Lower set insert for a downhole plug for use in a wellbore

Abstract

A flow back plug, a bridge plug, a ball drop plug and plug with a disintegratable check therein are made from a common subassembly including, in some embodiments, a mandrel, a slips/seal section, a setting assembly and a mule shoe. In other embodiments, the common components are a mandrel, a slips/seal section and a mule shoe. To make the flow back plug, a ball check is placed in the mule shoe. To make the bridge plug, an obstruction is inserted in the mule shoe. To make the ball drop plug, the mule shoe is left unobstructed so any ball dropped in a well seats in a tapered inlet to the mandrel. To make a plug with a disintegratable check, a ball dropped in the well is of a type that disintegrated in frac liquids. The setting assembly includes a setting rod connected to a setting device in the mandrel passage. When the plug is expanded into sealing engagement with a production string, the setting rod pulls out of the setting device leaving a passage through the mandrel and through the setting device. Another embodiment is an improved adapter sleeve used on conventional setting tools.

CLAIM 
     
       The ornamental design for a lower set insert for a downhole plug for use in a wellbore, as shown.