The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 08, 1995
Filed:
Mar. 31, 1994
Applicant:
Inventors:
Bill D Andrew, Tulsa, OK (US);
William D Duwe, Broken Arrow, OK (US);
Michael L Wilson, Tulsa, OK (US);
Assignee:
TDW Delaware, Inc., Wilmington, DE (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B23B / ;
U.S. Cl.
CPC ...
408-8 ; 408101 ;
Abstract
An apparatus for tapping an opening into an existing pipeline that is under internal pressure including an elongated tapping machine body having means on one end for attachment to a pipeline, a boring bar having a rotatable feed screw therein by which the boring bar is axially positioned, and a pressure responsive valve actuated by differential pressure between the interior of a pipeline and the interior of the tapping machine body to control hydraulic pressure inside the tapping machine body to thereby counterbalance the hydraulic force applied to the boring bar.