Gas flow uncertainties are the dominant factor in the energy equation and regular validations will minimise mis-measurements and un-accounted for gas.
		ISO 17025 accredited for on-site calibrations of temperature, pressure and differential pressure ensuring traceable validations with defined uncertainty.
		Financial confidence in billing of gas.
		We operate a re-calibration database and will remind clients of forthcoming instrument calibrations.

Metering system validation, if carried out correctly will reduce exposure to commercial risk created over time by possible over or under metering of total energy i.e. volume and heating value. There is a perception in many quarters that modern "fiscal standard" metering systems are "fit and forget" black box systems. This is most definitely not the case. Metering systems comprise of many separate measurement elements, all of which are susceptible to calibration drift and measurement bias over time. In addition, the flow computer system must be correctly set up and configured to use the correct constants and parameters from the outset and updated as appropriate.

EffecTech are independent gas metering specialists with a wealth of experience gained from across the globe. We specialise in performing comprehensive and regular traceable validations of the entire metering system. We typically work with large consumers of gas such as power stations and other energy intensive industries including gas transmission and LNG terminal operators.

In addition to metering validations we offer a troubleshooting and consultancy service to investigate and identify metering errors, lost or unaccounted for gas and suspected metering or energy imbalances across plant and hydrocarbon accounting chains.

We also to witness metering validations as an independent third party where the end user of the gas does not own and maintain the flow measuring equipment.

Auditing of metering system maintenance, preparation of metering validation procedures, training and mentoring and attending factory acceptance tests (FAT) as well as advice on metering system design and specification are other areas where we are able to assist clients.

Typically a metering validation will include performance evaluation of the following :

• Primary instrumentation

Orifice plates must be inspected, cleaned and regularly re-certified by an accredited metrology laboratory.

Ultrasonic flow meters can be "health checked" in situ by monitoring various operating parameters. They are also removed periodically and sent to an accredited calibration facility for re-calibration with high pressure natural gas.

Turbine meters should be monitored for "missing or bad" pulses. They are also removed periodically and sent to an accredited calibration facility for re-calibration with high pressure natural gas.

• Secondary instrumentation

Differential pressure (DP), pressure and temperature transmitters are calibrated according to our ISO 17025 calibration scope with certified, traceable UKAS test equipment ensuring a high standard of accuracy and traceability. DP transmitters often have a "footprint" calibration performed off site by other ISO 17025 accredited calibration facilities.

• Flow computer

Functions and calculations, e.g totalisation must be tested against independent off-line calculations to ensure they are correct. In addition, constants and system data such as orifice plate, pipe sizes and gas composition dependant factors entered into the flow computer must be verified.

• Gas analyser

Such as gas chromatographs must be checked and tested and the validity of the data they produce confirmed. EffecTech are world leaders in providing this service.