Measuring the Principle of Natural Gas Differential Pressure Flow Meter System

Natural Gas Orifice Flow Meter For measuring gas, differential pressure flow meter is the most widely used type of flow meter, and its usage ranks first among all types of flow meters. In recent years, due to the advent of various new flow meters, its usage percentage has gradually decreased, but it is still the most important type of flow meter. The differential pressure flow meter is an instrument that calculates the flow rate based on the differential pressure generated by the standard orifice plate installed in the pipeline, the known fluid conditions and the geometric dimensions of the standard orifice plate and the pipeline. The differential pressure flow meter consists of a primary device (standard orifice flow meter) and a secondary device (differential pressure transmitter, distributor, controller and flow computer). The

orifice flow metering system is mainly composed of a standard orifice plate, a differential pressure transmitter and a flow computer, that is, it consists of two parts: hardware and software. The main function of the orifice flowmeter is to generate pressure differences P1 and P2 on the upstream and downstream sides when the gas flows through the orifice; the function of the differential pressure transmitter is to convert the pressure difference into a standard signal of 4-20mA; the flow computer is mainly programmed and configured based on the SY/T6143-2004 standard - "Measuring natural gas flow with standard orifice flowmeter", with the practical formula qvn=AvnCEd2FGεF2FT (P1△P) for calculating the volume flow of natural gas under standard conditions as the core, and all the collected relevant natural gas working condition data are processed, and finally displayed to the user as the standard volume flow. (end)