MAJOR FACTORS AFFECTING DRILLING PENETRATION RATES (ROP)
The Drilling Penetration Rate (ROP)
In the drilling industry, the rate of penetration (ROP), also known as penetration rate or drill rate, is the speed at which a drill bit breaks the rock under it to deepen the borehole. It is normally measured in feet per minute or meters per hour.

Generally, ROP increases in fast drilling formation such as sandstone (positive drill break) and decreases in slow drilling formations such as shale (reverse break).
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