JPH0547288B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to an apparatus for tilting tubes.

[Prior Art] Generally, in the process of perforating seamless steel pipes, as shown in FIG. An inclined rolling mill 3 having fixed shoes 2 arranged therein is used. In addition, 4 is a plug, 5
is a raw pipe.

The fixing shoe 2 prevents the raw pipe 5 from coming out of the rolling area and determines the outer diameter of the raw pipe 5. However, the fixed show 2
Since it is in full sliding contact with the raw pipe 5 as the material to be rolled, it is subjected to great thermal stress and frictional force, and is made of a high-grade material that is heat and wear resistant and contains a large amount of chromium and nickel. Nevertheless,
The occurrence of cracks and abrasion is significant, and the friction between the fixed shoe 2 and the raw tube 5 tends to cause seizure, and as a result, outer surface scratches called shoe marks occur on the surface of the raw tube 5, which deteriorates the quality and properties of the raw tube 5. deteriorate. In addition, in the above-mentioned inclined rolling mill 3, in order to prevent the occurrence of shoe marks, it is necessary to stop the rolling mill and take care of the burned-out portion of the fixed shoe 2 or replace the fixed shoe 2. This is causing the rate to decline.

Therefore, in order to eliminate the inconvenience caused by the use of the above-mentioned fixed shoe,
As shown in No. 56-40801 and Japanese Patent Publication No. 58-48243, on both sides of the rolling area formed by both rolling rolls,
Incline rolling mills each having two or more roller shoes have been proposed. However, in the case of the above-mentioned conventionally proposed inclined rolling mill, four or more roller shoes are installed in an extremely narrow space, so the diameter of the roller shoe becomes narrow and the reaction during rolling is reduced. It is difficult to provide the roller shoe with the strength to withstand the force.

In addition, in order to reinforce the roller shoe in the inclined rolling mill, the inclined rolling mill 6 shown in FIG.
It is necessary to support the roller show 7 from the back by a back-up roll 8 as shown in FIG. be. However, during rolling by these inclined rolling mills 6 and 9, the scale adhering to the material billet and the tube 5 is scattered, and this scattered scale is between the roller shoe 7 and the back-up roll 8 or the back-up block 10. There is a risk that the roller shoe 7 may become stuck between the rollers and the roller shoe 7 may become unable to rotate.

In addition, as in the inclined rolling mill 12 shown in FIG. When 〓 is large and the raw pipe 5 as the material to be rolled is thin-walled, the flare at the tip or rear end of the raw pipe 5 is caused by the rolling roll 1, as shown by the two-dot chain line in FIG. There is an inconvenience that the roller protrudes outward from between the roller shoe 11 and the roller shoe 11, resulting in a state where rolling becomes impossible.

[Problems to be Solved by the Invention] The present invention provides stable support for the raw pipe during rolling using simple equipment without deteriorating the surface properties in the steady rolling section of the raw pipe, and also provides a stable support for the raw pipe at the tip end of the raw pipe. It is an object of the present invention to provide an inclination rolling device for a tube that prevents the flare at the rear end from protruding outside the rolling area and making rolling impossible.

[Means for Solving the Problems] The present invention provides a method in which a pair of rolling rolls are arranged at an angle, and one roller shoe is arranged on each side of the rolling area of the raw pipe formed by the two rolling rolls,
A pipe inclination rolling device comprising a guide member disposed between each roll and a roller shoe located in the direction of rotation of each roll with respect to the rolling area, the guide member being It is arranged in such a position that it does not come into contact with the mother tube when rolling the central portion, and can come into contact with the mother tube when rolling the tip and rear end portions of the mother tube.

[Function] In the inclination rolling apparatus of the present invention, when the amount of flare of the tip and rear end of the raw pipe is a, and the amount of flare of the central part, which is the steady rolling part of the raw pipe, is b, This was done by focusing on the fact that b is extremely small compared to a because the center part is restrained by the front and rear raw pipe materials. The guide members for the leading end and the trailing end are arranged at positions where they do not need to be prevented from extruding and do not come into contact with the steady rolling part of the raw pipe where the surface quality is desired to be good. Therefore, the present invention has the following effects.

The center portion of the raw tube, which is the steady rolling portion, is stably supported by a pair of roller shoes without contacting the guide member. At this time, since the central portion of the raw pipe has a small overhang, there is no need to contact the guide member to prevent the central portion from protruding, and since there is no contact with the guide member, the surface quality cannot be deteriorated.

The flares at the tip and rear ends of the raw tube have a large overhang and tend to protrude outside the rolling area, but they come into contact with the guide member and are prevented from protruding. Note that the flare is a portion that is discarded as a crop, and there is no problem even if the surface quality deteriorates due to contact with the guide member.

With the above, simple equipment can stably support the raw pipe during rolling without deteriorating the surface properties of the raw pipe, and the flares at the tip and rear ends of the raw pipe protrude outside the rolling area, making rolling impossible. It is possible to obtain a tube inclination rolling device that can prevent this from occurring.

[Detailed Description of the Invention] A mother pipe is produced by an inclined rolling mill comprising a pair of rolling rolls arranged at an angle, and a pair of roller shoes arranged on both sides of the rolling region of the raw pipe formed by the two rolling rolls. When rolling 5, t/D of raw pipe 5
(where t is the wall thickness and D is the diameter), the flare at the tip or rear end of the raw tube 5 (see Figure 6) will buckle as shown by the two-dot chain line in Figure 5. , the buckled portion of the raw pipe 5 protrudes between the rolling roll 1 and the roller shoe 11, and rolling stops.

In order to prevent the flare from protruding, the inclined rolling mill 13 according to the present invention is equipped with a roller shield positioned in the direction of rotation of each rolling roll 1 and the rolling area of each rolling roll 1, as shown in FIG. A guide plate 14 as a guide member is provided between the user 11 and the user 11.
.

Incidentally, Japanese Utility Model Application No. 56-60507 discloses an inclined rolling mill in which a pressing plate 15 is disposed between the rolling roll 1 and the roller shoe 7, as shown in FIG. In this inclined rolling mill, the blank tube 5 and the holding plate 15 are in constant contact while rolling the blank tube 5, and the purpose of installing the roller shoe is (1) to eliminate sliding friction with the rolled material. (2) It is not possible to prevent external scratches called shoe marks, and (3) it is not possible to extend the life of the shoe.

On the other hand, the guide plate 14 provided in the inclined rolling mill 13 of the present invention is different from the holding plate 15 of the inclined rolling mill according to the above-mentioned Utility Model Application Publication No. 56-60507. without touching the tube 5,
It is arranged at a position where it can come into contact with the raw pipe 5 during rolling of the tip and rear ends of the raw pipe 5.

That is, in FIG. 1, in order to investigate the deformed shape of the raw pipe 5, the rolling mill was stopped while the central part (excluding the tip and rear ends) of the raw pipe 5 was being rolled by the actual machine. This is a cross-sectional print of the obtained raw tube 5.
On the other hand, FIG. 8 is a cross-sectional print of a raw pipe 5 obtained by rolling the tip and rear end parts of the raw pipe 5 using an actual machine not equipped with the inner plate 14 according to the present invention. The raw pipe 5 has a flare protruding due to plastic deformation at the tip and rear ends. According to the comparison of the deformed state of the raw pipe 5 in FIG. 1 and FIG. When the tube 5 plastically buckles and tries to protrude, the guide plate 14 can be placed at a position where the plastic buckling can be prevented, and the present invention has the guide plate 14 placed at such a position. be.

Example: The position where the guide plate 14 should be placed is t/D of the raw pipe 5.
(t is the wall thickness of the raw pipe 5, D is the outer diameter of the raw pipe 5), and varies depending on conditions such as material. According to our experiments, when the material of the base pipe 5 is ordinary steel and the t/D is 6 to 8%, as shown in Fig. 9, it should not come into contact with the rolling roll 1 It should not come into contact with the roller shoe 11 Pass A circle centered on a line and given by radius R=H/2+k×1/t. However, H is roller show 1
It is desirable to install the guide plate 14 within a region 16 determined by an interval of 1 and k is a constant (185 to 225). If k is made large, the purpose of the guide plate 14, which is to eliminate the protrusion of the flare at the leading and trailing ends, cannot be achieved, and if k is made small, the guide plate 14 contacts with the guide plate 14 over the entire length of the raw pipe 5, This causes wear of the guide plate 14 or a show mark on the raw tube 5. Therefore, k must be carefully selected in consideration of conditions such as the material t/D of the raw pipe 5 and the temperature.

Note that when the guide plate 14 is arranged as described above, the guide plate 14 is placed at the tip and rear end of the raw pipe 5.
There is a risk that a show mark may occur due to contact with 4. However, the length of this show mark is about 150 mm at most, and it is usually cut off in a subsequent process and is not part of the product, so even if a show mark occurs in this part, it will not cause any inconvenience. In addition, the guide plate 14 comes into contact with the raw pipe 5,
Although it is subjected to thermal stress and frictional force, the contact time is about 0.1 seconds at most, which is extremely short compared to the contact time of about 10 seconds for the conventional fixed shoe 2, and it also causes problems with damage and wear of the guide plate 14. There is no.

As described above, the guide plate 14 is connected to each rolling roll 1.
and a roller shoe 11 located in the direction of rotation relative to the rolling region of each roll 1, it is possible to manufacture thin-walled tubes that are difficult to manufacture with conventional rolling mills having a pair of roller shoes. It becomes possible to manufacture easily. In the embodiment described above, only a pair of guide plates 14 are installed, but it is also possible to install guide plates on both sides of the roller shoe, thus installing two pairs of guide plates.

[Effects of the Invention] As described above, the present invention includes a pair of rolling rolls arranged at an angle, and one roller show arranged on each side of the rolling area of the raw pipe formed by the two rolling rolls, A pipe inclination rolling device comprising a guide member disposed between each roll and a roller shoe located in the direction of rotation of each roll with respect to the rolling area, the guide member being It is arranged in such a position that it does not come into contact with the mother tube during rolling of the central portion, but can come into contact with the mother tube during rolling of the tip and rear end portions of the mother tube. Therefore, with simple equipment, it is possible to stably support the raw pipe during rolling without deteriorating the surface quality in the steady rolling area of the raw pipe, and to ensure that the flares at the tip and rear ends of the raw pipe are outside the rolling area. It is possible to obtain a tilt rolling device for a tube that prevents the tube from protruding and becoming unable to be rolled.

[Brief explanation of drawings]

FIG. 1 is a front view showing main parts of an inclined rolling mill according to an embodiment of the present invention, FIG. 2 is a front view showing main parts of a conventional inclined rolling mill, and FIG. 3 is a front view showing main parts of a conventional inclined rolling mill. FIG. 4 is a front view showing the main parts of another conventional inclined rolling mill; FIG. 5 is a front view showing the main parts of another conventional inclined rolling mill; FIG. 6 Fig. 7 is a front view showing the main parts of another conventional inclined rolling mill, and Fig. 8 shows the flare that occurs in the conventional inclined rolling mill. FIG. 9 is a front view showing the flare of the raw pipe, and FIG. 9 is a front view showing the installation area of the guide member in the present invention. 1... Roll roll, 11... Roller shoe,
14... Information board.

Claims (1)

[Claims] 1 A pair of rolling rolls are arranged at an angle, and
One roller shoe is arranged on each side of the rolling area of the mother pipe formed by the above-mentioned two rolling rolls, and each rolling roll is connected to a roller show located in the direction of rotation of each rolling roll with respect to the rolling area. An apparatus for inclined rolling of pipes in which a guide member is arranged between the pipes, the guide member not touching the center part of the pipe when rolling the center part of the pipe, and rolling the guide member between the tip and rear ends of the pipe. An inclined rolling device for tubes, which is arranged at a position where it can come into contact with the raw tube during rolling.