US 7,120,543 B2 · Electronic gas flow measurement and recording device

Abstract

An electronic flow measurement device (EFM), for use in conjunction with a flow meter in a pressurized gas line, has a microprocessor and read-only memory (ROM), and calculates and records gas flow rates corrected for variable factors such as gas pressure, temperature, and density. Look-up tables stored in the ROM contain intermediate values calculated in accordance with selected protocols for selected ranges of input variables such as gas temperature, pressure, density, and turbine “K” factors. Based on inputs received from gas temperature and pressure sensors, the EFM selects corresponding intermediate values from the look-up tables, and then uses these values to calculate corrected gas flow rates, using software residing in the EFM. The microprocessor's power consumption is significantly reduced because the use of look-up tables reduces the complexity and extent of calculations that the EFM needs to perform, as compared with performing all required calculations in the EFM.

Claims19

Dependent claims

An electronic gas flow measurement device for use with an orifice meter mounted in a gas pipeline, said device comprising:

(a) a housing;
(b) a computer enclosed with the housing, and having a microprocessor and a read-only memory (ROM);
(c) data input means, for entering data in the ROM;
(d) data output means, for retrieving data stored in the ROM;
(e) means for receiving gas temperature inputs;
and
(f) means for receiving gas pressure inputs from upstream and downstream of the orifice plate of the orifice meter;
wherein:
(g) the ROM is adapted to store look-up tables of intermediate values for selected gas flow calculation parameters determined in accordance with one or more selected calculation method for selected ranges of gas temperature, density, and pressure differentials;
and
(h) the microprocessor is programmed with software for:
h.1 selecting intermediate values from the look-up tables corresponding to gas temperature and temperature inputs;
and
h.2 processing the selected intermediate values to calculate gas flow rates adjusted for temperature, pressure, and density, in accordance with one or more selected gas flow rate calculation methods.

11 more elements

Dependencies are inferred from the claim text.

Electronic gas flow measurement and recording device

Life of this patent

Electronic gas flow measurement and recording device

Life of this patent

Abstract

Claims19