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:
May. 14, 2013
Filed:
Apr. 21, 2010
Kevin J. Nikiforuk, Cypress, TX (US);
Dave C. Andrews, Bryan, TX (US);
Kevin J. Nikiforuk, Cypress, TX (US);
Dave C. Andrews, Bryan, TX (US);
Tesco Corporation, Houston, TX (US);
Abstract
A system for deploying a string of pipe from a drilling rig into a well includes a spider for mounting on a rig floor and a pipe gripper attached to the top drive. A hydraulic safety circuit monitors hydraulic fluid pressure at an apply port of the gripper and prevents hydraulic fluid pressure from being directed to move the slips to the released position if hydraulic fluid pressure is not already present at the apply port of the gripper. The safety circuit also monitors hydraulic fluid pressure at the apply port of the spider and prevents release hydraulic fluid pressure from being directed to move the gripping members to the released position if apply hydraulic fluid pressure is not already present at the apply port of the spider.