JPH08170294A - Doctor device - Google Patents

Abstract

PURPOSE: To smoothly treat the surface of a high temperature roll with a doctor blade by controlling the volume of cooled water flown into an expandable or contractible tube to control the press force of the doctor blade. CONSTITUTION: In the doctor device for scratching foreign matters adhered to the surface of a high temperature roll such as a roll for rolling steel, one long side of a 0.1-0.4mm long and narrow rectangular doctor blade 12 which has a blade edge 121 at the edge of the other long side is held with a holder 13. The holder 13 is supported with a doctor back 14, and journal shafts 141 attached to both the sides of the doctor back 14 are attached to a frame 15 through bearings 16 in a state capable of being rotated in an opening direction (arrow A) separating from the surface S of the roll and in the press direction (arrow B). An expandable or contractible tube 143 is mounted between the back surface of the finger 132 of the holder 13 and the upper surface of the doctor back 14, and cooled water is charged from a cooled water-charging pipe into the tube 143 through a flow volume control valve and an inner pressure control valve to simultaneously control the press pressure of the doctor blade 12 and cool the tube itself 143 due to the expansion or contraction of the tube 143.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a doctor device used for scraping off foreign matters adhering to the surface of a roll such as a steel-making rolling roll. More specifically, the present invention relates to a high temperature doctor device suitable for scraping foreign matter from the surface of a high temperature roll or a roll placed in a high temperature atmosphere.

[0002]

2. Description of the Related Art When foreign matter such as paper slag adheres to the surface of a paper machine roll used in a paper machine, it causes troubles such as breakage of conveyed paper. In order to avoid this, each paper machine roll is provided with a doctor device for scraping off foreign matter adhering to the surface thereof.

As a doctor device for a paper machine roll,
The air tube type shown in FIG. 4 is generally used. As shown in this figure, a doctor device 1 supports an elongated rectangular doctor blade 2 having a cutting edge portion that is pressed against a roll surface, a blade holder 3 that holds the proximal end side of the doctor blade 2, and a holder 3 that supports the holder 3. It consists of a doctor back 4 The doctor back 4 is rotatably supported by bearings on the side of a mount (not shown) on which journal shafts 4a attached to both ends thereof are fixedly arranged. A turnbuckle (not shown) is connected between the doctor back 4 and the gantry, and by adjusting this, the doctor back 4 can be fixed in an arbitrary turning angle posture.

The blade holder 3 is supported on the doctor back 4 side in a rotatable state about the connecting rod 3a. A blade opening tube 5 is arranged on the front side of the connecting rod 3a, and a blade pressing tube 6 is arranged on the rear side. These tubes 5,
6 is made of a flexible material, and when the tube 5 side is expanded, the blade holder 3 holding the doctor blade 2 moves the doctor blade 2 away from the surface of the roll R about the connecting rod 3a. That is, it turns in the opening direction. When the other tube 6 is expanded, the blade holder 3 swivels in the direction in which the doctor blade 2 is pressed against the surface of the roll R, that is, in the pressing direction.

The expansion and contraction of these tubes 5 and 6 are
This is done by controlling the supply of air to these. That is, the air supply path from the air source 7 communicates with the tubes 5 and 6 via the pressure regulating valve 8 and the four-way switching valve 9. When the switching valve 9 is set to the switching position shown in the figure, the pressurizing tube 6 expands. Conversely, when the switching valve is switched, the opening tube 5 expands.

As described above, in the conventional general air tube type doctor device, by controlling the supply of air to the pair of tubes 5 and 6, the blade edge of the doctor blade 2 is brought to the surface of the roll R with an appropriate pressure. I try to make pressure contact.

Here, the dimensions and the like of each part in a general air tube type doctor device are as follows. First, the contact pressure of the blade of the doctor blade against the roll surface is set to about 300 to 400 g in linear pressure. Doctor blade thickness is about 0.9 mm to 1.2
mm. The inner diameter of the tube is set to about 30 mm, and the tube is made of a material such as canvas.

[0008]

The doctor device as described above is conventionally used for a paper machine roll.

However, the step of forming a sheet-like material using a roll is not limited to the paper manufacturing industry. For example, in the steel industry, many rolls such as rolling rolls are used.

Also in these rolls, if foreign matter such as dust adheres to the surface of the roll, problems such as unevenness on the surface of the formed sheet occur. As a method of removing the foreign matter attached to the surface of the rolling roll, generally, a method using a brush roll, a method of reciprocating a brush along the roll surface, and the like are adopted. However, it is difficult to reliably remove the foreign matter attached to the roll surface by such a conventional method.

Therefore, it is conceivable to scrape off the foreign matter adhering to the surface of the iron-making roll by using the above-mentioned air tube type doctor device. However, the doctor device used for a paper machine roll cannot be used as it is for a steelmaking roll such as a rolling roll. In particular, some ironmaking rolls are placed in a high temperature atmosphere or have a high temperature. For example, if the above-mentioned air tube type doctor device is used as it is for a high temperature roll which is arranged near the furnace outlet and whose surface temperature is heated to 600 degrees Celsius, there are the following problems.

First, the air inside the pressurizing and releasing air tube may also be heated to a high temperature and expand, causing the tube to burst. Also, since the tube material is not heat resistant, it deteriorates quickly when used in a high temperature atmosphere. In particular, the air tubes for opening are often not supplied with air, so they deteriorate quickly.

On the other hand, as can be seen from FIG. 3 showing the embodiment of the present invention, the doctor blade pressed against the surface of the high temperature roll is heated to the high temperature on the blade edge side, but is held on the blade holder side. The base end side is not heated so much. For this reason, the doctor blade is unbalanced in temperature, and a difference in thermal expansion amount between the blade tip side and the base end side is possible. As a result, as shown in FIG. 5, thermal deformation such as wavy undulation occurs at the cutting edge portion on the high temperature side. When such thermal deformation occurs, each part of the cutting edge will not come into contact with the surface of the high-temperature roll with an appropriate pressure contact force, and scraping will not be performed properly.

The object of the present invention is to solve the above problems.
It is to realize a high temperature doctor device suitable for use in a high temperature atmosphere or for a high temperature roll.

[0015]

In order to solve the above problems, in the doctor device of the present invention, the pressurizing tube of the doctor blade is expanded and contracted by supplying a cooling liquid such as water. The cooling liquid is always kept flowing in the pressurizing tube to efficiently cool the pressurizing tube. Further, the opening operation of the doctor blade is performed by adjusting the turnbuckle supporting the doctor back without using the opening tube arranged near the roll.

That is, according to the present invention, a doctor blade for scraping off deposits on the surface of a roll such as an iron-making roll, a blade holding portion holding the doctor blade, and the blade holding portion are held therein. Expansion for swiveling the bearing and the blade holding part, which are supported in a rotatable state in the pressing direction in which the blade edge of the doctor blade is pressed against the roll surface and the opening direction opposite to this, and the blade holding part in the pressing direction. A cooling unit for supplying a cooling liquid to the expansion / contraction tube, and a cooling unit for supplying the cooling liquid to the expansion / contraction tube. The liquid supply means and the expansion amount by controlling the supply amount of the cooling liquid supplied by the cooling liquid supply means
And an adjusting means for adjusting the expansion amount of the shrinkable tube.

In order to adjust the expansion amount of the cooling liquid flowing through the tube, a cooling liquid flow control valve is arranged on the side of the cooling liquid inlet of the tube and the internal pressure of the tube is arranged on the side of the cooling liquid outlet of the tube. A configuration in which an internal pressure adjusting valve for adjusting the pressure is arranged may be adopted. Water can be used as the cooling liquid.

Next, in a preferred embodiment of the present invention, the supporting portion is rotatably movable in the pressurizing direction and the opening direction about a supporting portion turning axis parallel to the turning axis of the blade holding portion. The support part is supported on the side of the frame, and the support part turning shaft is set at a position where the rotational moment in the pressing direction about the support part always acts on the support part. Then, the restraint member installed at a fixed position such as a gantry may prevent the support portion from turning in the pressing direction. According to this structure, unlike the case where the support part is fixed so as not to rotate by using the turnbuckle, the doctor device can rotate in the opening direction, but it is restrained by the rotation moment due to the weight of the doctor device. Has been done. Therefore, the doctor device becomes flexible as a whole as compared with the case where the doctor device is fixed by a turnbuckle or the like, so that the blade contact with the roll surface of the doctor blade is maintained in an appropriate state.

If a cam provided as a restraining member is used and the cam follower engaged with the cam is fixed to the side of the supporting portion, the cam is moved to move the supporting portion, that is, the doctor device. Can be easily turned to the open side.

On the other hand, in the present invention, the doctor blade is thinner than the conventionally used doctor blade so that the doctor blade is not thermally deformed by heating. That is, in the present invention, the thickness of the doctor blade is in the range of about 0.1 mm to about 0.5 mm. A preferred thickness is 0.4 mm or less. By making it thin in this way, the thermal deformation of the doctor blade can be suppressed to such an extent that it does not hinder practical use even when used in a high temperature atmosphere of 200 ° C. or higher.

Here, in order to further suppress the thermal deformation of the doctor blade, a slit extending in the short side direction is oriented in the long side direction at the base end side portion of the doctor blade held by the blade holding portion. It is preferable to form them at predetermined intervals. Thermal deformation is absorbed by the slit.

[0022]

In the doctor device of the present invention, a cooling liquid such as water is constantly flowed through the pressurizing tube. Further, the expansion amount is adjusted by individually adjusting the inflow amount and the outflow amount. Therefore, the pressurizing tube is always cooled, and the pressure applied by the tube is adjusted by the supply amount of the cooling liquid. As a result, it is possible to apply a doctor device capable of achieving a proper blade contact state by the expansion / contraction tube to a high temperature roll such as a steelmaking roll.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the construction of a doctor device for a high temperature roll which is an embodiment of the present invention. The doctor device 11 for the high temperature roll of this example also has a slender rectangular doctor blade 12, a blade holder 13 holding the base end side thereof, and the blade holder 13 like the conventional device.
Is provided with a doctor back 14. Journal shafts 141 are fixed to both ends of the doctor back 14, and these journal shafts 141 are rotatably supported on the pedestal 15 side via bearings 16 attached to the pedestal 15.

The edge of the doctor blade 12 on the tip side serves as a cutting edge 121 and is pressed against the surface S of the high temperature roll R with a predetermined pressure contact force during operation. The blade holder 13 is a slender rectangular top plate 131.
And a large number of fingers 132 mounted on the back side at regular intervals in the long side direction. Top plate 1
Between the tip of 31 and the tip of finger 132,
The doctor blade 12 is inserted and held there.

A through hole 133 of the connecting rod 144 is formed in the center of the lower surface of the finger 132. On the other hand, bearing brackets 142 for the connecting rods 144 are attached to both ends of the upper surface of the doctor back 14. The connecting rod 144 is attached so as to pass through the bearing brackets 142 at both ends and the through holes 133 of the fingers 132, and with the rod 144 as the center,
The blade holder 13 is rotatable in an opening direction (arrow A) away from the roll surface S and a pressing direction (arrow B) toward the roll surface S.

The rear side of the connecting rod 144, that is,
On the side away from the roll surface S, an expandable / contractible tube 143 is mounted between the rear surface of the finger 132 and the upper surface of the doctor back 14. When the tube 143 expands, the doctor blade 12 held by the blade holder 13 about the connecting rod 144 pivots in the pressing direction A, and the pressing force of the blade edge 121 against the roll surface S increases.

A lever 145 functioning as a cam follower is integrally attached to the journal shaft 141 attached to the end of the doctor back 14, and this lever 145 is attached.
Extends from the journal shaft 141 toward the side opposite to the doctor blade 12. Tip part 1 of this lever 145
The upper surface of 45 a abuts on a cam surface 171 formed on the outer circumference of the disk cam 17. The cam 17 is an eccentric cam, and the eccentric shaft 172 is rotatably supported by a bearing 173 attached to a fixed position, and has a cam lever for manual operation extending in the radial direction of the eccentric shaft at the other end. 174 is fixed.

As can be seen from FIG. 1 (a), when the cam lever 174 extends vertically upward, the cam surface 171 which is in contact with the upper surface of the lever 145 is in the most retracted state. From this state, when the cam lever 174 is turned in the direction indicated by the arrow C to extend vertically downward as indicated by the imaginary line, the cam 17 rotates integrally with this and hits the upper surface of the lever 145. The cam surface 171 that is present is in the state of protruding most downward. As a result, the lever 145 moves downward, and the journal shaft 141 to which it is attached also rotates in the direction of arrow C. Therefore, the entire doctor device 11 turns about the journal shaft 141 in the opening direction A by a predetermined amount.

Here, the rotational moment M due to the weight of the doctor device 11 about the journal shaft 141 is shown in FIG.
The position of the journal shaft 141 or the weight distribution of the entire doctor device is set so as to act in the pressurizing direction as shown in (a).

As a result, the lever 145 of the doctor back 14 is moved by the rotational moment M that is always acting.
The cam surface 171 of the cam 17 is always pressed by a predetermined force.

Similarly, in the present example, the blade holder 13 is also set so that the rotational moment in the direction of arrow m always acts by its own weight about the connecting rod 144 which is the center of rotation. That is, the moment that tries to turn in the opening direction acts. Therefore, when the pressurizing tube 143 contracts, the blade holder 13 swivels in the opening direction following the contraction. In addition, as described above, when the cam lever 174 is turned to the open side,
Following this, the blade holder 13 also turns to the open side.

Next, with reference to FIG. 2, a mechanism for expanding / contracting and cooling the expandable / contractible pressurizing tube 143 will be described. The pressurizing tube 143 is
It is made of a heat-resistant cloth material containing glass fibers.
The cooling water supply pipe 21 is connected to one end thereof, and the cooling water discharge pipe 22 is connected to the other end thereof. The cooling water supply pipe 21 is connected to a cooling water supply source 24 via a flow rate adjusting valve 23. A pressure gauge 25 for measuring the inlet pressure is attached to the cooling water supply pipe 21.

On the other hand, the cooling water discharge pipe 22 is connected to the drain side 27 via the internal pressure adjusting valve 26, and
A pressure gauge 28 for measuring the outlet pressure is attached.

In this example, the cooling water always flows through the tube 143 during operation. Therefore, the tube 143 is not overheated. Further, the supply amount of the cooling water can be adjusted using the flow rate adjusting valve 23 on the inlet side and the internal pressure adjusting valve 26 on the outlet side, whereby the expansion / contraction amount of the tube can be adjusted. In this way, in this example, the cooling water can be used to simultaneously adjust the pressing force of the doctor blade 12 by the tube and cool the tube itself.

The structure and material of the doctor blade 12 used in this example will be described with reference to FIG. In this example, as the material of the doctor blade 12, K monel steel having high heat resistance and low wear at high temperature is used. Moreover, the thickness is set to about 0.4 mm. The reason for this is about 0.5
When a doctor blade with a thickness of more than mm is used in a high temperature condition of 200 degrees Celsius or more, thermal deformation is severe and an appropriate doctor ring cannot be formed. When it is thinner than this, thermal deformation can be suppressed and it is appropriate. This is because the result was that it was possible to perform a doctor ring. When used in a high temperature roll for iron making, it is suitable to have a thickness of about 0.4 mm.

Further, the doctor blade 12 has a different heating state between the blade tip side and the portion held by the blade holder 13. That is, as shown in FIG.
The side of the cutting edge 121 pressed against the hot roll R has a high temperature, while the side held by the blade holder 13 is far from the hot roll surface S and inside the tube 143 arranged on the rear side of the blade holder. The temperature is not so high because it is cooled by the flowing cooling water. If such a temperature difference occurs, as described with reference to FIG. 5, the doctor blade is thermally deformed and wavy undulation is generated. In this example, the doctor blade 14
3 is made as thin as about 0.4 mm to prevent thermal deformation. However, in order to reliably suppress thermal deformation, the
As shown in (b), it is preferable that the slits 122 be formed at regular intervals in the portion held by the blade holder 13.

For example, according to an experiment by the present inventor, FIG.
As shown in (c), the pitch is 20 mm and the width is about 2 m.
When the slit 122 having a length of m and a length of about 20 mm was formed, thermal deformation of the doctor blade could be reliably suppressed, and an appropriate doctor ring could be realized.

The shape of the slit 122 is shown in FIG.
Although it may be a rectangle having a constant width as shown in FIG.
Of course, the trapezoidal shape as shown in FIG. 3D or FIG. The length, width and shape of the slit are
Basically, it should be appropriately set according to the usage environment of the doctor device.

[0040]

As described above, in the doctor apparatus of the present invention, only the pressurizing tube separated from the high-temperature roll is used, and the cooling water is constantly flowed therethrough, and the doctor blade is adjusted by adjusting the inflow amount. It is possible to adjust the applied pressure. Therefore, according to the present invention, even when used in a doctor ring of a high temperature roll such as a steel-making roll, the tube damage is avoided as in the conventional air tube type doctor device, and the tube type is avoided. The advantages of the pressure system can be used.

Further, in the present invention, since the doctor blade is opened by utilizing the cam mechanism, it is not necessary to use the air tube for opening as in the prior art.
The doctor device can be opened by a simple operation.

Further, in the present invention, the doctor blade has a thickness of about 0.5 mm or less. In addition to or in addition to this, a configuration is adopted in which a slit is formed in a portion held by the blade holder. By adopting this configuration, thermal deformation of the blade holder can be suppressed. Therefore, in the doctor ring of a high-temperature roll or the doctor ring in a high-temperature atmosphere, it is possible to avoid the adverse effect that the doctor blade is thermally deformed and an appropriate blade contact state cannot be obtained.

[Brief description of drawings]

1A and 1B are diagrams showing a doctor device according to an embodiment of the present invention, in which FIG. 1A is a schematic configuration diagram as seen from a side thereof, and FIG. Is.

FIG. 2 is a configuration diagram showing a cooling water supply control mechanism for a pressurizing tube of the doctor device of FIG.

3A and 3B are views showing a structure of a doctor blade of the doctor device shown in FIG. 1, in which FIG. 3A is an explanatory view for explaining a temperature difference between a cutting edge side and a base end side thereof, and FIG. Figure,
(C) is a partially enlarged plan view, and (d) and (e) are partially enlarged plan views showing a modified example of the slit.

FIG. 4 is a configuration diagram of an air tube type doctor device used for a conventional paper machine roll.

5 is an explanatory view showing thermal deformation of a doctor blade when the doctor device of FIG. 4 is used.

[Explanation of symbols]

 11 ... Doctor Device 12 ... Doctor Blade 121 ... Blade Edge 122 ... Slit 13 ... Blade Holder 133 ... Connecting Rod Through Hole 14 ... Doctor Back 141 ... Journal Shaft 143. ..Pressure tube 144 ... Connection rod 145 ... Lever 15 ... Frame 16 ... Bearing 17 ... Cam 171 ... Cam surface 172 ... Eccentric shaft 174 ... Cam lever 21 ...・ ・ Cooling water supply pipe 22 ・ ・ ・ Cooling water discharge pipe 23 ・ ・ ・ Flow rate adjusting valve 24 ・ ・ ・ Cooling water supply source 26 ・ ・ ・ Internal pressure adjusting valve 27 ・ ・ ・ Drainage side R ・ ・ ・ Roll S ・ ・・ Roll surface

Claims (17)

[Claims] 1. A doctor blade for scraping off deposits on the surface of a roll such as an iron-making roll, a blade holding portion holding the doctor blade, and a doctor blade for holding the blade holding portion therein. An expansive / contractible tube for swiveling the bearing and the blade holding part rotatably supported in the pressing direction in which the blade edge is pressed against the roll surface and in the opening direction opposite thereto and in the pressing direction. And a cooling means for supplying a cooling liquid to the expansion / contraction tube, the cooling means is a cooling liquid supply means for flowing the cooling liquid through the expansion / contraction tube, and the cooling means. Adjusting means for adjusting the expansion amount of the expansion / contraction tube by controlling the supply amount of the cooling liquid supplied by the liquid supply device. Doctor device characterized by. 2. The adjusting device according to claim 1, wherein the adjusting means is connected to the cooling liquid inlet of the expansion / contraction tube to adjust the flow rate of the cooling liquid flowing in the expansion / contraction tube. A cooling liquid flow rate control valve; and an internal pressure adjusting valve connected to the cooling liquid outlet of the expansion / contraction tube to adjust the pressure in the expansion / contraction tube. Doctor device. 3. The doctor device according to claim 2, wherein the cooling liquid is water. 4. The support unit according to claim 3, wherein the support unit is supported on the side of the gantry so as to be rotatable in the pressurizing direction and the opening direction about a support unit rotation axis parallel to the rotation axis of the blade holding unit. The support portion turning shaft is set at a position where the rotational moment in the pressurizing direction about the support portion always acts on the support portion, and the support member is arranged at a fixed position. The restraint member prevents rotation in the pressing direction, the restraint member includes a cam, and the support portion includes a cam follower engaged with the cam, and the cam follower is moved by moving the cam. The doctor device, wherein the support portion is swung in the opening direction via a. 5. The doctor device of claim 4, wherein the doctor blade has a thickness in the range of about 0.1 mm to about 0.4 mm. 6. The doctor blade according to claim 5, wherein the doctor blade has an elongated rectangular shape, and a cutting edge is formed on an edge of one long side of the doctor blade, and a portion of the other long side is held by the blade holding portion. In the portion held by the blade holding portion, slits having a predetermined length extending in the short side direction at predetermined intervals in the long side direction are formed. Doctor device to do. 7. The support unit according to claim 1, wherein the support unit is supported on a pedestal side in a state of being rotatable in the pressurizing direction and the opening direction about a support unit rotation axis parallel to the rotation axis of the blade holding unit. The support portion turning shaft is set at a position where the rotational moment in the pressurizing direction about the support portion always acts on the support portion, and the support member is arranged at a fixed position. A doctor device characterized in that the restraint member prevents the turning in the pressing direction. 8. The support member according to claim 7, wherein the restraint member includes a cam, and the support portion includes a cam follower engaged with the cam, and the support is provided via the cam follower by moving the cam. A doctor device, wherein the portion is adapted to be swung in the opening direction. 9. The doctor device of claim 1, wherein the doctor blade has a thickness in the range of about 0.1 mm to about 0.5 mm. 10. The doctor device according to claim 9, wherein the doctor blade has a thickness of about 0.4 mm or less. 11. The doctor blade according to claim 1, wherein the doctor blade has an elongated rectangular shape, a cutting edge is formed on one long side edge thereof, and the other long side portion is held by the blade holding portion. In the portion held by the blade holding portion, slits having a predetermined length extending in the short side direction are formed at predetermined intervals in the long side direction. And doctor equipment. 12. The doctor device of claim 11, wherein the doctor blade has a thickness in the range of about 0.1 mm to about 0.5 mm. 13. The doctor device according to claim 12, wherein the doctor blade has a thickness of about 0.4 mm or less. 14. A doctor having a doctor blade for scraping off deposits on the surface of a roll such as a steel-making roll, a blade holding part holding the doctor blade, and a supporting part supporting the blade holding part. A doctor device, wherein the doctor blade has a thickness in the range of about 0.1 mm to about 0.5 mm. 15. The doctor device according to claim 14, wherein the doctor blade has a thickness of about 0.4 mm or less. 16. The doctor blade according to claim 15, wherein the doctor blade has an elongated rectangular shape, and a cutting edge is formed on an edge of one long side of the doctor blade, and a portion of the other long side is held by the blade holding portion. In the portion held by the blade holding portion, slits having a predetermined length extending in the short side direction are formed at predetermined intervals in the long side direction. And doctor equipment. 17. A doctor having a doctor blade for scraping off deposits on the surface of a roll such as an iron-making roll, a blade holding part holding the doctor blade, and a supporting part supporting the blade holding part. In the apparatus, the doctor blade has an elongated rectangular shape, a cutting edge is formed on one long side edge thereof, and the other long side portion is a portion held by the blade holding portion, A doctor device characterized in that slits of a predetermined length extending in the short side direction are formed at predetermined intervals in the portion held by the blade holding portion in the long side direction.