Patent ID: 9506309
Filing Date: 2016-11-29
CPC Classification: E21B

Claim Text:
1. A downhole article comprising: a non-composite body configured to block a downhole conduit in an initial configuration, wherein the non-composite body is stable in a dry condition at ambient temperature, and, when exposed to a downhole fluid having a temperature of at least about 136° F., the non-composite body will change within about 48 hours to a subsequent configuration that does not block the downhole conduit and, in its changed configuration, is then capable of passing through the downhole conduit; wherein: the non-composite body is hard and prepared from high-molecular weight polyglycolic acid (PGA), namely Kuredux or its equivalent, which is suitable for high-pressure downhole fracking operations, has at least short-term term stability in ambient conditions, and will lose compression resistance and structural integrity due to hydrolysis in the downhole fluid in the wellbore; the non-composite body is spherical, and is in the range of between about 0.75 inches to about 4.625 inches in diameter; the non-composite body is homogenous; the non-composite body will degrade into glycerin and environmentally non-toxic substances within about one month of being exposed to the downhole fluid; and the downhole conduit is in a downhole tool useful for zonal isolation dimensioned on an outer side to engage casing in the wellbore and dimensioned on an inner side to engage the non-composite body, the downhole tool containing a structural element that will lose compression resistance and structural integrity due to degradation in the downhole fluid in the wellbore, causing the downhole tool to release from the casing without being drilled out and to thereafter degrade in the wellbore fluid into degradation products.