Patent · US Expired

Whipstock assembly and method of manufacture

US7353867B2 · kind B2 · utility

36Cited by
13References
40Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 14, 2003
Grant dateApr 8, 2008
Priority date
Expiry dateApr 14, 2023

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B7/061
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

The present invention discloses a whipstock assembly (100) for use in forming a lateral borehole from a parent wellbore. The whipstock assembly comprises a body (122) and a deflection member 120) above the body. The deflection member includes a concave portion (111) for deflecting a milling bit during a milling operation. Disposed on a perforation plate (110) portion of the concave portion is a raised surface feature (116). The raised surface supports a milling bit above the perforation plate portion during a milling operation. This, in turn, substantially prevents frictional contact between the milling bits and the perforation plate portion during a milling operation. The present invention also provides a novel method for manufacturing a whipstock in which a cavity portion is formed behind the perforation plate by milling out the backside of the deflection member and then joining a second back cover member to the whipstock body to complete the assembly.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.