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Production Logging Threshold Velocity
______________________________________________________________________ An actual cased‐hole log has been filed without interpretation during summer of 1983. Several years afterwards, the same well is showing a declining performance. An assessment history of the well past performance is needed to diagnose the current status from observations and possibly prepare remedial action. The essential data available from the old log are copied in the next pages. In 1983, CPI logs were not available. Make up for the backlog of data gathering. Browse through data and answer the following questions. Questions 1 – Is this well located onshore or offshore? 2 ‐ Is this well vertical or deviated? 3 – What is the status of this well? 4 – What are the depths MD of the perforated zones in this well? 5 – What is the total depth TMD of this well? 6 – What logs have been run? 7 – Would a Gradiomanometer add value to the information? 8 – Calibrate tool (use blank chart provided). 9 – Determine threshold velocity. 10 – Determine full downhole flowrate in 7" (17.8 cm) casing, if at all possible. 11 – Determine total flowrate and percentage flowrates per zone. 12 – As for an actual job, provide comments, conclusions and recommendations. Notes 1 – As seen on the left scale, the logging runs have been performed with depth being measured in meters, while the blank calibration chart bears tool velocity units in ft/min. 2 – Cross‐check the cable speed indications on the left track of logs. 3 – Whenever flowmeter scale is absent from the right track, assume it to be 0 – 40 RPS. 4 – Observe where the recordings have been made by comparing with well completion sketch.
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BAKER FAB retainer production packers are large bore packers designed for high flowrates. WEG : Wireline Entry Guide (Mule shoe)
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Logging in 4‐1/2 in. tubing
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Logging in 7 in. liner
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70
10
30
70
3
07
0
11
30
70
3
07
0
30
70
12
30
70
3
07
0
30
65
3
07
0
10 RPS
10 RPS
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