Meter

Written by Jerry Ratzlaff on . Posted in Flow Instrument

A metering device provides a measurement for the flow change in a gas or liquid.

A flowmeter is specified as FM on instrument bubbles on piping and instrumentation diagram (P&ID).

types of metering systems

Metering System

Metering systems can be simple or complex, a single piece of equipment or a skid.  A single piece of equipment would be something that fit between two pieces of pipe like a venturi tubes or flow nozzles.  A metering skid is a fabricated frame where equipment is installed on such as a meter run, transmitters, control valves and control panels.  The skid can be self contained, part of a system, portable or stationary.  Metering systems can be split into three types: gas, liquid or LNG.

Gas Metering System

Gas metering can be a single or multi stream.  Different gas metering technologies have different benefits, such as Coriolis Meters, Orifice Meters, Turbine Meters, Ultrasonic Meters and Venturi Meters.

Liquid Metering System

Different metering requirements require different applications, such as Coriolis Meters, PD Meters, Turbine Meters and Ultrasonic Meters.

LNG Metering System

LNG metering is for custody transfer.  Cooling natural gas to approximately -162°C (1/600th of its volume) it condenses to a liquefied state. Other words it changes from a gas to a liquid.  Without this change it would make transporting the gas more expensive.

abbreviations

  • FM - flowmeter
  • LNG - Liquefied Natural Gas
  • M - meter

standards

  • ISO Standards
    • ISO 2425 - Hydrometry -- Measurement of liquid flow in open channels under tidal conditions
    • ISO 2714 - Liquid hydrocarbons -- Volumetric measurement by displacement meter systems other than dispensing pumps
    • ISO 2715 - Liquid hydrocarbons -- Volumetric measurement by turbine meter systems
    • ISO 5167-1 - Measurement of fluid flow by means of pressure differential devices inserted in circular cross-section conduits running full -- Part 1: General principles and requirements
    • ISO 5167-2 - Measurement of fluid flow by means of pressure differential devices inserted in circular cross-section conduits running full -- Part 2: Orifice plates
    • ISO 12242 - Measurement of fluid flow in closed conduits -- Ultrasonic transit-time meters for liquid