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How to Calculate Rate of Penetration

The rate of penetration is used by drillers, particularly in the petroleum industry, to state the rate at which a borehole is deepening while drilling progresses. Depending on the measurement system in use at the drill site, rate of penetration (ROP) is usually expressed in minutes per foot or feet per hour, or minutes per meter or meters per hour.

Things You'll Need

Driller's log
Calculator (optional)

Instructions

- 1
  Read Depth 1, measured depth at Time 1, and Depth 2, measured depth at Time 2, from the driller's log.
- 2
  Subtract Time 1 from Time 2 to obtain the time difference in hours. Convert to decimal hours by dividing the number of minutes by 60. For example, 2 hours 19 minutes = 2.317 hours.
- 3
  Subtract Depth 1 from Depth 2 to calculate the depth difference. For example, 2,040 feet -- 1,997 feet = 43 feet.
- 4
  Divide the depth difference by the time difference to obtain ROP in feet per hour. For example, 43 feet / 2.317 hours = 18.56 feet/hour.
- 5
  Convert the time difference to minutes. Multiply the number of hours by 60 and add the number of additional minutes. For example, 2 hours x 60 minutes/hour + 19 minutes = 139 minutes.
- 6
  Divide the time difference in minutes by the depth difference in feet to obtain ROP in minutes per foot. For example, 139 minutes / 43 feet = 3.23 minutes/foot.

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