基于落锤装置的力监测压力绝对校准方法研究  

Research on an absolute calibration method of monitoring pressure by force sensor based on drop-weight device

作　　者：顾廷炜 孔德仁[1] 商飞[1] 陈静[1] 

机构地区：[1]南京理工大学机械工程学院,南京210094

出　　处：《仪器仪表学报》2017年第3期750-756,共7页Chinese Journal of Scientific Instrument

基　　金：国防科工局技术基础科研项目(JSJL2014606B003)资助

摘　　要：在详细探讨了利用落锤装置进行压力校准的多种途径的基础上,针对力监测压力方法中存在的传感器力值测量精度易受预紧力和惯性力影响的问题,提出了一种改进方法,即在落锤装置原有锤头结构的基础上自行研制了高精度的应变式力传感器,推导了通过自研力传感器监测造压油缸内压力的惯性力修正模型,并总结了模型进一步简化所需满足的前提条件。在此基础上分别对传统和自研力传感器开展了多组校准试验,试验结果表明,采用过渡件和螺栓固定等传统安装方式会对力传感器产生附加预紧力和惯性力两方面的不良影响,造成传感器在测量锤头和活塞杆之间的撞击力时产生很大的测试误差;自研力传感器在满足重锤质量远大于活塞杆质量并保证撞击对中精度的前提下,能够直接根据传感器测得的力值和活塞杆横截面积计算出缸内的压力,和现有的比对式准静态校准方法相比,其高压段压力监测精度优于1%,可作为一种有效的压力校准方法。Various methods for pressure calibration by drop-weight device are discussed in detail. The measurement accuracy of force sensor is easy to be influenced by pretightening force and inertia force. An improved method to enhance the measurement accuracy is proposed. A high precision force sensor is designed based on the structure of the original weight,from which the inertia force correction model of absolute calibration is derived. In further,the model simplification conditions are summarized. Calibration tests are carried out and the experimental results show that traditional installation methods of transition parts connecting and bolt fixing generate additional adverse effects of pretightening force and inertial force. As a result,relatively large error exists during the measurement of impact force between weight and piston rod. In contrast,pressure can be calculated directly by measuring values of force sensor and cross-sectional area of piston rod,under the conditions that the mass of weight is far greater than piston rod and high precision of central impact.Compared with the existing quasi-static calibration method,the monitoring accuracy of high pressure is improved larger than 1%,which can be regarded as an effective pressure calibration method.

关 键 词：压力计量 落锤装置 力监测压力 绝对校准 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置] TJ012[自动化与计算机技术—控制科学与工程]