Page 136 - Shale Shakers Drilling Fluid Systems

SHAKER USER'S GUIDE 119

of the actual "solids" discard. If the shaker is turned CONCLUSIONS
off, all of the flow across the shale shaker will be
discarded, as well as all of the drilled solids ar- Laboratory evaluation and comparison has the
riving at the shale shaker. Of course, it also dis- advantage of maintaining duplicate conditions
cards all the drilling fluid. This defeats the purpose between tests, but usually does not replicate field
of the separation. The quantity of drilled solids conditions. Caution must be exercised when ex-
discarded, as well as the quantity of drilling fluid, trapolating these results to field applications.
should be the criteria for evaluating shale shak- Field evaluation and comparison of two shale
ers. The quantity of low-gravity solids (drilled and shakers is extremely difficult. Any comparison
commercial), weighting agents (high-gravity, com- requires a methodical, invariant procedure that
mercial solids), and drilling fluid should be deter- validates the consistency of the conditions during
mined when testing shale shakers. the test.