A combination of a casing tube and a closed end unthreaded tubular thread protector that has an inside diameter significantly greater than the outside diameter of the casing tube is described. Further, the thread protector is typically much longer than the threaded portion of the associated casing tube such that a significant amount of axial movement of the protector relative to the casing tube is required to remove it therefrom. The casing protector is most typically comprised of a polymeric material, such as polyethylene or polypropylene, that is soft enough as to not damage or mar the threads on the casing in which it is in contact, but stiff enough in the tubular form of the protector to prevent impact loads from being transferred to the threads there beneath.