Accretion

{
  "id": "MLC-T-OAG-000022",
  "term": "Accretion",
  "field": "Oil and gas",
  "definition": "The buildup of sticky, partly hydrated cuttings and clay on the bit, drill collars, stabilizers, and other parts of the drill string, seen mainly when reactive shale is drilled with water-based mud. When it covers the bit it is called balling, and it reduces cutting action, annular clearance, and hole cleaning, and can lead to pack-off or stuck pipe. Lab tests measure it by rolling sized shale with a steel bar in the fluid and weighing the cuttings that stick to the bar.",
  "subject": "Drilling Fluids",
  "url": "https://mlchart.com/terminology/oil-and-gas/accretion/"
}