ISO 17025 ACCREDITATION FOR A STANDING START FINISH (SSF) PRIMARY FLOW STAND AND THE APPLICATION TO USING CORIOLIS FLOWMETERS AS REFERENCE STANDARDS
Mark Lee, Aart Pruysen
Abstract:
At FLOMEKO 2000 Micro Motion, Inc. (MMI) reviewed the concept of Transfer Standard Method (TSM) flow stands for the calibration of flow instruments, in particular the uncertainty analysis for calibration of Coriolis meters. This paper is an extension of the topic, discussing in depth the issues involved with ISO 17025 accreditation, maintaining calibrations, and traceability. The company has chosen to use Coriolis flowmeters as Global Reference Meters (GRM) to maintain the traceability on the TSM stands operating worldwide. To accomplish this ISO 17025 accreditation was successfully sought for the SSF Primary Flow Stand (PFS) that is used to calibrate the GRM’s. This paper will discuss the experiences associated with accrediting the SSF Primary Flow Stand, the processes involved with creating a GRM, calibrating TSM stands worldwide and the implications to TSM stand uncertainty .This paper includes: - Review of SSF Primary Flow Stand Uncertainty and Traceability - Internal Proficiency Testing Methodology - Practical experiences in attaining ISO 17025 accreditation - Process for GRM calibrations - Advantages to using the GRM process
Keywords:
Coriolis, traceability, ISO 17025, transfer standard, flow meter
