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Windsor Office
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  • Windsor, Colorado

  • United States

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  • Manhattan Hall,

  • Copious Melbourne, New Yourk

  • 08:00 - 16:30

  • Monday to Saturday

  • +1(123) 456 567

  • support@copious.com

  • Manhattan Hall,

  • Copious Melbourne, New Yourk

  • 08:00AM - 05:00PM

  • Monday to Saturday

Geometry Error and Contamination

Prognosis was installed on a 4”, sch 40, 0.4 beta orifice plate union meter in a Natural Gas Station. The operator was confident the meter was operating correctly. Prognosis immediately indicated that the meter had a significant problem. The Prognosis orifice meter pattern recognition malfunction shortlist included the wrong keypad entry of meter geometry. They checked their paperwork and discovered that the keypad entered orifice bore diameter of 44.5mm (i.e., 0.44 beta) was for the previous orifice plate, which had since been physically switched to a plate with a bore of 38.1mm (i.e., 0.38 beta). This induces a +37% flow prediction bias. The keypad entered geometry was correct. The Prognosis result changed, but a problem was still indicated.

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The resulting Prognosis orifice meter pattern recognition malfunction shortlist included a contaminated meter run. A skeptical meter user opened the meter to check. The photograph shows the corroded and consequentially contaminated meter run. Various published research implies a negative bias of 1 to 2% is typical in such cases. With an approximate flow of 106,000 m3/day such unidentified contamination induced bias of say -1.5% is:

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after 1 day $461
after 30 days $13,833
after 1 year $168,417

*based on gas price of $ 0.29/Sm3.