Pilot mill

{
  "id": "MLC-T-OAG-002791",
  "term": "Pilot mill",
  "field": "Oil and gas",
  "definition": "A downhole cutting tool with a smaller-diameter, protruding guide section at its tip, designed to enter and stabilize the mill within a tubular restriction before the main cutting structure engages. The pilot guides the tool, preventing it from straying and damaging the surrounding casing or liner while milling objects like bridge plugs or collapsed pipe. Pilot mills are classified by the shape of their cutting face, such as flat-bottom, concave, or convex, to match the object being milled.",
  "subject": "Well Workover and Intervention",
  "url": "https://mlchart.com/terminology/oil-and-gas/pilot-mill/"
}