Gas dilutor and flow device calibrations
Calibration of gas dilutors and flow control and measurement devices is a cost-effective way of confirming accurate operation. Calibrations are carried out using gravimetrically measured flow rates, traceable reference flow meters and NPL’s suite of high accuracy dilution facilities. These include NPL's high accuracy gas flow dilutor (based on an internally calibrated network of critical flow orifices) and Molbloc dilution facility.
High accuracy gas flow dilutor. Valves A to F are switched to flow standard or diluent gas.
An intermediate position on each valve closes the gas supply.
Gas dilutor and divider calibrations
NPL provides dilutor and divider calibrations for an ideal gas, using mixtures containing low amount fractions of carbon monoxide in a nitrogen matrix. Gas correction factors may be required when using the dilutor at higher amount fractions or with other compounds. Calibrations can be performed with bespoke compounds and amount fractions to remove measurement uncertainty introduced from using gas correction factors.
Flow control and measurement device calibrations
NPL provides calibration of flow control and measurement devices for a range of gases including nitrogen, air, argon, methane, carbon dioxide, hydrogen and helium. Calibration set points can be specified (between 1 – 5000 ml/min) to meet requirements.
Calibrated instrumentation is returned with an NPL test report providing the calibrated set points with an uncertainty statement. A relative expanded uncertainty of ± 0.5% is offered which can be altered to meet requirements.
Contact
Customer Service tel: +44 20 8943 8637
E-mail: gases_enquiries@npl.co.uk