Research and development of the hottest flexible r

Research and development of flexible roll forming machine

Abstract: about 90 years ago, Japan's roll forming technology was limited to the production of welded tubes, bicycle rims and roller shutter door panels. In the war years, roll forming technology was used to produce structural parts of aircraft; After the war, roll forming technology was used to produce lightweight metal profiles for construction. With the development of automobile industry and the popularity of electrical equipment and household appliances, roll forming technology has developed rapidly. As one of the most efficient steel forming methods, roll forming technology plays an important role in the development of many industries. Roll forming technology itself requires designers to have a high level of technical experience in designing rolls for the production of certain products. About 30 years ago, the focus of roll forming research in Japan was to grasp the law of forming defects in order to improve the technical requirements of products. With the development of computer technology, the research on the computer-aided design of roll shape, the simulation of plate deformation process in each pass, and the analysis of stress-strain in the process of roll forming have been developed. In 2003 and 2005, German and Japanese scholars proposed a revolutionary new roll forming technology [1][2]. This paper introduces the newly developed flexible roll forming machine for the production of variable cross-section products

key words: flexible roll forming machine, flexible roll forming machine processing products, roll forming technology development history

1 demand for flexible roll forming machine

comparison of two bending methods

there are two main bending methods used to produce open and closed section products. One is the roll bending method to realize bending by rotating the die, and the other is the stamping method to realize forming by reciprocating stamping movement. Compared with stamping forming method, roll forming method has many advantages in technology, economy and Ecology:

high production speed

low cost of forming machine

can process high-strength metal plates

can produce long-size products

low noise

market trend of the automotive industry

nowadays, the products used in the automotive industry require light weight, good quality, personalized customization High economic efficiency and environmental safety. In order to reduce exhaust emissions and produce vehicles with optimal load, and promote the independent innovation ability of enterprises in the base? The industry has carried out extensive research on light vehicles. Customized products are processed in several steps by non flexible methods, which makes the processing cost higher. Therefore, the improvement of molding machine and processing technology is very important. After improvement, the roll forming method is more suitable for the production of some products than the stamping method, for example, the variable cross-section middle column components used at the top and bottom of the car shown in Figure 1. High strength steel is used in load optimization vehicles, which is regarded as a kind of lightweight production. Figure 2 shows a sample of high-strength steel

Figure 1 sample of variable cross-section parts on the automobile

Figure 2 several materials used in the automobile

development of flexible roll forming machine

due to the increasingly extensive application of high-strength steel, the development of forming technology has taken speed as the primary consideration to discuss the most innovative packaging shape, materials and design process with customers. However, when the thick high-strength steel is formed with a press, cracks are likely to appear at the corners. This is one of the main reasons why there is an urgent need to develop a flexible roll forming machine recently. This paper introduces the driving system of a flexible roll forming machine and the samples processed by experiments

2 design of product shape and control system

the section of the product processed by the traditional roll forming machine is limited to keeping unchanged along the axis direction. The interface outline of the products processed in this experiment is variable, as shown in Figure 3. The control system used to produce the roll forming machine with variable cross-section is shown in Figure 4. In the figure, (1) is a steel plate divided by a slitter, (2) is a rotary encoder for measuring the feed speed of steel plate, (3) is a linear encoder for measuring the change of steel plate width. Based on the measured value of this encoder, the CPU (4) will generate control parameters. The rotation or translation movement of the frame can be realized by being controlled by servo motors (5) and (6). (7) It is an induction motor used to drive the roll

Fig. 3 sample processed by experiment

Fig. 4 control system of flexible roll forming machine

3 single and tandem flexible roll forming machine

single flexible roll forming machine

as shown in Fig. 5, the single flexible roll forming machine is composed of the following parts: a forming frame equipped with a pair of rolls, two servo motors for rotation and translation, 6 sensors for detecting the position of the workbench And an executing agency. The forming frame inclined at about 30 degrees to the base is a cantilever frame. This inclined frame can easily process the bending angle of the flange. In the process of designing a single flexible roll forming machine, there are two important points: first, the bending angle of the top and bottom of each roll must be on the axis of the rotating table; Second, in order to process the irregular contour, the rotation axis of the forming frame should be perpendicular to the bending edge

tandem flexible roll forming machine

Figure 6 shows a three frame tandem flexible roll forming machine, which can process products with variable cross-section and constant flange height. The roll inclination angles of the three stands are 20, 40 and 60 in turn. These rolls are driven by induction motors. The conventional rack in front of the three

tandem racks is used to feed plates. The side guide rod is used to avoid the lateral offset of the plate in the processing process. This system makes the rotation or translation motion of the three tandem racks have the same behavior and time delay

Figure 5 single flexible roll forming machine

Figure 6 three rack tandem flexible roll forming machine

trigger control board operation

three rack tandem flexible roll forming machine is driven and controlled by a trigger control board, which controls the distance from the linear encoder to each rack, the flange width, the initial width of the plate, and the drive speed of the induction motor

4 acquisition and analysis of experimental results

the processing sample of the tandem flexible roll forming machine

the sample is shown in Figure 3, in which the plate thickness is 0.5mm, the flange height is 10mm, the maximum width is 140mm, and the minimum width is 90mm. The length of the product is 1, with excellent performance of 820mm. It can be seen from the experimental results that the sample has slight deformation and distortion at the web, while there is no edge wave at the flange. When the sample is placed on the platform for distortion removal, the boundary wave phenomenon appears at the flange of the convex sample, while the boundary wave phenomenon does not appear at the flange of the concave sample. The edge wave and flatness problems of products with a flange height of 17mm are more obvious in the forming process

if the rotation and translation of the forming frame are not synchronized with the feeding movement of the plate, or the gap of the guide rod is too large, the product with the same flange height cannot be processed. Table 1 shows the flange height of different parts of the sample when the guide rod gap is adjusted to 1.5mm

shape defect analysis

Figure 7 shows a paper model describing the mechanism of edge waves. It can be seen from the figure that the flanges of the raised parts of the product will overlap, while the concave parts will have openings. It can be seen from the paper model that the overlap is caused by pressure. Pressure causes edge waves, which makes the sunken part of the product consistent with the paper model. On the other hand, tension will work at the opening. The distortion of products is considered to be caused by the combined action of tension and pressure. Table 1 flange width of variable cross-section products before and after improvement Figure 7 paper model used to describe the mechanism of shape defects

outlook for flexible roll forming machine

roll forming is characterized by high productivity and can provide appropriate technical and economic benefits. Therefore, many materials used in civil engineering and construction industries are processed by this molding method. Particularly noteworthy is the processing of light materials. More and more high-strength material parts on automobiles need to be processed by roll forming technology because it is difficult to use presses

Figure 9 shows a new roll forming machine composed of next-generation components. First, the traditional frame is used to determine the shape of one side of the strip boundary and ensure the feed speed, such as the dynamic mechanical state of the tire, such as force and deformation. Secondly, the flange is processed by cutting the other side of the strip with a controlled gas plasma cutter. Thirdly, the flange edge is bent by the tandem flexible roll forming machine, in which the signal used to control the tandem frame and the signal used to control the air plasma cutting machine are the same signal. This system can continuously process the strip into variable cross-section products

Figure 9 new roll forming machine production line

6 thanks

this article is supported by grant in – aid for scientific research by Amada foundation for metal work technology. The author would like to thank oota seisakusho

7 references

[1] A: "study on development of intelligent roll forming machine", proceeding of 8th International Conference on technology of plastics, October, 2005

[2] oche, n Breitenbach, ckel, ttler：“New Tooling Concepts for Future Roll Forming Applications”, 4th International Conference on Industrial Tools, April, 2003(end)