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:
Mar. 30, 2021
Filed:
May. 09, 2016
Applicant:
National Oilwell Varco, L.p., Houston, TX (US);
Inventors:
Assignee:
NATIONAL OILWELL VARCO, L.P., Houston, TX (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
E21B 7/02 (2006.01); E21B 15/00 (2006.01); B66F 11/04 (2006.01); E02D 7/16 (2006.01); E04H 12/34 (2006.01); E21B 15/04 (2006.01);
U.S. Cl.
CPC ...
E21B 7/02 (2013.01); E21B 15/003 (2013.01); B66F 11/042 (2013.01); E02D 7/16 (2013.01); E04H 12/345 (2013.01); E21B 15/04 (2013.01);
Abstract
A mast erection system includes a first mast erection apparatus that is adapted to pivotably raise a drilling rig mast of a drilling rig assembly to an intermediate raised position wherein the drilling rig mast is oriented at a first acute angle relative to a horizontal plane, and a second mast erection apparatus that is adapted to further pivotably raise the drilling rig mast from the intermediate raised position at the first acute angle to a fully raised position wherein the drilling rig mast is oriented at a second angle relative to the horizontal plane that is greater than the first acute angle.