利用超声波检测无缝钢轨温度应力方案的研究

【作者】 彭小丹；

【导师】 丁杰雄；

【作者基本信息】 电子科技大学 ， 机械电子工程， 2005， 硕士

【摘要】 本文介绍了一种基于声弹性原理测量焊接长钢轨温度应力的方法及智能仪器的设计。钢轨是铁路交通系统中一个非常重要的组成部分。随着环境温度的变化,暴露在野外的钢轨,在其内部产生温度应力。过大的温度应力会导致钢轨变形,威胁到列车的运行安全。多年来各国均在开发、研制用来检测钢轨温度应力的方法和装置,但是至今尚未研制出公认、通用的检测仪器。本文采用超声波无损检测方法设计应力检测装置,并对系统软硬件各部分进行了全面研究。1、论文对基于声弹性原理的温度应力测量方法进行理论推导,得出适用于测量应力的超声波型和理论公式。2、测量系统充分利用了较完善的转换电路和单片机技术,提高了系统的性能指标,增强了系统的功能。3、为测量系统建立了较完善的智能化软件构架,其具有温度补偿和自动校准等特性,提出了采用高精度时间测量芯片来改进测量精度的方法。钢轨温度应力检测仪的研制开发适应了准确快速测量的需求,具有体积小、成本低、可靠性高、响应速度快等特点,具有良好的推广价值。更多还原

【Abstract】 This paper presents the method based on acoustoelasticity theory to test longitudinal temperature stresses in the continuously welded rails and design of the intelligent stress measure instrument with the ultrasonic. Rails are the important part of railroad. While rails temperature alone with environment temperature, the longitudinal forces may be created in the rails. Oversize stresses will cause the rail bent or ruptured, which seriously influence the safety of railroad. In resent years, many measurement methods and measure instruments were developed to test longitudinal thermal stresses of continuously welded rails. However, simple, universal and effective instruments or methods don’t appear up to now. This paper present a measurement method based on acoustoelasticity theory and the general study of displacement sensor, interface circuit and software arithmetic. 1. The paper presents a theoretic deduce to the stresses measurement based on acoustoelasticity theory, and worked out the mathematic formulas of the measurement. 2. The design of measure instrument sufficiently applied the technology of new type ultrasonic signal convert circuit and micro controller, which can improve the function and capability of the instrument. 3. Designed perfect intelligent software for measure system. The software actualized auto-adjust, auto-plus control and temperature expiate, and so on, which father improves the measure precision. The development of this new type instrument of temperature stresses fulfilled fast and precise measurement. The instrument has the characteristics of simple, low cost, credible and fast responds, which make the instrument having applied value.更多还原