Progressive pipe flattening forming method and device based on six-axis roller bed

Abstract

The invention discloses a gradual pipe flattening forming device based on a six-axis roller machine. The gradual pipe flattening forming device comprises a roller set and a guide wheel set. The roller group is used for driving to-be-formed pipes to be fed and formed, and the guide wheel group is used for guiding the pipes to avoid torsion; the invention further discloses a gradual pipe flattening forming method based on the six-axis roller machine, the rollers and the guide wheels are designed and manufactured firstly, then the rollers and the guide wheels are installed and debugged, and finally the pipe to be formed is subjected to multi-pass gradual rolling flattening forming. By means of the combined design of the existing six-shaft roller machine and the progressive groove roller set, efficient and accurate forming of the stainless steel pipe is achieved, and the stainless steel pipe forming machine has the advantages of being low in design and manufacturing cost, high in product percent of pass, high in production efficiency and wide in adaptation range.

Description

Technical Field

[0001] This invention belongs to the field of metal tube processing and relates to a method and apparatus for progressive flattening of tubes based on a six-axis rolling bed. Background Technology

[0002] Pipe flattening refers to the process of flattening and deforming a circular cross-section pipe to achieve a target cross-section that meets usage requirements. The principle of pipe flattening is to use mechanical force to compress the pipe radially, causing its cross-sectional shape to transition towards the target cross-section, thereby achieving the flattening purpose.

[0003] In existing pipe flattening technology, Chinese patent application CN118635380A, entitled "A Guiding Mechanism and a Pipe Flattening Device with the Guiding Mechanism," primarily innovates by adding a guiding mechanism. This mechanism comprises a mounting box, movable ladder blocks, a guiding component, and a clamping component. The guiding mechanism guides the pipe smoothly into the flattening area along a predetermined path, ensuring the pipe is in the correct position during flattening. This application's guiding mechanism clamps the pipe, ensuring its stability before entering the flattening mechanism and preventing vibration or displacement from affecting the flattening effect. While this invention solves the pipe fixing problem, it shares the same risk of cracking as existing pipe flattening methods. Furthermore, this method requires a redesigned power source, making the device more complex and costly.

[0004] Furthermore, no solutions based on six-axis rolling mill equipment have been found in the existing technology. Therefore, there is an urgent need to develop a tube progressive flattening forming method and forming device based on a six-axis rolling mill. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a tube progressive flattening forming method and forming device based on a six-axis rolling bed. This eliminates the need to redesign the power source, reduces the production cost of the forming device, and the progressive deformation of the cross section reduces the risk of wrinkles and cracks during the tube flattening process, thereby improving the uniformity and consistency of the flattening deformation.

[0006] To achieve the above objectives, the present invention employs the following technical solutions: A tube progressive flattening forming device based on a six-axis rolling bed includes a roller assembly and a guide roller assembly; The roller assembly includes two rollers (1), which are arranged vertically opposite each other. The roller assembly is used to drive the tube to be formed to feed and form. The guide wheel assembly is set into two sets, which are symmetrically arranged on both sides of the roller assembly. Each set of guide wheel assemblies includes two guide wheels (2), which are arranged vertically opposite each other. The guide wheel assembly is used to guide the tube to avoid twisting and reduce the defect rate. The interface structure of the rollers (1) and guide wheels (2) is compatible with the equipment interface of the six-axis roller bed, so as to realize detachable installation. Each roller (1) of the roller group and each guide roller (2) of the guide roller group have several identical grooves distributed along the axial direction on their outer periphery. The number of grooves and the structural dimensions are determined based on the deformation of the original circular tube to the target cross-section tube, and there is at least one groove.

[0007] As a preferred embodiment, the roller (1) is made of metal, and the guide wheel (2) is made of non-metallic nylon material.

[0008] As a preferred embodiment, the relative vertical positions of the two rollers (1) of the roller group and the two guide rollers (2) of each guide roller group are adjustable to accommodate different specifications of pipes to be formed.

[0009] A forming method for tube progressive flattening forming apparatus based on a six-axis rolling mill, characterized by comprising the following steps: S1: Design and manufacturing of roller (1) and guide wheel (2) Based on the original circular cross-sectional dimensions, target cross-sectional dimensions, and material properties of the pipe to be formed, the total deformation is calculated. Under the premise that the single-pass deformation of adjacent grooves does not exceed the deformation limit of the pipe material and is not less than the minimum effective deformation, the cross-sectional dimensions and number of grooves of roller (1) and guide roller (2) are designed, and roller (1) and guide roller (2) are manufactured according to the design. It is also ensured that the interface of roller (1) and guide roller (2) matches the equipment interface of the six-axis roller bed. S2: Installation and debugging of roller (1) and guide wheel (2) Install the roller (1) and guide roller (2) at the corresponding positions on the six-axis roller machine through the interface; adjust the upper and lower clearances of each roller group and guide roller group respectively, and apply lubricating oil; S3: Multi-pass progressive rolling flattening forming In descending order, the pipes to be formed are inserted into the corresponding transition grooves of the rollers (1) through the transition grooves of the guide rollers (2). The rotating roller assembly drives the pipes to feed and squeezes the pipes to cause slight deformation, thus obtaining intermediate pipes. The intermediate pipe obtained in the previous pass is inserted into the end groove of the roller (1) through the end groove of the guide wheel (2). The rotating roller group drives the pipe to feed and squeezes the pipe to cause slight deformation until the target pipe is obtained.

[0010] As a preferred method, after processing is completed, the target pipe obtained in step S3 is inspected using vernier calipers or other testing equipment to check whether the forming quality of the target pipe meets the design requirements, including checking the cross-sectional dimensions of the target pipe and the surface quality (cracks, wrinkles).

[0011] As a preferred method, in step S3, the direction in which the pipe is inserted into the groove is in the same direction as the tangential direction of the rotation direction of the roller (1) to avoid slippage when the pipe is fed.

[0012] As a preferred method, in step S3, the total number of passes is consistent with the number of grooves in one of the rollers (1) / guide rollers (2), and is specifically determined according to the material properties of the tube to be formed and the total deformation.

[0013] This invention achieves efficient and precise forming of stainless steel pipes through a combination design of "existing six-axis roller bed + progressive groove roller assembly and guide wheel assembly". The specific beneficial effects are as follows: I. Significantly reduced equipment costs: Based on the existing six-axis roller machine, there is no need to redesign and manufacture the power source. Only the rollers (1) and guide rollers (2) need to be developed, saving the power source R&D costs (reducing the total equipment investment by 60% to 70%). At the same time, the guide roller assembly is made of nylon material, which further reduces the manufacturing cost by 40% to 60% compared with the all-metal roller assembly. II. Improve product qualification rate and consistency: The six-axis roller machine provides a stable speed to ensure constant rotation of the roller assembly. Combined with the progressively sized grooves, it makes the stainless steel pipe deform evenly, thereby improving the product qualification rate. 3. Improved production efficiency: The forming process requires no manual intervention or adjustment, and the operation is convenient and simple, which improves the production efficiency of rolling flattening of pipes; IV. Wide range of applications: By adjusting the size of the grooves of the roller (1) and the guide roller (2), different specifications of round pipes can be formed into different oblong cross sections. There is no need to replace the main body of the six-axis roller bed. Only the roller group needs to be switched to meet the production needs of multiple varieties. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of a tube progressive flattening forming device based on a six-axis rolling bed.

[0015] Figure 2 This is a three-view diagram of a progressive flattening roller assembly for producing pipes of a certain specification, based on a six-axis roller bed.

[0016] Figure 3This is a comparison diagram of the cross-sections of a certain specification of pipe before and after forming.

[0017] Figure 4 This is a schematic diagram showing the direction of tube insertion into the groove and the rotation direction of the rollers in a tube progressive flattening forming device based on a six-axis roller bed.

[0018] In the diagram: 1-roller, 2-guide wheel, 3-groove one, 4-groove two, 5-groove three, 6-groove four, 7-roller interface. Detailed Implementation

[0019] The present invention will now be described in detail with reference to the accompanying drawings.

[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0021] Example: like Figures 1-4 As shown, Example: A stainless steel pipe of a certain specification is formed with a thickness δ=1mm, an original inner diameter of Φd2=13mm, and a target pipe cross-section of an oblong shape with dimensions Ra=3.5mm and L=10mm.

[0022] Equipment preparation: Based on the existing interface dimensions of the six-axis roller machine, the dimensions of roller interface (7)7 are determined to be L6 = 7.5mm, L5 = mm, L6=7.5mm, L7= mm, Φd1=Φ mm, the guide wheel (2) interface is a Φ60mm shaft hole connection, and the speed range is 3-20r / min; Roller assembly and guide wheel assembly: The dimensions of grooves one to four are as follows: Transition groove; Groove 1 (3); Ra1=6.5mm, L1=1.5mm; Groove 2 (4); Ra2=5.5mm, L2=3mm; Groove 3 (5); Ra3=5mm, L3=4mm; End groove; Groove four (6); Ra4=3.5mm, L4=5mm; Forming process: Installation and debugging: The initial gap of roller (1) is set to 0.5~0.9mm, and lubricating oil is applied; Several transition passes (one to three): Set the speed of the six-axis roller bed and start it, and pass through groove one (3), groove two (4), and groove three (5) in sequence to obtain intermediate tubes; Final pass, fourth pass: Adjust the gap of roller (1) to 0.2-0.4mm, and obtain the target pipe material through groove 46; The quality inspection results of the target pipes obtained from the sampling inspection are as follows: Surface quality: No cracks or wrinkles, meets design requirements.

[0023] This invention is not limited to the specific embodiments described above. The invention extends to any new feature or combination disclosed in this specification, as well as any new method or process step or combination disclosed herein.

Claims

1. A six-axis roll-beds based tube incremental bulge forming apparatus, characterized by; It comprises a roller set and a guide wheel set; The roller set comprises two rollers (1) arranged oppositely in up and down directions, and is used to drive the pipe to be shaped to feed and shape; the guide wheel set is arranged in two groups, and two groups of the guide wheel set are symmetrically arranged on both sides of the roller set; each group of the guide wheel set comprises two guide wheels (2) arranged oppositely in up and down directions, and the guide wheel set is used to guide the pipe to avoid twisting; and the interface structures of the rollers (1) and the guide wheels (2) are adapted to the equipment interface of the six-axis roller bed. The rollers (1) and the guide wheels (2) are provided with grooves on the outer periphery, and the number and structure size of the grooves are determined according to the deformation amount of the original circular pipe to the target cross-section pipe.

2. The apparatus for incremental tube flattening based on six-axis roll bed according to claim 1, characterized in that; The manufacturing material of the rollers (1) is metal, and the manufacturing material of the guide wheels (2) is non-metal nylon material.

3. The apparatus for incremental tube flattening based on six-axis roll bed according to claim 1, characterized in that; The up and down relative positions of the two rollers (1) of the roller set and the two guide wheels (2) of each group of the guide wheel set can be adjusted to adapt to different specifications of the pipe to be shaped.

4. A method of forming a tube by the apparatus according to any one of claims 1 to 3, wherein The method comprises the following steps: S1: according to the original circular cross-section size of the pipe to be shaped, the target cross-section size and the material characteristics, the total deformation amount is calculated, and the cross-section size and the number of the grooves are determined; S2: the roller set and the guide wheel set are installed in the corresponding positions of the six-axis roller bed through the interface, the up and down clearances of the roller set and the guide wheel set are adjusted respectively, and lubricating oil is applied; S3: the six-axis roller bed is started, the pipe to be shaped is inserted into the groove of the roller (1), the pipe is fed forward with the rotation of the roller, and the pipe is deformed by being extruded; the pipe obtained in the previous pass is inserted into the groove of the roller (1) in the next pass, the pipe is fed forward with the rotation of the roller, and the target pipe is obtained.

5. A method of incremental tube flattening based on a six-axis roll bed according to claim 4, wherein; After the processing is completed, the target pipe obtained in the step S3 is detected to check whether the forming quality meets the design requirements.

6. A method of tube incremental bulge forming based on six-axis roll bed according to claim 5, characterized in that; In the step S3, the direction of inserting the pipe into the groove is the same as the tangential direction of the rotation of the roller (1).

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