The preponderance of evidence shows that completion effectiveness, and especially well productivity, is directly related to the use of clean completion and workover fluids.

Even small amounts of solids (500 ppm) in completion and workover fluids can be enough to bridge in perforation tunnels, in channels behind pipe, and in gravel packs and in propped fractures. This plugging is responsible for many wells producing at 1085% of full potential; for multiple squeeze attempts so often necessary to successfully seal cement channels; and for sticking pipe during concentric tubing operations.

It is a widely held myth among industry operations personnel that plugg ng material is easily removed with reactive materials such as HF acid in the case of clay solids or HCl acid in the case of carbonate solids.

Tests and field experience indicate that significant increases in flow conductivity are obtained not only with clean fluids instead of muds and dirty fluids, but also when larger pressure differentials into the wellbore exist while perforating.

You can access this article if you purchase or spend a download.