Restriction plug element and method

Abstract

A restriction plug element and method for positioning plugs to isolate fracture zones in a horizontal, vertical, or deviated wellbore is disclosed. The restriction plug element includes a partial hollow passage with an interior end. The partial passage enables the plug element to seat in a restriction sleeve member during treatment and subsequently degrade to form a complete hollow passage. The complete flow channel dissolves or degrades not only the outside but also the inside of the wall of the restriction plug element. Initially the flow is restricted by the closed end in the partial hollow passage and over time the flow channel opens up by degradation and allows fluid to pass through in either direction. During back flow in the well new fluid is circulated into the well and the restriction plug element continues to degrade.

Dependencies are inferred from the claim text.