Problems such as stuck pipe, tight hole, washout, and sloughing can be related to shale stability. Tests used to determine if a specific shale is likely to cause problems include the capillary suction time (CST) test and the linear-swell meter (LSM) test. CST test results show the inhibitive effects of various slats and their concentrations on the dispersion of a shale.
- Capillary Suction Timer (CST) Model 440: The Model 440 Capillary Suction Timer (CST) consists of a digital timer, sample cell, and a specially selected filter paper composed of unidirectional fibers.
- Linear Swell Meter: Helps determine shale hydration or dehydration