Contact time

{
  "id": "MLC-T-OAG-000825",
  "term": "Contact time",
  "field": "Oil and gas",
  "definition": "The duration that a fluid, such as a chemical wash or spacer, is in physical contact with a surface before being displaced by another fluid. In cementing operations, it is the calculated period that a preflush is pumped against the casing and formation to remove drilling mud residue and improve the cement bond. This time is a function of the pump rate and the annular volume being cleaned, and it is a specified parameter in the cementing program.",
  "subject": "Drilling Fluids",
  "url": "https://mlchart.com/terminology/oil-and-gas/contact-time/"
}