U.S. patent application number 14/243409 was filed with the patent office on 2014-10-23 for assembly for a device of a fiber web production line.
This patent application is currently assigned to VALMET TECHNOLOGIES, INC.. The applicant listed for this patent is Samppa Ahmaniemi, Tero Kovanen. Invention is credited to Samppa Ahmaniemi, Tero Kovanen.
Application Number | 20140314946 14/243409 |
Document ID | / |
Family ID | 48050539 |
Filed Date | 2014-10-23 |
United States Patent
Application |
20140314946 |
Kind Code |
A1 |
Ahmaniemi; Samppa ; et
al. |
October 23, 2014 |
Assembly for a Device of a Fiber Web Production Line
Abstract
An apparatus having a rod or a blade (21) for a device of a
fiber web production line, especially a rod-bed or a blade holder
or holder assembly for a rod or a blade (21) of a device for
coating or sizing a fiber web, particularly a paper or a board web,
which assembly comprises a holder (25), in which the rod or the
blade (21) is supported on the front side of the holder (25), and
which assembly has loading means (24). The assembly further
comprises sensors, in particular piezo sensors (10) located between
the rod or the blade (21) and the loading means (24) for measuring
the loading pressure of the rod or the blade (21) locally.
Inventors: |
Ahmaniemi; Samppa; (Muurame,
FI) ; Kovanen; Tero; (Haarajoki, FI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Ahmaniemi; Samppa
Kovanen; Tero |
Muurame
Haarajoki |
|
FI
FI |
|
|
Assignee: |
VALMET TECHNOLOGIES, INC.
Espoo
FI
|
Family ID: |
48050539 |
Appl. No.: |
14/243409 |
Filed: |
April 2, 2014 |
Current U.S.
Class: |
427/8 ;
162/263 |
Current CPC
Class: |
D21H 23/56 20130101;
D21H 23/78 20130101; D21H 25/08 20130101 |
Class at
Publication: |
427/8 ;
162/263 |
International
Class: |
D21H 23/56 20060101
D21H023/56 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 9, 2013 |
EP |
13162894 |
Claims
1. An assembly for a device for coating or sizing a paper or a
board web, the assembly comprising: a holder, having a front side
arranged to face a coating or sizing roll or a paper or a board web
to be coated, the holder having a back side opposite the front
side; a rod or a blade supported on the front side of the holder;
at least one loading device engaged with the rod or the blade for
loading the rod or blade in a direction away from the back side
toward the coating or sizing roll or paper or board web; and load
sensors located between the rod or the blade, and the at least one
loading device, for measuring the loading pressure on the rod or
the blade locally.
2. The assembly of claim 1 wherein the load sensors are piezo
sensors.
3. The assembly of claim 2 wherein the rod or the blade comprises a
rod; and further comprising: an insert removably and insertably
supported in a groove on the front side of the holder, the insert
having a front side arranged to face the coating or sizing roll or
the paper or board web; wherein the rod is rotatably supported in a
recess on the front side of the insert; and wherein the sensors are
located in between the insert and the holder on a side of the
insert opposite the recess on the front side of the insert.
4. The assembly of claim 2 wherein the rod or the blade comprises a
rod; wherein the rod is rotatably supported in a recess on the
front side of the holder; and wherein the sensors are located on
the back side of the holder for measuring pressure loading of the
rod.
5. The assembly of claim 2 wherein the rod or the blade comprises a
blade; further comprising: wherein the blade is supported on the
front side of the holder; and wherein the sensors are located in
between the blade and the holder for measuring pressure loading of
the blade.
6. The assembly of claim 5 wherein the at least one loading device
comprises a loading hose and wherein the sensors are located
between the blade and the loading hose for measuring pressure
loading of the blade.
7. The assembly of claim 2 wherein the at least one loading device
comprises a first loading device arranged to load the holder toward
the coating or sizing roll or paper or board web, and further
comprising: at least one second profiling loading device arrayed
along the holder to profile the blade or rod; and wherein the
sensors are located in the holder between the rod or the blade and
the at least one second profiling loading device.
8. The assembly of claim 2 wherein the load sensors comprise a
plurality of load sensors arrayed and spaced apart in a cross
direction of a web to be coated or sized.
9. The assembly of claim 8 wherein the load sensors comprise a
plurality of sensors each spaced apart a uniform distance, so
forming a band of sensors in the cross direction.
10. The assembly of claim 1 wherein the at least one loading device
acts on the rod or blade and the sensors located in a loading
direction in line with the rod or the blade, the loading direction
defined by a direction in which the at least one loading device
acts.
11. The assembly of claim 1 wherein the at least one loading device
comprises a loading tube or spindles located on a side opposite the
rod or the blade opposite the coating or sizing roll or a paper or
a board web to be coated.
12. A method of coating or sizing a paper or board web with a rod
or blade comprising the steps of: loading the rod or blade against
coating or sizing roll, or a paper or board web to be coated;
wherein the rod or blade a holder is held in a front side of a
holder the front side facing the coating or sizing roll, or the
paper or board web to be coated roll, so that the rod or a blade is
supported on the front side of the holder; loading with a load, the
rod or the blade in a direction toward the coating or sizing roll,
or the paper or a board web; sensing the load with piezo sensors
located between the rod or the blade, and the load; and measuring a
loading pressure on the rod or the blade, locally.
13. The method of claim 12 further comprising the steps of
transmitting measurement information from the sensors to a
receiver, and from the receiver transmitting the measurement
information to a control system; and controlling the loading the
rod or the blade directly or indirectly with the control
system.
14. The method of claim 12 further comprising continuously
measuring the loading pressure on the rod or the blade,
locally.
15. The method of claim 14 further comprising using continuously
measuring the loading pressure on the rod or the blade, locally for
troubleshooting equipment or during a start-up.
16. The method of claim 12 wherein the loading with a load, the rod
or the blade in a direction toward the coating or sizing roll, or
the paper or a board web is adjusted manually or automatically
based on a cross-directional profile of the loading pressure based
on measuring the loading pressure on the rod or the blade,
locally.
17. A method of upgrading an apparatus for coating or sizing a
paper or board web with a rod or a blade, the method comprising;
installing load sensors located between a rod or a blade and at
least one loading device, wherein the rod or blade is supported on
a front side of a holder, the front side arranged to face a coating
or sizing roll or the paper or board web, and the at least one
loading device is arranged engaged with the rod or the blade for
loading the rod or blade in a direction toward the coating or
sizing roll or paper or board web; measuring loading pressures on
the rod or the blade locally; and using an expert service to adjust
loading on the rod or the blade in a direction toward the coating
or sizing roll, or the paper or board web based on the loading
pressures as measured.
Description
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] This application claims priority on European Application No.
EP 13162894, filed Apr. 9, 2013, the disclosure of which is
incorporated by reference herein.
STATEMENT AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSORED
RESEARCH AND DEVELOPMENT
[0002] Not applicable.
BACKGROUND OF THE INVENTION
[0003] The present invention relates to an assembly comprising a
rod or a blade for a device of a fiber web production line,
especially to a rod-bed or a blade holder assembly for a rod or a
blade of a device for coating or sizing a fiber web, particularly a
paper or a board web, especially a rod-bed or a blade holder or
holder assembly for a rod or a blade of a device for coating or
sizing a fiber web, particularly a paper or a board web, which
assembly comprises a holder in which the rod or the blade is
supported on the front side of the holder, and which assembly has a
loading device.
[0004] As known from the prior art in fiber web producing processes
typically comprise an assembly formed by a number of apparatuses
arranged consecutively in the process line. A typical production
and treatment line comprises a head box, a wire section and a press
section as well as a subsequent drying section and a reelup. The
production and treatment line can further comprise other devices
and sections for finishing the fiber web, for example, a sizer, a
calender, a coating section. The production and treatment line also
comprises at least one winder for forming customer rolls as well as
a roll packaging apparatus. In this description and the following
claims by fiber webs are meant for example paper and board
webs.
[0005] In production of fiber webs, for example of paper or board
webs, sizing is used to alter the properties of a fiber web by
adding sizing agents (sizing medium), for example glue chemicals.
Sizing can be divided to internal sizing and surface sizing. In
internal sizing the sizing agent is added to pulp in the wet end of
the fiber web machine before forming. In surface sizing the sizing
agent is added onto the surface of the fiber web at the fiber web
machine.
[0006] In production of fiber webs, for example of paper or board
webs, coating, especially the surface of a fiber web is formed with
a layer of coating paste (coating medium) at a coating station
followed by drying. The coating process can be divided in supplying
the coating paste onto the web surface, which is called the
application of the coating paste, as well as in the adjustment of
the final amount of coating paste.
[0007] The coating or the sizing of a fiber web typically utilizes
a coating device--a coater--or a sizing device--a sizer. In
connection with the coaters and sizers different kinds of
application technology for application of the coating medium or the
sizing medium on the fiber web are employed, for example curtain
technology or blade coating technology or film transfer technology
or rod coating technology or air brush coating technology or spray
coating technology.
[0008] In the coating or sizing based on rod technology, rod-bed
assemblies are used for the rod functioning as a dosing element of
the coating or sizing medium for scraping off the excessive medium
quantity of the sizing or coating medium. In the sizing the rod
functions against a roll and in the coating the rod functions
against the fiber web. The rod coating or sizing assembly is
composed of a rod and of a rod-bed comprising a holder to which the
rod is attached directly or by means of an insert that is fitted
into the holder for the rod. The rod-bed is in turn attached to a
beam or corresponding support structure arranged on the frame of
the machine.
[0009] A web of paper or paperboard can be coated or surface sized
using film-transfer or blade technology, wherein the web being
treated is passed through a nip between two opposed rolls. The
coating or sizing medium is applied with the help of a suitable
applicators to the surface of one or both of the nip-forming rolls,
wherefrom the substance is transferred to the surface of the web
being treated in the nip between the rolls. The thickness and
cross-machine profile of the coating or sizing medium layer applied
to the roll surface are controlled by a blade or rotatable rod.
[0010] In the coating or sizing based on blade or film transfer
technology the blade or rod is attached to a holder. The holder
with accompanying support and fastening means is in turn attached
to a beam or corresponding support structure arranged on the frame
of the machine.
[0011] Typically the beam or corresponding support structure of a
coating/sizing rod/blade is arranged movable by loading means
arranged at each end of the beam or corresponding support structure
by which the main loading of the blade or rod is provided. In the
cross direction of the web to be coated or sized the loading of the
blade or rod is typically arranged by profiling loading means for
example by spindles that load cross-directional means for example a
loading hose (a hose-loaded blade) and/or by a rigid loading plate,
which spindles are spaced apart at certain intervals at the cross
direction of the fiber web to be coated or sized.
[0012] In a hose-loaded blade or rod in a fiber web machine in
coating or sizing devices, the contact force of the blade or rod on
the opposing surface is increased by means of loading hoses acting
on the blade or rod holder. Loading hoses normally have an oval
cross-section. The loading hose is set between the holder and its
support.
[0013] In coating and sizing utilizing the dosing of the coating or
sizing medium, especially the quality and profile of the medium is
controlled by automatically or manually controlling the surface
pressure created by the rod or the blade by means of the loading
means and the profiling loading means. The surface pressure between
the rod or the blade and the counter roll is not directly measured
but instead the adjustments needed are done based on measurements
of the fiber web and its coating/sizing layer.
[0014] The rod or the blade are loaded by adjusting pressure of a
loading tube that is supported on a frame of the holder or by
adjusting the rigid loading plate supported on a frame of the
holder. The loading presses the back of the holder and the rod or
the blade towards the web to be coated or towards the corresponding
coating or sizing roll, in order to build up the contact pressure
of the rod or the blade against the web or against the roll. In
many loading tube arrangements there is also a loading plate or
corresponding support plate on the back side (on the opposite side
in respect of the holder) of the loading tube that is locally
loaded by loading elements, for example by spindles that are spaced
apart at certain intervals at the cross direction of the fiber web
to be coated or sized. There are also loading constructions in
which no loading hose is used and instead the loading is arranged
by means of the loading plate and the spindles. The spindles are
adjusted manually or automatically based on a scanning measurement
device located after the coater or the sizer. Thus there is no
knowledge of the actual value of the loading pressure of the rod or
the blade locally.
[0015] The lack of knowledge of the actual values makes the
automatic control difficult and unreliable to use as typically the
profile information received from the measurement device, for
example from a scanning measurement frame is unreliable and not
exact enough for profile adjustment of coating or sizing in desired
accuracy.
[0016] By using manual control a required quality level of coating
or sizing is typically achieved but locally the pressure may vary
considerably, which might locally cause wear in rod and other
surfaces.
[0017] As a summary one of the main problems is that the actual and
real knowledge of the local loading information of the rod or the
blade is not available and thus the adjustments and control of
coating or sizing must be done based on indirect information.
[0018] Many of the above problems and disadvantages occur in
coating and sizing irrelevant of the technology type used even
though they have been in some cases described in reference to one
example only.
[0019] In WO 2010099830 is disclosed a blade for doctoring a moving
surface or for sizing or creping a fiber web produced or finished
in a web machine, especially in a paper, board or tissue machine,
which comprises at least one fiber optical waveguide being arranged
on a surface of the blade or embedded in the material of the blade.
Disadvantageous of this arrangement is that during use the blade
wears and thus at regular intervals a new blade must be changed. A
blade with a fiber optical waveguide is expensive thus the changing
costs increase. In cases where the fiber optical waveguide is
arranged on the surface of the blade also the waveguide may wear
and thus its signal level may change and on the surface the
waveguide is susceptible to damage.
[0020] In US 2005223513 is disclosed a calibration device for the
pressure of a scraping device blade, which abuts the periphery of a
roll or a cylinder, in particular of a paper machine, a printing
machine, a calender or the like, comprising a holding blade, a
sensor holder mounted thereto, and a pressure sensor, for example a
piezo element are positioned such that the position of the pressure
sensor on the periphery of the roller or cylinder corresponds to
the position of abutment of the blade. Disadvantageous of this
arrangement is that it is suitable for calibrating and testing in
service situations but it is not suitable to be used during
process. Further, as in the above case the sensor mounted on the
blade increases the changing cost of the blade, which as a wear
part changed regularly should be cost effective.
SUMMARY OF THE INVENTION
[0021] An object of the present invention is to create an assembly
comprising a rod or a blade for a device of a fiber web production
line in which the disadvantages of devices known from prior art are
eliminated or at least minimized.
[0022] Yet another object of the present invention is to provide a
rod-bed or a blade holder for a rod or a blade of a device for
coating or sizing a fiber web, particularly a paper or a board web,
in which the actual value of the loading pressure of the rod
locally is received.
[0023] In this description and the claims, by front side of the
holder is meant the side on which the rod or the blade is located
i.e. the side that is facing the web to be treated or the roll onto
which the coating or sizing medium is applied and corresponding by
the back side the side on which the loading means are located and
which is facing the beam or corresponding support structure on
which the holder is attached.
[0024] In order to achieve the above objects and to solve the
problems of prior art mentioned above and coming apparent later an
assembly comprising a rod or a blade for a device of a fiber web
production line, especially to a rod-bed or a blade holder assembly
for a rod or a blade of a device for coating or sizing a fiber web,
particularly a paper or a board web according to the invention is
mainly characterized by sensors, in particular piezo sensors,
located between a rod or a blade and a loading means for measuring
the loading pressure of the rod or the blade locally.
[0025] According to the invention the assembly comprises a holder,
in which a rod or a blade is supported on the front side of the
holder, and loading means and sensors, in particular piezo sensors,
located in the holder between the rod or the blade and the loading
means for measuring the loading pressure of the rod or the blade
locally. Advantageously the sensors are located spaced apart at
certain intervals at the cross direction of the fiber web to be
coated or sized.
[0026] According to an advantageous feature of the invention a
cross-directional profile of the loading pressure is provided based
on the measurement information and based on the profile information
the loading means are adjusted manually or automatically to load
such that desired profile is provided in coating or sizing.
[0027] According to an advantageous feature the loading means
comprise main loading means and profiling loading means.
[0028] According to an advantageous feature the sensors, in
particular piezo sensors, are located in the holder between the rod
or the blade and the profiling loading means for measuring the
loading pressure of the rod or the blade locally.
[0029] According to an advantageous aspect of the invention the
rod-bed assembly comprises a holder, an insert removably and
insertably supported in a groove of the holder and in which rod-bed
assembly a rod of a coating or sizing or device is rotatably
supported in a recess on the front side of the insert, which
rod-bed assembly further comprises sensors, in particular piezo
sensors, located in between the insert and the holder on the
opposite side of the insert in respect of the rod located in the
insert for measuring the loading pressure of the rod.
[0030] According to another advantageous aspect of the invention
the rod-bed assembly comprises a holder, in which a rod of a
coating or sizing or device is rotatably supported in a recess on
the front side of the holder, which rod-bed assembly further
comprises sensors, in particular piezo sensors located on the back
side of the holder in respect of the rod for measuring the loading
pressure of the rod.
[0031] According to another advantageous aspect of the invention
the blade holder assembly comprises a holder and a blade supported
in the holder, which assembly further comprises sensors, in
particular piezo sensors, located between the blade and the loading
means for measuring the loading pressure of the blade.
[0032] According to an advantageous feature in cases where the
blade holder assembly comprises a loading hose and its loading
means, the sensors, in particular the piezo sensors are located
between the blade and the loading hose and/or between the loading
hose and its loading means.
[0033] According to another advantageous feature in cases where the
blade holder assembly or the rod-bed assembly comprises a rigid
loading or support plate and its loading means, the sensors in
particular the piezo sensors, are located between the blade or the
rod and the rigid loading or support plate and/or between the
loading or support plate and its loading means.
[0034] According to an advantageous feature of the invention the
sensors, in particular piezo sensors are located spaced apart in
the cross direction of the web to be coated or sized desired
intervals.
[0035] According to an advantageous feature of the invention the
sensors, in particular piezo sensors, are located in a band
comprising a number of spaced apart sensors.
[0036] According to an advantageous feature of the invention the
sensors, in particular piezo sensors, are located in the loading
direction of the rod or the blade in line with the rod or the
blade.
[0037] The assembly comprises as loading means a loading tube and
spindles loading the loading tube located on the opposite side in
respect of the rod or the blade placed in the holder of the
assembly i.e. on the back side of the holder. According to an
advantageous feature the assembly has means for transmitting the
measurement results of the sensors, in particular piezo sensors, to
control means for controlling the loading means, in particular the
spindles for regulating the pressure of the loading tube. The
sensors are located aligned with the spindles correspondingly
spaced apart.
[0038] According to an advantageous feature the assembly according
to the invention is used as an upgrade kit of the assembly, in
which the upgrade kit comprises as an expert service arranged
measurement with the assembly and adjustment of the loading means
to load the rod or the blade to provide the desired profile.
[0039] The assembly according to the invention is applicable in
connection with continuous measurements or as troubleshooting
equipment or during a start-up of a new device. By the invention
many advantages are achieved the profiling of the dosing of the
coating or sizing medium by the rod or the blade is improved. The
locally existing peaks of loading can also be avoided and thus the
wear of the rod or the blade, the rod-bed or the holder and the
coating or sizing roll is decreased and thus the service time of
the same increased.
[0040] In case the invention is used in connection with a start-up
of a new device by utilizing the invention the required quality
level is achieved fast and thus the production can begin in a
shorter time.
BRIEF DESCRIPTION OF THE DRAWINGS
[0041] FIG. 1A is schematically shown an example of the invention
in connection with a rod-bed assembly comprising an insert,
[0042] FIG. 1B is schematically shown an example of the invention
in connection with a rod-bed assembly without an insert,
[0043] FIGS. 2A and 2B are schematically shown examples of the
invention in connection with a blade holder assembly,
[0044] FIG. 3 is schematically shown an example of loading and
profiling arrangement in a coater or in a sizer
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0045] In the following the invention is described referring to the
examples of FIGS. 1A-3 to details of which the invention is not to
be narrowly limited. In the figures and the description by the same
reference signs are indicated corresponding parts and part
components unless otherwise mentioned.
[0046] In FIG. 1A is schematically shown an example of the
invention in connection with a rod-bed assembly. The rod-bed
assembly comprises a holder 13, and an insert 12 removably and
insertably supported in a groove 14 of the holder 13. In which
rod-bed assembly a rod 11 of a coating or a sizing device is
rotatably supported in a recess 15 on the front side of the insert
12, which rod-bed assembly further comprises sensors, in particular
piezo sensors 10, located in between the insert 12 and the holder
13 on the opposite side of the insert 12 in respect of the rod 11
located in the insert 12 for measuring the loading pressure of the
rod 11. The sensors, in particular the piezo sensors 10 transmit
measurement information to a receiver 31, which transmits the
measurement information to a control system 32, which can directly
or indirectly control the loading means (FIG. 3) of the rod-bed
assembly.
[0047] In FIG. 1B is schematically shown an example of the
invention in connection with a rod-bed assembly. The rod-bed
assembly comprises a holder 13 and in which a rod 11 of a coating
or a sizing device is rotatably supported in a recess on the front
side of the holder 13, which rod-bed assembly further comprises
sensors, in particular piezo sensors 10 located on the back side of
the holder 13 on the opposite side in respect to the rod 11 for
measuring the loading pressure of the rod 11. The sensors, in
particular piezo sensors 10 transmit measurement information to a
receiver 31, which transmits the measurement information to a
control system 32, which can directly or indirectly control the
loading means (FIG. 3) of the rod-bed assembly.
[0048] In FIGS. 2A and 2B are schematically shown examples of the
invention in connection with a blade holder assembly and the blade
holder assembly comprises a holder 25 and a blade 21. The assembly
further comprises sensors, in particular piezo sensors 10 located
between the blade 21 and a loading means, for measuring the loading
pressure of the blade 21. The sensors, in particular piezo sensors
10 transmit measurement information to a receiver 31, which
transmits the measurement information to a control system 32, which
can directly or indirectly control the loading means 24 shown in
FIG. 3 of the rod-bed assembly.
[0049] In the example of FIG. 2A in the blade holder assembly the
loading means is a loading hose 24 and the sensors are piezo
sensors. The sensors 10 are located between the blade 21 and the
loading hose 24 and/or between the blade and the loading means
behind the loading hose 24 in the holder 25. The sensors, in
particular piezo sensors 10, transmit measurement information to a
receiver 31, which transmits the measurement information to a
control system 32, which can directly or indirectly control the
loading means of the blade holder assembly.
[0050] In FIG. 2B the sensors 10 are located between the blade 21
and the holder 25. The sensors, in particular piezo sensors 10,
transmit measurement information to a receiver 31, which transmits
the measurement information to a control system 32, which can
directly or indirectly control the loading means of the blade
holder assembly.
[0051] In FIG. 3 is schematically shown an example of the loading
arrangement in a coater or a sizer. By reference number 30 is
indicated a roll of the coater or of the sizer. Main loading
devices 26 e.g., pistons, are located at each end of the frame
structure 29. The assembly with the rod or the blade is attached to
the frame structure by its rod-bed assembly or blade holder
assembly and is located in the view of FIG. 3 behind the frame
structure 29 opposing the roll 30 such that when loaded the rod or
the blade are in loading pressure contact with the roll 30, i.e.
for dosing the coating or sizing medium on the roll 30. To the
frame structure 29 is attached a loading or support plate 28
extending in a cross direction, i.e. horizontally in the view of
FIG. 3. The profiling loading means 27, for example spindles 27,
are located to load the loading or support plate 28 in the cross
direction. The profiling loading means 27 are thus located spaced
apart in the cross direction. The sensors, in particular piezo
sensors, transmit measurement information to a receiver 31, which
transmits the measurement information to a control system 32, which
can directly or indirectly control the loading means 26, 27 of the
rod-bed assembly.
[0052] Above the invention has been explained in view of some
advantageous examples only and many modifications in the examples
and in the details of the examples are possible.
* * * * *