Research Reveals Inaccurate Meter Calibration is Costing the Oil & Gas Industry

New research from NEL, the custodian of the UK’s National Flow Measurements Standards, has revealed that the use of live fluids to test and calibrate multiphase flow meters increases measurement uncertainty by up to seven per cent. This inaccuracy could represent a potential financial mis-measurement of up to $36million per year for a well measured with a single multiphase meter.

While some favour the use of live fluids (i.e. natural gas, crude oil and brine), NEL’s laboratory research has proven they are less stable than substitute fluids (i.e. nitrogen, synthetic oils and synthetic brine), which deliver a more accurate result. It is for this reason that NEL has recently switched from using crude oil to refined oil as part of it multiphase flow loop meter testing.

Dr Norman Glen, Principal Consultant at NEL, said: “Proponents of live fluids argue that they are more representative of the conditions that the meter will encounter in service. However, our research has shown that due to the thermophysical properties of fluids, their use significantly increases uncertainty in calibration calculations. This means that inaccurate meters are being deployed in the field, potentially costing the industry and revenue authorities thousands of dollars every year.”

The use of substitute fluids, which provide a stable and well-characterised reference, is consistent with the approach recommended in the UK’s Department of Energy and Climate Change’s (DECC) Guidance Notes for Petroleum Measurement (Section 9.7), which makes specific mention of a preference for ‘model’ fluids to minimise additional uncertainties.