Restriction subs for setting cement plugs in wells,申请号US19880266266-传众专利搜索

Restriction subs for setting cement plugs in wells

申请公布号：US4907649(A)

申请号：US19880266266

申请日期：1988.10.26

申请公布日期：1990.03.13

申请人：

BODE, ROBERT E.

发明人：BODE, ROBERT E.

分类号：E21B33/16;E21B47/09

主分类号：E21B33/16

摘要：In accordance with illustrative embodiments of the present invention, restriction subs for use in setting cement plugs in wells include a tubular threaded adapter having an internal annular recess, and a metal restriction sleeve mount in such recess. In one embodiment, the sleeve has a corrugation that extends into the bore of the adapter to provide a deformable restriction; in another embodiment the sleeve has curved resilient tabs whose free ends extend into such bore. The restrictions are cooperable with a displacement plug having a metal expander member on its nose so that a distinct pressure is required to cause the expander member and plug to be forced through the restriction.