Patent ID: 7360612
Filing Date: 2008-04-22
Classification: E21B

Abstract:
1. A roller cone drill bit comprising: a bit body having a first support arm, a second support arm, and a third support arm extending therefrom; each support arm having a spindle extending therefrom; a respective bearing structure associated with each spindle; a respective cone assembly rotatably mounted on the bearing structure of each spindle for engagement with a subterranean formation to form a wellbore; a respective cutting structure associated with each cone assembly; each cone assembly having a respective axis of rotation corresponding generally with a longitudinal axis of each respective spindle; each cone assembly having a minimal moment center located proximate each respective axis of rotation; the minimal moment center of each respective cone assembly defined in part by each respective cutting structure; and each respective bearing structure having a center point located proximate the minimal moment center of the associated cone assembly.