JPH11314106A - Method for grinding roll of inclined roll mill and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automatically remove iron pieces stuck after burning to the outer peripheral surface of a roll without dismounting inclined rolls from the main body of the mill in the inclined roll mill provided with the inclined rolls which are arranged so as to incline them to a material to be rolled. SOLUTION: In this inclined roll mill, plural rolling rolls 1 are arranged so as to incline them around the transfer route R of the material to be rolled. In such a case, a roll grinding device 10 provided with plural grinders 13 on the side of the tip of a moving table 12 which is movable along the transfer route R is installed on the inlet side of the rolling rolls 1, the rotary grinding wheel 14 of each grinder 13 is pressed by holding an approximately constant angle against the outer peripheral surface 1a, 1b of each roll while each rolling roll 1 is being rotated and the moving table 12 along the transfer route R is being advanced and also the pressing pressure of each rotary grinding wheel 14 against the outer peripheral surfaces 1a, 1b is controlled so as to be held constant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inclined roll mill in which a plurality of rolling rolls are arranged so as to be inclined with respect to a material to be rolled around a rod-shaped or tubular material to be rolled. The present invention relates to a roll grinding method and an apparatus used for grinding an outer peripheral surface of each rolling roll to remove iron pieces baked on the surface and repair / rework the outer peripheral surface of the roll. ), Or a thick-walled tube (rolled material) pierced by this piercing-rolling machine
Roll grinding method and apparatus used in a tube rolling mill for reducing the diameter and thickness of a roll by a plurality of inclined rolling rolls.

[0002]

2. Description of the Related Art FIG. 7 shows a main portion of a general piercing and rolling machine as an inclined roll mill, and a pair of upper and lower piercer rolls (rolling rolls for piercing) 1, 1 are omitted from the drawings. A pair of left and right disc rolls (guide rolls)
Are disposed so as to surround the transfer path R of the heated bar-shaped billet W (rolled material). The two piercer rolls 1, 1 are arranged at a predetermined angle with respect to the bar-shaped billet W transferred along the transfer path R and are arranged at positions twisted with respect to each other, and are driven to rotate in the same direction. A bar-shaped billet W guided by a guide 2 (commonly referred to as a cannon guide) and passed between the rolls is formed into a hollow shell with a mandrel M arranged along the axis of the billet W. I have.

FIG. 8 schematically shows a main part of a piercing mill in which the piercer rolls 1, 1 are disposed at predetermined positions in a rolling mill main body. The piercer rolls 1 and 1 are rotatably supported by a rotatable driving means (not shown), respectively. A cylindrical work guide 2 having an inner diameter corresponding to the diameter is provided along the transfer path R. Incidentally, reference numeral 3 in the drawing denotes a guide replacement mechanism.

[0004]

In the process of producing a raw pipe from the bar-shaped billet W by the piercer rolls 1, 1 of the piercing mill as described above, iron pieces may be burned on the outer peripheral surface of the piercer roll 1. If this iron piece is seized on the outer peripheral surface of the roll, the dimensions of the tube to be rolled are damaged, or the surface of the pipe is damaged, thereby deteriorating the product value. There is.

[0005] However, conventionally, when removing the iron pieces that have been seized on the piercer roll 1, an operator enters a narrow space between the rolls and performs the work of removing the iron pieces using a graninder, and depending on the state of seizure of the iron pieces, Stop the pipe production line, remove the piercer roll 1 incorporated in the rolling mill main body from the rolling mill main body,
At another location, iron pieces were removed using a grinder. However, the entry work in the space between the rolls as in the former involves a great danger, and in the latter case, the removal and installation of the piercer roll 1 requires a great deal of time and labor, and the operation rate of the rolling mill is high. Had been lowered.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and in a tilt roll mill provided with a tilt roll arranged to be tilted with respect to a material to be rolled, such as a piercer roll, removing the tilt roll from the roll mill body. It is an object of the present invention to provide a roll grinding method and a roll grinding method capable of automatically removing iron pieces seized on the outer peripheral surface of a roll in the same state without any change, thereby improving work safety and work efficiency. Aim. The present invention is not only for removing iron pieces sticking to the outer peripheral surface of the inclined roll, but also for repairing the outer peripheral surface of the roll due to irregularities, seizure scratches, welds, etc. formed on the outer peripheral surface of the inclined roll due to long-term use. -Applicable to re-grinding.

[0007]

According to a first aspect of the present invention, there is provided a roll grinding method, wherein a plurality of rolling rolls are arranged around a transfer path of a material to be rolled so as to be inclined with respect to the material to be rolled. In the finished inclined roll mill, a roll grinding device 10 provided with a plurality of grinders 13 at the tip side of a movable table 12 movable along the transfer path R is installed at the entrance side of the rolling roll 1, and While rotating the moving table 12 and moving the moving table 12 forward along the transfer path R, the rotating grindstones 14 of the respective grinders 13 are pressed against the outer peripheral surfaces 1a and 1b of the rolling rolls 1 while maintaining a substantially constant angle. It is characterized in that the pressing pressure of each rotary grindstone 14 against the outer peripheral surfaces 1a and 1b of the rolling roll 1 is controlled to be kept constant.

According to a second aspect of the invention, there is provided a roll grinding apparatus comprising:
A roll grinding device in an inclined roll mill in which a plurality of rolling rolls 1 are arranged to be inclined with respect to a material W to be rolled around a transfer path R of the material W to be rolled. A movable frame 12 is supported by a support frame 11 provided along the route R so as to be able to reciprocate back and forth.
A plurality of grinders 13 for grinding the outer peripheral surfaces 1a and 1b of each of the rolling rolls 1 are respectively held at the leading end side of the rolls, and the pressing angles of the rotary grindstones 14 of the respective grinders 13 against the outer peripheral surfaces 1a and 1b of each of the rolling rolls 1 are kept substantially constant. And a constant pressure control means 9 for controlling the pressing pressure of each rotary grindstone 14 against the outer peripheral surface of each rolling roll 1 to be kept constant.

According to a third aspect of the present invention, in the roll grinding apparatus for the inclined roll mill according to the second aspect, each of the fixed angle holding means 8 is constituted by a parallel crank mechanism, and the parallel movement of the parallel crank mechanism is opposed to the fixed link 21. Link 22
A grinder 13 is attached to the distal end of the moving member 12. Each constant pressure control means 9 is provided with a fluid pressure cylinder 26 between the proximal end of the parallel moving link 22 and the distal end of the moving table 12, and 26, the outer peripheral surface 1 of each rolling roll 1
It is characterized in that the pressing pressure of each rotating grindstone 14 is kept constant by performing the expansion and contraction operation in accordance with the fluctuation of the pressing pressure of the rotating grindstone 14 against a and 1b.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a cylindrical work guide 2 arranged at a predetermined position on the inlet side of a pair of piercer rolls 1, 1 in a piercing mill similar to the piercing mill shown in FIG. Roll grinding device 10 of the present invention installed in place of
The detailed structure of the roll grinding apparatus 10 is shown in FIGS. In addition, each piercer roll 1
Is a cone-shaped or barrel-shaped roll as shown in FIG. 1 and FIG.
And a reverse tapered outer peripheral surface 1b on the large-diameter end side.

The roll grinding apparatus 10 supports a movable table 12 on a support frame 11 provided on the entrance side of the piercer rolls 1 and 1 along a transport path R of a material to be rolled so as to be able to reciprocate back and forth. A plurality of grinders 13 for grinding the outer peripheral surface of each piercer roll 1 are provided on the tip side of
The constant angle holding means 8 for maintaining the pressing angle of each rotary grindstone 14 on the outer peripheral surfaces 1a and 1b of each piercer roll 1 substantially constant, and the pressing pressure of each rotary grindstone 14 on the outer peripheral surfaces 1a and 1b of each piercer roll 1 It is provided via constant pressure control means 9 for controlling the pressure to be kept constant.

FIG. 2A is a plan view of the roll grinding apparatus 10, FIG. 2B is a longitudinal sectional side view, and FIGS. 3A to 3C are respective parts of the roll grinding apparatus 10. FIG. As can be seen from these figures, the support frame 11 of the roll grinding device 10 is formed in a gutter shape having an arc-shaped cross section, and a pair of guide rails 15, 15 are provided, and the moving table 12 is provided with sliders 18, 18 on both guide rails 15, 15.
It is movably supported through. In addition, the moving table 12
A screw shaft 17 driven forward and reverse by a forward / reverse motor 16 is vertically threaded and penetrates. The forward / reverse rotation of the screw shaft 17 causes the movable table 12 to move a predetermined stroke along the guide rails 15 and 15. It can be moved back and forth between them.

Further, flanges 19 are mounted on the left, right, front and rear of the support frame 11, and the support frame 11 is held and fixed to the mounting frame 6 of the guide replacement mechanism 3 via these flanges 19. 2 and 3, reference numeral 20 denotes the support frame 1.
1 is an upper support frame protruding from the center of the first support frame.

As can be seen from FIGS. 2 and 4, the fixed angle holding means 8 for holding the pressing angle of each rotary grindstone 14 against the outer peripheral surfaces 1a and 1b of each piercer roll 1 is a link having parallel edges. 21 and 22 are pivotally connected by parallel links 23 and 24 having the same length, and the link 21 is fixed to the distal end of the movable base 12 while being inclined at a fixed angle with respect to the center axis O of the transfer path R. As a result, the translation link 22 facing the fixed link 21
Consists of a parallel crank mechanism capable of moving in parallel with the fixed link 21. The grinder 13 is attached via a bracket 25 to the tip of a parallel link 22 facing the fixed link 21 of the parallel crank mechanism. .

The pressing angle of each rotary grindstone 14 against the outer peripheral surfaces 1a and 1b of each piercer roll 1 is indicated by θ in FIG. The pressing angle θ of the rotating grindstone 14 on the tapered outer peripheral surface 1a on the small diameter end side of each piercer roll 1 and the pressing angle θ of the rotating grindstone 14 on the reverse tapered outer peripheral surface 1b on the large diameter end side may be slightly different. In any case, the pressing angle θ of the rotary grindstone 14 is 15 ° to 30 °.
Then, the parallel crank mechanism of the fixed angle holding means 8 may be configured so as to secure the pressing angle θ in this angle range.

Further, the outer peripheral surfaces 1a,
The constant pressure control means 9 for controlling the pressing pressure of each rotary grindstone 14 against the rotating wheel 1b to be constant is provided by the parallel moving link 2 of the parallel crank mechanism constituting the constant angle holding means 8.
For example, an air cylinder 26 is provided as a fluid pressure cylinder between the base end of the moving table 12 and the distal end of the moving table 12, and the cylinder 26 is connected to the outer peripheral surfaces 1 a and 1 of each piercer roll 1.
The pressing pressure of each rotary grindstone 14 is kept constant by performing the expansion and contraction operation in accordance with the fluctuation of the pressing pressure of the rotary grindstone 14 against b.

The constant pressure control means 9 will be described with reference to FIG. 5. The air cylinder 26 is formed of, for example, a diaphragm type air cylinder having extremely small piston sliding friction resistance, although not shown in detail. The piston rod 26a of the cylinder 26 is operatively connected to the parallel movement link 22 of the parallel crank mechanism constituting the fixed angle holding means 8. The cylinder 26 is connected to the head side chamber S1 and the rod side chamber S2 via a piston 26b. Air lines L1 and L2 communicating with the air source P are connected to the cylinder 26, and the cylinders 26 are connected to both air lines L1 and L2.
Are provided with controllers C1 and C2 for controlling the differential pressure between the two air chambers S1 and S2 to a constant value.

The rotating grindstone 14 is rolled by the grinder 13 and the parallel crank mechanism due to its own weight.
b, and cannot be controlled to a pressure lower than the pressing force due to its own weight.
The pressure equal to the pressing force due to its own weight is applied to cylinder 2
6 to balance and eliminate the pressing force due to its own weight. Further, the controller C1 supplies a pressure equal to the required pressing force to the cylinder 26 to give the rotating grindstone 14 the required pressing force. Then, in order to control the control pressure between the two chambers S1 and S2 of the head side chamber S1 and the rod side chamber S2 of the cylinder 26 to which the control pressure is supplied as described above, the controller C1 is controlled.
C2 has a function of preventing the pressure on the cylinder 26 side from increasing above the control pressure. If the pressure is to increase, the pressure is released to the outside air to keep the pressure constant, and conversely, the pressure decreases. If an attempt is made, the pressure is supplied and compensated by the reduced amount.

Therefore, the rotating grindstones 14 of the respective grinders 13 are moved behind the roll outer peripheral surface 1a as shown by phantom lines in FIG. 4 by the movement of the constant angle holding means 8 and the constant pressure control means 9 due to the forward movement of the movable table 12. Assuming that the movable table 12 continues to move forward from this state assuming that the movable table 12 is pressed against the end position with a constant pressure, the roll outer peripheral surface 1a by the grinder 13
When the grinding of the grinding wheel is started, the rotating grindstone 14 at this time moves while being pressed against the outer circumferential surface 1a of the upwardly inclined roll. Therefore, the pushing pressure of the rotating grindstone 14 tends to increase as the moving table 12 advances. However, the cylinders 26 are contracted by the controllers C1 and C2 which control so as to avoid an increase in the pressing pressure, and the translation link 22 of the parallel crank mechanism constituting the fixed angle holding means 8 moves in the retreating direction. In parallel, the rotating grindstone 14 grinds the outer peripheral surface 1a of the upwardly inclined roll while moving with a constant pressing pressure from the rear end position to the distal end position of the outer peripheral surface 1a of the upwardly inclined roll.

Subsequently, the rotating grindstone 14 moves from the rear end of the upwardly inclined roll outer peripheral surface 1a to the downwardly inclined roll outer peripheral surface 1b. On the outer peripheral surface 1b of the downwardly inclined roll, the pressing pressure of the rotary grindstone 14 tends to decrease with the advancement of the moving table 12, but the controllers C1 and C2 which control so as to avoid the reduction of the pressing pressure are used. When the cylinder 26 extends, the translation link 22 translates in the forward direction, whereby the rotating grindstone 14 is pressed constantly from the rear end position of the downwardly inclined roll outer peripheral surface 1b to a required position in front thereof. The downward inclined roll outer peripheral surface 1b is ground while moving by pressure.

FIG. 6 shows the grinder 13 attached to the distal end of the parallel movement link 22 of the parallel crank mechanism constituting the fixed angle holding means 8. The grinder 13 has a motor (not shown) built-in. A disk-shaped rotary grindstone 14 is attached to a rotary shaft (not shown) protruding from the distal end, and a grindstone cover 28 is attached to the rotary grindstone 14. The grinder 13 is attached to a bracket 25 provided at the tip of the parallel link 22 of the parallel crank mechanism constituting the fixed angle holding means 8.

Next, a method of grinding the outer peripheral surface of the piercer roll 1 using the above-described roll grinding device 10 in order to remove the iron pieces sticking to the piercer roll 1 of the piercing mill will be described. At the time of this grinding, the cylindrical work guide 2 of the piercing mill shown in FIG. 8 is removed, and the roll grinding apparatus 10 of the present invention is mounted at the position shown in FIG. The removal of the work guide 2 and the attachment of the roll grinding device 10 can be automatically and safely performed in a short time by the guide replacement mechanism 3 as schematically shown in FIG.

In grinding, the upper and lower piercer rolls 1 and 1 are respectively rotated in the same direction as shown in FIG. 1, and the movable table 12 is moved forward at a predetermined speed to protrude from the distal end side of the movable table 12. Rotating whetstone 14 of grinder 13
As shown in a phantom line in FIG. 4, the outer peripheral surface 1a of each piercer roll 1 is pressed at a fixed angle to the rear end position, and the pressing pressure of the rotary grindstone 14 against the outer peripheral surface a of each piercer roll 1 is kept constant. The outer peripheral surface 1 of each piercer roll 1 on which the rotating grindstone 14 of each grinder 13 is baked with an iron piece in accordance with the forward movement of the moving table 12
Grind a.

In this case, as shown in FIG. 4, the outer peripheral surface 1a on the rear end side of each piercer roll 1 is a tapered outer peripheral surface 1a that is inclined upward for each grinder 13.
The pressing pressure of each rotary grindstone 14 pressed against the tapered outer peripheral surface 1a at a constant angle tends to increase as the moving table 12 advances, but the fluid pressure cylinder 2 of the constant pressure control means 9
6, the cylinder 26 is contracted so as to avoid an increase in the pressing pressure, and the translation link 22 of the parallel crank mechanism constituting the fixed angle holding means 8 translates in the retreating direction. Each rotating grindstone 14 can grind the upwardly inclined tapered outer peripheral surface 1a while moving with a constant pressing pressure from the rear end position to the distal end position of the upwardly inclined tapered outer peripheral surface 1a.

The rotary grindstone 14 of each grinder 13 that has finished grinding the upwardly inclined tapered outer peripheral surface 1a of each piercer roll 1 continues with the downwardly inclined outer periphery of the piercer roll 1 as the moving table 12 moves forward. Move to the surface 1b side. On the outer circumferential surface 1b of the downwardly inclined roll, the pressing pressure of the rotary grindstone 14 tends to decrease as the moving table 12 advances, but the fluid pressure cylinder 26 of the constant pressure control means 9
Is operated to extend the cylinder 26 so as to avoid a decrease in the pressing pressure, whereby the translation link 22 translates in the retreating direction. The outer circumferential surface 1b of the downwardly inclined roll while moving at a constant pressing pressure from the rear end position of the outer circumferential surface 1b to a required position in front of the outer circumferential surface 1b.
Can be ground.

In the roll grinding apparatus 10, the rotating grindstones 14 of the respective grinders 13 move in an arc by the parallel crank mechanism of the fixed angle holding means 8, while the tapered outer peripheral surface 1 a of the piercer roll 1 is inclined upward. Alternatively, since the reciprocating displacement or the forward displacing is performed along the outer peripheral surface 1b of the downwardly inclined roll, each of the rotating grindstones 14 is smoothly adapted to the outer peripheral surfaces 1a and 1b of the roll to obtain extremely good grinding accuracy. be able to.

Further, in the roll grinding apparatus 10, the fixed angle holding means 8 comprises a parallel crank mechanism, and a bracket 25 is provided at a tip end of a parallel moving link 22 facing a fixed link 21 of the parallel crank mechanism. A grinder 13 is attached, and a constant pressure control means 9 is provided.
Is a fluid pressure cylinder 26 between the proximal end of the translation link 22 of the parallel crank mechanism and the distal end of the moving table 12.
This cylinder 26 is inserted into each piercer roll 1
Is made to expand and contract in accordance with the fluctuation of the pressing pressure of the rotating grindstone 14 on the outer peripheral surfaces 1a and 1b of the rotating grindstones 14, so that the pressing pressure of each rotating grindstone 14 is kept constant. Each of the constant pressure control means 9 can be made compact with a simple structure, and each can be manufactured at a low cost.

According to the grinding method using the roll grinding device 10 as described above, it is not necessary to remove the piercer roll 1 from the rolling mill main body in order to remove the iron pieces sticking to the piercer roll 1 of the piercing mill. , With the outer surface 1 of the piercer roll 1 attached as it is
It is possible to automatically remove the iron pieces sticking to a and 1b, so that the iron pieces can be removed very safely and efficiently.

In the embodiment described above, only the case where the iron pieces seized on the outer peripheral surfaces 1a and 1b of the piercer roll of the piercing mill are described, but the present invention relates to a thick wall formed by piercing by this piercing mill. The present invention can be applied to the removal of iron pieces sticking to the outer peripheral surface of a roll in a tube material rolling mill for reducing the diameter and the thickness of a raw tube by a plurality of inclined rolling rolls. Also, not only when removing the iron pieces sticking to the outer peripheral surface of the inclined roll, but also when re-grinding the outer peripheral surface of the roll due to irregularities formed on the outer peripheral surface of the inclined roll due to long-term use. Applicable.

[0030]

According to the roll grinding method and apparatus of the present invention, there is provided an inclined roll mill comprising a plurality of rolls inclined around a transfer path of a rod-shaped or tubular material to be rolled, the roll roll being inclined with respect to the transfer path. Remove the iron pieces that are seized on the outer peripheral surface of the rolling roll, or repair the outer peripheral surface of the roll.
In order to grind the outer peripheral surface of each rolling roll for reworking, it is not necessary to remove the rolling roll from the apparatus body each time, and the outer peripheral surface of the roll can be automatically ground as it is, so that the grinding work is performed. Can be performed very safely, and the work efficiency can be greatly improved.

In particular, according to the present invention, the rotating grindstones of the respective grinders are pressed against the outer peripheral surface of each of the rolling rolls while maintaining a substantially constant angle, and the pressing pressure of each rotating grindstone against the outer peripheral surface of each of the rolling rolls is controlled to be constant. Thus, the outer peripheral surface of the roll can be accurately and accurately ground regardless of the inclination of the outer peripheral surface of the roll.

Further, in the roll grinding apparatus of the present invention, the fixed angle holding means of the roll grinding apparatus comprises a parallel crank mechanism, and a grinder is attached to a tip of a parallel moving link opposed to a fixed link of the parallel crank mechanism. In addition, a constant pressure control means interposes a fluid pressure cylinder between a base end of the translation link of the parallel crank mechanism and a tip end of the moving table, and applies the cylinder to a rotating grindstone with respect to an outer peripheral surface of each rolling roll. If the pressing pressure of each rotary grindstone is kept constant by expanding and contracting according to the fluctuation of the pressing pressure, the rotating grindstones of each grinder will move in an arc by the parallel crank mechanism of the fixed angle holding means. While moving back and forth along the outer peripheral surface of the rolling roll up or down. There familiar smoothly relative to the roll outer surface, it is possible to obtain a very good grinding accuracy,
In addition, the fixed angle holding means and the constant pressure control means can each be configured compactly with a simple structure, and can be manufactured at low cost.

[Brief description of the drawings]

FIG. 1 is a sectional side view showing a state in which a roll grinding device according to the present invention is installed in a piercing mill.

FIG. 2A is a plan view of a roll grinding device of the present invention,
(B) is a vertical side view of the roll grinding device.

FIG. 3A is an enlarged cross-sectional view taken along line XX of FIG. 2B.
2B is an enlarged cross-sectional view taken along the line YY of FIG. 2B, and FIG. 2C is an enlarged cross-sectional view taken along the line ZZ of FIG. 2B.

FIG. 4 is an enlarged detailed side view illustrating a grinding method of the present invention.

FIG. 5 is a circuit diagram showing a constant pressure control unit of the roll grinding device of the present invention.

FIG. 6 is a side view showing a grinder.

FIG. 7 is an explanatory view illustrating a method of piercing a bar-shaped billet by a piercer roll of a piercing mill.

FIG. 8 is a sectional side view showing a normal use state of the piercing mill;

[Explanation of symbols]

REFERENCE SIGNS LIST 1 piercer roll (rolling roll) 1 a, 1 b outer peripheral surface of piercer roll (rolling roll) 8 constant angle holding means 9 constant pressure control means 10 roll grinding device 11 support frame 12 moving table 13 grinder 14 rotating grindstone 21 fixed link of parallel crank mechanism 22 Parallel moving link opposed to fixed link of parallel crank mechanism 23, 24 Parallel link of parallel crank mechanism 26 Fluid pressure cylinder C1, C2 Controller

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Fumio Matsumura 1-9-1, Jokoji, Amagasaki-shi, Hyogo Prefecture Inside Fuji Industrial Co., Ltd. (72) Inventor Shin-ichi Yamakawa 1-9-1, Jokoji, Amagasaki-shi, Hyogo Prefecture Osaka Fuji Industry Co., Ltd.

Claims (3)

[Claims] 1. An inclined roll mill in which a plurality of rolling rolls are arranged around a transfer path of a material to be rolled so as to be inclined with respect to the material to be rolled, a tip side of a movable table movable along the transfer path. A roll grinding device equipped with a plurality of grinders is installed at the entrance side of the rolling rolls, and while rotating each rolling roll and moving the moving table along the transfer path, the rotating grindstone of each grinder is rolled into each rolling roll. A roll grinding method for a tilted roll mill, characterized in that the pressing is performed while maintaining a substantially constant angle against the outer peripheral surface of each of the rolls and that the pressing pressure of each rotary grindstone against the outer peripheral surface of each of the rolling rolls is maintained constant. 2. A roll grinding apparatus in an inclined roll mill, wherein a plurality of rolling rolls are arranged around a transfer path of a material to be rolled so as to be inclined with respect to the material to be rolled, wherein the roll grinding device is provided at an inlet side of the rolling roll. A movable frame is supported on a support frame provided along a transfer path so as to be able to reciprocate back and forth, and a plurality of grinders for grinding the outer peripheral surface of each rolling roll are provided on the distal end side of the movable table. Equipped with fixed angle holding means for maintaining the pressing angle of each grinder rotating grindstone to almost constant, and constant pressure controlling means for controlling so as to keep the pressing pressure of each rotating grindstone against the outer peripheral surface of each rolling roll constant. A roll grinding device for an inclined roll mill, comprising: 3. The fixed angle holding means comprises a parallel crank mechanism. A grinder is attached to a tip of a parallel movement link opposed to a fixed link of the parallel crank mechanism. A fluid pressure cylinder is interposed between the base end of the link and the tip of the moving table, and the cylinder is extended and contracted in accordance with a change in the pressure of the rotating grindstone against the outer peripheral surface of each rolling roll. 3. The roll grinding device according to claim 2, wherein the pressing pressure of each rotary grindstone is kept constant.