surface of the lower press roll

这就是普通平辊压榨脱水中的
This is the horizontal reverse dewatering mechanism

水平反向脱水机理
of common flat roll press dewatering

如果挤压出的水量过大
If the amount of water extruded is too large

或毛毯滤水性较差时
or if the water filtering property of the felt is poor

超过毛毯所能容纳和透过的水量时
when the amount of moisture that the felt can hold and penetrate

多出水量就会被迫向上通过毛毯和纸幅
more moisture will be forced to pass through the felt and the web upward

造成湿纸幅中产生较大的水力压差
resulting in a greater hydraulic pressure difference in the wet web

当水力压差超过湿纸幅强度
When the hydraulic pressure difference exceeds

所能承受的数值时
the value that the wet web strength can bear

湿纸幅的组织结构就会被冲散
the structure of the wet web will be washed away

而造成所谓“压溃”现象，即“压花”
resulting in the so-called "crush" phenomenon, i.e., "embossing"

普通压榨上辊并不是
The common press the upper roll is not

垂直的压在下辊的中心线上
vertically pressed on the center line of the lower roll

而是上辊稍微偏向进纸一侧
but the upper roll is slightly inclined to the feeding side

上下两个压辊中垂线之间有一定距离
There is a certain distance between the vertical lines of the upper and lower rolls

两辊中心线之间的距离
and the distance between the center lines of the two rolls

称为偏心距
is called the eccentric distance

在压区中央以后的区间上
In the area after the center of the press area

由于纸幅较毛毯的毛细管小很多
because the capillary tube of the paper web is much smaller than that of the felt

在毛细管的作用下
under the action of the capillary

毛毯中的一部分水分
one part of the moisture in the felt

又重新转移到纸幅当中
is transferred back into the web again

产生所谓的回湿作用
resulting in the so-called wet-back effect

所以，当车速较高
Therefore, when the speed is higher

压区较窄、浆料较粗时
the press area is narrower, the slurry is thicker

回湿作用就轻一些
and the wet-back effect is lighter

平辊压榨的主要缺点有
The main disadvantages of flat roll press are

水平排水距离长
long horizontal drainage distance

阻力大，脱水效率低等
large resistance and low dewatering efficiency

接下来我们看一下辊子的特点
Next let's take a look at the features of the rolls

由于上辊所用的花岗石的受拉
Due to the difference between the tensile and compressive

和受压的极限强度有很大的差别
ultimate strength of the granite used in the upper roll is very different

石辊通常采用预应力结构
and the stone roll usually adopts the pre-stressed structure

花岗石的辊体用分别是左右螺纹的螺母
The roll body of granite is tightly pressed on the steel mandrel with nuts

和垫圈紧压在钢制的芯轴上
and washers with left and right threads respectively

平辊压榨的下榨辊通常采用的是
The lower press roll of flat roll is usually

具有平滑面的铸铁包胶辊
a cast iron rubber covered roll with smooth surface

或称平胶辊
or flat rubber roll

平胶辊的辊面是一层具有适当厚度
The roll surface of flat rubber roll is a smooth rubber layer

和硬度的平滑的胶层
with proper thickness and hardness

辊面经过磨削而具有适当的中高度
and the roll surface has an appropriate crown after grinding

接下来我们看一下第二种
Next let's take a look at the characteristics of the second

常见的压榨方式——真空压榨的特点
common type of press——vacuum press

真空压榨辊的结构和真空伏辊类似
The structure of vacuum press roll is similar to that of vacuum couch roll

但是有几点不同
but there are several differences

真空压榨辊的真空室宽度要宽一些
The width of vacuum chamber of vacuum press roll is wider

通常为100~125mm
usually 100~125mm

真空压榨辊辊面小孔的直径较小
and the diameter of small hole on the surface of vacuum press roll is small

为4.5mm左右
about 4.5mm

辊面开孔率较低
The aperture ratio of roll surface is low

一般为15%~25%
generally 15%~25%

真空压榨辊辊筒表面需要包胶
The surface of the vacuum press roll needs to be coated with rubber

胶层厚度20~25mm
and the thickness of the rubber layer is 20~25mm

真空辊的壳体采用青铜
The shell of vacuum roll is made of bronze

或不锈钢材料经离心铸造而成
or stainless steel by centrifugal casting

湿纸幅在真空压榨中的
The dewatering process of wet web

脱水过程如图所示
in vacuum press is shown in the figure

当湿纸幅通过真空压榨的压区时
When the wet web passes through the press area of the vacuum press

由于纸幅被上辊紧紧压住
because the web is pressed tightly by the upper roll

真空抽吸力并不对纸幅直接发生作用
the vacuum suction force does not directly affect the web

湿纸幅仍是在压力作用下脱水的
and the wet web is still dewatering under the pressure

所以真空压榨的脱水动力
So, the dewatering power of the vacuum press is

和普通压榨是相同的
the same as that of the common press

也就是湿纸幅是在上压辊的
that is, the wet web is dewatered

压力作用下进行脱水的
under the pressure of the upper press roll

而真空抽吸力的主要作用是
The main function of vacuum suction is to

把压区前侧毛毯中的水分吸掉
absorb the moisture from the felt on the front side of the press area

以降低毛毯进入压区前的含水量
so as to reduce the moisture content of the felt before it enters the press area

并保持毛毯良好的滤水性
and maintain the good water filtration of the felt

当湿纸幅和毛毯通过压区时
When the wet web and felt pass through the press area

压榨出的水分能立即
the moisture from the press can be immediately

被毛毯吸收并透过毛毯
absorbed by the felt and passed through the felt

在经过很小距离（约1/2孔距）
After moving horizontally at a very small distance

的水平移动后
(about 1/2 hole distance)

便能垂直向下进入辊壳的小孔中
it can go vertically down into the small hole of the roll shell

其中一部分水分进入真空室排出
One part of the moisture is discharged into the vacuum chamber

还有一部分水分则留在孔中
and the other part is left in the hole

当小孔转离压区后
When the small hole turns away from the press area

在离心力的作用下
under the action of centrifugal force

小孔中的水分被抛出
the moisture in the small hole is thrown out

真空压榨上下辊安装
There is also a certain eccentricity in the installation

同样也有一定偏心距
of the upper and lower rolls of the vacuum press

不过是下辊偏向进纸一侧
but the lower roll is inclined to the feeding side

由此可以看出真空压榨的优点在于
It can be seen from this that the advantages of vacuum press are

脱出的水是垂直流动
the moisture flowing out is vertical

排水距离短
the drainage distance is short

水流阻力小
and the flow resistance is small

这样的话，毛毯不会被水饱和
In this way, the felt will not be saturated with moisture

减少了湿纸幅“压溃”的可能性
reducing the possibility of "crushing" the wet web

可以采用较高的线压力
The high line pressure can be used to

提高脱水效能
improve the dewatering efficiency

有利于造纸机车速的提高
and the speed of paper machinery can be improved

接下来介绍第三种压榨形式——沟纹压榨
Next, we introduce the third form of press——groove press

上压榨辊一般也是花岗石辊
The upper press roll is generally the granite roll

只是压榨下辊采用的是沟纹压榨辊
but the lower press roll is the groove press roll

沟纹压榨装置的布置形式与普通压榨相似
The layout of groove press is similar to that of common press

包括毛毯的运行方向
including the running direction of felt

上压榨辊的偏心距方向等都是一样的
and the eccentric distance direction of upper press roll

辊面有很细密的、环形或螺旋形的沟槽
The roll surface has a very fine, circular or spiral groove

这些沟槽为压区内被挤压出的水分
These grooves provide an outlet

提供了排泄的渠道
for the water squeezed out in the press area

沟槽使压区的下方
The grooves allow the lower part of the press area

与大气相通
to communicate with the atmosphere

压区内的水分可以沿着垂直的
and the moisture in the press area can enter the groove

或者近于垂直的方向穿过毛毯进入沟槽
through the felt along the vertical or near vertical direction

水分在毛毯内所需横向移动的距离
The horizontal movement of moisture in the felt

不大于沟纹间距离的一半
is not more than half of the distance between the grooves

流阻较小
and the flow resistance is small

使压区的排水有比较理想的条件
which makes the drainage of the press area more ideal

这是沟纹压榨具有较高脱水效能的主要原因
This is the main reason for the high dewatering efficiency of groove press

沟纹压榨时
In the process of groove press

水从纸页挤进毛毯
moisture is squeezed from the sheet into the felt

又从毛毯就近挤进沟纹
and it is squeezed into the nearby groove from the felt

纸页内液压的上升幅度就小
the hydraulic rise in the sheet is small

从而造成压溃的可能性减少了
thus reducing the possibility of crushing

与普通压榨相比
Compared with the common press

使用沟纹压榨
the use of groove press

在无压溃和压花的前提下
without crushing and embossing

可以提高压榨的线压力以脱除更多的水分
can increase the press line pressure to remove more moisture

而且设备投资及运行费用几乎没有增加
and the equipment investment and operating costs have hardly increased

与真空压榨相比
Compared with vacuum press

使用沟纹压榨没有产生孔痕的危险
there is no danger of pore mark when using the groove press

纸幅脱水均匀
the web is dewatered evenly

更重要的是设备投资
more importantly, the equipment investment

和运行费用可以大幅度降低
and operating costs can be greatly reduced

所以沟纹压榨是一种
Therefore, groove press is an economic

经济、方便、高效的压榨方式
convenient and efficient way of press

在各种造纸机上的应用都非常广泛
which is widely used in all kinds of paper machinery

并且可以用作压榨部的各道压榨
and can be used as each press of the press part

接下来要介绍一种
The next step is to introduce

非常重要的新型压榨形式
a very important new type of press

也就是宽压区压榨
that is, extended-nip press

或者称之为靴式压榨
or shoe press

20世纪80年代初推出了
In the early 1980s, the extended-nip press

宽压区压榨或者叫延时压榨
or delay press was introduced

也称为靴形压榨和靴式压榨
also known as shoe shape press and shoe press

这种宽压区压榨是
This extended-nip press changes the

将辊式压榨的瞬时动态线压性脱水
instantaneous dynamic line pressure dehydration of roll press

改变为静压下的长时间宽压区脱水
into a long time wide press area dewatering under static pressure

大多数高速纸机
In most high-speed paper machinery

压榨时间在3ms以下
the press time is less than 3ms

而辊式压榨压区所提供的
while the press time provided by the roll press area

压榨时间在0.5～20ms之间
is between 0.5 and 20ms

对于大多数纸种
For most types of paper

如果压榨时间能够大幅度增加
if the press time can be greatly increased

如增加5～10倍
such as 5~10 times

这样压榨冲量就可以增加5～10倍
so the press impulse can be increased 5~10 times

从而大大地提高纸幅压榨后的干度
so as to greatly increase the dryness of the paper after the press

为此出现了宽压区压榨
therefore, the extended-nip press appeared

即靴式压榨
that is, shoe press

这种压榨形式可以用于
This form of press can be used in

挂面纸板、强韧箱板纸和瓦楞纸
the production of high-quality paper such as

这些定量较高的纸种的生产
hanging board, tough box board and corrugated paper

现在也可以用于新闻纸
Now it can also be used in the production of newsprint

高级印刷纸等其他品种的生产
high-grade printing paper and other varieties

后来各供应商都开发了封闭式靴式压榨
Later, each supplier developed the closed shoe press

把靴式压板安装在
and installed the shoe press plate in the

旋转的有良好柔韧性的压榨套内
rotary press sleeve with good flexibility

形成一个具有特殊结构的压榨辊
forming a special structure of the press roll

即靴压辊
that is, the shoe press roll

其特点是简单、可靠
Its characteristics are simple and reliable

并且压区的压力分布曲线也是可调节的
and the pressure distribution curve of the press area is adjustable

从而得到了广泛的应用
so it has been widely used

图中就是采用了2组靴式压榨的压榨部
In the picture, two groups of shoe press in the press part are used

从这张压区宽度与压力的对照图中
From the comparison chart between the width and the pressure of the press area

可以看出，传统的辊压的压区宽度最小
it can be seen that the press area width of the traditional rolls is the smallest

大辊压的较之较多
the large diameter roll is larger

而宽压区的压区宽度最大
while the width of the extended-nip press is the largest

并且在其压区上面压力呈现
and the pressure above the press area shows a trend of

先急剧上升、再平缓上升
first sharp rise, then gentle rise

最后又急剧上升
then sharp rise

最终迅速下降的趋势
and finally rapid decline

针对宽压区压榨这种非常典型的压榨方式
For the extended-nip press, let’s take a look at the

我们看一下它的发展历程
development of this very typical press type

首先是早期的开放式宽压区压榨
The first is the early open extended-nip press

结构相对简单
which is relatively simple in structure

由一个可控中高沟纹辊作为上辊
It consists of one controllable crown groove roll as the upper roll

一条靴压板、一条橡胶衬带
one shoe press plate, one rubber lining belt

以及推动压板的液压装置等组成\ and a hydraulic device to push the press plate

压榨时纸页夹在两条毛毯之间
When pressing, the sheet is sandwiched between two felts

从压辊和压板
and passes through the press area formed by the

衬带构成的压区中通过
press roll, the press plate and the lining belt

经过改进后
After improvement

形成了这种密封性的结构
the sealing structure was formed

即新型密闭式的靴式压榨装置
i.e. a new type of closed shoe press device

由可控中高辊和靴形压榨辊组成的靴压形
It is composed of one controllable crown roll and one shoe press roll

比早期开放式要更为完善
which is more perfect than the early open type

就靴压辊靴压区上面的
According to the analysis of the line pressure distribution

线压分布进行分析
on the upper part of the shoe press area

可以看出，按照压力的分布
it can be seen that, according to the pressure distribution

分为三个特性区域
it is divided into three characteristic regions

在脱水前的第一区压力急剧上升
and the pressure in the first area increases sharply before dehydration

在脱水期间第二区
the pressure in the second area rises gradually

压力逐渐上升以保证均匀加压
during dewatering to ensure uniform pressure

在第三区压力急剧下降以防止回湿
and the pressure in the third area drops sharply to prevent wet-back

这种压力特性对平缓的脱水
This pressure characteristic is indispensable

和具有高松厚度的均匀纸幅结构
for smooth dewatering and

是不可缺少的
uniform web structure with high bulk

这是刚才展示的封闭的
This is a schematic diagram of the section structure

靴压结构的剖面结构示意图
of the closed shoe pressure structure just shown

可以看出，上面的可控中高辊
It can be seen that the upper controllable crown roll

是由多个加压元件组成
is composed of several press elements

压区加压通过液压系统
and the press area pressure is realized by

调整加压元件来实现
adjusting the press elements in the hydraulic system

目前较为成熟的靴压辊
At present, the more mature shoe rolls

基本上都是封闭式的
are basically closed

以福伊特的NipcoFlex靴形压榨辊为例
Taking the NipcoFlex shoe press roll of Voith as an example

可以看出其主要由
it can be seen that it is mainly composed of

加压靴板、加压组件、靴套
press shoe plate, pressurized components, shoe sleeve

导向杆及支撑梁等部分组成
guide rod and support beams

封闭结构，其中的支撑梁简称靴梁
Closed structure, in which the support beam is referred to as shoe beam

是静止的承重构件
is a static load-bearing member

形似工字钢结构，固定安装
similar to the I-beam structure, fixed installation

靴形压榨辊的靴板斜度
The slope of the shoe plate of the shoe press roll

可以通过靴板下面的加压组件进行调节
can be adjusted by the pressurized components under the shoe plate

靴板表面套是经过加强处理的
The shoe plate surface cover is a reinforced

合成纤维编织基网
synthetic fiber woven base mesh

我们称之为靴套
which we call the shoe cover

当前密封型的靴压辊
At present, the closed shoe roll

已成为广泛应用的产品
has become a widely used product

靴形压榨辊的压区上面
The corresponding pressure curve on

对应的压力曲线
the press area of the shoe press roll

如图所示
as shown in the figure

体现了其压力分布的三个特性区域
represents three characteristic areas of its pressure distribution

与靴形压榨辊配合使用的特型辊
Special roll used in combination with shoe press roll

可以采用可控中高胶面盲孔辊
can adopt controllable crown rubber surface blind hole roll

或者普通可控中高胶辊
or common controllable crown rubber roll

特型辊依靠液压
The special roll depends on the hydraulic pressure

保持转动辊壳的逆曲面
to keep the reverse surface of the rotating roll shell

并靠稳定而挠度可控的横轴
and produces the press load by the stable and horizontal

产生压榨负荷
axis with controllable flexural degree

可以采用这种浮动辊
The floating roll can be used

其结构特点是
Its structure is characterized by

有一转动的辊壳和不转动的芯轴
a rotating shell and a non-rotating mandrel

辊壳与芯轴之间的空间
The space between the roll shell and the mandrel is separated

被横向密封条分隔成上下两半腔体
into two upper and lower chambers by a transverse sealing strip

压力油从轴端进入
The pressure oil enters from the shaft end

调整油压可以控制辊壳的挠曲变形
adjusting the oil pressure to control the flexural deformation of the roll shell

这就是浮动辊的结构图
This is the structure of the floating roll

另外，特型辊也可以采用
In addition, the special roll can also adopt

分区可控中高辊
subarea and controlling crown rolls

这种辊子的结构特点是
The structure of the roll is characterized in that

在转动的辊壳内
a mushroom-shaped hydrostatic bearing piston

每隔一定距离设置一个
is arranged at a constant distance

蘑菇状的静压轴承活塞
within the rotating roll shell

在活塞内通入压力油时
When the pressure oil is introduced into the piston

活塞上升并对辊壳产生所需的压力
the piston rises and produces the required pressure on the roll shell

这种可控中高辊不但可以
This kind of controllable crown roll can not only

控制辊筒的中高量
control the crown of the roll

而且在一定程度上能控制
but also control the position of the maximum crown

最大中高量在辊筒上的位置
on the roll at a certain degree

即能适当地控制辊筒挠曲轮廓
that is, it can control the flexural profile of the roll properly

这就是福伊特Nipco可控中高辊的
This is the structure drawing and physical diagram of

结构图及实物图
Nipco controllable crown roll of Voith

除了以上介绍的这些压榨形式
In addition to these press forms described above

现在还有一些新的压榨技术在研究中
there are now a number of new press techniques under study

比如与靴形压榨配合使用的上辊
such as the upper roll used in conjunction with shoe press

采用脉冲干燥的方式
adopting pulse drying

能够在压区产生蒸汽
which can generate steam in the press area

将水分逐出纸页
and drive moisture out of the sheet

将这项技术在靴压中应用
The application of this technology in shoe press

与压榨结合
combined with press

移除的水分比传统的压榨相比要多很多
can remove much more moisture than traditional press

同时，能耗也降下来
and reduce energy consumption

不过，这项技术的不足在于
However, the disadvantage of this technology is that

它需要采用高级电源
it needs to use advanced power

如果能够解决这个问题
and if it can solve this problem

那么将对它更广泛的应用
it will have a positive effect

会有积极的促进作用
on its wider application

除了这个脉冲压榨
In addition to this pulse press

还有采用大型钢辊热压榨的方式
the large-scale steel roll hot press is also used

在压榨的同时进行加热
to heat when pressing at the same time

实现热压
to achieve hot press

可以改善纸页的脱水
which can improve the dehydration of sheet

这项技术已经在
This technology has been applied

高、低定量纸种的纸机上应用
in high and low quantitative paper machinery

典型的压榨加压为140-175kN/m
The typical press pressure is 140-175 kN/m

纸页干度可以达到52-56%
and the dryness of paper can reach 52-56%

以上就是有关双辊压榨内容的介绍
The above is about the introduction of double-roll press

包括最基本的平辊压榨
including the most basic flat roll press

真空压榨、沟纹压榨等
vacuum press, groove press, and so on

以及当前应用的重点——靴式压榨
as well as the key point in current application——shoe press

其中靴式压榨是纸机高速化的关键
In which, the shoe press is the key to the high-speed paper machinery

在现代造纸中具有重要的意义
which is of great significance in modern paper making

好，这节课我们就讲到这里
Well, that’s all about this lesson

谢谢大家
Thank you all