Two-pass method

{
  "id": "MLC-T-OAG-004485",
  "term": "Two-pass method",
  "field": "Oil and gas",
  "definition": "A production logging method in which a spinner flowmeter is logged on two passes, one moving up the well and one moving down. Reading the spinner response in both directions lets the tool's own velocity be separated from the fluid velocity. It needs fewer passes than the multipass method, which logs several line speeds in each direction to calibrate the spinner response fully.",
  "subject": "Production Logging",
  "url": "https://mlchart.com/terminology/oil-and-gas/two-pass-method/"
}