AUTOMATED POSITIVE DISPLACEMENT METHODS IMPROVE PRIMARY STANDARDS FOR GAS FLOW CALIBRATION

摘要

The gas flow calibration methods with the highest accuracy potential are those based on the positive displacement principle. Because the positive displacement method of flow calibration is based on standard measurements of length and time, it is considered a primary standard by the National Institute of Standards and Technology. Two common positive displacement tools used for gas flow calibration are bell provers and piston meters. Automating these devices vastly improves measurement accuracy, simplifies operation and facilitates ISO documentation practices.