U.S. patent number 3,861,997 [Application Number 05/317,244] was granted by the patent office on 1975-01-21 for paper machine press arrangement with stacked press rolls.
This patent grant is currently assigned to Beloit Corporation. Invention is credited to Donald A. Ely.
United States Patent |
3,861,997 |
Ely |
January 21, 1975 |
PAPER MACHINE PRESS ARRANGEMENT WITH STACKED PRESS ROLLS
Abstract
A press section for a paper making machine includes a first felt
receiving a web from a fourdrinier and passing through a first nip
formed between first and second press rolls with a second felt
passing through the first nip and wrapping the second roll while
passing through a second nip formed between a third and the second
press roll with the web being carried by the second felt through a
third press nip formed between additional press rolls.
Inventors: |
Ely; Donald A. (Roscoe,
IL) |
Assignee: |
Beloit Corporation (Beloit,
WI)
|
Family
ID: |
23232771 |
Appl.
No.: |
05/317,244 |
Filed: |
December 21, 1972 |
Current U.S.
Class: |
162/360.3;
100/159; 162/364 |
Current CPC
Class: |
D21F
3/04 (20130101) |
Current International
Class: |
D21F
3/02 (20060101); D21F 3/04 (20060101); D21f
003/04 () |
Field of
Search: |
;162/358,360,205,364
;100/121,158,159 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
293,520 |
|
Jan 1914 |
|
DD |
|
699,107 |
|
Dec 1964 |
|
CA |
|
Primary Examiner: Bashore; S. Leon
Assistant Examiner: Fisher; Richard V.
Attorney, Agent or Firm: Hill, Gross, Simpson, Van Santen,
Steadman, Chiara & Simpson
Claims
I claim as my invention:
1. In a paper making machine, the combination including:
a forming section;
a perforate first press roll immediately following said forming
section;
a perforate second press roll forming a first nip with the first
roll on the upper side of said first roll;
a third press roll forming a second nip with the second roll
substantially opposite said first nip relative to the axis of said
second roll;
a first felt for carrying a paper web extending horizontally from
the forming section and engaging the bottom of the first roll,
wrapping substantially 180.degree. and threaded through said first
nip with the web carrying side facing the second roll;
a suction gland within the first roll opposite the wrap of the
first felt;
a second felt threaded through said first nip and wrapping the
second roll continuously between said first and second nip and
passing through the second nip with the web carried on the outer
surface of the second felt between the first and second nip;
a suction gland within the second press roll opposite the second
felt;
a roll couple forming a third press nip;
said second felt extending from the second nip to the third nip and
carrying the web through the third nip.
2. In a paper making machine constructed in accordance with claim
1, the combination:
including a third felt threaded through said second nip so that the
second nip is a double-felted nip.
3. A press section for a paper making machine constructed in
accordance with claim 1:
wherein the roll of said roll couple supporting said second felt is
a grooved roll.
4. A press section for a paper making machine comprising in
combination:
a perforate first press roll;
a perforate second press roll shell forming a first nip with the
first roll;
a third press roll forming a second nip with the second roll shell
positioned after the first nip located substantially opposite the
first nip relative to the axis of the second roll;
a first felt for receiving and carrying a paper web on a web
carrying surface thereof through the first nip with the web
carrying surface facing the second roll; said first felt extending
substantially horizontally to the first roll and wrapping the first
roll for substantially 180.degree. ;
a suction gland within the first roll opposite the first felt;
and a second felt also threaded through said first nip with the web
between the first and second felts in said first nip;
a suction gland within the second roll shell extending over the
portion wrapped by the second felt;
said second felt wrapping the second roll continuously between nips
and passing through the second nip with the web carried on the
outer surface of the second felt between the first and second
nip.
5. A press section for a paper making machine constructed in
accordance with claim 4:
and including a fourdrinier forming section ahead of the press
section with said first felt arranged in pick-up relation with the
fourdrinier forming wire to receive the web therefrom.
6. A press section for a paper making machine constructed in
accordance with claim 4:
wherein third press roll has a plurality of grooves formed in the
outer surface thereof.
7. A press section for a paper making machine constructed in
accordance with claim 4:
and including a short separate suction gland positioned on the
offrunning side of the first nip for insuring the transfer of the
web from the first to the second felt.
8. A press section for a paper making machine constructed in
accordance with claim 4:
and including a third felt passing through said second nip with the
web passing between said first and second felts so that the second
nip is a double felted nip.
9. A press section for a paper making machine constructed in
accordance with claim 8:
including means for causing the web to follow the second felt after
the second nip.
Description
BACKGROUND OF THE INVENTION
The present invention relates to improvements in paper making
machines and more particularly to an improved press section for
forming an improved web which press section is particularly adapted
to dewatering paper having an absence of two sidedness such as is
formed on twin wire paper making machines.
In the formation of paper webs of many types including newsprint
and other papers, there is a necessity of avoiding two-sidedness. A
paper web which has uniform physical characteristics on both sides
is superior for all types of paper to receive printing. Twin wire
forming sections have increased the uniformity of paper and it is
essential that the other parts of the paper making machine keep
pace and not disturb or destroy the uniform characteristics of the
two surfaces by adverse dewatering effects.
In a press section where substantial amounts of water are removed
from the web, severe dewatering in either direction can adversely
affect the uniformity of the web. Uniform treatment of both sides
of the paper from a dewatering standpoint is also important from
the aspect of increasing the amount of water removed and thereby
reducing the amount of heat energy needed to be put into the dryer
section for dewatering in that section of the machine.
It is also important in modern high-speed paper making machines to
provide press sections which are compact and short as possible to
reduce the necessary length of the machine and reduce the handling
which the paper web must receive. If the press nips can be placed
very close together in succession, the amount of handling the web
requires will be reduced. It is also advantageous to reduce open
draws or transfers along the machine, or control of the web may be
lost requiring a shut-down of the paper making machine. Such
shut-downs are expensive and highly disadvantageous on a high-speed
machine.
It is accordingly an object of the present invention to provide an
improved press section which obtains an improved product and which
contributes to the uniformity of both sides of the web.
A further object of the invention is to provide an improved paper
machine press section which is complementary to a twin wire machine
and which obtains optimum dewatering of the web with substantial
uniformity from both directions.
A still further object of the invention is to provide an improved
paper making machine which has a press section that is very compact
and avoids open draws along runs so that control of the web is not
lost.
Other objects, advantages, as well as equivalent structures which
are intended to be covered herein, will become more apparent with
the teaching of the principles of the present invention in
connection with the disclosure of the preferred embodiment in the
specification, claims and drawings, in which:
DESCRIPTION OF THE DRAWINGS
The FIGURE of the drawing is a somewhat schematic side elevational
view showing a press section of a paper making machine constructed
and operating in accordance with the principles of the present
invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A paper web is formed and carried on the surface of a traveling
fourdrinier 10. In many instances the fourdrinier section of the
machine will be a twin wire section so that the finished web will
be substantially uniform on both sides. The web is carried through
a machine and its position is indicated at W. The fourdrinier wire
travels over a couch roll 11 and a turning roll 12, and in a
downrunning section of the wire 10a, the web is picked off the
surface of a first felt 13. The felt is formed in a loop and
travels over a number of supporting guide rolls which are not
numbered. For picking the web off the wire 10, the felt 13 passes
over a pick-up roll 14 having a suction gland 15 therein.
The web then travels on the lower surface of the felt to pass
through a first press nip at N-1. The first nip is a double felted
nip with the web being carried between the first felt 13 and a
second felt 27. The first nip is formed between first and second
press rolls 16 and 18 respectively.
The first felt is wrapped over the first press roll 16. The first
press roll is a suction roll with a gland 17 to aid in the
extraction of water from the web and transfer to the felt 13.
The second press roll 18 is wrapped by the second felt 27. The web
in passing through the first nip N-1 follows the second felt 27 and
is transferred to the felt as aided by the first suction gland 19
positioned at the outgoing side of the first nip N-1.
The web is carried on the outer surface of the second felt 27 to
pass through a second nip N-2.
To aid in carrying the web on the outer surface of the felt 27
while it is wrapping over the second roll 18, a suction gland 20 is
positioned opposite the felt. The second nip is formed between the
second roll 18 and a third press roll 21. The third press roll has
grooves 22 on its outer surface to aid in the transfer of water to
a third felt 23 which also passes through the second nip N-2. The
second nip is also a double-felted nip.
Suitable guide rolls for the second felt 27 and the third felt 23
are provided which need not be described in detail. Suitable felt
dewatering means will be provided along the felt loop for removing
water therefrom after the felt leaves the nip and before it returns
to the nip.
Following the second nip N-2, the web is carried on the upper
surface of the second felt 27 to a third nip N-3. It will be noted
that the first and third press rolls 16 and 21 are substantially
180.degree. apart relative to the intermediate second press roll
18. The nip forces due to the first and third rolls are
diametrically opposed and balance each other to reduce the tendency
of the intermediate roll 18 to bend, thereby making it possible to
use a suction roll and yet obtaining relatively high nip
pressures.
It will also be noted that the first and second nips N-1 and N-2
are relatively close together and that the web is completely
controlled by being held to the second felt 27 in the run between
the two nips. Following the second nip the web is on the upper
surface of the second felt 27 with it passing downwardly so that
there is no possibility of the web coming off the felt or getting
out of control.
The third nip is formed between a roll couple including an upper
press roll 24 and a lower press roll 26. The lower press roll is
grooved shown at 25 to aid in the water being transferred from the
web, which is on the upper surface of the felt 27, to the felt.
Following the press section, the web will be carried by suitable
felts, not shown in detail, to the dryer section of the machine,
after which it will travel through a calender and then be wound on
a roll.
* * * * *