JPH02200302A - Method for rolling straight type steel sheet pile and rolling mill train thereof - Google Patents

Abstract

PURPOSE:To allow selective formation of web thicknesses, joint part thicknesses and effective widths to arbitrary sizes by providing a pair of upper and lower helical rolls adjustable in width in the direction orthogonal with a rolling direction between an intermediate rolling stage and a finish rolling stage. CONSTITUTION:An ingot 10 having a rectangular or dogbone shape in section as a stock is rolled to a roughly molded material by a breakdown mill BD in the roughing stage as the method for rolling a straight type steel sheet pile 5. The molded material is then rolled by intermediate universal mills R1, R2 and edger mills E1, E2 to intermediate rolled stocks 15, 16 having an approximately H section in the intermediate stage. Finally, the flange parts of the intermediate rolled stocks 15, 16 are curved or shaped by vertical horizontal rolls to form the joint parts 18, 19 in the finish rolling stage. A pair of the upper and lower helical rolls 45, 46 which come into contact with the inner side of the flanges of the intermediate rolled stocks 15, 16 and the axial centers of which have the prescribed axial angle alpha with the plane orthogonal with the horizontal plane of the rolling direction are provided adjustable in width in the rolling direction between the above-mentioned intermediate stage and the finish rolling stage.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a method for manufacturing straight steel sheet piles by rolling and a rolling equipment train for the method.

[Conventional technology]

The most typical shape example of the straight steel sheet pile 5 targeted by the present invention is shown in FIG. It has a female joint 5b with a wall thickness Tr that opens in the direction, and has a male joint 5c formed at the other end in a size that fits into the space of the female joint 5b. Note that the center distance HiW between the female joint 5b and the male joint 5c is referred to as an effective width. FIGS. 9(a) and 9(b) show other product shape examples of straight steel sheet piles, in which group (a) is a left-right asymmetric type, and group (b) is a left-right symmetric straight steel sheet pile. Group (a) (1) to (8) have a male joint on the left and a female joint on the right. Furthermore, (a)
Among the groups, (7) and (8) are formed into a male joint by crushing only one (left) joint part after shaping them bilaterally symmetrically.

In group (b), (1) is a female joint, and male joints (2) to (9) are used in combination with this female joint. The common uses of these straight steel sheet piles are
As shown in Figures (a) and (b), a plate 2 is welded to a web 1 of two straight steel sheet piles to form a member with an H-shaped cross section, and is used as a so-called box-shaped steel sheet pile. In addition, the 10th
Figure (a) is an example of a left-right asymmetric type, and Figure (b) is an example of a left-right symmetric type.

The characteristics of this box-shaped steel sheet pile are: ■ It has excellent cross-sectional performance, so the wall thickness can be made thin; The zero surface is smooth, so it is suitable for wall functions; ■ It is easy to form a composite structure with concrete. Specific uses include continuous walls for earth retention, foundation piles, shear walls for permanent construction, and deep foundation piles for landslides. Depending on the application, H-shaped steel sheet piles 3 may be connected with one symmetrical straight steel sheet pile 4 as shown in Fig. 11(a), or they may be used as shown in Fig. 11(b).
), a structure in which H-shaped steel sheet piles 3 are connected to symmetrical box-shaped steel sheet piles is also used.

By the way, straight steel sheet piles, which are the basic components of the box-type steel sheet piles mentioned above, have become mainstream in recent years due to the active development trend of underground spaces, and construction work in urban areas has become mainstream, and the emphasis has been placed on ease of construction. Improvements in fitting fitability are required, and providing a product series with various cross-sectional properties has become an important issue.

The so-called caliber rolling method shown in FIG. 12 is well known as a general conventional manufacturing method for straight steel sheet piles. In the same figure, the rough shaped steel billet BB is a material made in a blooming factory or a foundry, and this material BBt- is successively rolled in each hole from 13 to 1 to form a product, but this method is Since the rolling is mainly based on the grinding action of the side walls of the upper and lower rolls, the closed hole type (C1osed Pa5s) is an essential component of the groove series. For this reason, the amount of roll modification due to hole shape wear is large, and the roll consumption rate is high.In addition, large amounts of rolling oil and roll cooling water are required, and if this is insufficient, the shape of the joint part of the product will be unstable. This makes rolling work extremely difficult. Moreover, since there are many holes, a long roll body length is required, and it is difficult to manufacture wide straight steel sheet piles with a large effective width W.

As a solution to this problem, there is a so-called universal rolling method disclosed in Japanese Patent Publication No. 47-47784, which is a rolling method that eliminates forming defects by applying direct reduction to the material portion forming the joint.

A typical example of this universal rolling method is shown in Fig. 13, and by introducing the universal rolling method in 4-1.2.3 in the intermediate rolling section, it is possible to make the material into a rectangular steel billet SL. . In addition, in Japanese Patent Publication No. 58-38241, the finishing universal rolling method is also applied to the finishing hole mold 1, and the hole width of the left and right joints is regulated by vertical rolls inserted into the left and right joints, thereby reducing the variation in the hole width of the joints. Means for suppression are also well known.

However, even with this method, relatively deep and complicated holes are required for the upper and lower horizontal rolls, and the above-mentioned problems cannot be solved.

Another measure was to change the shape of the straight steel sheet pile to a product shape that is easier to roll, and to improve the rolling process by using so-called universal rolling equipment for H-section steel and using a method similar to the rolling method for H-section steel. There is. The technique disclosed in Japanese Patent Publication No. 55-11921 shown in FIG. 14 and the technique disclosed in Japanese Patent Application Laid-open No. 1987-1913 shown in FIG. 15 are examples of this. Although the problem has been solved, the target is the manufacture of straight steel sheet piles with a specific effective width W, and the separation of web thickness Tw and joint thickness T is very narrow due to modeling constraints. There was a problem that the range had to be limited.

(Problems to be Solved by the Invention) The present invention enables the production of straight steel sheet piles by rolling the web thickness T without causing joint shape defects, bending during rolling, reduction in roll consumption, etc.・Provides a means that allows the joint thickness TF and effective width W to be made into any desired size according to the purpose of the application, and further utilizes the existing H-shaped steel universal rolling equipment row as much as possible. The purpose of this project is to manufacture straight steel sheet piles with minimal new installation or modification of equipment.

[Means to solve the problem]

The present invention relates to a rough rolling process equipped with a breakdown mill that rolls a rough shaped material using a steel billet with a rectangular or dogbone-shaped cross section as a raw material, and a universal rolling process that rolls the rough shaped material into an intermediate rolled material with a substantially H-shaped cross section. In a method of rolling a straight steel sheet pile by an intermediate rolling process comprising a mill and an edger mill, and a finishing rolling process comprising upper and lower horizontal rolls that curve or shape the flange part of the intermediate rolled material to form a joint part, the intermediate rolling process comprises: Between the rolling process and the finish rolling process, a pair of upper and lower oblique rolls are provided which are in contact with the inside of the flange of the intermediate rolled material and whose roll axes are at a predetermined angle α with respect to a plane perpendicular to the horizontal plane in the rolling direction. and a method for rolling a straight steel sheet pile, in which the width is adjustable in a direction perpendicular to the rolling direction, and the diagonal roll widens the inner width between the left and right flanges of the intermediate rolled material, and the flanges are tilted outward. be.

In addition, in the finish rolling process, a vertical roll having a flange protruding from the circumference of the horizontal roll is rotatably provided on the side of the horizontal roll, and the tip of the flange is brought into contact with the bottom of the hole in the part corresponding to the joint of the material to be rolled. A method for rolling a straight steel sheet pile in which the material to be rolled is guided by rolling, and the edger roll in the intermediate rolling process and the horizontal roll in the finishing rolling process are variable in body width, and the effective width and thickness can be arbitrarily set with the same roll set. This is a rolling method for straight steel sheet piles.

The equipment train of the present invention consists of one or more intermediate rolling mills including a rough rolling mill having a breakdown mill with upper and lower rolls, a universal mill having upper and lower horizontal rolls and a vertical roll, and an edger mill having upper and lower horizontal rolls with variable body widths. In the rolling process, a pair of upper and lower oblique rolls whose roll axes are at a predetermined angle α with respect to a plane perpendicular to the horizontal plane in the rolling direction are provided, and the width can be adjusted in the direction perpendicular to the rolling direction.
It is a rolling equipment row of straight steel sheet piles in which an inclined rolling process and a finish rolling process equipped with upper and lower horizontal rolls with variable body widths are arranged in order, and there is also a rolling equipment row on the body circumference on either side or one of the upper and lower horizontal rolls in the finish rolling process. This is a rolling equipment row for straight steel sheet piles equipped with rotatable vertical rolls with seven protruding flange.

[Function/Example]

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

FIG. 1 is an explanatory diagram showing an example of a rolling method when the present invention is applied to manufacturing a left-right asymmetric straight steel sheet pile, and FIG. 2 is an explanatory diagram showing an example of the arrangement of rolling stands.

In the figure, in the rough rolling process, a thin-walled slab or a dog-bone shaped steel billet is subjected to multiple etchings using upper and lower horizontal rolls 11a and 11b of a breakdown mill BD, and processed into a rough-shaped steel billet 10 in a dog-bone shape. This is the process of Note that the hole shape of the upper and lower horizontal rolls lla and llb is larger than the hole bottom width S of the upper horizontal roll lla, which molds the male joint part, than that of the lower horizontal roll 1lb, which molds the female joint part.
O hole bottom width S.

A central convex portion P is provided at the bottom of the hole in order to make it larger and to facilitate widening of the portion corresponding to the flange in the next step.

Next, the rough shaped steel piece 10 is cut into a first rough universal mill R1.
The process of rolling and shaping into an intermediate rolled material 15 having an approximately 11-shaped cross section by means of the first edger mill E1, the second rough universal mill R2, and the second edger mill E2 is the intermediate rolling process. Here, horizontal roll 2 of universal mill R1, R2
0a, 20b, 21a.

21b uses an existing roll for H-shape rolling, and vertical rolls 31a, 31b, 32a, and 32b similarly incorporate flat vertical rolls used in a finishing universal mill F for H-shape rolling. is valid. In this way, the wall thickness of the joint part of the straight steel sheet pile becomes thick at the base and thin at the tip, and the use of flat vertical rolls reduces web deviation and flange wall thickness deviation of the intermediate rolled material 15, Dimensional precision can be dramatically improved compared to normal °H type copper tone rolling. In addition, the horizontal rolls 41a, 41b, 4 of Edger Mill El
2a, 42b and horizontal roll 43a of E2,
If 43b, 44a, and 44b are split rolls whose body widths can be arbitrarily changed, it is advantageous because intermediate rolled materials of various sizes with different web heights can be obtained without changing the rolls in the intermediate rolling process. Of course, in the present invention, it is possible to change the web height within a certain range by performing the width widening/slope forming process described later without using a variable body width roll. In addition, the second coarse universal mill R2 and the second
Horizontal rolls 21a, 21b of Edger Mill E2.

43a, 43b, 44a, and 44b, in consideration of the subsequent widening and rolling in the inclined forming mill R3, thickened surplus parts 81 and 82 are provided on both sides of the web depending on the range of the width widening amount. It is desirable to set this.

In the widening/tilting forming mill R3, the inner web width WI of the finish rolling mill material 16 is changed so that the inner web width W0 of the intermediate rolled material 15 obtained in the second edger mill E2 becomes the required hot product effective width W. Expand to. Here, the hot product effective width W,
is a value determined by taking into account the shrinkage allowance due to hot rolling and the dimensional change due to groove rolling action for the product effective width W, and W+ is determined by considering the dimensional change of the material due to bending and forming rolling in the finishing mill F. This is the setting value. W is a value appropriately selected and appropriated from the series of horizontal rolls of the existing universal mill for rolling H-shaped steel. In the widening and tilting forming mill R3, in addition to this web widening adjustment rolling, a pair of upper and lower oblique rolls 45a, 45b, 46a are used.

The roll axis angle α of 46b is set. This axis angle α
is the angle between the axial center of the oblique roll and the plane perpendicular to the horizontal plane in the rolling direction, and by appropriately setting this angle α and the roll interval, the flange of the intermediate rolled material 15 can be bent outward and the flange can be tilted. Carrying out rolling to increase the angle θ1 and setting the inverted angle β of the skew roll axis with respect to the horizontal plane further enhances the widening effect and prevents scratches on the inside of the flange caused by the skew roll. , the flange inclination angle θ of the intermediate rolled material 15, which may be adopted as necessary. It is sufficient that the angle is 6 to 8 degrees, which is the same as when rolling an existing H-shaped steel, and this is increased to an angle θ, which is appropriate for finish bending in the widening/tilting forming mill R3. Note that this angle θ,
As a result of experiments, it was found that the angle should be set within the range of 15 to 45 degrees.

That is, if the angle is less than 15 degrees, it becomes a severe condition for the curve forming of the joint part in the subsequent finish rolling process, resulting in problems such as poor biting, poor shape, or the bottom of the roll hole. - On the other hand, if the angle exceeds 45 degrees, smooth bending cannot be performed in the joint forming hole die in the finish rolling process.

In finishing universal mill F, widening/sloping forming mill R3
The pre-finished material 16 formed in the above process is subjected to final bending processing to obtain a hot product 17 with high dimensional accuracy.

Now, in the case of asymmetrical straight steel sheet piles, if you use the upper and lower double rolls that are common in finishing rolling mills, the female joint part 19
Since the deformation degree of the male joint part 18 is greater than that of the male joint part 18, a slight difference in stretching occurs, and the rolled material 17 tends to bend on the rolling exit side toward the female joint part 19, which is less stretched, so this is prevented. There is a need. Also, the material 16 is properly rolled into the horizontal roll 47.
a, 47b.

It is necessary to guide the rolled material to the groove positions 48a and 48b, but since the rolled material changes greatly in the horizontal width direction due to the bending process with the rolls, if you try to restrict the bending by tightening the restraint of the exit guide, the rolled material 17 The shape of the joint will be deformed and the shape will be defective. Therefore, in order to develop the most appropriate guide system, the present inventors have developed a hole bottom Q (hereinafter simply referred to as hole bottom Q) at a part corresponding to the female joint of the rolled material, where the relative position of the rolled material is small, as shown in Fig. 5. A hot rolling test was conducted by inserting a plate guide 50 penetrating the front and rear surfaces through the opening. As a result, it was found that if the constraint of the hole bottom Q was strengthened, it would be difficult to obtain a suitable material, and seize-like scratches would occur in the hole bottom Q of the rolled material 17.

Based on this knowledge, the present invention solves the above problem by providing vertical rolls 33 on the sides of the finishing horizontal roll. That is, as shown in the finish rolling process F in FIG.
3a is provided in a protruding manner, and the side surface of this flange 33a is set so as to contact and follow the edge surfaces of the horizontal rolls 48a and 48b, and the flange 33a is inserted into the female joint opening of the material to be rolled, and the flange 33a is inserted into the hole bottom. The tip of the flange 33a is provided in contact with Q. In addition, as shown in FIG. 2, the axis position of the vertical roll 33 is as shown in FIG.
The rolled material 17 is effectively prevented from being bent on the rolling exit side by being set to be displaced by C toward the exit side in the rolling direction from the axis 0H08 of b. With this configuration, the vertical rolls 33 rotate in synchronization with the advancing speed of the rolled material 17, so that problems such as scratches and seizure do not occur.

The web thickness Tw of the straight steel sheet piles is sized by adjusting the roll of the horizontal rolls, and the joint thickness TF is sized by adjusting the roll of the vertical rolls 31, 31', 32, and 32'.

Here, since the dimensions and shape of the upper and lower halves of the joint parts 18 and 19 of the product are the same for all series, in the end, the special rolls for manufacturing the left-right asymmetric linear steel sheet piles are BD, El, R2, R3. , one set of each horizontal roll of the F mill and one set of the vertical roll of the F mill is sufficient. Furthermore, in the case of symmetrical straight sheet piles, if the joint shape is determined appropriately, the rolls of BD, El, R2, and R3 mills can also be used in common with the existing roll series for rolling H-section steel, so in the end, only the F mill rolls are dedicated rolls. You can prepare it as

FIG. 3 is an explanatory diagram when rolling a linear steel sheet pile having a thicker web thickness Tw in the finish rolling process. In this case, if the distance between the upper and lower horizontal rolls is increased, the axis will be O-0.
The male joint part 18 has an open shape, but it is suitable for the continuous wall construction method in which cement milk is injected from the joint space P to improve water-stopping performance as shown in Fig. 4. In fact, this is actually a good thing for the product.

In addition, in the above example, the intermediate universal mill group is R1, El
Although there are two groups, R2 and R2, it is of course possible to have one group, and the method and apparatus of the present invention can be applied to any factory that generally performs universal rolling of H-section steel.

FIG. 6 shows an example in which a straight steel sheet pile produced according to the present invention is used as a box-shaped steel sheet pile, and this is used as a circular cell. That is, by selecting the outer effective width W and the inner effective width W of the straight steel sheet pile to arbitrary values determined from the design conditions, the joint can be set to a loose fitting state, and the workability is significantly improved. be able to.

Moreover, FIGS. 7(a) and 7(b) show one or more protrusions formed on the web portion of a straight steel sheet pile manufactured by the present invention using horizontal rolls, as shown in FIG. 7(C). The welding position when forming a box-shaped steel sheet pile via the plate 2 can be easily determined, and the work is also simplified.

〔Effect of the invention〕

According to the method and equipment train of the present invention, the existing H-beam universal rolling equipment train is utilized as much as possible, and web thicknesses T of multiple sizes can be achieved with the same roll set.・Since the joint thickness T and effective width W can be made into economical desired sizes according to the construction project, the number of rolling rolls and their accessories required is drastically reduced, and the roll consumption rate is improved. There are significant production benefits, such as a reduction in the number of roll changes, which improves operating efficiency and reduces the need for personnel to change the rolls, as well as consolidating the size of the materials used.

In addition, high-quality straight steel sheet piles with stable joint shapes and excellent workability can be manufactured efficiently even in small lots.
We can respond quickly and accurately to the current diversifying market needs.

[Brief explanation of the drawing]

Fig. 1 is a schematic front view showing the rolling sequence according to one embodiment of the present invention, Fig. 2 is an explanatory diagram showing the rolling process according to one embodiment of the present invention, and Fig. 3 is a thick web straight steel according to the present invention. FIG. 4 is an explanatory diagram showing an example of the fitting situation of straight steel sheet piles according to the present invention; FIG. 5 is a schematic diagram illustrating the test of the guide structure according to the present invention; FIG. 6 and Fig. 7 is an explanatory diagram of the usage state of the straight steel sheet pile manufactured by the present invention, Fig. 8 is a schematic cross-sectional diagram illustrating the shape of the straight steel sheet pile, and Fig. 9
The figures are schematic cross-sectional views of straight steel sheet piles with various cross-sectional shapes manufactured according to the present invention. Figures 1O and 11 are explanatory diagrams showing usage examples in which the straight steel sheet piles manufactured according to the present invention are formed as box-shaped steel sheet piles. Figure 12 is an explanatory diagram showing the method of rolling symmetrical straight steel sheet piles using the conventional groove rolling method. Figure 13 is a symmetrical straight steel sheet pile in which the universal rolling method is applied to a part of the conventional groove rolling method. An explanatory diagram showing the rolling method of sheet piles. Figure 14 is an explanatory diagram showing the rolling method of asymmetrical straight steel sheet piles using the conventional universal rolling method. Figure 15 is an explanatory diagram showing the rolling method of symmetrical straight steel sheet piles using the conventional universal rolling method. An explanatory diagram showing the rolling method'. BD... Breakdown mill, El, El... Edger mill, R+, Rs... Intermediate universal mill, R3... Widening/slope forming mill, F... Finishing rolling mill, 11a, llb. ... Breakdown mill upper and lower horizontal rolls, 41a + 41b, 42a, 42b Zjer mill upper and lower horizontal rolls, 20a, 20b... First intermediate universal mill upper and lower horizontal rolls, 31a, 31b... First intermediate universal mill vertical rolls , 21a, 21b...Second intermediate universal mill upper and lower horizontal rolls, 32a, 32b...Second intermediate universal mill vertical rolls, 43a, 43b, 44a, 44b...
Edger Mill upper and lower horizontal rolls, 45a, 45b, 46a, 46b--diagonal rolls, 47a, 47b, 48a, 48b--
- Finishing rolling mill upper and lower horizontal rolls, 5... Straight steel sheet piles, 33... Vertical rolls, 1
0...Rough shaped steel piece, 18, 19...Joint part. 15, 16... intermediate rolled material,

Claims (1)

[Scope of Claims] 1. A rough rolling process equipped with a breakdown mill that rolls a rough shaped material using a steel billet with a rectangular or dogbone-shaped cross section as a raw material, and the rough shaped material is an intermediate rolled material with a substantially H-shaped cross section. In a method of rolling a straight steel sheet pile by an intermediate rolling process comprising a universal mill and an edger mill that roll the material, and a finishing rolling process comprising upper and lower horizontal rolls that curve or shape the flange part of the intermediate rolled material to form a joint part, Between the intermediate rolling process and the finishing rolling process,
A pair of upper and lower oblique rolls that are in contact with the inside of the flange of the intermediate rolled material and whose roll axes have a predetermined axis angle α with respect to a plane perpendicular to a horizontal plane in the rolling direction, and are arranged in a direction perpendicular to the rolling direction. The width can be adjusted, and the inner width between the left and right flanges of the intermediate rolled material is widened by the skew roll, and
A method for rolling straight steel sheet piles, characterized by slanting flanges outward. 2. In the finishing rolling process according to claim 1, a vertical roll having a flange protruding from the circumference of the body is rotatably provided on the side of the horizontal roll, and the tip of the flange is provided at the bottom of the hole in the part corresponding to the joint of the material to be rolled. A method for rolling a straight steel sheet pile, characterized in that the material to be rolled is guided by bringing the parts into contact with each other. 3. Claim 1 characterized in that the edger roll in the intermediate rolling process and the horizontal roll in the finish rolling process have variable body widths so that the effective width and thickness can be arbitrarily differentiated from the same roll set.
Or the method of rolling a straight steel sheet pile according to claim 2. 4. One or more intermediate rolling processes consisting of a rough rolling process with a breakdown mill equipped with upper and lower rolls, a universal mill with upper and lower horizontal rolls and a vertical roll, and an edger mill with upper and lower horizontal rolls with variable body width, and a roll axis. A widening/slanting forming process and variable body width in which a pair of upper and lower oblique rolls whose cores are at a predetermined angle α with respect to a plane perpendicular to the horizontal plane in the rolling direction are provided so that the width can be adjusted in the direction perpendicular to the rolling direction. 1. A row of rolling equipment for straight steel sheet piles, characterized by sequentially arranging finishing rolling processes equipped with upper and lower horizontal rolls. 5. The line of rolling equipment for linear steel sheet piles according to claim 4, further comprising vertical rolls rotatably provided with flanges projecting on the circumference of the trunk on either side or one of the upper and lower horizontal rolls in the finish rolling process.