Drop sub

{
  "id": "MLC-T-OAG-004302",
  "term": "Drop sub",
  "field": "Oil and gas",
  "definition": "A mechanical device in a downhole tool string, particularly in tubing-conveyed perforating, that allows a section of the assembly below it to be released and dropped to the bottom of the well. Releasing the spent guns and other components clears the tubing bore for subsequent production or intervention operations. The release mechanism is activated by applying pressure, dropping a bar, or using an electric signal, depending on the specific design of the sub.",
  "subject": "Perforating",
  "url": "https://mlchart.com/terminology/oil-and-gas/drop-sub/"
}