JPS6068104A - Skew rolling mill - Google Patents

Abstract

PURPOSE:To obtain a titled mill capable of stably rolling a blank pipe without damaging its surface by slantly arranging a pair of driving roll shoes, having each inlet and outlet face angles, at the adjacent positions to rolling rolls so as to provide the fixed advancing angles to them respectively. CONSTITUTION:In a skew rolling mill, where rolling rolls having each inlet and outlet face angles are slantly arranged at about 10-12 deg. advancing angles, and a round billet 25 is forced-in on a trough 24 by a pusher 27 through a cannon 26, to pierce a blank pipe by a plug 23 held by a plug bar 22; a pair of driving roll shoes 2 having each inlet and outlet face angles, used for reducing the outer diameter of pipe from the central part of the axial direction to the inlet and outlet side ends, are arranged at the upper and lower positions between the rolls 21 by slanting them at preferably about >=3 deg. advancing angles, and are forcibly rotated at the higher speed than the peripheral speed of roll 21 by hydraulic motors 31 through universal couplings 30. Further, the forced driving force is preferably set so that the tangential force of shoe with respect to the blank pipe is set to >=3% of the reaction of shoe.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an inclined rolling mill used for manufacturing seamless steel pipes.

In the drilling process of JI-1 steel pipe, two rolling rolls having an entrance side angle and an exit side angle are arranged inclined at a constant advance angle, and a fixed shoe and a dinuk shoe are installed between the rolling rolls. , an inclined rolling mill equipped with kite shoes such as roller shoes is used.

FIG. 1 is a front view showing a rolling roll 1, a plug 2, a blank tube 3, and a fixing shoe 4 in an inclined rolling mill. Base pipe 3
is pulled in the tangential direction by the circumferential speed of the rolling roll l, collides with the fixed shoe 4 and slides, so that the fixed shoe 4 is , -Abrasion parts 5A, 5B, and 5 as shown in FIGS. 2 and 3 are formed on the - side. In addition, in FIG. 2, 5A shows a worn part when a thin-walled raw pipe is rolled, and 5B shows a worn part when a thick-walled raw pipe is rolled. Furthermore, a fine rack is formed on the shoe surface of the fixed shoe 4, which is thought to be caused by thermal stress. Therefore, in an inclined rolling mill using a constant shoe 4, rolling is carried out frequently in order to prevent the worn parts and cranks generated on the shoe surface of the fixed shoe 4 from damaging the surface of the raw pipe 3. It is necessary to stop and clean the shoe surface of the fixed shoe 4 using a grinder or the like. however,
The life of the fixed shoe 4 is short, and in order to alleviate these disadvantages even a little, the fixed shoe 4 is made of high-grade material with good wear resistance, which reduces the production cost of seamless steel pipes. is very large.

FIG. 4 is a front view showing the disc shoe 6 in the inclined rolling mill. The disc shoe 6 is supported by a bearing 8 via a shaft 7 and can be driven by a drive motor 9. This disc shoe 6 has a diameter that is extremely large, reaching approximately 3 m, for example, in order to provide an appropriate surface for contacting the raw pipe 3, making the entire equipment long and difficult to apply to conventional equipment. It is impossible. Also,
Comparing the circumferential speed of the rolling roll 1 and the advancing speed of the raw tube 3, it is about 6:1, and when using the disc shoe 6 that rotates in the direction of movement of the raw tube 3, the ratio between the raw tube 3 and the disk shoe is 85% of the time will occur as a slipping phenomenon,
Inconveniences regarding the life of the disk shoe 6 and surface scratches on the raw tube 3 cannot be satisfactorily solved.

FIG. 5 is a front view showing a roller shoe 10 in an inclined rolling mill. This roller shoe 10 is an idle roller, and although it rotates, it is not forcibly driven. Therefore, in this case, since the roller shoe 10 is an idle roller, if the raw tube 3 escapes into the gap between the rolling roll l and the roller shoe 10, the roller shoe 10 will not pull out the raw tube 3. , rolling may stop and cause a stay anchor phenomenon. To prevent the occurrence of the above-mentioned stay/ink phenomenon, the rolling roll 1 and the roller shoe 1
It is also conceivable to insert the guide plate 11 between the roller shoe 10 and the roller shoe 10, but in that case, the same disadvantages as with the fixed shoe will occur, and the effect of using the roller shoe 10 cannot be obtained. In addition, when the length of the roller shoe 10 is approximately the same as that of the fixed shoe, the roller shoe 1
This results in insufficient axial strength against the thrust force acting on 0, and /
A total of 12 engineering units is required.

The first objective of the Seikan IM is to provide an inclined rolling mill that stably supports the raw tube during rolling with a compact convex structure and enables smooth rolling.

(1) In order to achieve the above objects, the inclined rolling mill according to the present invention has a drivable drive roller shoe having an entrance side angle and an exit side angle at a position adjacent to the rolling roll at a constant advance angle. It is arranged at an angle.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 6 is a side view showing an inclined rolling mill according to an embodiment of the present invention, and FIG. 7 is a front view showing a rolling state by the inclined rolling mill.

In this inclined rolling mill, two rolling rolls 21 are arranged on the left and right, and a plug 23 supported by a plugper 22 is arranged between both rolling rolls 21. The rolling roll 21 has an entrance side angle and an exit side angle, and is arranged inclined at an advance angle of, for example, 10 degrees to 12 degrees, and the trough 2
The circular saw piece 25 on 4 can move forward in the axial direction while rotating in the circumferential direction. In addition, the round steel piece 25 in the trough 2 is
While being guided by the cannon 26, it is pushed in by the pusher 27 and can be bitten by both rolling rolls 21.

Drive roller shoes 28 are arranged at two positions above and below between both rolling rolls 21. The drive roller shoe 28 has an entrance surface angle that reduces its outer diameter from its axial center toward its entry end, and also reduces its outer diameter from its axial center toward its exit end. It has an exit side angle that is radial.

Further, the drive shoe 28 is arranged so that its center axis is inclined at a constant advance angle of, for example, 3 to 4 degrees with respect to the axial direction of the raw pipe 29, and a velocity component along the forward direction of the raw pipe 29 is formed on the peripheral surface of the drive shoe 28. It is possible to obtain.

Further, the drive roller shoe 28 can be forcibly driven by a hydraulic motor 31 via a universal joint 30.

Next, - the operation of the above embodiment will be explained.

The round steel piece 25 on the trough 24 can be bitten by the rolling roll 21 under the push of the bushing 27, and further hits the plug 23 to be pierced and rolled. The bore-rolled blank tube 29 is enlarged in diameter to form a lower drive roller shoe 28.
comes into contact with. Here, the l-live roller shoe 28 is
It is forcibly driven at a speed higher than the circumferential speed of the rolling rolls 21, and therefore, even when the raw tube 29 is thin, the raw tube 2
9 will not escape between the drive roller shoe 28 and the rolling roll 21 and will not cause a sticker phenomenon. That is, generally the rolled blank pipe 29 is pulled in the tangential direction of the rolling rolls 21 and tries to escape into the gap between the rolling rolls 21 and the drive roller shoes 28; It rotates at a speed somewhat faster than the circumferential speed, and the base tube 29 is rotated by the drive roller shoe 28.
At this time, due to the friction between the blank tube 29 and the drive roller shoe 28, the blank v29 gains the circumferential speed of the drive roller shoe 28 and is brought to the opposite side of the rolling roll 21, resulting in a smooth rolling process. This makes it possible to perform rolling. This makes it possible to avoid the occurrence of the sticker phenomenon that occurs in the past when the raw tube escapes between the rolling rolls and the shoe and causes rolling to stop.

Further, since the drive roller shoe 28 has an entrance side angle and an exit side angle similarly to the rolling roll 21, it is prevented from coming into contact with the drive roller shoe 28 before the rolling roll 21 at the same shoe position. 1 to suppress the occurrence of the sticker phenomenon. In addition, since the drive roller shoe 28 is arranged at an angle with a constant advance angle, the slippage phenomenon is less than 10%, and the slippage phenomenon is smaller than that of conventional fixed shoes and disc shoes, resulting in good drilling efficiency. This makes it possible to shorten cycle time. If the sliding phenomenon is less than 10%, no sliding friction will occur, which will save the life of the show. Moreover, it becomes possible to obtain the raw pipe 29 without the shoe surface of the drive roller shoe 28 damaging the surface of the raw pipe 29.

In addition, in the above-mentioned inclined rolling mill, the drive roller shoes 28 are installed in the following manner. That is, the installation part of the drive roller shoe 28 is sandwiched between the rolling rolls 21, and there are a cannon 26, a universal joint for driving the JlfM roll, etc. on the inlet side, and a plug 23, and a plug 23 on the outlet side.
There are plug parser boats, etc., making it a very narrow space. Therefore, it is very difficult to mount the drive roller shoe 28 and its driving device in such a narrow space. However, when we investigate the worn parts of the currently used fixing shoes, we find that
As shown in the figure, it was observed that the part that actually comes into direct contact with the raw pipe is quite narrow. That is, as shown by L in FIG. 2, the minimum required length of the kite shoe can be about 2/3 of the conventionally required length even when the thickness of the original tube is thin. If the length of the drive roller shoe 28 is shortened in this way, even a thin shaft will have sufficient bending strength, and there will be no need for a backup roll as in the roller shoe IO shown in FIG. Since it is small, there is plenty of room for engagement with the cannon 26 on the entry side, making it easy to drive. In addition, as the drive roller shoe 28 and the universal joint 30 are connected, the engagement with the cannon 26 becomes difficult. By reducing the wall thickness of the portion adjacent to the cannon 26, it is possible to prevent buffering between the cannon 26 and the universal joint 30.

As described above, in the inclined rolling mill according to the present invention, a drivable drive roller shoe having an entrance side angle and an exit side angle is inclined at a constant advance angle at a position adjacent to the rolling mill. It is something. Therefore, the compact structure makes it possible to stably support the raw tube during rolling and to perform smooth rolling.

[Brief explanation of drawings]

Fig. 1 is a front view showing a fixed shoe in an inclined rolling mill, Fig. 2 is a side view showing the fixed shoe taken out from Fig. 1, Fig. 3 is a sectional view taken along the line ■-■ in Fig. 2, No. 41 Δ is a partially cutaway front view of a disc shoe in an inclined rolling mill, 5th Δ is a hemostasis diagram showing a roller shoe in an inclined rolling mill, and FIG. 6 is an inclined view according to an embodiment of the present invention. FIG. 7 is a side view showing the type rolling mill, and FIG. 7 is a front view showing the rolling state by the inclined type rolling mill. 21... Roll roll, 28... Drive roller shoe. Agent Patent Attorney Osamu Shiokawa Figure 1 Figure 2 Figure 3 Procedural Amendment (Voluntary) September 14, 1980 Commissioner of the Patent Office Manabu Shiga 1, Indication of Case 1988 Patent Application No. 175211 2 , Title of the invention Inclined rolling mill 3, Relationship with the case of the person making the amendment Patent applicant name Kawasaki Steel Corporation 4 Agent 105 Address No. 23 Mori Building 8, 23-7 Toranomon-chome, Minato-ku, Tokyo The entire text of the specification, Drawing 6, and contents of the amendment (1) The entire text of the specification is revised as in the attached revised specification. (2) Figures 5, 6, and 7 have been revised as shown in the attached sheet. To method 〇 Description 1, Name of the invention Inclined rolling mill 2, Claims (1) Inclined rolling mill in which rolling rolls having an entrance side angle and an exit side angle are arranged at an angle at a constant advance angle. In the V machine, a drivable roller shoe with an entrance side angle and an exit side angle [Q drive roller shoe] is arranged at a position adjacent to the rolling roll and inclined at a constant advance angle. Inclined rolling mill. L Giant 1, Kazuyasu's engineering - Masamasa. 3. Detailed Description of the Invention [Technical Field] The present invention relates to an inclined rolling mill used for manufacturing seamless steel pipes. [Background Art] Generally, in the process of perforating seamless steel pipes, two rolling rolls having an entry side angle and an exiting side angle are arranged at an angle at a constant advance angle, and a roller is fixed between the rolling rolls. - An inclined rolling mill equipped with guide shoes such as disc shoes or roller shoes is used. FIG. 1 is a front view showing a rolling roll 1, a plug 2, a blank tube 3, and a fixing shoe 4 in an inclined rolling mill. Base pipe 3
is pulled in the tangential direction by the circumferential speed of the rolling roll 1, collides with the fixed shoe 4, and slides. Therefore, the shoe surface of the fixed shoe 4 has a worn part 5A as shown in FIGS. 2 and 3. , 5B, yields 5. In addition, in FIG. 2, 5A shows a worn part when a thin-walled raw pipe is rolled, and 5B shows a worn part when a thick-walled raw pipe is rolled. Further, a fine rack is generated on the shoe surface of the fixed shoe 4, which is considered to be caused by thermal stress. Therefore, in an inclined rolling mill using the fixed shoe 4, rolling is frequently stopped in order to prevent the worn parts or cracks that occur on the shoe surface of the fixed shoe 4 from damaging the surface of the raw tube 3. It is necessary to clean the shoe surface of the fixed shoe 4 using a grinder or the like. However, the life of the fixed shoe 4 is short, and in order to improve these disadvantages even a little, the fixed shoe 4 is made of high-grade material with good wear resistance. is very large. FIG. 4 is a front view showing the disc shoe 6 in the inclined rolling mill. The disc shoe 6 is supported by a bearing 8 via a shaft 7 and can be driven by a drive motor 9. This disc shoe 6 has a diameter that is extremely large, reaching approximately 3 m, for example, in order to provide an appropriate surface for contacting the raw pipe 3, making the entire equipment long and difficult to apply to conventional equipment. It is impossible. Also,
Comparing the circumferential speed of the rolling rolls 10 and the advancing speed of the raw tube 3, it is approximately 6:1, and when using the disc shoe 6 that rotates in the direction of movement of the raw tube 3, the gap between the raw tube 3 and the disk shoe is approximately 6 to 1. 85% of cases occur due to slippage,
Inconveniences regarding the life of the disk shoe 6 and surface scratches on the raw tube 3 cannot be satisfactorily solved. Conventionally, when there is only one guide roller on each side in the roll gap direction as disclosed in JP-A No. 55-54203, a pipe enters the gap between the rolling roll and the guide roller, and the side part There were phenomena in which the tube became a concave square and could not be rotated, or the tube wall was torn. This is a phenomenon that is observed when idle rollers are used, and even when multiple roller shoes are inserted unevenly, their strength becomes a problem. According to the results of the experiment, the reaction force IH applied to the shoe changes depending on the shoe gap. FIG. 8 shows this relationship. The reaction force applied to the shoe is inversely proportional to the shoe gap when the shoe gap is less than a certain value, and is a constant value above a certain value. This constant value is about 20% of the reaction force applied to the rolling roll. Even if the number of roller shoes is increased, it is possible that only one roller will be in contact with the shell, so the reaction force will be as much as 30 tons. Since it is difficult to apply this strength to multiple rollers, JP-A-55-54203 adopts the support block system shown in Figure 2 or the backup roll system shown in Figure 3. I had no choice. FIG. 5 is a front view showing a roller shoe 10 in an inclined rolling mill as disclosed in Utility Model Application Publication No. 56-[509], and this roller shoe IO is an idle roller;
It rotates, but it is not forced to drive. Therefore, in this case, since the roller shoe 10 is an idle roller, when the raw tube 3 escapes into the gap between the rolling roll 1 and the roller shoe 10, the roller shoe 10 does not pull out the raw tube 3 and rolls the raw tube 3. may stop and cause staining. In order to prevent the above-mentioned sticker phenomenon from occurring,
A kite plate 11 is placed between the rolling roll 1 and the roller shoe 10.
It is also conceivable to insert a roller shoe IO, but in that case, the same problems as with a fixed shoe will occur, and the effect of using a roller shoe IO cannot be obtained. Further, if the length of the roller shoe 10 is made to be approximately the same as that of the fixed shoe, the shaft strength against the thrust force acting on the roller shoe 10 will be insufficient, and a backup roll 12 will be required. [Object of the Invention] An object of the present invention is to provide an inclined rolling mill that stably supports the raw pipe during rolling with a compact structure and enables smooth rolling. [Disclosure of the Invention] In order to achieve the above object, the present invention provides an inclined rolling mill in which rolls having an entrance side angle and an exit side angle are arranged at an angle at a constant advance angle. A pair of driveable drys with side angles. The blower shoe is arranged at an angle adjacent to the rolling roll so as to give a certain advance angle. [Embodiments of the Invention] Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 6 is a side view showing an inclined rolling mill according to an embodiment of the present invention, and FIG. 7 is a front view showing a rolling state by the inclined rolling mill. In this inclined rolling mill, two rolling rolls 21 are arranged on the left and right, and a plug 23 supported by a plugper 22 is arranged between both rolling rolls 21. The rolling roll 21 has an entrance side angle and an exit side angle, and is arranged inclined at an advance angle of, for example, 10 degrees to 12 degrees, and the trough 2
A four-tall round steel piece 25 can be moved forward in the axial direction while being rotated in the circumferential direction. Note that the round steel piece 25 of the trough 2L can be pushed into both rolling rolls 21 by being pushed by a pusher 27 while being guided onto the cannon 26. Drive roller shoes 28 are arranged at two positions above and below between both rolling rolls 21. The drive roller shoe 28 has an entrance surface angle that reduces its outer diameter from its axial center toward its entry end, and also reduces its outer diameter from its axial center toward its exit end. It has an exit side angle that is radial. Further, the drive roller shoe 28 is arranged so that its central axis is inclined at a constant advance angle of, for example, 3 to 4 degrees with respect to the axial direction of the raw pipe 29, and the drive roller shoe 28 is arranged so that its central axis is inclined at a constant advance angle of 3 to 4 degrees with respect to the axial direction of the raw pipe 29. It is possible to obtain the ingredients. According to experiments, when the advance angle of the shoe is less than 3 degrees, rolling defects such as stenica tend to occur, but when it exceeds 3 degrees, these problems are completely eliminated, and the larger the advance angle, the better the drilling efficiency. bring results. However, since the space is limited, there is a natural limit to the angle. Practically speaking, it is better to take the largest advance angle within the range that is permissible in terms of strength. Further, since the drive roller shoe 28 has an entry side angle and an exit side angle similar to the rolling roll 21, it is possible to prevent the drive roller shoe 28 from coming into contact with the driving roller shoe 28 before the rolling roll 21 at the same shoe position. This makes it possible to suppress the occurrence of the sticker phenomenon. In addition, drive roller shoe 2
8 is arranged at an inclination with a constant advance angle, so the slipping phenomenon is less than 10%, and compared to conventional fixed shoes and disc shoes, the slipping phenomenon is smaller, the drilling efficiency is better, and the cycle time is reduced. This makes it possible to shorten the time. When the slippage phenomenon is 10% or less, there is little occurrence of slipping friction, and the life of the shoe can be extended. Moreover, it becomes possible to obtain the raw pipe 29 without the shoe surface of the drive roller shoe 28 damaging the surface of the raw pipe 29. In addition, in the above-mentioned inclined rolling mill, the drive roller shoes 28 are installed as follows. That is, the installation part of the drive roller shoe 28 is sandwiched between the rolling rolls 21, and there is a cannon 26, a universal joint for driving the rolling rolls, etc. on the inlet side, and a plug 23, a plug par support, etc. on the outlet side. It is a very small space. Therefore, it is very difficult to install the drive roller shoe 28 and its driving device in such a narrow space. However, when we investigated the worn parts of the currently used fixing shoes, we found that the part that actually comes into direct contact with the raw pipe is quite narrow, as shown in FIG. 42. That is, as shown by L in FIG. 2, the minimum required length of the guide shoe may be about 2/3 of the conventionally required length even when the thickness of the raw pipe is thin. In this way, if the length of the drive roller shoe 28 is shortened, even a thin shaft will have sufficient bending strength, eliminating the need for a backup roll as in the roller shoe 10 shown in FIG. This also makes it easier to drive the cannon 26 on the inlet side, making it easier to engage with the cannon 26. In addition, with the connection between the drive roller shoe 28 and the universal joint 30, the cannon 26
Canon? If the diameter of the hole 6 is set to a value that barely allows the round steel piece 25 to pass through, and the wall thickness of the portion adjacent to the universal joint 30 is made thin, it is possible to prevent buffering between the cannon 26 and the universal joint 30. becomes. The shaft 44 of the drive roller shoe 28 is fixed by a receiver 32 and a support stand 33, and the base 43 of the support stand 33 is fixed with a wedge 34 using a pin 41 so that it can be easily removed. By rotating the screw shaft 45 by the hydraulic motor 39, moving the tapered table 37, and raising and lowering the lower frame 35, the upper surface position of the drive roller sheath j, -28 can be finely adjusted. Further, locking after adjustment is performed by hydraulic cylinders 42 (two pieces). Further, the drive roller shoe 28 can be forcibly driven by a drive device, such as a hydraulic motor 31, via a universal joint 30. The drive device may be an electric motor. Next, the operation of the above embodiment will be explained. The round steel piece 25 on the trough 24 can be bitten by the rolling roll 21 under the push of the bushing 27, and further hits the plug 23 to be pierced and rolled. The bore-rolled raw pipe 29 is enlarged in diameter and placed on the upper and lower 1.'' live roller shoes 28.
Hit 1 bottom. Therefore, drive roller shoe 28t±
, and is forcibly driven at a speed higher than the circumferential speed of the rolling roll 21. Therefore, even when the raw pipe 29 is thin, the raw pipe 29 is forced to move between the drive roller shoe 28 and the rolling roll 21.
There is no possibility that the force may escape between the two and cause a force phenomenon. That is, generally rolled raw pipe 29i and rolling roll 2
1 and tries to escape into the gap 1111 between the rolling roll 21 and the drive roller shoe 28, but the drive roller shoe -28it rolling roll 21
The raw tube 29 hits the drive roller shoe 28←, and due to the wear between the raw tube 29 and the drive roller shoe 28, the raw tube 29 t- The peripheral speed of the drive roller shoe 28 does not reach the same as the peripheral speed of the shoe 28, but rather the peripheral speed of the shoe 28 becomes the speed of the raw pipe 29. However, the shoe rotates at a speed (,% speed l,
), so the tangential force of the shoe is in the form of pulling the raw pipe. For this reason, the raw pipe is rolled by the rolling roll 21 on the opposite side (the rolling force is applied to the rolling roll 21), and the rolling force becomes smaller than the rolling force. This makes it possible to avoid the conventional sticker phenomenon in which the raw tube escapes between the rolling rolls and the shoe and causes rolling to stop. In addition, since the front end of the raw tube has already been rolled, no force in the axial direction of the raw tube acts, and the stress in the circumferential direction is high, which tends to expand the diameter and easily escape into the gap, causing flare. is likely to occur. Experiments have shown that there is a certain relationship between stick force generation, flare generation, and tangential force/shoe reaction force. Here, the shoe reaction force is the pressing force by the shell in the direction shown in FIG. This is the force in the B direction in the figure. According to the experimental results, as shown in FIG. 9, when the tangential force/shoe reaction force exceeds 3%, the occurrence of stick force and flare decreases rapidly. [Effects of the Invention] As described above, the inclined rolling mill according to the present invention has a drivable drive roller shoe having an entrance side angle and an exit side angle at a position adjacent to the rolling roll at a constant advance angle. It is arranged at an angle. Therefore, due to the compact structure,
It is possible to stably support the raw pipe during rolling and perform smooth rolling. In addition, since it can be extremely easily applied to existing inclined rolling mills, capital investment can be reduced, which provides great economic benefits. 4. Brief description of the drawings Figure 1 is a front view of the fixed shoe in an inclined rolling mill, Figure 2 is a side view of the fixed shoe shown in Figure 1 taken out, and Figure 3 is the same figure as shown in Figure 2. ■A sectional view taken along the line, Figure 4 is a partially cutaway front view of a disc shoe in an inclined rolling mill, Figure 5 is a front view of a roller shoe in an inclined rolling mill, and Figure 6 is a front view of the present invention. FIG. 7 is a side view showing the inclined rolling mill according to one embodiment, FIG. 7 is a front view showing the rolling state by the inclined rolling mill, and FIG. 8 shows the shoe gap and shoes when a plurality of roller shoes are arranged. FIG. 9 is a diagram showing the relationship between tangential force/shoe reaction force, stick force generation rate, and flare generation rate. 21...Rolling roll, 28...Drive roller shoe 0 Agent: Patent attorney Osamu Shiokawa

Claims (1)

[Claims] (1) In an inclined rolling mill in which rolling rolls each having an entrance side angle and an exit side angle are arranged at an inclined angle at a constant advance angle, a drivable drive roller shoe having an entrance side angle and an exit side angle is rolled. An inclined rolling mill characterized by an inclined rolling mill arranged adjacent to the rolls at a constant advance angle.