?? Shandong shunxinda Machinery Co., Ltd. (13969559358) is located in Liaocheng Economic Development Zone, Jiangbei water city with beautiful scenery. It is a company specializing in the production, processing and sales of precision seamless pipe, cold drawn precision seamless pipe and cold-rolled precision seamless pipe
Spot rolling of precision Q345B precision bright tube with elastic-plastic body
The straightening principle is unique, and the two roll straightener is the key equipment for high precision straightening of short round bar. The roll gap formed by the combination of convex and concave rollers can roll and straighten the surface of round timber continuously, which can improve the surface quality of round timber. According to the practical application of roller profile in a factory, there is excessive overlap and gap between the two spiral calendering belts rolled by concave roller on the spot surface of precision Q345B precision bright tube. In the finite element analysis, the two spiral calendering belts are two plastic strain value spiral belts. Therefore, this paper takes the connection status of the two spiral rolling belts as the evaluation index to improve and optimize the concave roller structure of the straightener. Key factors analysis of two roll straightening roll model modeling the main components of two roll straightening finite element model include straightening roll, precision Q345B precision bright tube in stock and front and rear guiding device. In order to simplify the model and reduce the calculation cost, the deformation of the straightening roller and the front and rear guide device on the spot of precision Q345B precision bright tube is not considered. The straightening roller is established as a rigid body model, and the spot of precision Q345B precision bright tube is established as an elastic-plastic body. For the contact treatment between components, the friction property between straightening roller and precision Q345B precision bright tube must be considered, and the friction coefficient should be set to 0.4; The friction between the guide device and the precision Q345B precision bright tube can be ignored. The movement mode of the straightening roll is determined by applying rotation displacement to the coupling reference point of the upper and lower rollers. The precision Q345B precision bright tube moves forward by the friction force with the straightening roller, which is closer to the real situation. Mesh generation is the key to finite element analysis,
In this paper, c3d8r reduced integral element is selected to generate mesh, which is suitable for the analysis of metal contact problems. The precision Q345B precision bright tube is finally divided into 35000 hexahedral units, the overall size of the units is 8mm, which can meet the accuracy requirements. The research object of this paper is the precision Q345B precision bright tube with a thickness of 100 mm. The material is 20Cr, the material yield strength is 540Mpa, the diameter thickness ratio is 10, and the spot modeling length of precision Q345B precision bright tube is 2000mm. The structure of traditional concave roll is improved as shown in Fig. 2. The structure of improved concave roll is composed of straightening area, rolling area, reverse arc and roll end chamfering. Compared with the traditional roll shape, two sections of structure of rolling area and reverse arc R4 are added [3-5]. Lead of precision Q345B precision bright tube in stock. The values are as follows: T = ¦Ð £ä£ô£á£î ¦Á£½ £³£®£±£´ ¡Á £±£µ£° ¡Á 176 ¡Ö 83.05mmt, 85mm. 2.3 calculation of the length of the concave roll's rolling area, the contact area between the concave roller and the precision Q345B precision bright tube is the rolling area of the straightening roll,
The rolling area of concave roll is designed as a straight line which is symmetrical to the left and right and smoothly connects with the straightening area. In Fig. 4, O is the geometric center of concave roller, and the coordinate system oxyz is established, X is the concave roller rotation axis, oxyz is the spot coordinate system of precision Q345B precision bright tube, and X axis is the forward axis of precise Q345B precision bright tube spot rotation. Z-axis and z-axis coincide, and the angle between x-axis and x-axis is the working angle between concave roller axis and precision Q345B precision bright tube spot axis ¦Á¡£ Let HB be the single side rolling area of concave roller, and the single side spiral rolling strip AB with width of 0.5T is formed by rolling on the spot surface of precision Q345B precision bright tube, then OE = AB = 0.5T, and og ¡¬ Hb, the length of both is equal. If of is the projection of og in the horizontal plane of OE, then Fe ¡Í OE, and of is parallel to the concave roller axis, ? foe = ¦Á£¬¦Á The value is 10 ¡ã¡« £±£µ ¡ã£¬ Then: 2.2 rolling principle analysis. In Figure 3, the arrows on both sides of the precision Q345B precision bright tube indicate the contact area between the concave roller and the precision Q345B precision bright tube. The width and pitch of the single side rolling strip (shadow part) of the precision Q345B precision bright tube are 0.5T and T, respectively; The spot of precision Q345B precision bright tube is rotated forward to position A2, and the right contact area rolls the surface layer of the precise Q345B precision bright tube into a right spiral rolling strip, with a width of 0.5T. If the left and right spiral light rolling belts are just staggered and connected to each other as a whole, there will be no disconnection or excessive overlap, It is considered that the concave roller has a better effect on the spot rolling of precision Q345B precision bright tube. Through the above analysis: the distance between the starting positions of the rolling strips on both sides of the precision Q345B precision bright tube should be (n + 0.5) t, where n is an integer. In order to ensure the straightening accuracy, n should be at least 6 , and N = 7 according to the actual roll type; T is the formula: K is the coefficient, the value is greater than 1. Through repeated calculation, it is appropriate to take K as 1.5, that is, the length of the rolling zone is 0.9t. Fig. 5 is the schematic diagram of the starting position of the rolling area on both sides of the concave roller. If O1 and O2 are the starting positions of the spiral rolling strips on both sides of the spot surface of the precision Q345B precision bright tube, the starting distance between the two rolling areas should be AB, ab = O1O2 / cos ¦Á¡£ Taking the precision Q345B precision bright tube with a diameter of 100 mm as an example, ab = O1O2 / cos15 ¡ã£½ £·£®£·£¶£´£¸£ô¡£
?? The company reserves a variety of specifications of precision seamless pipe, cold drawn precision seamless pipe, cold-rolled precision seamless pipe, perennial business in Tianjin, Baotou Steel, Baosteel, Hengyang, Angang, Chengdu, Yegang, Lubao, Anyang, Jiangyin, Hongdu and other high-quality seamless steel pipe, alloy steel pipe, high-pressure boiler pipe, alloy high-pressure seamless pipe, thick wall seamless pipe, fluid pipe, structural pipe, chemical fertilizer special pipe, Petroleum cracking pipe, low pressure boiler pipe, large diameter seamless pipe, large diameter welded pipe, precision steel pipe, etc. The materials of common resources are: 10 ¡Á 10, 20 ¡Á 10, 45 ¡Á 10, 16Mn, 27SiMn, 12Cr1MoV, 15CrMo, 12Cr1MoVG, 15CrMoG, 10CrMo910, 20Cr, 40Cr, 35CrMo, 304, 316, 316L, 310S, 309S, etc.