INTERNALLY PROFILED STATOR TUBE

摘要

A thick walled Moineau-style stator (320) and method of manufacture are disclosed. The outer profile (355) of the stator follows the inner helical profile (353) of the stator. The application of an elastomeric layer (330) t o the inner profile of the stator results in a constant thickness for the elastomeric layer and proximity for the walls of the stator. This improves t he durability of the motor because of lower heat generation and better heat dissipation. The stator walls also support the elastomeric layer. Further, t he thick walls of the preferred stator eliminate the need for additional drill piping or other support provided adjacent the stator. Thus, the cost of additional piping and difficulties placing a stator inside drill pipe or dri ll string housing are eliminated. Further, the improved strength of thick wall steel when contrasted to a thin wall counterpart allows a higher operating pressure drop for a given stator length, resulting in a higher power output. Moreover, the undulating outer profile of the stator provides a distinctive appearance to the stator piping.