Downhole tools having non-toxic degradable elements and methods of using the same

摘要

Downhole tools for use in oil and gas production which degrade into non-toxic materials, a method of making them and methods of using them. A frac ball and a bridge plug comprised of polyglycolic acid which can be used in fracking a well and then left in the well bore to predictably, quickly, and safely disintegrate into environmentally friendly products without needing to be milled out or retrieved.

主权项

1. A downhole tool for engaging a wellbore casing of a hydrocarbon well and temporarily isolating a zone in the wellbore above the tool from a zone in the wellbore below the tool, the downhole tool comprising:
structural elements including a cylindrical mandrel having an outer surface and an inner surface, the inner surface defining an inner conduit, and outer elements disposed on the outer surface of the mandrel, the outer elements comprising at least slips located and configured to have an initial run-in position and a final set position, the slips configured to engage the wellbore casing in the set position, and cones located and configured to drive the slips from the initial run-in position to the set position to set the downhole tool against the wellbore casing to isolate a zone in the wellbore above the tool from a zone in the wellbore below the tool; wherein at least some of the structural elements, at least the mandrel, comprise a hard high-molecular-weight polyglycolic acid non-composite degradable material, namely Kuredux grade 100R60 or its equivalent, that will degrade in a downhole fluid at fluid temperatures above about 150° F.; and the tool comprised to cease isolating the wellbore zone above the tool from the wellbore zone below the tool without drilling out the tool or other intervention from the surface within about two days of the tool being exposed to the downhole fluid in the wellbore due to loss of crystalline structure in the structural elements comprised of the degradable material causing mechanical failure of the tool.