无线监测示功仪的研制与应用

针对常规示功仪资料储存的容量有限和对油井不能长时间连续监测的不足,研制了无线监测示功仪。该示功仪将载荷和位移传感器、无线传输以及太阳能供电等多种技术集于一体(1)采用加速度传感器,实现了光杆无线位移检测,解决了常规位移传感器寿命短、可靠性差的问题;(2)应用CC1000无线模块,实现了油井示功图短距离数据无线交换,屏弃了常规仪器电缆通讯的方式;(3)通过增加仪器储存容量和移植USB接口,解决了常规示功仪储存数据量少的问题,极大地方便了数据交换;(4)将太阳能电池与充电电池有机结合,圆满解决了仪器供电问题。     

基于ZigBee的矿用应力监测系统的研究

提出了一种新的煤矿巷道监测方法 ,即采用测力锚杆对巷道顶部深处的应力变化进行定时监测。系统主要分为三部分:传感器节点、通信主站和上位机。传感器节点负责采集和上传数据,数据主站负责管理各传感器节点并存储和上传数据,上位机负责汇总各传感器数据并对其进行分析处理。     

积石峡水电站溢洪道堰闸段工程中锚索测力计的应用

文章简述了积石峡水电站溢洪道堰闸段锚索测力计的设计布置、率定检验、安装方法及张拉过程中对测力计的观测等方面,以加强锚索测力计在锚索张拉施工过程中的质量控制。     

Development and application of a multi-axis dynamometer for measuring grip force

Objective: This paper describes the development and application of a novel multi-axis hand dynamometer for quantifying 2D grip force magnitude and direction in the flexion-extension plane of the fingers. Methods: A three-beam reconfigurable form dynamometer, containing two active beams for measuring orthogonal forces and moments regardless of point of force application, was designed, fabricated and tested. Maximum grip exertions were evaluated for 16 subjects gripping cylindrical handles varying in diameter. Results: Mean grip force magnitudes were 231 N (SD = 67.7 N), 236 N (72.9 N), 208 N (72.5 N) and 158 N (45.7 N) for 3.81 cm, 5.08 cm, 6.35 cm and 7.62 cm diameter handles, respectively. Grip force direction rotated clockwise and the centre of pressure moved upward along the handle as handle diameter increased. Conclusions: Given that the multi-axis dynamometer simultaneously measures planar grip force magnitude and direction, and centre of pressure along the handle, this novel sensor design provides more grip force characteristics than current sensor designs that would improve evaluation of grip characteristics and model-driven calculations of musculoskeletal forces from dynamometer data.     

Development of in situ system to monitor the machining process using a piezo load cell

The measurement of cutting force is one of the most frequently used techniques for monitoring machining processes. Its widespread application ranges from tool condition identification, feedback control and cutting system design to process optimization.This paper suggests another system for measuring cutting force in milling processes. Generally, tool dynamometers are taken into account for the most appropriate cutting force measuring tool in the analysis of a cutting mechanism. However, high prices and limited working space make in situ systems difficult for a controllable milling process. Although an alternative suggestion is to use an AC current from a servomotor, it is unsuitable for cutting force monitoring because of a small upper frequency limit and noise.The suggested cutting force measuring system is composed of two piezo load cells placed between the moving table bracket and the nut flange of the ball screw. It has many advantages, such as lower cost and a wider measurement range than the tool dynamometer, over using the built-in feeding system and the low-cost piezo load cell for applying a conventional machining center.This paper focuses on the performance test of a newly developed measuring system. By comparing the cutting force between the tool dynamometer and the system developed from a series of end milling experiments, the accuracy of the cutting force measurement system was verified. Linearity, transverse sensitivity and the upper frequency limit of the system were verified by experiment.     

汽车测功设备配电设计的优化

通过对汽车底盘测功机及发动机测功机工作原理及发动机测功试验原理和方法的了解,结合供配电设计的基本原则和方法确定出合适的负荷计算需要系数、功率因数、计算负荷、计算电流等电气参数,为变压器、配电开关、电缆线路等设备及线路的合理选择提供设计依据,从而实现测功机配电设计的优化,在满足设备正常运行的条件下,达到节能、节约设计的目的。     

高速水力测功器安装机架的动静态结构特性分析

在高速水力测功器功率加减载测试系统中,发动机所产生的功率在被其吸收与测试的过程中会产生不平衡动态载荷,为了吸收在高速水力测功器中所产生的振动能量,其安装机架的强度与刚度必须满足技术要求。根据某型高速水力测功器的相关技术参数要求对其机架进行设计,随后应用ANSYS软件建立高速水力测功器机架的计算模型,并进行有限元计算,确保机架能够满足各向刚性和最低自然频率的要求。此外,采用试验测试手段得到安装机架在设备载重状态下的固有特性,并与数值结果进行对比,其最大误差不超过5%,表明数值计算方法的有效性。在此基础上,系统地研究机架的动态响应特性,为更好地确保整机的安全运行提供了依据。     

异步测功机组的设计、制作及使用

随着电动工具行业的发展,对电动工具功率测试精度的要求也在提高,针对电动工具性能测试的需要,设计、制造了异步测功机组,使我单位的电器检测室的电动工具的检测能力得到了提高,保证了监督检验任务的完成。     

应用迭代阻尼系数提高泵况诊断准确率

抽油机井示功图是了解有杆活塞泵工作状况的主要手段,实现抽油机井功况的智能诊断是油田数字化、智能化管理的目标。1966年Glbbs S方程的建立,为示功图的智能诊断提供了理论依据。在应用泵功图作为诊断依据时,影响计算泵功图几何形状最主要的因素为阻尼系数。通过对确定阻尼系数计算方法的探讨,给出适合大庆油田阻尼系数的计算方法,从而进一步提高了智能诊断的准确率。     

示功图频谱分析新方法

示功图分析法是目前常用的抽油井故障诊断方法.由于受到复杂的井下工况的影响,示功图时域信号往往会出现极大变形,从而令示功图分析结果出现错误.为解决这一问题,对示功图时域信号进行了频谱分析.利用将时域信号转换为频域信号的方法,研究了各种频率的能量分布及信号的规律性.分析了示功图频谱的影响因素以及典型工况频谱特征,建立了示功图模糊数学识别模型,并给出了示功图频谱分析方法的步骤.用40多口油井示功图进行了验证,结果表明,频谱分析新方法可用于示功图的识别.