Meter Provers

Verification and/or checking the accuracy of liquid meters can be done with a device known as a liquid displacement meter prover. Meter provers can be stationary or mobile. They can be bi-directional, unidirectional, piston type and small volume type. Meter provers are automated systems used to provide on-site calibration to verify flow meter uncertainty and establish the K-factor of a meter.

Provers are designed in accordance to the space available and the type of product to be proved, however, they must all be sized to accommodate the flow rates of the meters to be proved.

EN-FAB meter provers are in accordance with, and will meet the standards set forth by the American Petroleum Institute (API) and the International Organization for Standardization (ISO).

The petroleum industry and American Petroleum Institute (API) have accepted the use of volume displacement provers in two categories. The conventional pipe prover is a displacement prover with sufficient reference volume to accumulate 10,000 whole pulses in a single pass; and the captive displacement or small volume prover (SVP) is a displacement prover with insufficient reference volume to accumulate 10,000 pulses in a single pass and uses pulse interpolation software). In both cases, it will require multiply passes for a proving and to establish as new meter factor.

The conventional provers have been utilized for meter proving since the early 1950’s and the captive displacement prover entered the market in the mid 1970’s after the acceptance of the double chronometry or pulse interpolation (techniques which whole meter is counted between detector switch one and detector switch two and any remaining fraction of a pulse in calculated) as identified in API MPMS Chapter 4.6.