Dimension measurement of hot large forgings with a novel time-of-flight system

The dimension measurement of hot large forgings is necessary for process control and product quality. However, the conventional technique in forging plants leads to a high scrap rate of raw materials. In order to reduce the waste and increase the productivity, this paper presents a novel measurement technique based on the pulsed time-of-flight (TOF) laser radar to measure the dimensions of hot large forgings. The system consists of a TOF, a scanning device of the two-degree-of-freedom (2-dof) spherical parallel mechanism (SPM), and two motors. Then, its measuring principle and the SPM are described. A special data-processing method is developed to extract the dimensions and the shape of a large forging by scanning for a few times. The laboratory experiments indicate that the shape and dimensions such as the diameter and length can be achieved by virtue of the TOF system. The dimension measurement in a forging plant is also conducted to verify the effectiveness of the presented system.     

Study of void closure in hot radial forging process using 3D nonlinear finite element analysis

Hot radial forging is used to reduce porosity and increase strength for large-diameter billets. The goal of this research is to study void closure behavior in the hot radial forging process. A nonlinear coupled finite element model is developed to investigate the deformation mechanism of internal void defects during the hot radial forging process. The model is formulated in a three-dimensional frame and a viscoplastic material model has been used to describe the material behavior subjected to large deformation and high temperature. A global–local technique is employed to obtain accurate solutions around the void region. The effects of void location, mandrel, die shape, and the reduction of the tube thickness on the final void reduction are systematically investigated. The predicted reductions for central longitudinal voids in hot upsetting and hot rolling processes are in good agreement with experimental findings. The simulation results provide a valuable procedure for the design of porosity reduction during the hot radial forging process.     

An improved online dimensional measurement method of large hot cylindrical forging

The dimensional measurement of large forgings under high temperature plays an important role in product control. Cylindrical forgings belong to the important products in the forging workshop. In this paper, an improved online measurement method based on binocular vision for the dimensions of hot cylindrical forgings is proposed. Firstly, images of hot cylindrical forgings are captured by two CCD cameras, and the distorted light stripes projected onto hot cylindrical forgings can be resolved from the image by the deviated stripe model. Then, an accurate sub-pixel extraction algorithm of center points of the light stripes is developed for making the extraction of center points of the lights stripes more accurate. Moreover, for changing the field of view of cameras to measure different sections of forgings in the process of manufacturing, the fundamental matrix F is automatically calculated by matching the intersecting points of the projected light stripes in different images, without interrupting the forging process. Finally, experiments on measuring the diameters of hot cylindrical forgings in the workshop are conducted, and the experimental results indicate that the proposed measurement method is effective. Besides, an additional experiment in the laboratory verifies that the relative error of measuring diameters by the presented method is less than 0.7%.     

罐式集装箱罐体用不锈钢板表面质量控制研究

从提高罐式集装箱的原材料---316L不锈钢板表面质量的角度出发,通过对不锈钢冷轧过程中乳化液相关参数的优化,开发了一套适合于罐式集装箱用不锈钢原板的表面质量综合防治技术,并直接应用于现场,获得了良好的效果。     

板型仪在带钢质量检测控制中的应用

带钢板型优劣是影响产品质量的重要指标,而仪表与TDC相结合能够实现热连轧的精确检测和闭环控制;凸度仪和平直度仪能够提供精确、稳定的钢坯质量反馈数据来源,通过闭环控制,提高了板型质量;采用控制参数的自适应优化保证了控制的精度;对于钢坯板形控制有着良好的借鉴价值。     

自走式喷灌机动力双金属水压缸体的研制

叙述了自走式喷灌机水压驱动的技术特点，提出用双金属复合管制作水压缸体的优点、可行性和加工方法，通过自走式喷灌机水压驱动缸体的研制和实际应用，表明该技术应用于水压驱动领域是有效的。     

基于ADE7758计量芯片的多功能电能测量表设计

电力远程自动抄表系统的实施,可以极大地提高抄表工作的效率,节约大量人力和物力。应用电能计量专用芯片ADE7758设计电能测量表,采集数据准确,控制功能灵活、性价比高、工作稳定可靠。本文进行了基于ADE7758的多功能电能测量表的总体设计,着重设计了接口单元的硬件设计和测量仪的软件设计。     

热轧带钢在线测宽技术的发展现状

热轧带钢在线测宽技术是以光电探测技术为基础，将光学、微电子学、电子学、计算机学和精密机械等学科技术融和为一体。国内科研机构开展了对测宽仪的技术开发，并投入生产线使用，获得了较好的经济和社会效益。     

基于激光扫描的大锻件三维尺寸测量

锻压过程中对大锻件的准确快速测量能提高大锻件的制造能力和减少资源浪费。本文介绍了基于双轴直角坐标运动执行机构和激光扫描测距传感器的测量系统,实现热态锻件尺寸的快速准确测量,采用椭圆的最小二乘法拟合锻件截面并获取锻件关键尺寸,并计算锻件轴线直线度并进行误差分析。通过实验验证该测量方案的可行性和重复性。     

用Minitab进行测量系统分析

以滚动轴承制造现场使用的D0 12轴承检测仪的“GR&R”研究为例 ,介绍用Minitab进行测量系统分析的方法 ,并以分析数据为依据对测量仪器作相应的调整和改进