Thomas Alan Washburn

US Patent:

20110243774, Oct 6, 2011

Filed:

Mar 30, 2010

Appl. No.:

12/749828

Inventors:

Lance D. Underwood - Morrison CO, US
William D. Murray - Tomball TX, US
Thomas K. Washburn - Cypress TX, US

Assignee:

SMITH INTERNATIONAL, INC. - Houston TX

International Classification:

F01C 1/107
B23P 17/00
B21K 1/76
C25F 3/02

US Classification:

418 48, 29888, 72352, 205640

Abstract:

A Moineau style stator includes a stator tube having a plurality of rigid helical lobes formed on an inner surface thereof. The helical lobes define a major internal tube diameter that is greater than a pass through diameter of the tube such that the major diameter undercuts the pass through diameter of the tube. A major liner diameter may also be less than the pass through diameter so as to provide a suitable interference fit between rotor and stator.