Abstract High accuracy mass flow measurement is an enabling technology at the base of many industries. HORIBA STEC Co., Ltd. developed its own primary gas mass flow measurement system. We employed the dynamic gravimetric method in a vacuum chamber, and we use only mass and time information for mass flow rate calculation, with no correction for temperature, pressure and humidity. The system achieved 0.036% uncertainty as lowest of results with satisfactory performance of proficiency testing with NIST (National Institute of Standards and Technology). Then the laboratory has been granted ISO/IEC 17025 accreditation since 2017. This paper describes the system details and uncertainty analysis.

中文翻译：

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用于气体质量流量测量的主要动态重力测量系统

摘要 高精度质量流量测量是许多行业基础的使能技术。HORIBA STEC Co., Ltd. 开发了自己的初级气体质量流量测量系统。我们在真空室中采用动态重量法，我们只使用质量和时间信息来计算质量流量，没有对温度、压力和湿度进行校正。该系统实现了 0.036% 的不确定性，是 NIST（美国国家标准与技术研究院）能力验证结果令人满意的最低结果。然后实验室从2017年开始获得ISO/IEC 17025认证。本文描述了系统细节和不确定性分析。