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:
Jul. 17, 2018
Filed:
Aug. 01, 2014
National Oilwell Varco, L.p., Houston, TX (US);
Timothy S. Steffenhagen, Fort Worth, TX (US);
William B. White, Bedford, TX (US);
National Oilwell Varco, L.P., Houston, TX (US);
Abstract
When one of at least two independently driven gripper chains () of a coiled tubing injector () begins to turn faster than another one of the injector's other independently drive gripper chains by an amount that indicates slipping of one of the independently driven gripper chains relative to tubing () being held between the driven gripper chains, a hydraulic timing circuit (), which is coupled with the driven chains through hydraulic timing motors (), generates a pressure signal that causes the injector's hydraulic traction system to increase the hydraulic pressure applied by hydraulic cylinders () to generate a normal force applied by grippers on the chains to the tubing.