Bit Balling Prevention & Treatment
About 60% of oil well footage is drilled in clays and shales. These rocks are neither hard nor abrasive and, thus, should be easy to drill. Problems arise, however, because of the soft and sticky nature of the cuttings produced. These cuttings absorb water from the drilling fluid, swell, and stick to the Drilling Bit. Balling occurs when clay-based drilled solids adhere together and cling to the metal surfaces of the bit and pipe.
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