Master Flow Meter for Precision Flow Meter Calibration & Proving

Fluidyne master flow meters use the patented and time-tested oscillating piston positive displacement technology to provide a high-accuracy reference for flow meter calibration, verification and master meter proving. With excellent repeatability of better than ±0.02%, each master meter ensures reliable volumetric measurement and provides an accurate and practical solution for laboratory and on-site master meter calibration.

High-precision Series 6600 ATEX transmitter for master flow meters calibration setup

Core Information

A master flow meter is a high-precision reference flowmeter characterized by exceptionally high repeatability, typically better than ±0.015%. Positive Displacement (PD) technology is particularly suited for master meter applications because it directly measures volumetric flow by repeatedly trapping and displacing precisely defined volumes of liquid within its measuring chamber.

Unlike Coriolis and turbine type flowmeters which are velocity-based, Positive Displacement meters do not require extensive flow conditioning, long straight pipe runs or a fully developed laminar flow profile, making them highly suitable for both laboratory and field flow meter calibration.

High repeatability is the foundation of master meter accuracy. Through multi-point calibration and linearization, a highly repeatable meter can achieve measurement accuracy of up to ±0.05%. Instead of applying a single K-factor across the entire operating range, Fluidyne master flow meters can be configured with up to 20 calibration factors. Fluidyne’s proprietary linearization algorithm enables the flow computer to determine the appropriate K-factor for the actual operating flow rate.

This combination of mechanical repeatability and digital linearization enables highly accurate and consistent master meter calibration and master meter proving across a wide operating range.

A Fluidyne Positive Displacement master meter consists of two critical elements

  • Precision metering assembly: Accurately machined metering body and rotors with dimensional tolerances maintained within 20 microns. For double case meters, the measurement chambers are pressure balanced to prevent distortion and eliminate drift in meter performance.

  • Advanced flow computer: Multiple K-factor configuration with Fluidyne’s proprietary linearization algorithm for high-accuracy flow measurement across the calibrated range.

  • Bi-Rotor Positive Displacement design for highly repeatable volumetric measurement
  • Accuracy up to ±0.05% for precision master meter applications
  • Repeatability better than 0.015% for dependable meter proving

  • Advanced proprietary linearization algorithms with upto 20 K Factors

  • Pressure-Balanced measurement chamber for stable measurement across operating conditions
  • Dual Pulse Quadrature Output for pulse verification, redundancy and flow direction detection
  • Gear-Tooth Pulse Sensing with no external rotating shaft, reducing maintenance
  • No Metal-to-Metal Contact between the primary metering elements
  • Low Pressure Loss across the meter
  • Wide Turndown Ratio for calibration across a broad flow range
  • Suitable for Mobile & In-Line Master Meter Proving
  • Suitable for Fuels, Oils, Hydrocarbons & Process Liquids
  • Robust Industrial Construction for laboratory and field calibration applications
  • Weights and Measures certified
  • OIML R117 – In progress
  • Direct calibration of test meters such as positive displacement, Coriolis, turbine
  • Reduced calibration costs
  • Portable calibration solution
  • Traceable flow calibration
  • Calibration of multiple flowmeters in series with master flowmeter

Applications

Industrial oil and gas pipeline installation using master flow meters for proving

Oil and Gas

  • Terminals
  • Fuel depots
  • Crude Oil
High-accuracy master flow meters utilized in aviation fuel calibration applications

Aviation

  • Aviation turbine fuel
  • Fuel terminals
Marine bunkering transfer system equipped with reference master flow meters

Bunkering

  • Petroleum products
  • Black Oils
Master flow meters installed in refined petroleum products metering skid

Refined products

  • Lubricants
  • Base oils

Related Products

Series 6600

High-precision Series 6600 ATEX transmitter for master flow meters calibration setup

  • Catalogue

  • Instruction Manual

FAQ’s

What are Master Flow Meters and where are they typically installed?

Master flow meters are high-accuracy reference instruments used to compare, verify and calibrate other flow meters. A master meter is typically installed in series with the meter under test, either permanently within a calibration system or temporarily for field verification. They are commonly used in calibration laboratories, metering skids, loading terminals, refineries, fuel depots and custody-transfer installations where reliable flow meter calibration is critical.

Master flow meters can employ positive displacement and Coriolis mass high-accuracy flow measurement technologies. The appropriate technology depends on the liquid, flow range, required accuracy and operating conditions. Positive displacement master meters are particularly suitable for liquid measurement because they directly measure discrete volumes and provide excellent repeatability. This makes them highly effective for master meter calibration and master meter proving across fuels, oils, hydrocarbons and process liquids.

Master flow meters allow operators to verify meter performance under actual operating conditions without routinely removing instruments for laboratory testing. They help identify meter drift, measurement errors and changes in performance while reducing downtime and calibration costs. On-site flow meter calibration and master meter proving are especially valuable where measurement errors directly affect product accounting, process control or custody transfer, providing a practical reference against which operating meters can be compared.

The master meter calibration interval depends on usage, required uncertainty, operating conditions, historical stability and applicable quality or regulatory requirements. Master flow meters used frequently or for critical custody-transfer duties may require more frequent verification than lightly used instruments. Calibration intervals should therefore be established from performance history rather than a universal schedule. Routine inspection, cleanliness checks and periodic traceable calibration help ensure the master meter remains a dependable reference for flow meter calibration.

When selecting master flow meters, consider accuracy, repeatability, measurement uncertainty, flow range, pressure rating, temperature, liquid compatibility and pressure loss. The master meter should provide significantly better measurement performance than the meters it will verify. Pulse resolution, calibration traceability, portability and installation requirements are also important. For master meter proving and field flow meter calibration, stable performance across the intended operating range is particularly important.