自动标准压力发生器控制原理及检定方法研究

压力发生器以其准确度等级高、操作简单、可自动检定等优点被计量检定部门作为计量标准器使用。它与数字压力计区别是具有测量功能和控制功能。测量功能是数字压力计具备的功能,控制功能是压力发生器所独有的功能。本文通过对控制功能的工作原理研究提出了一种能够提高控制功能的方法。并结合检定软件和检定数据进一步诠释检定规程的要求,对更好地开展检定工作具有一定的参考价值。     

无线压力记录器校准及其测量不确定度评定

详细分析了无线压力记录器示值误差的校准方法及其不确定度来源,并以MPⅢ型压力记录器为例,遵从JJF 1059.1-2012《测量不确定度评定与表示》所推荐的评估方法,评定以0.05级数字压力计为标准器校准压力记录器时示值误差的扩展不确定度,为数字压力计校准无线压力记录器时示值误差的不确定评定提供了范例.     

数字压力计检定中高度差测量的研究

正一、概述在高精度数字压力计的检定过程中,标准器和被检仪器之间受力点的垂直高度差会引起压力差,因此在检定准确度较高的数字压力计的过程中需要进行压力补偿,JJG875-2005《数字压力计检定规程》在附录D作了如下规定:"检定中,标准器与压力计的受压力点,应在同一水平面上,当两者不在同一水平面时,因介质高度差引起的检定附加误差不应大于压力计允许误差的十分之一,否则,应对介质高度差引起的     

如何选择数字压力计检定压力表

JJG 52—2013《弹性元件式一般压力表、压力真空表和真空表》检定规程发布实施后,数字压力计可以作为检定压力表的标准器来使用。文章介绍了如何根据数字压力计的最大允许误差和测量范围来确定标准器的选择。     

压力变送器测量结果不确定度评定

一、概述1.测量依据JJG882-2004《压力变送器》检定规程。2.测量环境温度为23℃;相对湿度为56%。3.测量标准用活塞压力计和智能数字压力校验仪作为测量标准。活塞压力计的主要技术指标:测量范围为(1～60)MPa,准确度等级为0.05级。智能数字压力校验仪的主要技术指标:测量范围     

不确定度评定实例分析 工作用U形液体压力计示值误差的不确定度评定

<正>一、概述1.测量依据JJG540-1988《工作用液体压力计检定规程》。2.环境条件工作用1.0级U形液体压力计检定环境温度为(20±10)℃,相对湿度小于85%,应在检定环境条件下放置2h。3.测量标准标准器为智能数字压力校验仪,最大允许误差为±0.05%FS。     

福禄克公司计量校准部推出两款重量级新品——2700G系列高精度高性能数字压力计和3130便携式气体数字压力校准器

2013年8月,美国福禄克公司计量校准部推出两款重量级压力系列新品——2700G系列高精度高性能数字压力计和3130便携式气体数字压力校准器。2700G系列数字压力计产品使用简单方便、精准稳定,是各类压力计量校准实验室最理想的压力校准仪表。2700G系列高精度数字压力计可以和福禄克的各种压力泵配套使用,从而构成完整的压力校准解决方案。2700G系列数字压力计的准确度为满量程的0.02%,是目前业界便携式压力计准确度最高的标准压力计,     

福禄克公司计量校准部推出两款重量级新品——2700G系列高精度高性能数字压力计和3130便携式气体数字压力校准器

新型数字压力计2700G系列产品使用简单方便,兼顾耐用,精准稳定,因此他们是各类压力计量校准实验室最理想的压力校准仪表：·2700G系列高精度数字压力计可以和福禄克的各种压力泵配套使用,从而构成完整的压力校准解决方案。·2700G系列数字压力计的准确度为满量程的0．02％,是目前业界便携式压力计准确度最高的标准压力计,且稳定性很好。     

自动标准压力发生器示值误差的测量不确定度研究

使用0.005级气体活塞式压力计对0.02级自动标准压力发生器进行校准。阐述了自动标准压力发生器示值误差的测量的不确定度评定方法,提出了示值重复性和分辨率引入的不确定度分量应取其中较大者,感压面高度差引入的不确定度分量应考虑压力变化对气体传压介质密度的影响;分析了合成不确定度中各分量的权重:标准器引入的不确定度分量为主要的合成不确定度来源,随着校准点压力值的增加,重复性/分辨力引入的不确定度分量权重显著减小,感压面高度差引入的不确定度分量权重在400kPa校准点以上,超过重复性/分辨力成为仅次于标准器的合成不确定度来源。     

一种气体活塞式压力计不确定度评定及性能验证

气体活塞压力计作为一种高准确度压力标准器,主要用气体做工作介质,可测量和校准表压、绝压、真空压力等。本文介绍一种0.01级气体活塞式压力计标准装置,对测量结果不确定度评定进行了分析。通过性能验证,以保证标准装置量值传递的可靠性及准确性,可供相关计量工作参考。     

Design and Validation of the MBW Standard Humidity Generators

MBW Calibration AG (MBW) is the Designated Institute (DI) for humidity appointed by the Federal Institute of Metrology, METAS. MBW currently offers calibration and measurement capabilities (CMC) for frost/dew-point hygrometers by comparison with precision chilled-mirror transfer standards that have been calibrated using the primary standards of leading European National Metrology Institutes or DI. The design, construction and validation of two standard humidity generators to be used as the Swiss national standards for the primary realization of frost/dew-point temperature in the range from ? 90 °C to + 95 °C are presented and discussed. The generators are operated as continuous flow “single-pressure” generators in the range from ? 80 °C to ? 10 °C with saturation over ice and from 0.5 °C to + 95 °C with saturation over water. Additionally, they are used in “two-pressure” mode for saturation over ice down to frost-point temperatures of ? 90 °C and down to ? 20 °C for saturation over water. The main saturators of both generators have been designed to fit in commercially available calibration baths with either ethanol or distilled water as the heat transfer fluid for saturator temperatures below and above 0 °C, respectively. Saturator temperature is measured using standard platinum resistance thermometers and a purpose-built precision thermometer. Pressure measurements are taken with gauge pressure transducers and a separate barometric sensor, to reduce the influence of the atmospheric pressure on the measurement of the pressure ratio and make full use of the correlation of pressure measurements and enhancement factors when operating in two-pressure mode. A totally automated pre-saturation and flow control system facilitates the calibration of state-of-the-art chilled-mirror transfer for standards without manual readjustment of the generated flowrate to ensure a constant volumetric flow at the conditions of the mirror. The uncertainty budget leading to the CMC for frost/dew-point temperature realization is presented in the context of the experimental validation performed. The results in the overlapping range of both generators are presented and used as further evidence of the saturation efficiency of both standards.     

静态膨胀法真空标准容积比测量及不确定度评定

静态膨胀法真空标准是真空计量的基础标准,其校准的精度在很大程度上取决于容积比测量的精度。选用一台高压力气体活塞压力计测量膨胀前气体的压力;利用电容薄膜真空计作为比较器,用一台低压力数字式气体活塞压力计测量膨胀后气体的压力;对静态膨胀法真空标准的容积比进行了测定,并对测量结果进行了不确定度的评定。     

Realization of Negative Gauge Pressure Standard in the National Metrology Institute of Indonesia

Accurate negative gauge pressure measurement is the key factor for many scientific and industrial applications such as clean room technology, medical treatment, and pharmaceutical production. However, there are not much publications regarding to the technical guide when it comes to negative pressure measurement, although several comparison of negative gauge pressure has been performed in Europe. In this study, two methods for negative pressure calibration have been successfully implemented by National Standardization Agency of Indonesia with using pressure balance. The first method is by generating the negative pressure in the bell jar of the pressure balance, and the second method is by using pressure balance in absolute pressure mode and additional barometric pressure measuring instrument. Both methods measurement results show linear relation from the negative to positive pressure and show good agreement by each other with the normalized error (En) less than 0.40 from – 1000 to 1000 hPa with uncertainty up to 0.073 hPa. The expanded uncertainty of the second method is relatively larger due to dominant contribution from the uncertainty of the barometer used. Therefore, it can be concluded that both methods can be used in order to provide traceability for negative gauge pressure measurement instrument in Indonesia.     

用线性真空规测量小孔分子流流导的方法研究

提出了用线性真空规测量小孔分子流流导的方法,该方法利用了线性真空规两次测量压力的比值,避免了真空规测量绝对压力引入的不确定度,从而有效减小了小孔流导的测量不确定度.文章介绍了小孔流导的测量原理、测量装置和测量结果,小孔流导测量的合成标准不确定度为0.29%.     

基于活塞式压力计和数字压力计的微小压力测量新方法

提出了一种微小表压力（差压）测量的新方法。采用1台活塞式压力计和1台精密的数字压力计,通过关断阀连接高低压端的特殊连接方式实现微小表压力（差压）测量,解决了活塞式压力计由于受其下限值的限制而不能实现微小压力测量的问题。利用数字压力计较好的短期稳定性以及活塞式压力计较低的不确定度,可以实现1~10kPa微小表压（差压）的校准,其校准结果的扩展不确定度为U=2.2Pa（k=2）。     

Uncertainty analysis of the high vacuum part of the orifice-flow-type pressure standard

The orifice-flow-type pressure standard is commonly accepted as primary standard for vacuum gauge calibration in the high vacuum gas pressure range. It consists of two parts—a high vacuum part and a flowmeter. Practical questions arising at design of the standard have to be answered based on the standard uncertainty analysis.The analysis of the uncertainty sources in the high vacuum part except deviations from the Maxwellian distribution is given in the paper. Uncertainty of a precise flowmeter is taken from references for comparison. It follows from the analysis that uncertainties caused by some sources at routinely achievable parameters are negligibly small and further improvement brings no benefit. The crucial quantities influencing the total uncertainty are the temperature of the chamber and the flowmeter, the outgassing rate from the inner surfaces, the ultimate pressure of the pump and the additional (detrimental) pumping speed. The pumping speed of the main pump has to be “sufficiently higher” than the orifice conductance.     

标准静态膨胀法真空装置研制

本装置检定范围(10^-3～10^5)Pa，最佳校准能力0．012％～2．2％．可以检定薄膜真空计。热传导真空计以及电离真空计。该装置的建立不仅满足了从大气到10^-3Pa高真空计量的需求，而且还可以用来校准标准漏孔，拓宽了检测领域。     

KJY-II型精密孔径仪的测量不确定度分析

KJY—Ⅱ型精密孔径仪是测量环规内径的专用仪器，已经在环规计量检定规程中(JJG894—95)被推荐为检定二等环规的首选仪器。本文着重分析了仪器的不确定度问题。     

微压力标准装置研制

详细介绍了一种液体压力计微压标准装置的研制,采用超声波液位定位技术实现液位准确定位,并采用激光干涉技术实现了液柱高度准确测量,同时对温度控制、位移控制、数据采集处理等分系统设计进行介绍,最后对微压标准装置进行了测量不确定度分析和验证,该标准装置填补国防系统5 kPa以下微压量值传递空白,解决国防系统高准确度微压仪器仪表...