Research And Design On Efficient Combination Type Water Flow Standard Facility

The flow rate standard facility not only is the reference of unifying and transferringthe flow rate unit, but also is widely used as the experimental device. The researchand application of it is an important part of the development of flow rate measurementand test technology.There are a lot of works on meter calibration, and test tasks during new productdevelopment in the company of flow meters manufacture. So, the flow rate standardfacility should be not only enough in accuracy and reliability, but also it should beefficient. In view of the characteristics of industrial application fields, an EfficientCombination Type water flow rate standard facility is researched and designed in thisthesis. With the nature of high efficiency, small cost and high degree automation, thisfacility is able to calibrate or test different varieties velocity type flow meters.The structure of Efficient Combination Type is put forward in this facility. Areasonable collocation of the Static Weight method and the Master meter method ismade by this structure from the points of system scale and uncertainty synthesis, as aresult, the on-line calibration of the master meter is realized, with same accuracy ofmeasurement the scale of the Weight part is reduced, the total cost of the facility isdecreased also.The control subsystem of this facility is developed by MCGS5.5 (Monitor andControl Generated System), which completes many functions such as the calibrationsof flow rate facility self and varied types flow meter, data save, inquiry of historicdata, report and print, and so on. The graphic interface with effect of animation makesthe operation of this facility is easier. The hardness of operator's work has beenreduced with the automatic process of calibration. Combined the Visual Basic 6.0, theproblem of real-time measurement for MCGS is solved, as a result, the accuracy ofmeasurement is assured.The application of the convert-frequency technology in standard flow rate is studiedin this thesis. The convert-frequency velocity regulation subsystem of the facility isdeveloped by the mode of convert-frequency loop, and the convert-frequency controlof the flow rate regulation is realized in whole range of calibration flow rate. Based onthis, the design scheme of muti-converter velocity regulation system is put forward,which is with better effect of energy conservation.Now, 300 or more than flow meters have been calibrated on this facility. It isconfirmed by the operation status and the experimental data that every technologycriterion has reached the design requirements, and the scheme of EfficientCombination Type water flow rate standard facility is reasonable.