capillary-suction-time test

1. n. [Drilling Fluids]
A type of static filtration test for water-base drilling fluid that measures the filtration rate (time for free water to pass between two electrodes) using filter paper as the medium. It is used primarily to indicate filter-cake permeability, but data from the test have been used to study how clays and shales react in filter cakes and how brines of various types affect clays in a filter cake.