Abstract: A method that includes pulling a sled disposed on a trough across a first filtercake at a constant speed, measuring a force versus distance or time based on the pulling; and outputting a frictional force curve is described. An apparatus that includes a base, a pulley attached to the base, a trough attached to the base, a sled disposed on the trough, a cable connecting the pulley and the sled, the cable connected to an arm capable of being moved at a constant speed, and a system to measure the force required to move the sled is also described.

Abstract: A method for using a drilling fluid test device including a test cell including a perforated plate disposed proximate a first end of the test cell, a piston disposed within the cell, a first chamber formed between the perforated plate and the piston, the first chamber configured to receive lost circulation material (LCM), a second chamber formed between the piston and a second end of the test cell, the piston providing a seal between the first and second chambers, a fluid inlet disposed proximate the second end of the test cell configured to introduce fluid into a second chamber of the test cell, a filtrate outlet disposed proximate the first end of the test cell to discharge filtrate, and a pump in communication with the fluid inlet.