WO2010139200A1

WO2010139200A1 - Rolling method for shell ring and device thereof

Info

Publication number: WO2010139200A1
Application number: PCT/CN2010/070301
Authority: WO
Inventors: 吴生富; 周晓平; 刘刚; 马克; 王光儒; 付环宇
Original assignee: 中国第一重型机械股份公司; 一重集团大连设计研究院有限公司
Priority date: 2009-06-05
Filing date: 2010-01-21
Publication date: 2010-12-09
Also published as: CN101574703B; CN101574703A

Abstract

A rolling method for a shell ring includes a first roller (31) and a second roller (32) which extrude the inner wall and the outer wall of the shell ring respectively. The first roller (31) and the second roller (32) are driven by a driving unit (6) during a rolling process. A rolling device for the shell ring includes a first roller (31) and a second roller (32) which extrude the inner wall and the outer wall of the shell ring respectively. The first roller (31) and the second roller (32) are driving rollers driven by the driving unit (6). The method overcomes the default of the surface anti-fatigue stress generated on the inner wall of the shell ring, so as to improve mechanical performance of shell ring finished products.

Description

Tube rolling process and rolling equipment thereof

This application claims priority to Chinese Patent Application No. 200910145738.6, entitled "One Tube Rolling Process and Rolling Equipment" by the Chinese Patent Office on June 5, 2009, the entire contents of which are hereby incorporated by reference. Combined in this application.

Technical field

The invention relates to the field of metal rolling technology, in particular to a barrel rolling process. The invention also relates to a rolling apparatus that can process a barrel section using the above process.

Background technique

With the rapid development of China's economic construction, various sizes of cylinder sections are increasingly used in various fields of industrial production. The increase in demand has led to improvements in the processing of the barrel section and the improvement of the processing equipment used in conjunction with the process.

Many production units use a rolling mill to process the barrel sections. The rolling mill generally comprises a driving motor, an outer working roller, an inner working roller and the like, and the processed cylinder section is set on the outer circumference of the working roller, and the pressing and stretching action of the inner cylinder and the outer working roller on the cylinder section is realized. Rolling processing. At present, the single-drive method is used to process the barrel section, that is, the outer work roll is the active roll, the inner work roll is the passive roll, and the drive motor provides power for the outer work roll, and the outer work roll is driven to rotate at a certain speed. Due to the friction between the outer work roll and the barrel section being machined, the machined barrel section rotates with the rotation of the outer work roll, and at the same time, due to the friction between the machined barrel section and the inner work roll, the inner working is driven. The roller rotates.

There are unavoidable defects in machining the barrel section in the form of a single drive. Firstly, the rolling torque in the form of a single drive is small, which results in a small rolling force applied to the barrel section being processed, and the compression amount of the barrel section during the rolling process is relatively small; when processing the barrel section having a small wall thickness Because the wall thickness has little effect on the stress transmission, the single drive will not have a great influence on the quality of the finished product. When machining the thick section of the cylinder, the transmission of the tensile stress is affected by the wall thickness. The inner and outer surfaces of the barrel section are torn, and the single-drive cannot process the large-sized cylinder section, which limits the scale of the processed cylinder section. Secondly, during the rolling process, the deformation of the inner wall of the processed cylinder section (ie, the contact surface with the passive inner working roller) is tensile deformation. When the stress approaches the strength limit, defects are easily generated, resulting in processing. The mechanical properties of the barrel section are poor, which affects the quality of the finished product. In addition, in the single-drive mode, the torque difference between the two work rolls on the rolling mill is large, and the tilting moment is generated on the rolling mill, which makes the rolling mill unstable. It can be seen that the product quality and product scale of the tube sections obtained by the existing processing methods are not ideal. In summary, how to improve the rolling force of the roll to the barrel section and overcome the stress defects generated by the inner wall of the barrel section to improve the product scale and product quality of the barrel section has become a problem to be solved by those skilled in the art.

Summary of the invention

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for increasing the rolling force of a roll against a barrel section and overcoming the stress defects generated by the inner wall of the barrel section to improve the product size and product quality of the barrel section. Another object of the present invention is to provide a barrel rolling apparatus which can use the above method.

In order to solve the above technical problems, the present invention provides a barrel rolling apparatus including a first roll and a second roll, which respectively press the inner wall and the outer wall of the barrel section, the first roll and the second The rolls are driven rolls driven by a drive unit.

Preferably, the output torque of the driving device is adjustable; during rolling, the ratio of the actual output torque of the first roller to its maximum output torque is equal to the actual output torque of the second roller and its maximum output torque ratio.

The present invention also provides a barrel rolling method for respectively pressing an inner wall and an outer wall of the barrel section by a first roll and a second roll, wherein the first roll and the second roll are both in a rolling process Rotate under the drive of the drive unit.

Preferably, during rolling, the ratio of the actual output torque of the first roll to its maximum output torque is equal to the ratio of the actual output torque of the second roll to its maximum output torque.

Preferably, the rolling process comprises the following stages in sequence:

1) Flattening and rolling stage: In this stage, the rolling section is controlled by pressure, and the barrel section is rolled to at least one week and then transferred to the next stage;

2) Large-pressure rolling stage: This stage adopts a pressure-controlled rolling method, and the rolling force is greater than the rolling force of the flattening rolling stage; when the wall thickness of the barrel section reaches a predetermined thickness, a lower stage; the predetermined thickness is greater than a target thickness of the barrel section;

3) step-down rolling stage: this stage adopts pressure-controlled rolling method, and the rolling force is smaller than the rolling force of large-pressure rolling; when the wall thickness of the cylinder section reaches the target thickness, it is transferred Next stage

4) Constant roll seam rolling stage: This stage uses a position-controlled rolling method, in which the barrel is rolled for at least one week.

Preferably, the rolling force of the flattening rolling stage is determined by the following model: K _l d ₂ [d _x ² + d _x d ₂ - K _x d.

Pi two ^b i -σ.

K ₂ (d _x +d ₂ ) where: pi : rolling pressure in the flattening rolling stage, the unit is kN;

Bl : the width of the barrel blank, the unit is mm;

K1 : parameter, which ranges from 4mm to 6mm;

D2: the outer diameter of the barrel blank, the unit of which is mm;

Dx: the diameter of the first roll, the unit is mm;

σ . The immediate yield limit of the barrel blank, the unit is MPa;

K2: Parameter, which has a value range of 900 1100.

Preferably, the value of the parameter is: Kl=5mm, K2=1000.

Preferably, the rolling force of the large pressure rolling stage is determined by the following model: where: ^p p ₂ : rolling pressure of the large pressure rolling stage, the unit of which is kN;

K3 parameter, the value range is 0.001 0.002;

K4 parameter, its value range is 19451 19452;

K5 parameter, its value range is 187~188;

The thickness of the barrel blank, the unit is mm;

K6 parameter, which has a value range of 12 13;

The temperature in the large pressure rolling stage is expressed in units. C ;

K7: parameter, which ranges from 0.1 to 0.2;

b The width of the barrel blank, the unit is mm.

Preferably, the predetermined thickness is a wall of the tubular section when the target thickness is 8 mm to 12 mm, and when the cylinder section is offset from the center position, the rolling force on the offset side is increased; The side of the barrel section is close.

Preferably, the rolling force of the step-down rolling stage is determined by the following model: Where: : rolling pressure in the step-down rolling stage;

¹ 2 in the step-down rolling stage, the straight line distance of the outer circle of the cylinder section;

! The outer circumference of the barrel section when the thickness of the barrel section is close to the target value;

^4: Rolling force of the rolling equipment at the thickness of the finished section; its size is determined by the following mode:

P ₄ = K ₃ (K ₄ + K ₅ t _{2 -} K ₆ T _{w -} K ₇ t ₂ T b ₂ where: t2: wall thickness at the end of the tube section, the unit is mm;

B2: The width of the finished product, in mm.

The technical solution of the barrel rolling provided by the present invention is that the two rolls are driven by a driving device. The double-drive method in which the two rolls are both active rolls increases the rolling moment during the rolling process, thereby increasing the rolling force applied by the rolls to the processed barrel section, and the processing wall thickness is large. In the case of the tube section, the large rolling force overcomes the influence of the wall thickness on the stress transmission, and the stress on the inner and outer sides of the barrel section is uniform, and the surface tear is not generated, making it possible to process the larger size of the barrel section and enlarge The size range of the processed barrel section increases the product scale of the barrel section processing. At the same time, the double-roller transmission causes the deformation of the inner wall and the outer wall of the processed cylinder section to be crushed and deformed, and the tensile defects are not easily generated, so that the mechanical performance of the processed cylinder section is better, and the product quality of the cylinder section is improved. In addition, when the two-roller transmission is working, the torque generated by the two rolls can be basically balanced, and the tilting torque is hardly generated on the rolling equipment, which avoids the tendency of the rolling equipment to tip over and improves the stability of the rolling equipment. .

In a technical solution provided by a specific embodiment, the ratio of the actual output torque of the first roll to its maximum output torque is equal to the ratio of the actual output torque of the second roll to its maximum output torque, and the torque of each actual output and each roll The maximum output torque is matched in the same proportion. When the maximum output torque of one of the rolls is small, the actual output torque matched to it is small, and the maximum output torque of the other roll is large, and the actual output torque matched with it is also large. When rolling the cylinder section, the two rolls reach their respective maximum output torques at the same time, which improves the overall performance of the technical solution, increases the rolling force range of the rolls, and makes it possible to expand the size range of the processed barrel sections.

In another embodiment, the method for rolling a barrel section provided by the present invention may include a flattening rolling stage, a large pressure rolling stage, a pressure reducing rolling stage, and a constant roll seam rolling stage. The rolling pressures of the above four stages are different. During the rolling process, different rolling stages are selected according to the change of objective factors such as the wall thickness of the barrel section to determine the suitable rolling force and the barrel section is improved. Processing Accuracy and productivity.

The rolling pressure in each processing stage of the above-mentioned barrel section can be obtained by the respective rolling pressure calculation model, which determines the corresponding relationship between the rolling pressure and the size of each stage, and substitutes the parameters related to the processed barrel section. The formula of each stage can be used to obtain the rolling pressure of each stage. No matter what size of the barrel blank can be obtained, the tailored rolling scheme can be obtained by formula calculation, and the rolling method of the barrel section can be improved. Adaptability.

DRAWINGS

1 is a schematic structural view of a barrel processing apparatus according to an embodiment of the present invention; and FIG. 2 is a schematic flow chart of a barrel processing method according to an embodiment of the present invention.

detailed description

The core of the present invention is to provide a method of rolling a barrel section, which improves the rolling force of the roll to the barrel section and overcomes the stress defect of the inner wall of the barrel section, thereby improving the product scale and product quality of the barrel section. Another core of the present invention is to provide a rolling apparatus for processing a barrel section using the above method.

The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

1 and FIG. 2, FIG. 1 is a schematic structural view of a barrel processing apparatus according to an embodiment of the present invention; FIG. 2 is a schematic flow chart of a processing method of a barrel section according to an embodiment of the present invention.

In a specific embodiment, the tubular rolling technical solution provided by the present invention comprises two frames

1 , the frame 1 can be a closed frame, the two frames 1 are fixed by a beam 2, and the beam 2 can include a lower beam 22 and a middle beam 21 to ensure the stability of the connection of the frame 1 and the whole machine. stable. Two hydraulic cylinders 4 are provided on the lower surface of the frame of the frame 1 for supplying rolling pressure to the work rolls during rolling and controlling the roll gaps in a timely manner. A first roll 31 is disposed at an upper portion of the hydraulic cylinder 4, and a second roll 32 is disposed at a lower portion of the upper surface of the window of the frame 1. The rolling section apparatus provided by the present invention further includes a roll changer 5 for At the beginning and end of the rolling, the second roll 32 is taken. The first roll 31 and the second roll 32 are both active rolls, and both of the work rolls are driven by the drive unit 6. In operation, the processed barrel blank is placed on the upper surface of the first roll 31, and the roll change cart 5 pushes the second roll 32 so that the outer circumference of the second roll 32 comes into contact with the inner ring of the machined barrel section. Both the first roll 31 and the second roll 32 are rotated about the respective axes by the driving device 6, and the processed barrel is located between the first roll 31 and the second roll 32, and the inner wall of the barrel and the second roll 32 Contacted, and the outer wall thereof is in contact with the first roll 31, and is passed through the first roll 31 to the outside of the barrel The extrusion of the wall and the pressing action of the second roll 32 on the inner wall of the barrel section roll the barrel section. According to the tubular rolling technology of the present invention, the first roller 31 and the second roller 32 are double-drive modes of the driving roller, which increases the rolling moment during the rolling process, thereby increasing the roller application. The rolling force for the barrel section to be processed; when processing the barrel section with a small size, the first roller and the second roller provide a uniform torque to the barrel section, so that the processing quality of the barrel section is higher; In the case of the cylinder section, the rolling moment on both sides overcomes the influence of the wall thickness on the stress transmission, eliminating the tendency of the inner and outer surfaces of the processed cylinder section to tear, making it possible to use the rolling mill to process the larger size of the cylinder section, expanding the The size range of the processing barrel section increases the product size of the barrel section. At the same time, during the rolling process of the double-drive method, the deformations caused by the first roll and the second roll on the inner wall and the outer wall of the processed barrel section are both extrusion deformation, and it is not easy to exceed the tensile limit, and the mechanical properties of the product are better and improved. The product quality of the tube section. In addition, when the two-roller transmission is in operation, the torque generated by the first roll and the second roll can be basically balanced, and the tilting torque is hardly generated on the rolling equipment, thereby avoiding the tendency of the rolling equipment to tip over and improving the rolling equipment. Stability.

In the above embodiment, the drive unit 6 may be a motor. The power of the first roll 31 and the second roll 32 are both supplied by the motor 6, and through the reducer 7, the conversion between the output power and the required power of the roll is realized. Finally, the speed reducer 7 is realized by the universal joint shaft 8 Power transmission between the first roll 31 and the second roll 32. The motor provides continuous and stable power to the rolls, enabling stable, continuous operation of the barrel rolling equipment.

Of course, the driving device is not limited to the motor, and may be other power devices capable of providing stable output power, for example, various types of internal combustion engines or hydraulic pumps.

In a specific embodiment, the barrel rolling technique feature provided by the present invention may also have a mechanism for adjusting the output torque of the rolls. During the rolling process, the ratio of the actual output torque of the first roll 31 to its maximum output torque can be guaranteed to be equal to the ratio of the actual output torque of the second roll 32 to its maximum output torque. When the maximum output torque of the first roll 31 is small, the actual output torque matched thereto is also small, and the maximum output torque of the second roll 32 is large, and the actual output torque matched thereto is also large. During the manufacturing process, the first roll 31 and the second roll 32 reach their respective maximum output torques at substantially the same time, which improves the overall performance of the rolling method, increases the rolling force range of the rolls, and enlarges the processed barrel section. A range of sizes is possible.

In another embodiment, first, the bucket blank is hung on the upper surface of the first roll 31; then, the roll changer 5 pushes the second roll 32 to the rolling equipment to set the second roll 32 to the barrel. Within the festival At the time, one end of the second roll 32 is inserted into the coupling, and then enters the rolling stage. The above process can also be replaced in other conventional ways.

The rolling process in turn includes the following stages:

Flattening rolling stage S1 :

At this stage, the pressure-controlled rolling method is used to eliminate the convex and concave portions on the barrel blank to prepare for the following rolling process. After one week of rolling, if the degree of unevenness of the barrel section still cannot meet the requirements of large-pressure rolling, the flattening rolling can be continued; the surface unevenness of the barrel section is basically eliminated, and when the requirements for large-pressure rolling are reached, the next stage is transferred.

Large pressure rolling stage S2:

At this stage, a pressure-controlled rolling method is employed, and the rolling force is greater than the rolling force of the smoothing rolling stage S1. During the rolling process, the wall thickness of the machined barrel section is monitored, and when the wall thickness of the barrel section reaches a predetermined thickness, it is transferred to the next stage.

During the rolling process, the wall thickness of the machined section is monitored to select the most suitable processing mode for different wall thicknesses. The method of monitoring the wall thickness can realize real-time monitoring through the automatic control device, and control the processing stage through the feedback pressure signal, obtain more accurate detection value through modern control means, and change the rolling pressure in real time through the feedback of the detection signal. The rolling pressure is adapted to the real-time variation of the wall thickness. It is also possible to manually detect the wall thickness of the barrel section at a certain time, and manually select the processing stage by the detected wall thickness value. Although the detection accuracy is reduced, the rolling quality is not caused. Great impact, and the method is simple and low cost.

The predetermined thickness is greater than a target thickness of the barrel section, and the predetermined thickness may be a distance from the target thickness

Wall thickness of the barrel section from 8mm to 12mm.

Step-down rolling stage S3:

At this stage, a pressure-controlled rolling method is employed, and the rolling force is smaller than the rolling force of the large-pressure rolling stage S2. During the rolling process, the wall thickness of the machined section is monitored, and when the wall thickness of the barrel section reaches the target thickness, it is transferred to the next stage.

The manner of monitoring the wall thickness may also be an automatic control mode or a manual control mode. The specific implementation manner is the same as the above, and details are not described herein again.

The determination of the target thickness generally requires factors such as the size of the integrated billet, the size of the finished product, and the widening of the rolling process. The present invention controls the wall thickness of the barrel as a target value, and the thickness thereof is Target thickness. It is also possible to measure the outer diameter of the barrel section as a target value and feed it back. Constant roll seam rolling stage S4:

The constant roll seam rolling stage S4 uses a position-controlled rolling method, and in this stage, the barrel section is rolled at least one week, and the rolling is generally completed after two weeks of rolling.

During the rolling process, the rolling pressures of the above stages are different. During the rolling process, according to the wall thickness of the cylinder section, different rolling stages are selected to determine the most suitable processing method. The processing precision and production efficiency of the barrel section.

After the end of the rolling, the second roll 32 stops rotating, and the roll change cart 5 pulls the second roll 32 out of the apparatus, and the crane lifts the finished product of the barrel to complete the rolling. The above processes and apparatus can also be replaced in other conventional ways.

During the rolling process, the processed cylinder section may deviate from the center position, and after detecting the offset of the cylinder section, the detecting component transmits a signal to the control component, and the control component converts the obtained position signal into an action signal and transmits it to the actuator. The actuator can reduce the tendency of the machined cylinder to slide to one side by increasing the rolling force on the offset side, so that the cylinder section returns to the normal working state. The offset side is the side on which the barrel section slides. Through the real-time adjustment of the position of the barrel section, the processed barrel section is kept in the centered position during the work, and the rolling precision is improved. Of course, the adjustment of the above position can also be manually adjusted, and although the adjustment cannot be performed in real time, the working state of the barrel section can be controlled.

The rolling pressure of the flattening rolling stage S 1 can be determined by the following model:

Where: pi : rolling pressure during the flattening rolling stage, the unit is kN;

Bl : the width of the barrel blank, the unit is mm;

K1 : parameter, which ranges from 4mm to 6mm;

D2: the outer diameter of the barrel blank, the unit of which is mm;

Dx: the diameter of the first roll, the unit is mm;

σ . The immediate yield limit of the barrel blank, the unit is MPa;

K2: Parameter, which ranges from 900 to 1100.

For the processed barrel sections of different sizes, it is only necessary to substitute the value of the width of the barrel blank and the diameter of its outer circle into the above formula, that is, the rolling pressure which is most suitable for the rolling stage of the barrel section can be obtained. The force is applied to the rolling of the cylinder sections of various specifications to improve the applicability of the method.

In the above model for determining the rolling pressure pi in the flattening rolling stage, the value of the parameter may be Kl=5 mm, K2=1000, which is a preferred value of the parameter in the above formula, and a more suitable rolling pressure can be obtained. size.

In the above formula, the value of the Kuyueliang limit can be the immediate flexing limit in the rolling process, that is, the yield limit of the material in different states of the barrel, and the yield limit of the barrel in the initial state of the stage can be regarded as immediate yielding. At the limit, the obtained rolling pressure is constant, although the accuracy is reduced, it has little effect on the entire rolling process, and the calculation amount is greatly reduced.

The rolling force of S2 in the large pressure rolling stage can be determined by the following model:

P ₂ = K ₃ (K ₄ + K ₅ t, -K ₆ T _w -K^T b, where: · · rolling pressure in the large pressure rolling stage, the unit is kN;

K3: parameter, which ranges from 0.001 to 0.002;

K4: parameter, its value range is 19451~19452;

K5: parameter, which ranges from 187 to 188;

The thickness of the barrel blank, the unit is mm;

K6: parameter, which ranges from 12 to 13;

τ The instantaneous temperature of the large pressure rolling stage, the unit is. c;

K7: parameter, which ranges from 0.1 to 0.2;

b The width of the barrel blank, the unit is mm.

For different sizes of processed barrel sections, it is only necessary to substitute the wall thickness and width of the barrel blank and the measured temperature value during rolling into the above formula, that is, the rolling of the barrel section during the large pressure rolling stage can be obtained. The pressure makes the barrel rolling method suitable for rolling of various sizes of barrel sections, which improves the applicability of the method.

In the above formula, the value of temperature ⁷ ^ can be the instantaneous temperature during the rolling process, and the rolling temperature obtained by bringing the detected instantaneous temperature value into the formula is more accurate; the initial temperature of the stage can also be regarded as the instantaneous temperature. The obtained rolling pressure is constant, although the accuracy is reduced, it has little effect on the whole rolling process, and the calculation amount is greatly reduced.

In the above model for determining the rolling force A of the S2 during the large pressure rolling stage, the value of the parameter may be K3=0.0015, K4=19451.96, Κ5=187.6, Κ6=12.6, Κ7=0.14. The above values are preferred values of various parameters obtained by experiments, and a more suitable rolling pressure can be obtained.

The rolling pressure of S3 in the step-down rolling stage can be determined by the following model:

P _ P (A _ ! ₂

Where: ^ρ . rolling pressure in the step-down rolling stage;

¹ 2: In the step-down rolling stage, the line distance of the outer circle of the barrel section;

^4: Rolling force of the rolling equipment at the thickness of the finished section; its size can be determined by the following mode:

B2: The width of the finished product, in mm.

The values of the parameters in this stage refer to the large pressure rolling stage S2, which will not be described here.

The rolling pressure in each stage of the above-mentioned barrel processing is determined by the respective rolling pressure calculation model, which makes the value and control of the rolling pressure more precise, and further improves the barrel processing in the processing method of the barrel. Accuracy, at the same time, regardless of the size of the barrel blank, the tailored rolling scheme can be obtained by formula calculation, which improves the applicability of the rolling method.

The barrel rolling method provided by the present invention may further include a rounding process or the like to further improve the machining accuracy of the barrel section.

The above detailed description of the barrel rolling apparatus and the method of barrel rolling provided by the present invention is only for aiding in understanding the method of the present invention and its core idea. It should be noted that those skilled in the art can also make several improvements and modifications to the present invention without departing from the principles of the present invention, for example, different values of various parameters within a specified range, and the like. And modifications are also intended to fall within the scope of the appended claims.

Claims

OP090852 WO 2010/139200 PCT/CN2010/070301 - 11 - Claims

What is claimed is: 1. A barrel rolling apparatus comprising a first roll and a second roll, the two respectively pressing an inner wall and an outer wall of the barrel section, wherein the first roll and the second roll are both The drive roller driven by the drive unit.

2. The barrel rolling apparatus according to claim 1, wherein an output torque of said driving device is adjustable; a ratio of an actual output torque of said first roller to a maximum output torque thereof during rolling Is equal to the ratio of the actual output torque of the second roll to its maximum output torque.

3. A method of rolling a barrel section, wherein the inner wall and the outer wall of the barrel section are respectively pressed by a first roll and a second roll, characterized in that, during the rolling, the first roll and the second roll The rolls are all rotated by the drive unit.

4. The method of rolling a barrel section according to claim 3, wherein a ratio of an actual output torque of the first roll to a maximum output torque thereof is equal to an actual output of the second roll during rolling The ratio of torque to its maximum output torque.

The method of rolling a tubular section according to claim 4, wherein the rolling process comprises the following stages in order:

6. The method of rolling a barrel section according to claim 5, wherein the rolling force in the flattening rolling stage is determined by the following model:

OP090852

WO 2010/139200 PCT/CN2010/070301

- 12- where: p _{1 :} the rolling pressure in the flattening rolling stage, the unit is kN;

Bi : the width of the barrel blank, the unit is mm;

Ki: parameter, which ranges from 4mm to 6mm;

d ₂ : the outer diameter of the barrel blank, the unit of which is mm;

d _x : diameter of the first roll, the unit of which is mm;

a _s : immediate yield limit of the tube blank, the unit is MPa;

K ₂ : Parameter, which ranges from 900 to 1100.

7. The method of rolling a tubular section according to claim 6, wherein the value of the parameter is: corpse 5 mm, K ₂ = 1000.

8. The method of rolling a barrel section according to claim 5, wherein the rolling force in the large pressure rolling stage is determined by the following model:

P ₂ = K ₃ (K ₄ + K ₅ t, -K ₆ T _w -K^T b,

Where: P ₂ : rolling pressure in the large pressure rolling stage, the unit is kN;

K ₃ : parameter, which ranges from 0.001 to 0.002;

Κ 4 : parameter, its value range is 19451~19452;

Κ ₅ : parameters, which range from 187 to 188;

t _{1 :} wall thickness of the tube section blank, the unit of which is mm;

K ₆ : parameter, which ranges from 12 to 13;

T _W : The instantaneous temperature during the large pressure rolling stage, in units. c;

K ₇ : parameter, which ranges from 0.1 to 0.2;

b _x The width of the blank section, the unit is mm.

The method of rolling a tubular section according to claim 8, wherein a difference in thickness between the predetermined thickness and the target thickness is in the range of 8 mm to 12 mm.

10. The method of rolling a tubular section according to claim 8, wherein during the rolling, when the cylinder section is offset from the center position, the rolling force on the offset side is increased; The side of the barrel section that is adjacent.

11. The method of rolling a barrel section according to claim 8, wherein the rolling force of the step-down rolling section is determined by the following model: 852

O 2010/139200 PCT/CN2010/070301

-13-

(p, _ p '

P = P, where: P ₃ : rolling pressure in the step-down rolling stage;

/ ₂ : the line distance through which the outer circumference of the barrel section is rotated during the step-down rolling stage;

: the outer circumference of the barrel section when the thickness of the barrel section is close to the target value;

P ₄ : rolling force of the rolling equipment under the thickness of the finished section; its size is determined by the following model: P ₄ = K ₃ (K ₄ + K ₅ t _{2 -} K ₆ T _{w -} K ₇ t ₂ T _w ) b ₂

Where: t ₂ : the wall thickness of the finished product, the unit is mm;

b ₂ : The width of the finished product, the unit is mm.