5
Title of Invention
EQUIPMENT OF SUPPLYING LUBRICANT AND METHOD OF
SUPPLYING LUBRICANT
Technical Field
[00011 The present invention relates to a facility and
method of supplying a lubricant which is used in a
10 rolling process, in particular a hot rolling process, in
a process of production of steel sheet/strip, steel
plate, or other ferrous metal products.
Background Art
15 [00021 In a hot rolling process in a process of
production of steel sheet/strip, steel. plate, or other
ferrous metal products, lubricated rolling is performed
for lightening the load on the rolling rolls which are
used as working tools, reducing wear or seizing and the
20 occurrence of defects caused along with the wear or
seizing, securing good surface quality of the products,
and various other purposes.
[00031 In the hot rolling process, mainly, the method
of using the water injection method to spray and supply a
25 mixture of water and lubricant in an emulsion state (for
example, see NPLT 1) to the roll, and the method of
supplying grease or other semisolid lubricants by air or
another gas to deposit it on the rolls, etc. have been
used (for example, see PLT 1)0
30 [0004] As other lubricated rolling methods, the method
of directly pressing a solid form lubricant, which is
made by mixing graphite or another solid lubricant with
wax, to the roll surface (for example, see PLT 2), and
the method of supplying a non-oil type lubricant, which
35 is made by mixing various additives with a colloidal
solution, to the rolls or roll bite, etc. are also known.
[000-51 Further, in recent years, as a method of
supplying a lubricant not using water, the method of
rendering, not a semisolid grease, but a liquid lubricant
which is used in the water injection method into an
atomized or particulate state and spraying and supplying
5 this to a roll together with a noncombustible gas has
been proposed (PLT 3, below, this method called the "gas
atomization method"). According to this method, a small
amount of lubricant supply enables a large effect of
reduction of the coefficient of friction to be obtained.
10 Furthermore, equipment for lubrication and a method of
lubrication for using the gas atomization method in hot
rolling of steel sheet/strip have also been proposed (for
example, see PLT 4)a
[0006] On the other hand, to supply a sufficient
15 amount of lubricant to the parts in which lubrication is
required during rolling, usually a rolling mill is
provided with a plurality of spray nozzles for lubricant
supply. A hot rolling mill for steel sheet/strip, as
illustrated in PLT 1 or PLT 4, is provided with a
20 lubrication header comprised of a plurality of spray
nozzles aligned in the product width direction. Such a
configured lubrication header is 'designed to enable a
lubricant to be supplied to the entire region where a
roll and steel material contact each other. This
25 lubrication header, while differing depending on the size
of the rolling mill, has at least two spray nozzles which
are set at substantially equal intervals and in
accordance with need is provided with a mechanism which
enables selection of the spray nozzles to be used.
30 [0007] Such a lubrication header is usually
individually provided for each of the upper and lower
work rolls and backup rolls. However, depending on the
operating conditions of the rolling processes, sometimes
it is set for just one of the upper and lower work rolls
35 or backup rolls. In either case, when using such a
lubrication header for lubricated rolling, at the
present, at least two spray nozzles are used in one
rolling mill for each pass so as to supply the lubricant.
[00081 Regarding the device for feeding a lubricant to
the spray nozzles, in the water injection method, as
shown in FIG. 1, water and a lubricant are fed by
5 separate pumps, that is, a water--feed pump device 3' and
a lubricant-feed pump device 3, to a mixer of water and
lubricant called an "injector 8". The amount of fed water
and lubricant at this time are set so that the emulsion
which is produced at the injector 8 becomes a
10 predetermined concentration. The emulsion of the
predetermined concentration which is produced at the
injector 8 is fed through pipes which are branched in the
span from the injector 8 to the spray nozzles "1' to be
fed to the plurality of spray nozzles 1'.
15 [0009] The lubricant concentration of the emulsion is,
in hot rolling of steel sheet/strip, 0.2 to 1 vol. or so.
The amount of the supplied emulsion as a whole reaches
several liters to tens of liters per minute per pass.
[0010] To supply such a large amount of emulsion, a
20 relatively high pressure has to be applied to spray it
from the spray nozzles. Therefore, the speed of feed of
the emulsion in the pipes is large, and thus there is no
time for the emulsion to separate into water and a
lubricant, so the spray nozzles are fed comparatively
25 evenly with substantially the same amounts of emulsion
which are then sprayed to the roll. Therefore, in the
case of the water injection method, for convenience in
laying the piping, equipment for supplying a lubricant
which is provided with two sets of pump devices for upper
30 roll and lower roll is usually used. One set of pump
devices is used to feed emulsion to two or more spray
nozzles.
[0011] Regarding the gas atomization method, equipment
for supplying a lubricant and method of supplying a
35 lubricant which use a lubrication header which is
provided with so-called internal mixing type two-fluid
spray nozzles which are provided with mixing chambers at
which the lubricant and gas are mixed inside the spray
nozzles are disclosed in PLT 4. With this equipment of
supplying a lubricant and method of supplying a
lubricant, the lubricant is fed to the spray nozzles as
5 much as possible without pressure in the lubricant pipes.
Gas of less than 005 bar (0005 MPa) is used to render the
lubricant into a particulate or atomized state and spray
and supply it from the spray nozzles.
[00121 PLT 6 discloses a method of supplying a
10 lubricant and equipment for supplying a lubricant which
are designed to prevent scatter even if floating mist not
deposited on the roll is formed when rendering a
lubricant to the particulate or atomized state and
spraying and supplying it from the spray nozzles by the
15 gas atomization method. In the system described in PLT
6, an air spraying mechanism is provided as a secondary
nozzle at the outside of the flow paths of the spray
nozzles through which the lubricant is sprayed. At the
time of spraying the lubricant, air is blown from the air
20 spraying mechanism to form a wall of air to thereby
suppress splatter of the floating mist.
Citations List
Patent Literature
25 [00131 P1_T 1: Japanese Patent Publication No. 2002--
316202 Al
30
PLT 2: Japanese Patent Publication No. 2000®197901 Al
PLT 3: Japanese Patent Publication No. 2003--94104 Al
PLT 4: International Publication No. 2009/046505
PLT 5: Japanese Patent Publication No. 07-290121 Al
PLT 6: Japanese Patent Publication No. 2008-213023 Al
Non Patent Literature
[0014] NPLT 1: the Iron and Steel Institute of Japan,
35 "Theory and Practice of Flat Product Rolling", p. 218
Summary of Invention
Technical Problem
[0015] In this regard, in rolling of a metal material,
in particular hot rolling of steel sheet/strip, uneven
wear and roughness occur in the axial direction of a
5 rolling roll. However, when using the water injection
method, as explained above, it becomes necessary to
supply a large amount of lubricant as the emulsion state
to the roll, and thus it is difficult to adjust the
amount of lubricant supplied locally in the axial
10 direction of a rolling roll and impossible to suppress
uneven wear or roughness in the axial direction.
[0016] Further, with the method which uses the gas
atomization method which is described in PLT 4, a
lubricant is fed from a lubricant distributor to the
15 spray nozzles. Basically, the same amounts of lubricant
are fed from the spray nozzles. Further, no consideration
is given to adjusting the amount of lubricant supplied
locally in the axial direction of the rolling roll. It is
not possible to suppress uneven wear or roughness in the
20 axial direction.
[00171 Therefore, an object of the present invention
is to provide equipment for supplying lubricant and
lubricant supply method which can locally adjust the
amount of lubricant supplied in an axial direction of a
25 rolling rol]. to thereby effectively suppress uneven wear
or roughness in the axial direction.
Solution to Problem
[0018] The inventors engaged in intensive studies to
30 solve'the above problem by the feed of a lubricant by the
gas atomization method and as a result obtained the
following discoveries.
Uneven wear and roughness at the rolling roll
surface easily occur near the roll surface where the
35 vicinities of the ends, in the width direction, of the
rolled material, that is, the steel sheet, contact.
Therefore, by relatively increasing the amounts of
6
spray of a lubricant near the contacting parts at the
ends of the steel sheet and relatively decreasing the
amounts at the center of the steel sheet as the basic
pattern of distribution, it is possible to efficiently
5 avoid uneven wear and roughness of the roll.
[00191 The present invention was made based on these
discoveries and has as its gist the following.
(1) Equipment for supplying a lubricant for a rolling
roll of a rolling mill for a flat shaped metal material,
10 comprising: a plurality of spray nozzles which are
arranged in an axial direction of the rolling roll and
which spray a lubricant toward the rolling roll together
with a gas in a particulate or atomized state; a
lubricant feed device which feeds a lubricant to the
15 spray nozzles; and a gas feed device which feeds a gas to
the spray nozzles, wherein when designating, the spray
nozzles which are positioned at the both ends among the
spray nozzles which supply a lubricant to the parts of
the rolling roll corresponding to the width of the flat
20 shaped metal material as the side spray nozzles and
designating the spray nozzles which are positioned at the
center as the center spray nozzles, the amount of
lubricant supplied from the side spray nozzles are larger
than the amount of lubricant supplied from the center
25 spray nozzles and the amount of lubricant supplied from
the spray nozzles between these side spray nozzles and
center spray nozzles are not more than the amount of
lubricant supplied from the side spray nozzles and not
less than the amount of lubricant supplied from the
30 center spray nozzles.
Note that, the "amount of a supplied lubricant"
means the amount of lubricant which is fed per unit
surface area of the rolling roll per unit time.
[00201 (2) Equipment for supplying a lubricant for
35 rolling mill as set forth in (1), wherein the amount of
lubricant supplied from the spray nozzles between these
side spray nozzles and center spray nozzles become
smaller from the sides toward the center of the rolling
roll.
(3) Equipment for supplying a lubricant for rolling mill
as set forth in (1) or (2), wherein the amount of
5 lubricant supplied from the side spray nozzles are up to
5 times the amount of lubricant supplied from the center
spray nozzles.
(4) Equipment for supplying a lubricant for rolling mill
as set forth in (3), wherein the amount of lubricant
10 supplied from the side spray nozzles are up to 2 times
the amount of lubricant supplied from the center spray
nozzles.
[0021] (5) Equipment for supplying a lubricant for
rolling mill as set forth in any one of (1) to (4),
15 wherein the lubricant feed device can individually
control the amount of lubricant supplied from the spray
nozzles.
According to the above (5), it is possible to
individually control the amount of lubricant supplied
20 from the nozzles, and thus a suitable end rich
distribution pattern can be realized even when the width
of the flat shaped metal material differs for each
rolling chance.
(6) Equipment for supplying a lubricant for rolling mill
25 as set forth in (5), wherein when divided into spray
nozzle groups comprised of adjoining spray nozzles, a
spray nozzle interval in at least one spray nozzle group
differs from the spray nozzle intervals in the other
spray nozzle groups.
30 (7) Equipment for supplying a lubricant for rolling mill
as set forth in (5), wherein the plurality of spray
nozzles are comprised of a plurality of roll end spray
nozzles which supply a lubricant to end regions of the
rolling roll and a plurality of roll center spray nozzles
35 which supply a lubricant to a center region of the roll
and wherein an interval between the roll end spray
nozzles and an interval between the roll center spray
nozzles differ.
[00221 (8) Equipment for supplying a lubricant for
rolling mill as set forth in (7), wherein the interval
between the roll center spray nozzles is broader than the
5 interval between the roll end spray nozzles.
(9) Equipment for supplying a lubricant for rolling mill
as set forth in (8), wherein the interval between the
roll center spray nozzles is not less than 105 times the
interval between the roll end spray nozzles.
10 (10) Equipment for supplying a lubricant for rolling mill
as set forth in any one of (5) to (9), wherein the
lubricant feed device provides the same number of pump
devices as the number of spray nozzles and each pump
device feeds a lubricant to a single corresponding spray
15 nozzle.
[00231 (11) Equipment for supplying a lubricant for
rolling mill as set forth in any one of (5) to (9),
wherein the lubricant feed device provides the same
number of flow regulators as the number of spray nozzles
20 and each flow regulator controls the amount of lubricant
fed to a single corresponding spray nozzle.
(12) Equipment for supplying a lubricant for rolling mill
as set forth in any one of (5) to (11), wherein the
lubricant feed device individually controls the amount of
25 lubricant supplied from the spray nozzles for each spray
nozzle in accordance with a parameter relating to the
surface of the rolling roll.
According to the above (12), it is possible to
monitor the state of the roll surface (for example,
30 amount of wear or roughness) and control the amount of
lubricant individually in accordance with the situation
so as to more efficiently avoid uneven wear and roughness
of the roll.
(13) Equipment for supplying a lubricant for rolling mill
35 as set forth in (12), wherein the parameter relating to
the surface of the rolling roll is the amount of wear of
the rolling roll and wherein the lubricant feed devices
increase the amount of lubricant supplied to regions of
the rolling roll with relatively large amounts of wear
compared with regions of the rolling roll with relatively
small amounts of wear.
5 [00241 (14) Equipment for supplying a lubricant for
rolling mill as set forth in (12) or (13), wherein the
parameter relating to the surface of the rolling roll is
a surface roughness and wherein the lubricant feed
devices increase the amount of lubricant supplied to
10 regions,of the rolling roll with relatively large surface
roughnesses compared with regions of the rolling roll
with relatively small surface roughnesses.
(15) Equipment for supplying a lubricant for rolling mill
as set forth in any one of (1) to (14), wherein at least
15 part of the spray nozzles are internal mixing type spray
nozzles, the lubricant has a dynamic viscosity at 40°C of
60 to 800 cSt, the gas feed devices feed the spray
nozzles gas at 0005 MPa or more pressure, and the
lubricant feed devices feed the internal mixing type
20 spray nozzles a lubricant by a pressure of at least the
pressure of the gas in the mixing chambers of the spray
nozzles.
(16) Equipment for supplying a lubricant for rolling mill
as set forth in any one of (1) to (15), wherein at least
25 part of the spray nozzles are external mixing type spray
nozzles, the lubricant has a dynamic viscosity at 40°C of
6.0 to 800 cSt, the gas feed device feeds the spray
nozzles gas at 0005 MPa or more pressure, and the
lubricant feed devices feed the external mixing type
30 spray nozzles a lubricant by a pressure of at least 0001
MPa and less than the feed pressure of gas to the spray
nozzles.
[0025] (17) Equipment for supplying a lubricant for
rolling mill as set forth in (15) or (16), wherein the
35 spray nozzles are comprised of internal mixing type spray
nozzles and external mixing type spray nozzles, internal
mixing type spray nozzles are arranged at the center in
1.0 -
the width direction of the flat shaped metal material,
and external mixing type spray nozzles are arranged at
the outsides,
(18) Equipment for supplying a lubricant for rolling mill
5 as set forth in any one of (1) to (17), wherein the spray
nozzles have water spray parts which spray water so that
water films are formed at outsides of spray cones of
lubricant and gas from the spray nozzles.
[0026 ] (19) A method of supplying a lubricant to a
10 surface of a rolling roll, comprising: spraying a
lubricant from a plurality of spray nozzles toward the
rolling roll together with a gas in a particulate or
atomized state, wherein when designating the spray
nozzles which are positioned at the both ends among the
15 spray nozzles which supply a lubricant to the parts of
the rolling roll corresponding to the width of a flat
shaped metal material as the side spray nozzles and
designating the spray nozzles which are positioned at the
center as the center spray nozzles, at the spraying from
20 the spray nozzles, the amount of lubricant supplied from
the side spray nozzles is increased over the amount of
lubricant supplied from the center spray nozzles and the
amount of lubricant supplied from the spray nozzles
between these side spray nozzles and center spray nozzles
25 are made not more than the amount of lubricant ,_>upplied
from the side spray nozzles and not less than the amount
of lubricant supplied from the center spray nozzles.
(20) A method of supplying a lubricant to a rolling mill
as set forth in (19), wherein the amount of lubricant
30 supplied from the spray nozzles between these side spray
nozzles and center spray nozzles are made gradually
smaller from the sides toward the center of the rolling
roll.
(21) A method of supplying a lubricant to a rolling mill
35 as set forth in (19) or (20), wherein the amount of
lubricant supplied from the side spray nozzles is made up
to 5 times the amount of lubricant supplied from the
11
center spray nozzles.
[00271 (22) A method of supplying a lubricant to a
rolling mill as set forth in (21), wherein the amount of
lubricant supplied from the side spray nozzles is made up
5 to 2 times the amount of lubricant supplied from the
center spray nozzles.
(23) A method of supplying a lubricant to a rolling mill
as set forth in any one of (19) to (22), wherein the
amount of lubricant supplied from the spray nozzles can
10 be controlled for each spray nozzle in accordance with a
parameter relating to the surface of the rolling roll.
(24) A method of supplying a lubricant to a rolling mill
as set forth in (23), wherein the parameter relating to
the surface of the rolling roll is the amount of wear of
15 the rolling roll and wherein the amount of lubricant
supplied to regions of the rolling roll with relatively
large amounts of wear is increased compared with regions
of the rolling roll with relatively small amounts of
wear.
20 [0028] (25) A method of supplying a lubricant to a
rolling mill as set forth in (23) or (24), wherein the
parameter relating to the surface of the rolling roll is
a surface roughness and wherein the amount of lubricant
supplied to regions of the rolling roll with relatively
25 large surface roughnesses is increased compared with
regions of the rolling roll with relatively small surface
roughnesses°
(26) A method of supplying a lubricant to a rolling mill
as set forth in any one of (23) to (25), wherein each
30 spray nozzle is fed with a lubricant from a pump device
for the spray nozzle and the amount of lubricant fed from
the spray nozzles are controlled by changing the outputs
of the pump devices corresponding to the spray nozzles.
(27) A method of supplying a lubricant to a rolling mill
35 as set forth in any one of (23) to (25), wherein each
spray nozzle is fed with a lubricant through a flow
regulator for the spray nozzle and the amount of
12 _r
lubricant fed from the spray nozzles are controlled by
changing the opening degrees of the flow regulators
corresponding to the spray nozzles.
[0029] (28) A method of supplying a lubricant to a
5 rolling mill as set forth in any one of (19) to (27),
wherein at least part of the spray nozzles are internal
mixing type spray nozzles, the lubricant has a dynamic
viscosity at 40°C of 60 to 800 cSt, and the gas is fed to
the internal mixing type spray nozzles at 0.05 MPa or
10 more pressure and the lubricant is fed at a pressure of
not less than the pressure of the gas in the mixing
chambers of the spray nozzles.
(29) A method of supplying a lubricant to a rolling mill
as set forth in any one of (19) to (28), wherein at least
15 part of the spray nozzles are external mixing type spray
nozzles, the lubricant has a dynamic viscosity at 40°C of
60 to 800 cSt, and the gas is fed to the external mixing
type spray nozzles at 0®05 MPa or more pressure and the
lubricant is fed at a pressure of not less than 0.01 MPa
20 and not more than the feed pressure of gas to the spray
nozzles.
(30) A method of supplying a lubricant to a rolling mill
as set forth in any one of (19) to (29), further
comprising I.orming water films at outsides of :;pry cones
25 of a lubricant and gas from the spray nozzles.
Advantageous Effects of Invention
[0030 ] According to the equipment for supplying a
lubricant and methods of supplying a lubricant according
30 to the present invention, the amount of lubricant
supplied from the spray nozzles which are positioned
close to the both ends among the plurality of spray
nozzles which are arranged in the axial direction of the
rolling roll are made than the amount of
35 lubricant supplied from the spray nozzles which are
positioned near the center. Due to this, the amount of
lubricant supplied near the both ends of the rolling roll
13
where wear and roughness occur most easily become greater
and wear and roughness of the rolling roll at those
regions are suppressed. As a result, the occurrence of
uneven wear and roughness at the rolling roll in the
5 axial direction of the rolling roll are suppressed. For
this reason, there is the effect of prolongation of the
roll exchange period and the avoidance of product defects
due to sporadic formation of flaws of course while
stabilization of the roll profile is also contributed to,
10 so it is also possible to obtain the effect of
improvement of precision in control of the thickness and
control of the shape of flat shaped metal materials.
Below, the present invention will be able to be
understood much more clearly from the attached drawings
15 and the preferred embodiments of the present invention.
Brief Description of Drawings
FIG. 1 is a schematic view which shows a
configuration of equipment for supplying a lubricant
20 (water injection method) according to the prior art.
FIG. 2 is a schematic view which shows a
configuration of equipment for supplying a lubricant
according to the present invention.
FIG. 3 is a cross-sectional view of an internal
25 mixing type two-fluid spray nozzle which is used in the
present inventions
FIG. 4 is a cross-sectional view of an external
mixing type two-fluid spray nozzle which is used in the
present invention.
30 FIG. 5 is a schematic view which shows the
arrangement of spray nozzles in the equipment for
supplying a lubricant according to the present invention.
FIG. 6(A) and FIG. 6(B) are schematic views which
show a lubricant feed rate from spray nozzles in the
35 equipment for supplying a lubricant according to the
present invention.
FIG. 7 is a view which shows a state of spraying a
4
lubricant from a spray nozzle in a particulate state or
an. atomized state.
FIG. 8(A) and FIG. 8(B) are views which
schematically show a water film forming system.
5
Description of Embodiments
[0032] Below, referring to the figures, embodiments of
the present invention will be explained in detail. Note
that, in the following explanation, similar constituent
10 elements are assigned the same reference numerals.
[ 0033 ] One example of the configuration of the
equipment for supplying a lubricant according to the
present invention is shown in FIG. 2. As shown in this
figure, the equipment for supplying a lubricant according
15 to the present invention is provided with a plurality of
spray nozzles la and 1b, pump devices 3 which are
connected to these spray nozzles la and lb and feed a
lubricant to these spray nozzles la and 1b, and a
lubricant storage tank 4 which stores the lubricant. The
20 lubricant which is stored inside the lubricant storage
tank 4 is fed by the pump devices 3 to the spray nozzles,
la and lb.
[0034] As shown in FIG. 2, the same number of pump
devices 3 as the number of spray nozzles are provided.
25 One pump device 3 is connected to each of the spray
nozzles la and lb. Due to this, the amount of the
lubricant fed to the spray nozzles la and lb can be set
in advance for the spray nozzles la and lb and can be
individually adjusted during rolling for each of the
30 spray nozzles la and lb.
[0035 ] Here, as a pump device 3, any type of pump
device may be used so long as being equipped with a
constant rate discharge mechanism. For example, a
precision gear pump, trochoid pump, rocking type pump,
35 plunger pump, etc. may be used. The "pump device which
has a constant discharge function" referred to here is
one where the precision in setting the amount of supplied
- 15
lubricant is kept to a fluctuation of not more than 20%
of the set value and has the function of enabling change
of the amount of supplied lubricant at a speed of 001
cc/min or more per second.
5 [0036] Note that, as the pump device 3, a
configuration where two or more pump devices are
connected and set in parallel and made to appear to
function as a single pump device is also possible. By
doing this, the range of setting of the amount of
10 supplied lubricant can be easily broadened. For the
constant discharge function in the case of setting a
plurality of pump devices in parallel, the individual
pump devices which are set in parallel should have that
constant discharge function.
15 [00371 To set and/or adjust the amount of the
lubricant supplied to any values for the spray nozzles
all at once, there is the method of simultaneously
interlockingly operating electrical devices for adjusting
the constant discharge functions of the pumps and the
20 method of using a pump device which is provided with a
plurality of pump mechanisms while being a single pump
device, such as a planetary multiport gear pump. In the
latter case, the number of the pump mechanisms which are
provided in the pump device corresponds to the number of
25 pump devices 3. For example, in a six-port planetary type
gear pump, this is deemed as a device provided with six
pump devices 3. For this reason, while in actuality a
single pump device, it is deemed as six pump devices 3,
so this is one aspect of the present invention.
30 [0038j Between the spray nozzles la and lb and the
pump devices 3, lubricant switches 2 may be provided for
turning the supply of a lubricant ON/OFF. This enables
the supply of a lubricant to be turned ON/OFF at suitable
timings.
35 Note that, the lubricant switches 2 are not
essential. However, in a normal rolling mill, the pump
devices 3 and spray nozzles 1 are almost always set
16
separated by distances of at least I meter or more. Under
such a situation, if just turning the pump devices 3
ON/OFF to turn the supply of a lubricant ON/OFF,
sometimes it is not possible to perform the lubricated
5 rolling at a suitable timing. In such a case, it is
effective to introduce lubricant switches 2. On the other
hand, if the pump devices 3 and the spray nozzles 1 are
within 1 meter of each other, there is little need to
provide the lubricant switches 20
10 [0039] When using a switching valve for a lubricant
switch 2, at the lubricant ON setting, that is, when
spraying a lubricant from the spray nozzle, the lubricant
is discharged to the spray nozzle. On the other hand, at
the lubricant OFF setting, that is, when not spraying a
15 lubricant from the spray nozzle, the lubricant passes
through the route which is shown by the broken lines in
FIG. 2 and is returned to the lubricant storage tank 4.
It may also be returned to the lubricant pipe between the
pump device 3 and the lubricant storage tank 4.
20 [0040] Further, the equipment for supplying a
lubricant according to the present invention is provided,
with a noncombustible gas source '5 which is connected to
the spray nozzles la and lb and feeds air or a
noncombustible gas or other gas to these spray nozzles la
25 and lb. In particular, in the present embodiment, the
equipment for supplying a lubricant is provided with only
one noncombustible gas source 5. Pipes are branched from
this single noncombustible gas source 5 whereby gas is
fed to the spray nozzles la and lb.
30 [0041 ] Between the spray nozzles la and lb and the
noncombustible gas source 5, as shown in FIG. 2, a gas
switch 6 may be installed for turning the feed of gas
ON/OFF. This enables the feed of gas to the spray nozzles
to be turned ON/OFF in accordance with need.
35 [0042] Note that, in the example which is shown in
FIG. 2, the gas switch 6 is installed right after the
noncombustible gas source 5. Between the gas switch 6 and
17
the spray nozzles la and 1b, piping is branched into
exactly the number of pipes corresponding to the spray
nozzles. Due to this, the individual spray nozzles can be
fed with gas. However, if individually turning the feed
5 of gas ON/OFF for each spray nozzle, it is sufficient to
branch the piping between the gas switch 6 and the
noncombustible gas source 5 into a number of branches
corresponding to the number of spray nozzles and set a
number of gas switches 6 corresponding to the number of
10 spray nozzles in the branched pipes.
[0043] As the gas, use of the industrially frequently
used air or nitrogen is preferable cost wise, anything
may be used as long as it is noncombustible. Argon or
helium are also possible.
15 The noncombustible gas source 5 is provided with the
function of adjusting the pressure of the gas which is
fed to the spray nozzles. Due to this, the spray pressure
of the gas from the spray nozzles can be adjusted to the
suitable pressure. Note that, in the example which is
20 shown in FIG. 2, the spray nozzles are fed with gas of
the same pressure. However, if desiring to individually
change the spray pressure for each'spray nozzle, it is
possible to introduce pressure adjusting devices inside
the branched pipes so as to set/adjust the feed pressures
25 of the gas to the spray nozzles.
[0044 ] The spray nozzles la and lb spray a lubricant
which is fed from the pump devices 3 together with gas
which is fed from the noncombustible gas source 5 toward
the rolling roll 20 (see FIG. 5) in a particulate or
30 atomized state. As such spray nozzles la and lb, internal
mixing type two-fluid spray nozzles la such as shown in
FIG. 3 and external mixing type two-fluid spray nozzles
lb such as shown in FIG. 4 are used.
[004 ] In an internal mixing type two-fluid spray
35 nozzle la, as shown in FIG. 3, the inside of the spray
nozzle is provided with a chamber (mixing chamber) 18 for
mixing the gas 11 and the lubricant 12. On the other
i8
hand, in an external mixing type two-fluid spray nozzle
lb, as shown in FIG. 4, such a chamber is not provided.
The gas 11 and the lubricant 12 are mixed outside of the
spray nozzle lb. In the present embodiment, part of the
5 spray nozzles of the plurality of spray nozzles are made
internal mixing type two-fluid spray nozzles la, while
the remainder are made external mixing type two-fluid
spray nozzles lb. However, it is also possible to
configure all of the spray nozzles as just either spray
10 nozzles of internal mixing type two-fluid spray nozzles
and external mixing type two-fluid spray nozzles.
[0046] FIG. 5 shows the arrangement of the spray
nozzles la and lb in the equipment for supplying a
lubricant of the present invention. As will be understood
15 from FIG. 5, the spray nozzles la and lb are arranged in
the axial direction X of the rolling roll 20. In
particular, in the illustrated embodiment, the spray
nozzles la and lb are arranged in a line in the axial
direction X of the rolling roll 20, but these spray
20 nozzles la and lb may also be arranged offset in the
direction perpendicular to the axial direction X of the
rolling roll 200
[0047] Further, as will be understood from FIG. 5, the
intervals of arrangement between the spray nozzles la and
25 lb differ. In the illustrated embodiment, the interval
between the spray nozzles la which spray a lubricant to
the center region C which is positioned at the center in
the axial direction X of the rolling roll 20 (center
spray nozzles) is broader than the interval between the
30 spray'nozzles lb which spray a lubricant to the end
regions E which are positioned at the two ends in the
axial direction X of the rolling roll 20 (end spray
nozzles).
[0048] In the illustrated example, the width of the
35 rolling roll 20 (length in the axial direction X) is 2000
mm, the center region C is a region of 1200 mm at the
center of the rolling roll, and the end regions E are
-- 1.9
regions of 400 mm from. the ends of the rolling roll 20.
The interval between spray nozzles la which spray a
lubricant at the center region C is made 300 mm, while
the interval between spray nozzles lb which spray a
5 lubricant at the end regions E is made 100 mm. Therefore,
in the present embodiment, the interval between spray
nozzles la which spray a lubricant at the center region C
is three times the interval between spray nozzles lb
which spray a lubricant at the end regions E. Note that,
10 the ratio of the intervals is preferably 105 or more.
[0049] Further, in the illustrated embodiment, the
spray nozzles la which spray a lubricant at the center
region C of the rolling roll 20 are formed by internal
mixing type two-fluid spray nozzles la, while the spray
15 nozzles lb which spray a lubricant at the end regions E
of the rolling roll 20 are formed by external mixing type
two--fluid spray nozzles lb.
[0050] Note that, in the above embodiment, the nozzle
interval is changed between the spray nozzles which spray
20 a lubricant at the center region C and the spray nozzles
which spray a lubricant at the end regions E. However,
the nozzle interval does not necessarily have to be
changed in two stages in this way. It may also be changed
in three stages or more stages. Alternatively, all nozzle
25 intervals may be made different. If changing the way of
looking at this, in the present invention, when dividing
all of the spray nozzles into groups of spray nozzles
comprised of adjoining spray nozzles, it can be said that
the spray nozzles are arranged so that the nozzle
30 interval in at least one spray nozzle group differs from
the nozzle intervals in the other spray nozzle groups.
[0051 ] Further, in the above example, the center
region C is the center 1200 mm region of the rolling
roll, and the end regions E are the regions of 400 mm
35 from the ends of the rolling roll 20. However, the
relationship between the center region C and the end
regions E does not necessarily have to be such a
20
relationship. It is also possible to make the center
region C the center 800 mm of the rolling roll and make
the end regions E the regions of 800 mm from the ends of
the rolling roll 20 or make other various relationships.
5 [0052] In addition, it is also possible to change the
boundaries of the center region and the end regions in
accordance with the width of the metal material which is
being rolled. For example, in one region in the axial
direction of a rolling roll, a single spray nozzle having
10 a wide spray angle and a plurality of spray nozzles each
having a narrow spray angle are provided in multiple
stages. At this time, the region of the rolling roll
which can be fed with a lubricant from the single spray
nozzle having a wide spray angle is made the same as the
15 region of the rolling roll which can be fed with a
lubricant from the plurality of spray nozzles each having
a narrow spray angle. Due to this, it becomes possible to
select between supplying a lubricant to a certain region
of the rolling roll from a single spray nozzle having a
20 wide spray angle and supplying a lubricant from a
plurality of spray nozzles each having a narrow spray
angle.
000531 According to the present invention, the nozzle
interval of the spray nozzles lb which spray a lubricant
25 to the end regions E becomes smaller than the nozzle
interval of the spray nozzles la which spray a lubricant
to the center region C. For this reason, it is possible
to-finely adjust the regions of spraying a lubricant to
the rolling roll 20 in accordance with the width of the
30 flat shaped metal material (for example, steel sheet)
which is rolled by the rolling roll 20 (length of flat
shaped metal material in direction vertical to direction
of progression). Due to this, substantially no lubricant
is supplied any longer to the regions of the rolling roll
35 20 which are positioned outside from the two edges of the
flat shaped metal material, and thus the amount of
consumption of the lubricant can be kept down.
- 21 -
[0054] Further, in general, the roiling roll 20 is
more susceptible to wear and roughness at the end regions
E rather than the center region C. With respect to this,
in the present invention, the nozzle interval of the
5 spray nozzles lb which spray a lubricant to the end
regions E is made narrow, and thus it is possible to
finely control the spray of a lubricant to the end
regions E of the rolling roll 20.
[0055] Furthermore, in the present embodiment, for the
10 spray nozzles which spray a lubricant at the center
region C, internal mixing type two-fluid spray nozzles
are used, while for the spray nozzles which spray a
lubricant at the end regions E, external mixing type twofluid
spray nozzles are used. Here, internal mixing type
15 two-fluid spray nozzles are provided with mixing chambers
at the tips of the nozzles, and thus it is easy to change
the shapes of the injection ports of the spray nozzles
and use as flat nozzles is possible. Flat nozzles enable
broad widths of spray of a lubricant by single spray
20 nozzles. For this reason, it is preferable to use
internal mixing type two-fluid spray nozzles for the
spray nozzles which spray a lubricant to the center
region C.
[0056] Next , the method of supplying a lubricant in
25 equipment for supplying a lubricant which is configured
in this way will be explained.
In this regard, in rolling of a metal material, in
particular in hot rolling of steel sheet, uneven wear
occurs in the axial direction of the rolling roll. In
30 particular, when evenly coating the surface of a rolling
roll with a lubricant, the amount of wear tends to become
greater near ends in the axial direction of a rolling
roll rather than near the center in the axial direction.
[00571 Therefore, in the present invention, the amount
35 of lubricant supplied to the spray nozzles are set in
advance for each spray nozzle so that the amount of
lubricant supplied change near the center and near the
- 2 2
ends in the axial direction of a rolling .roll. FIG. 6(A)
and FIG. 6(B) are schematic views which show amount of
lubricant supplied from the spray nozzles in the
equipment for supplying a lubricant of the present
5 invention. FIG. 6(A) is a view which is similar to FIG. 5
and shows a rolling roll 20 and a plurality of spray
nozzles. In particular, the spray nozzles of FIG, 6(A)
are assigned numbers ascending from the left side to the
right side in the figure. In the illustrated example, the
10 leftmost side spray nozzle is the #1 nozzle, while the
rightmost side spray nozzle is the #12 nozzle. In
particular, in the present embodiment, the #1 nozzle to
the #4 nozzle and the #9 nozzle to the #12 nozzle are
external mixing type two-fluid spray nozzles, while the
15 #5 nozzle to the #8 nozzle are internal mixing type twofluid
spray nozzles.
[0058] Further, the broken lines in FIG. 6(A) and FIG.
6(B) show the flat shaped metal material M which is
rolled by the rolling roll 20. Therefore, in the
20 illustrated example, a metal material with a width which
is somewhat narrower than the width of the rolling roll
20 is rolled by the rolling roll '20.
[0059] The graph of FIG. 6(B) shows the amount of
lubricant supplied to the surface of the rolling roll 20.
25 The abscissa in this graph indicates the position in the
axial direction of the rolling roll 20, while the
ordinate indicates the amount of lubricant which is
supplied per unit time per unit surface area of the
rolling roll 20 (Note that, in the Description, the
30 "amount of supplied lubricant" means the "amount of
lubricant which is supplied per unit surface area per
unit time").
[0060] As will be understood from FIG. 6(B), in the
present embodiment, the amount of lubricant supplied from
35 the #3 nozzle and the #10 nozzle are greater than the
amount of lubricant supplied from the #6 nozzle and the
#7 nozzle. Further, the amount of lubricant supplied from
-- 2 3
the spray nozzles between the #3 nozzle and the #6 nozzle
(that is, the #4 nozzle and the #5 nozzle) are not more
than the amount of lubricant supplied from the #3 nozzle
and are not less than the amount of lubricant supplied
5 from the #6 nozzle. Further, the amount of lubricant
supplied from the spray nozzles between the #7 nozzle and
the #10 nozzle (that is, the #8 nozzle and the #9 nozzle)
are not less than the amount of lubricant supplied from
the #7 nozzle and are not more than the amount of
10 lubricant supplied from the #10 nozzle. In particular, in
the illustrated example, the amount of lubricant supplied
becomes gradually smaller from the #3 nozzle toward the
#6 nozzle and from the #10 nozzle toward the #7 nozzle.
[ 0061 1 Further, in the example which is shown in FIG.
15 6, the width of the metal material M is narrower to a
certain extent than the width of the rolling roll 20, and
thus the regions of the rolling roll 20 which are
supplied with a lubricant by the #1 nozzle, the #2
nozzle, the #11 nozzle, and the #12 nozzle (regions A and
20 B in the figure) do not bite into the metal material M
and do not roll the metal material M. Therefore, the
regions A and B of the rolling roll 20 do not have to be
supplied with a lubricant. For this reason, in the
illustrated example, a lubricant is not sprayed from the
25 #1 nozzle, 112 nozzle, #11 nozzle, and #12 nozzle. That
is, the lubricant switches 2 corresponding to the #1
nozzle, #2 nozzle, #11 nozzle, and #12 nozzle are turned
OFF (when lubricant switches 2 are not provided, outputs
of corresponding pump devices 3 are made zero).
30 [00621 Note that, when the width of the metal material
is broader than the width of the metal material M which
is shown in FIG. 6 and substantially the entire width of
the rolling roll 20 grasps and rolls the metal material,
a lubricant is sprayed from all of the spray nozzles. In
35 this case, the amount of lubricant supplied from the #1
nozzle and the #12 nozzle are made larger than the amount
of lubricant supplied from the #6 nozzle and #7 nozzle.
-- 24
Further, the amount of lubricant supplied of the spray
nozzles between the #1 nozzle and the #6 nozzle are made
not more than the amount of lubricant supplied from the
#1 nozzle and not less than the amount of lubricant
5 supplied from the #6 nozzle. Further, the amount of
lubricant supplied of the spray nozzles between the #7
nozzle and the #12 nozzle are made not less than the
amount of lubricant supplied from the #7 nozzle and not
more than the amount of lubricant supplied from the #12
10 nozzle.
[0063] Summarizing the above, in the present
invention, if designating, among the spray nozzles which
supply a lubricant to the part of the rolling roll
corresponding to the width of the metal material (in the
15 example of FIG. 6, part other than regions A and B) (in
the example of FIG. 6, the #3 nozzle to the #10 nozzle),
the spray nozzles which are positioned at the two ends
(in the example of FIG. 6, the #3 nozzle and the #10
nozzle) as the "side spray nozzles" and the spray nozzles
20 which are positioned at the center as the "center spray
nozzles" (in the example of FIG. 6, the #6 nozzle and the
#7 nozzle), the amount of lubricant supplied from the
side spray nozzles are made greater than the amount of
lubricant supplied from the center spray nozzles. In
25 addition, the amount of lubricant supplied from the spray
nozzles between these side spray nozzles and center spray
nozzles are made not more than the amount of lubricant
supplied from the side spray nozzles and not less than
the amount of lubricant supplied from the center spray
30 nozzles. Specifically, the amount of lubricant supplied
from the side spray nozzles are made not more than 5
times the amount of lubricant supplied from the ccnter
spray nozzles, preferably not more than 2 times, further,
not less than 1001 times, preferably not less than 1003
35 times. If a ratio less than 1001 times, the effect of the
surface roughness of the roll or the rolled steel
material will be felt, and thus no difference will appear
- 25 -
in the thickness of the lubricant film in the roll axial
direction, and the amount of lubricant supplied from the
spray nozzles between the side spray nozzles and the
center spray nozzles cannot be changed. If larger than 5
5 times, the lubricant will pool at the roll bite entry
side and the lubricant will flow in from the side spray
nozzles to the center spray nozzle supply region, and
thus the amount of lubricant supplied will not be able to
be changed as intended.
10 [0064] Alternatively, in the present invention, it is
also possible to supply a lubricant as explained below.
That is, when the width of the metal material is 1000 mm
or more, if designating, among the spray nozzles which
supply a lubricant to the part of the rolling roll which
15 corresponds to the width of the metal material M (part
other than regions A and B of FIG. 6) (in the example of
FIG. 6, the #3 nozzle to #10 nozzle), the spray nozzles
which supply a lubricant to the side regions of the
rolling roll which correspond to distances of 100 mm from
20 the ends of the metal material M as the "side spray
nozzles" and the spray nozzles which supply a lubricant
to the center region of the rolling roll which
corresponds to the 300 mm at the center of the metal
material as the "center spray nozzles", the amount of
25 lubricant supplied from the side spray nozzles are made
greater than the amount of lubricant supplied from the
center spray nozzles. In addition, the amount of
lubricant supplied from the spray nozzles between these
side spray nozzles and center spray nozzles are made not
30 more than the amount of lubricant supplied from the side
spray nozzles and not less than the amount of lubricant
supplied from the center spray nozzles.
[0065 ] Note that, in the above-mentioned example, the
amount of lubricant supplied to the spray nozzles la and
35 lb are set in advance for each of the spray nozzles la
and lb. However, the amount of lubricant supplied to the
spray nozzles la and lb may also be made individually
26
adjustable during rolling. In this case, the amount of
lubricant supplied to the individual spray nozzles la and
lb are adjusted by individually operating electrical
devices for adjustment of the constant rate discharge
5 functions of the pumps. These operations include
utilization of a computer control system to change the
amount of lubricant supplied during rolling in accordance
with changes in signals detecting the rolling speed,
rolling load, tension, and presence of material or some
10 other signals or manual adjustment of the amount of
lubricant supplied of certain specific spray nozzles. The
ability for any adjustment method or setting method to be
handled is a feature of the present invention. The
adjustment method or setting method differs depending on
15 the quality or rolling conditions of the steel material
produced by the rolling mill, and thus a method suitable
for the usage environment should be used for the
operation.
[00661 As the method of control of the amount of
20 lubricant supplied to the spray nozzles 1, it may be
considered to change the amount of lubricant supplied to
the spray nozzles 1 in accordance with the amount of wear
of the rolling roll 20. That is, it`may be considered to
increase by 5 to 90% or so the amount of lubricant
25 supplied to locations of the rolling roll 20 where wear
has greatly progressed compared with locations where wear
has not progressed.
[006`11 Specifically, a profile meter (not shown) etc.
is used to detect the profile of the rolling roll 20
30 during rolling. As a result, when dividing the surface of
the rolling roll 20 into a plurality of regions in the
axial direction, the amount of supplied lubricant is made
greater for a region where the amount of wear is larger
compared with other regions (region with relatively large
35 amount of wear) compared with a region where the amount
of wear is smaller compared with other regions (region
with relatively small amount of wear). By performing such
- 27
control, the amount of lubricant supplied from the spray
nozzles consequently become as shown in FIG. 6(B) and as
a result the amount of wear of the rolling roll 20 is
made uniform in the axial direction.
5 [00681 Alternatively, as the method of control of the
amount of lubricant supplied to the spray nozzles, it may
be considered to change the amount of lubricant supplied
to the spray nozzles in accordance with the surface
roughness of the rolling roll 20. Specifically, a surface
10 roughness detection device (not shown) or visual
inspection etc. may be used to detect the surface
roughness of the rolling roll 20. As a result, if
dividing the surface of the rolling roll 20 into a
plurality of regions in the axial direction, the amount
15 of supplied lubricant is made greater for a region with a
larger surface roughness compared with. other regions
(region with relatively large surface roughness) compared
with a region with a smaller surface roughness compared
with other regions (region with relatively small surface
20 roughness). By performing such control, it is possible to
suppress variation in the surface roughness of the
rolling roll 20 in the axial dire'ctiono
(00691 In this regard, in the equipment for supplying
lubricant of the present invention, a lubricant with a
25 dynamic
less is
example
viscosity at 40°C of 60 cSt or more and 800 cSt or
used. Specifically, as the lubricant, for
a mineral oil-based lubricant, an ester-based
lubricant, a lubricant comprised of these plus various
additives, and, in addition to organically based ones as
30 well,'a non-oil-type lubricant of a colloidal form etc.
may be used.
[00701 The reason for using a lubricant with a dynamic
r
viscosity at 40°C of 60 cSt or more is that if using a
lubricant with a dynamic viscosity of less than 60 cSt,
35 the deposition ability of the lubricant itself on the
roll will become smaller, and a fine particle size mist
component will increase when rendering the lubricant a
28
particulate or atomized state, and thus the amount which
mist without depositing on the roll will become greater
making efficient deposition difficult. On the other hand,
the reason for using a lubricant with a dynamic viscosity
5 at 40°C of 800 cSt or less is that if using a lubricant
with a dynamic viscosity larger than 800 cSt, the piping
resistance when feeding the lubricant to the spray
nozzles will become greater and smooth feed will not be
possible unless pumping by a large pressure, and thus
10 constantly and stably spraying a lubricant from the spray
nozzles will become difficult and intermittent spraying
may easily result. Therefore, it becomes difficult to
maintain a uniform state of deposition of lubricant on
the roll.
15 [0071] Here, FIG. 7 shows the state when spraying a
lubricant 16 rendered into a particulate or atomized
state from a spray nozzle 1 toward the surface of a
sprayed object, that is, a rolling roll 20.
[00721 To stably spray a lubricant with a dynamic
20 viscosity at 40°C of 60 cSt or more from the spray nozzle
1 in the particulate or atomized state, the pressure of.
the gas has to be set at 0005 MPa or more. Further, the
surface of the rolling roll 20 to which the lubricant is
supplied always has roll cooling water remaining on it,
25 and therefore to effectively make the lubricant 16
deposit on the rolling roll, the residual roll cooling
water on the surface of the rolling roll 20 has to be
removed. For this, the gas which is sprayed from the
spray nozzles has to be sprayed by a pressure of at least
30 0005 MPa. If spraying the gas by a pressure of at least
0005 MPa, particulate or atomized lubricant 16 is
supplied to the surface of the rolling roll 20 and,
simultaneously, the residual roll cooling water is blown
away to thereby cause the lubricant to directly deposit
35 on the roll. Further, gas which is sprayed and fed by a
pressure of at least 0005 MPa also exhibits the effect of
making the deposited lubricant 17 uniformly even.
29
[00731 On the other hand, if spraying the gas together
with the lubricant by a pressure larger than 100 MPa gas,
even with a lubricant with a dynamic viscosity at 40°C of
800 cSt, the amount which does not deposit on the roll,
5 but is splattered to the surroundings increases and it
becomes difficult to make the intended amount of
lubricant deposit on the roll. Not only this, a lubricant
is made to deposit at places other than parts where the
lubricant is desired to be supplied. This obstructs
10 efficient usage of the lubricant and is uneconomical. Not
only that, this is not preferable from the viewpoint of
maintenance of a good lubricant usage environment.
Therefore, to make the lubricant stably deposit on the
rolling roll, the pressure of the gas has to be set to
15 1.0 MPa or less.
[0074] Further, when using an internal mixing type
two-fluid spray nozzle, the lubricant and gas are
coexistent in the mixing chamber inside of the spray
nozzle. For this reason, if the pressure when feeding
20 lubricant to a spray nozzle is lower than the pressure of
the gas in the mixing chamber inside the spray nozzle, it
will becomes difficult to stably'feed lubrication to the
mixing chamber inside of the spray nozzle without delay
and in some cases the gas will flow back through the
25 lubricant piping.
[0075] Therefore, in an internal mixing type two-fluid
spray nozzle, to spray a lubricant to a roll while mixing
it with a gas in a mixing chamber in the spray nozzle,
the pressure at the time of feed of the lubricant to the
30 spray nozzle has to be increased to not less than the
pressure of the gas inside of the mixing chamber. Note
that, the "pressure of the gas inside of the mixiiig
chamber of the spray nozzle" is the pressure which acts
inside of the lubricant piping near the entrance of the
35 lubricant at the spray nozzle when not discharging a
lubricant to the spray nozzle, but only feeding gas to
the spray nozzle. The pressure inside the mixing chamber
30
depends on the size of the spray ports and other aspects
of the structure of the spray nozzle and the original
pressure of the applied gas source (pressure inside of
piping of gas).
5 [0076] Further, to continuously stably feed spray
nozzles with a lubricant having a dynamic viscosity of
the lubricant at 40°C of 60 cSt or more to not more than
800 cSt, while the required pressure changes depending on
the piping configuration and length, inside diameter,
10 etc. of the lubrication equipment, a pressure of at least
0001 MPa has to be applied. If not, piping clogging etc.
will occur and stable feed will become difficult::. The
higher the pressure at the time of feeding the lubricant
becomes, the more difficult it becomes for piping
15 clogging to occur. Therefore, the pressure inside the
lubricant piping when pumping a lubricant to the spray
nozzle is preferably at least 0001 MPa,
[0077] On the other hand, for feed by an extremely
high pressure, a large capacity pump device becomes
20 necessary. Also, the pressure resistance ability of the
piping also has to be raised and the equipment cost
therefore becomes expensive. For'this reason, the
pressure at the time of feed of the lubricant is
preferably kept down to 3 MPa or less. If considering
25 these, the pressure at the time of feed of the lubricant
is preferably not less than 0005 MPa and not more than 3
MPa,
[0078] On the other hand, an external mixing type twofluid
spray nozzle differs from an internal mixing type
30 in that there is no chamber for mixing a lubricant and
gas inside the spray nozzle and in that spray nozzle a
stream of sprayed lubricant and a stream of sprayed gas
are made to collide right outside of the spray ports so
as to spray and supply a lubricant in a particulate or
35 atomized state on to an object to be sprayed.
[0079 ] Therefore, inside of an external mixing type
two-fluid spray nozzle, the flow path of the lubricant
and the flow path of the gas are independent from each
other, and thus the pressure and other conditions at the
time of feeding a lubricant and gas to the spray nozzles
almost never affect each other. For this reason, when a
5 lubricant of the above such dynamic viscosity is used, as
explained above, from the viewpoints of prevention of
piping clogging etc. and keeping down capital costs, a
pump device 3 should be used to pump a lubricant to a
spray nozzle by a pressure of at least 0.01 MPa to 3 MPa.
10 [0080] However, if feeding a lubricant to the spray
nozzles by a pressure higher than the pressure of the gas
and spraying the lubricant from the spray nozzles in this
way, the pressure of the gas will be insufficient and the
lubricant will be sprayed from the spray nozzles in a
15 state made particularly fluid like without forming a
particulate or atomized state. This phenomenon
particularly easily occurs in a lubricant with a range of
dynamic viscosity of the lubricant at 40°C of 60 to 800
cSto Therefore, when using external mixing type two-fluid
20 spray nozzles for spraying, the lubricant is pumped by a
pressure which is smaller than the feed pressure of the
gas to the spray nozzles.
[0081] Note that, in the present embodiment, the same
number of pump devices 3 as the number of spray nozzles
25 are provided and the amount of lubricant supplied to the
spray nozzles are controlled. However, it is also
possible to reduce the number of pump devices from the
number of spray nozzles and, for example, use a single
pump device and provide the same number of flow
30 regulators as the number of spray nozzles. In this case,
the amount of lubricant supplied to the spray nozzles are
controlled by the flow regulators.
[0082] Further, in the above embodiment, internal
mixing type -two-fluid spray nozzles and external mixing
35 type two--fluid spray nozzles are used. However, it is not
absolutely necessary to use both internal mixing type
two-fluid spray nozzles and external mixing type two32
fluid spray nozzles. It is also possible to use just one
type. The type of two-fluid spray nozzles to be used is
suitably selected in accordance with the conditions and
location for supply of the lubricant.
5 (00831 Note that, for selection of use of these twofluid
spray nozzles, since internal mixing type two-fluid
spray nozzles are provided with mixing chambers at the
tips of the nozzles, changing the shape of the spray
ports of the spray nozzles is easy, and thus these are
10 comparatively used as flat nozzles. A flat nozzle enables
a broad range of spraying of a lubricant to be obtained
by a single spray nozzle, and thus such a spray nozzle is
often suitable for supplying a lubricant to a rolling
roll for steel sheet/strip. As opposed to this, an
15 external mixing type two-fluid spray nozzle often has a
circular shape of spray port of the spray nozzle, and
thus is suitable for uniform spraying and is often used
as a round nozzle.
[0084] Next, a second embodiment of the present
20 invention will be explained. In this regard, when a large
amount of water has been applied to the roll surface to
which the lubricant is being supplied or the lubricant
has to be supplied in the midst of flying scale etc., the
gas has to be sprayed by a pressure of 100 MPa or more.
25 At such a time, the amount of the sprayed lubricant which
splatters to the surroundings without depositing on the
roll, that is, the so-called floating mist, becomes
greater. Not only is this inefficient, but it also
invites deterioration of the unit consumption of a
30 lubricant.
(00851 Therefore, in the second embodiment, the spray
cones which are formed when spraying a lubricant are
covered by water films at their surroundings. FIG. 8(A)
is a side view which schematically shows a water film
35 forming system, while FIG. 8(B) is a plan view which
schematically shows a water film forming system. FIG.
8(B) shows only the surroundings near the other end of
- 33
the rolling roll 20.
[00861 As will be understood from FIG. 8(A) and FIG.
8(B), the water film forming system 25 is provided with a
plurality of water spray nozzles 26 (26a, 26b, 26c) which
5 spray water so as to form water films. The water spray
nozzles 26 are provided with a nozzle 26a which forms a
water film above spray cones from the spray nozzles of
lubricant, a nozzle 26b which forms a water film below
the spray cones from the spray nozzles of lubricant, and
10 nozzles 26c which form a water film at the sides
(outsides) of the spray cones from the lubricant spray
nozzles at the both ends (FIG. 8(B) shows only one). The
amount of water which is sprayed changes depending on the
spray conditions of the lubricant, but it is preferable
15 to form the water films by a flow rate of at least 1000
cc per minute. By forming water films around the spray
cones from lubricant spray nozzles in this way, it is
possible to greatly reduce the amount of splatter due to
the floating mist.
20 [008 7] Note that, as means for forming the water films
around the spray cones, in addition to the abovementioned
method of spraying water by installing a
nozzles for formation of water films in addition to the
two-fluid spray nozzles which spray a lubricant in the
25 above way, the method may be considered of att,-iching sub
nozzles for forming water films at the outside of the
two-fluid spray nozzle and forming water films around the
spray cones of the lubricant right after nozzle spraying.
Any method may be used so long as able to form water
30 films=around spray cones from lubricant spray nozzles.
Examples
[0088] The amount of supplied lubricant was controlled
at a fifth stand of a hot final rolling mill comprised of
35 a first stand to a seventh stand. The steel material was
rolled from the first stand in order to the seventh stand
while being rolled. For the rolled steel material, a
34
general low carbon steel was used. It was rolled from a
thickness at the first. stand entry side of 32 mm to a
thickness at the seventh stand exit side of 2.3 mm. As
the rolled steel material, one with a width of 1820 mm to
5 1940 mm was used.
[0089] A header comprised of spray nozzles aligned in
the axial direction of the rolling roll was installed and
gear pumps enabling the amount of supplied lubricant to
be individually set were connected to the spray nozzles.
10 At the header, spray nozzles were arranged such as shown
in FIG. 5. For the rolling roll, a roll which was
measured for roll profile after polishing was used. For
the lubricant, one having a dynamic viscosity at 40°C of
230 cSt was used. For the gas for injection feed use, air
15 was used. The supply of lubricant was started
simultaneously with the rolled material being gripped by
the rolling mill and was ended simultaneously with the
steel material being withdrawn from the fifth stand.
[0090] First, lubrication rolling was performed under
20 the lubricant supply conditions which are shown in the
conditions of the following Table 1 so as to roll about
245 tons. After that, the roll was pulled out and the
roll profile was measured to calculate the average depth
of wear for each lubricant supply region of each spray
25 nozzle and the average depth of wear for the roll as a
whole. The ratio of the average roll wear depth at the
lubricant supply region of each spray nozzle to the roll
as a whole was calculated and the ratio was multiplied
with the coefficient a (in the present embodiment, 100)
30 and the initial amount of lubricant supplied from each
spray nozzle (condition of Table 1) to obtain a value
'which was then used as the amount of supplied lubricant
at the time of the next rolling operation. After that,
the roll was reinstalled and lubricated rolling was
35 continued until a predetermined rolling amount.
35 -
Table 1
Air pressure (MPa) Internal mixing type 0.3
External mixing type 0.4
Lubricant pressure (MPa) Internal mixing type 0.4
External mixing type 0.05
Amount of lubricant per Internal mixing type 1
m2 of rolling roll
surface area (cc/m2)
External mixing type 1
[0091] The results when measuring the difference
between the maximum average wear depth and minimum
5 average wear depth in the roll width direction when
repeating roll profile measurement and correction of the
amount of supplied lubricant in this way are shown in
Table 2. By repeating this lubrication rolling, it is
possible to reduced the difference in wear of the roll
10 profile and possible to roll in a state close to the
initial roll profile. Note that, in Table 2, the "ratio"
expresses the ratio of the amount of lubricant supplied
from the side spray nozzles to the amount of lubricant
supplied from the center spray nozzle.
Table 2
Rolling Item Nozzle no. Over Wear Ratio
am't 1 2 3 4 5 6 7 8 9 10 11 12 all depth
(tons ) Lubricant spray width (mm) 100 100 100 100 300 300 300 300 100 100 100 100 2000 difference
0 Average wear depth ( um) 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1.00
Amount of supplied lubricant
(cc/m2)
1 1 1 1 1 1 1 1 1 1 1 1 -
245 Average wear depth ( um) 5.4 5 . 6 4.8 4 3.8 3.2 3.4 3.4 4.4 4.8 5.8 5.4 4.08 2.6 1.81
Amount of supplied lubricant
(cc/m2)
1.32 1.37 1.18 0 . 98 0.93 0.78 0.83 0.83 1.08 1.18 1.42 1.32 -
493 Average wear depth ( um) 9.2 9.4 8.6 8 . 4 8.2 7.6 8 7.8 1 8.6 9 9.4 9.2 8.33 1.8 1.24
Amount of supplied lubricant
(cc/m2)
1.10 1 . 13 1.03 1 . 01 0.98 0.91 0.96 0 . 94 1.03 1.08 1.13 1.10 -
698 Average wear depth (um) 12 . 6 12.2 12 12 .2 12 11 .6 11.8 11.8 12.2 12.4 12.8 12.6 12 . 03 1.2 1.10
Amount of supplied lubricant
(cc/m2)
1.05 1.01 1.00 1.01 1.00 0.96 0.98 0.98 1.01 1.03 1.06 1.05 -
1103 Average wear depth (um) 16.4 1 16.4 16 15.8 15 . 6 15.8 15 . 6 15.6 16 16.2 1.64 1.64 15,87 0,8 1.05
Amount of supplied lubricant
(cc/m2)
1.03 1 . 03 1.01 1.00 0.98 1 . 00 0.98 0 . 98 1.01 1.02 1.03 1.03 -
-- 3 7
Note that, the present invention was described in detail
based on specific embodiments, but a person skilled in
the art could make various changes, modifications, etc.
5
without departing from the claims and concept of the
present invention.
Reference Signs List
[00921 1: lubricant supply nozzle (here, two-fluid
10
gas-liquid mixing and spraying type, gas atomization
method use)
5
la: internal mixing type two-fluid spray nozzle
ib: external mixing type two-fluid spray nozzle
1': lubricant supply nozzle (single-fluid type,
injection method use)
2: lubricant switch
water
0
3: pump device (lubricant discharge use)
3': pump device (water discharge use)
4: lubricant storage tank
5: noncombustible gas source
6: gas switch
5
8: injector (water and lubricant mixer)
9: water source
10: device for turning feed of water ON/OFF
11: gas
12: pumped lubricant
0
16: particulate or atomized lubricant
17: lubricant deposited on sprayed object
18: mixing chamber
20: rolling roll
M: metal material (rolled material)
X: axis
3 8 -

CLAIMS
Claim 1
Equipment for supplying a lubricant for a rolling
roll of a rolling mill for a flat shaped metal material,
5 comprising:
a plurality of spray nozzles which are arranged
in an axial direction of said rolling roll and which
spray a lubricant toward said rolling roll -together with
a gas in a particulate or atomized state;
10 a lubricant feed device which feeds a lubricant
to the spray nozzles; and
a gas feed device which feeds a gas to the
spray nozzles,
wherein when designating the spray nozzles
15 which are positioned at the both ends among the spray
nozzles which supply a lubricant to the parts of said
rolling roll corresponding to the width of said flat
shaped metal material as the side spray nozzles and
designating the spray nozzles which are positioned at the
20 center as the center spray nozzles, the amount of
lubricant supplied from the side spray nozzles are larger
than the amount of lubricant supplied from the center
spray nozzles and amount of the lubricant supplied from
the spray nozzles between these side spray nozzles and
25 center spray nozzles are not more than the amount of
lubricant supplied from said side spray nozzles and not
less than the amount of lubricant supplied from said
center spray nozzles.
Claim 2
30 Equipment for supplying a lubricant for rolling mill
as set forth in claim 1, wherein the amount of lubricant
supplied from the spray nozzles between these side spray
nozzles and center spray nozzles become smaller from the
sides toward the center of said rolling roll.
35 Claim 3
Equipment for supplying a lubricant for rolling mill
as set forth in claim 1, wherein the amount of lubricant
39
supplied from said side spray nozzles are up to 5 times
the amount of lubricant supplied from said center spray
nozzles.
Claim 4
5 Equipment for supplying a lubricant for rolling mill
as set forth in claim 1, wherein said lubricant feed
devices can individually control the amount of lubricant
supplied from the spray nozzles.
Claim 5
10 Equipment for supplying a lubricant for rolling mill
as set forth in claim 4, wherein said lubricant feed
devices individually control the amount of lubricant
supplied from each spray nozzle in accordance with a
parameter relating to the surface of the rolling roll.
15 Claim 6
Equipment for supplying a lubricant for rolling mill
as set forth in claim 5, wherein said parameter relating
to the surface of the rolling roll is the amount of wear
of the rolling roll and wherein said lubricant feed
20 devices increase the amount of supplied amount of
lubricant supplied to regions of the rolling roll with
relatively large amounts of wear compared with regions of
the rolling roll with relatively small amounts of wear.
Claim 7
25 Equipment for supplying a lubricant for rolling mill
as set forth in claim 1, wherein at least part of said
spray nozzles are internal mixing type spray nozzles,
said lubricant has a dynamic viscosity at 40°C of 60 to
800 cSt, said gas feed devices feeds a gas to said spray
30 nozzles at 0005 MPa or more pressure, and
said lubricant feed devices feeds a lubricant
to said internal mixing type spray nozzles at least at
the pressure of the gas in the mixing chambers of the
spray nozzles or more.
35 Claim 8
Equipment for supplying a lubricant for rolling mill
as set forth in claim 1, wherein at least part of said
40
spray nozzles are external mixing type spray nozzles,
said lubricant has a dynamic viscosity at 40°C of 60 to
800 cSt, said gas feed devices feeds a gas to said spray
nozzles at 0.05 MPa or more pressure, and
5 said lubricant feed devices feeds a lubricant
to said external mixing type spray nozzles at least. 0.01
MPa and less than the feed pressure of gas to the spray
nozzles.
Claim 9
10 Equipment for supplying a lubricant for rolling mill
as set forth in claim 7, wherein
said spray nozzles are comprised of internal
mixing type spray nozzles and external mixing type spray
nozzles,
15 internal mixing type spray nozzles are arranged
at the center in the width direction of said flat shaped
metal material, and external mixing type spray nozzles
are arranged at the outsides.
Claim 10
20 A method of supplying a lubricant to a surface of a
25
rolling roll, comprising:
spraying a lubricant from a plurality of spray
nozzles toward said rolling roll together with a gas in a
particulate or atomized state,
wherein when designating the spray nozzles
which are positioned at the both ends among the spray
nozzles which supply a lubricant to the parts of said
rolling roll corresponding to the width of said flat
shaped metal material as the side spray nozzles and
30 designating the spray nozzles which are positioned at the
center as the center spray nozzles, at the spraying from
the spray nozzles, the amount of lubricant supplied from
the side spray nozzles is increased over the amount of
lubricant supplied from the center spray nozzles and the
35 amount of lubricant supplied from the spray nozzles
between these side spray nozzles and center spray nozzles
are made not more than the amount of lubricant supplied
41
from said side spray nozzles and not less than the amount
of lubricant supplied from said center spray nozzles.
Claim 11
A method of supplying a lubricant to a rolling mill
5 as set forth in claim 10, wherein the amount of lubricant
supplied from the spray nozzles between these side spray
nozzles and center spray nozzles are made gradually
smaller from the sides toward the center of said rolling
roll.
10 Claim 12
A method of supplying a lubricant to a rolling mill
as set forth in claim 10, wherein the amount of lubricant
supplied from said side spray nozzles is made up to 5
times the amount of lubricant supplied from said center
15 spray nozzles.
Claim 13
A method of supplying a lubricant to a rolling mill
as set forth in claim 10, wherein the amount of lubricant
supplied from the spray nozzles can be controlled for
20 each spray nozzle in accordance with a parameter relating
to the surface of the rolling roll.
Claim 14
A method of supplying a lubricant to a rolling mill
as set forth in claim 13, wherein said parameter relating
25 to the surface of the rolling roll is the amount of wear
of the rolling roll and wherein the amount of supplied
lubricant to regions of the rolling roll with relatively
large amounts of wear is increased compared with regions
of the rolling roll with relatively small amounts of
30 wear.,
Claim 1.5
A method of supplying a lubricant to a rolling mill
as set forth in claim 10, wherein
at least part of said spray nozzles are
35 internal mixing type spray nozzles, said lubricant has a
dynamic viscosity at 40°C of 60 to 800 cSt, and
said gas is fed to said internal mixing type
42
spray nozzles at 0005 MPa or more pressure and the
lubricant is fed at a pressure of not less than the
pressure of the gas in the mixing chambers of the spray
nozzles.
5 Claim 16
A method of supplying a lubricant to a rolling mill
as set forth in claim 10, wherein
at least part of said spray nozzles are
external mixing type spray nozzles, said lubricant has a
10 dynamic viscosity at 40°C of 60 to 800 cSt, and
said gas is fed to said external mixing type
spray nozzles at 0,.05 MPa or more pressure and the
lubricant is fed at a pressure of not less than 0,01 MPa
and not more than the feed pressure of gas to the spray
15 nozzles.