150mL活塞式液体微小流量计量标准装置的研究

摘要

针对现有液体流量计量标准装置测量范围的限制不能适应微流体计量的需求,研究开发了一种用于生物医药领域的150mL活塞式液体微小流量计量标准装置.介绍了该标准装置的结构、检定原理和检定过程；根据检定需求设计了一种基于LabVIEW平台和PLC的检定系统软硬件.利用LabVIEW平台设计上位机的检定程序,用于实现人机交互、检定流程控制、检定数据的存储和报表生成等功能.采用可编程逻辑控制器(PLC)作为下位机控制核心,用于实现运动控制、变送器信号的采集、光栅尺计数和阀门控制等功能.进行了标准装置与高精密电子天平的比对实验和重复性分析,证明该装置一致性能达到0.124％、重复性优于0.032％.%Aiming at the constraints of the measurement range of the current liquid flow measurement standard device cannot adapt to the requirement of micro-fluidic measurement, a liquid micro-flow measurement standard device with 150 mL range is proposed. The structure of the standard equipment, critical principles and certification process are described. The software and hardware of the metrological verification system based on Lab VIEW and PLC are designed according to the critical requirements. By using the test program of the upper machine designed on the LabVlEW developing platform,the functions regarding human-computer interaction,calibration flow control, storage of test data and test report generation are realized. By using programmable logic controller ( PLC ) as the cybernetics core of the lower machine, the functions regarding motion control, transmitter signal acquisition, grating bar counts and valve control are realized. Comparative experiments and repetitious analysis are conducted between our standard device and high precision electronic balance,the results of our standard device demonstrate consistent performance is 0.124 % , repeatability excels 0. 032 % .