US Patent 10016918 Flow resistant packing element system for composite plug

A downhole tool, such as a composite bridge plug, has a packing element disposed on a mandrel of the tool adjacent an activating element, such as a cone and slip arrangement. The packing element includes a packer and at least one backup ring. The packer is composed of packing material and is compressible on the downhole tool at least in part due to the activating element. The at least one backup ring limits extrusion of the packer. The at least one backup ring is molded into the packing material at one end of the packer adjacent the activating element. Preferably, each end of the packer has at least two backup rings molded therein, and slots in the adjacent backup rings are preferably offset at the ends.