多声路超声波流量计校准及相关问题探讨

为了标定UF-911超声波流量计的测量精度,在国家水大流量计量站利用静态容积法进行了一次针对实际泵站的模型试验和一次准确度标定试验.结合这2次试验,对其校准过程、测量数据、误差等内容进行了简单的介绍和分析,对超声波测流方法的实验室校准以及实际工程应用中的相关问题进行了探讨,对超声波流量计的工程应用具有一定的指导意义.     

Sub-surface damage investigation by high frequency ultrasonic echography on 100Cr6 bearing steel

This paper presents an original ultrasonic technique devoted to the early detection of sub-surface fatigue cracks in 100Cr6 bearing steels. Echographic experiments were carried out during interrupted rolling contact fatigue tests. Crack initiation and crack propagation stages were both investigated. Quantitative measurements of sub-surface crack position, depth and angle with respect to the bearing surface are presented. Experimental results are analysed and discussed in relation to rolling contact fatigue theories. Contrary to what is generally accepted the presented results show that the crack propagation stage could represent an important part of bearing life.     

用超声波检测信号预报抽油杆剩余寿命

目前研究抽油杆剩余寿命的理论方法没有一种可直接应用于现场,无法直接通过工程检测手段来判断抽油杆的剩余寿命。为此,通过抽油杆疲劳试验,找出裂纹前缘的变化规律,得出裂纹深度与裂纹面积之间的关系、裂纹面积与剩余寿命的关系,借用传统Paris公式的数学模型,通过超声波检测建立了超声波探伤信号与裂纹深度之间的关系式,即裂纹检测信号与裂纹扩展规律之间的关系,从而提出了直接利用超声波探伤信号确定抽油杆剩余寿命的方法。将研究结果与疲劳模拟试验得出的剩余寿命相比较,寿命预测符合率达84%以上。     

电厂碳钢蒸汽管道石墨化诊断

本文对碳钢蒸汽管道石墨化常用的诊断方法——金相分析法、化学分析法、机械性能试验法进行了探讨。并将密度法、超声波法应用于石墨化的诊断,实验证明密度法和超声波法用于石墨化的诊断是可取的。     

Study on Desorbing Sulfur Dioxide from Citrate Solution by Ultrasonlficatlon

Using a sonochemical reactor designed by the authors, the process of removing sulfur dioxide from citrate solution simulating the flue gas desulfurization was studied. The influence of ultrasonic frequency, ultrasonic power, reaction temperature, stirring speed, inert gases, initial concentration of sulfur dioxide and concentration of citrate on the efficiency of sulfur dioxide desorption, the stability of citrate solution and the concentration of sulfate radical was examined systematically. By comparing the desorption of sulfur dioxide with and without ultrasonification, it was concluded that （1） lower ultrasonic frequency results in a better degassing efficiency; （2） the use of ultrasonification in desorbing sulfur dioxide from citrate solution improves the desorbing efficiency in some conditions, without changing the essence of chemical reactions; （3） sparging inert gas into the liquid can lower the viscosity of solution and the cavitating threshold, and raise the desorption efficiency. These results demonstrate a technical way for deep desorption of sulfur dioxide and provide the fundamental data for future industrial disposal of sulfur dioxide.     

驻波场原油破乳脱水的研究

以鲁宁管输原油为研究对象,在实验室考察了影响原油破乳脱水的几个重要参数,如破乳剂用量、沉降时间和驻波场中的声强、超声波处理时间等。用正交试验分析了各因素的影响程度,得到依影响大小的排序为沉降时间>驻波场声强>超声波处理时间;驻波场中原油脱水的最佳试验条件为,加入破乳剂20μg/g,在搅拌器转速约400r/min下搅拌5min后,用声强0.225W/cm2超声波处理5min,在80℃水浴中沉降120min,在此试验条件下原油含水率(体积分数)由1.40%降为0.07%。     

基于超声波的车载土石方计量系统

为了测量车载土石方，针对土石方不规则的形状，利用超声波的发送和接收电路、TR4016系列传感器阵列和TI公司的TMS2812DSP一起构成了超声波车载土石方计量系统。对该系统的硬件设计、软件流程进行了介绍，并对实验误差进行了分析。     

混凝土结构抗冻性超声检测方法的研究

依据固体结构动弹模与表面波速度的本构关系，采用超声波技术检测混凝土冻融试件的动弹 模，并 与共振法测出的动弹模进行对比，总结出其内在相关规律，建立起预报混凝土动弹模的回归 方程，由测得 的波速计算出相应的动弹模，再利用动弹模之比评定出混凝土结构的抗冻性。通过初步试验 和检测方法的研究表明，此研究方法思路切实可行，可供混凝土耐久性检测工程参考。     

Metrological Provision of Ultrasonic Defectoscopes for General Purposes under Production and Operating Conditions

Objective data for determining defect parameters with the aim of optimizing monitored characteristics during operation of general purpose modern ultrasonic defect detectors in-situ are systematized. The redundancy of periodic verification by the Russian State Standards Organization of ultrasonic defect detector and piezoelectric transducer parameters is demonstrated. Recommendations are given for improving standard documents.     

环形直线行波超声电机定子的模态分析

针对一类环形封闭式的行波型直线超声电机定子的振动模态进行了有限元与实验研究。该类电机的定子由两个半圆环和两段直梁构成。分析了有限元的单元尺度对固有频率及频率差的影响以及压电陶瓷片的粘贴位置对固有频率及弯曲振型的影响。对自行研制的超声电机进行了实验研究。实验结果表明，固有频率差的数值计算值与相应的共振频率之差吻合。