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:
Oct. 02, 2001
Filed:
Jan. 02, 2001
Edmund A. Fisher, Houston, TX (US);
Cooper Cameron Corporation, Houston, TX (US);
Abstract
An apparatus for rapid venting of the compressed air and deballasting of a buoyant air tank in a positively buoyant riser system in the event of a premature drive off or a riser section parting is shown. The rapid venting of the compressed air ensures that the riser section cannot rapidly ascend to the surface and damage the drilling rig positioned above. In a first embodiment, the buoyancy tank or housing includes a circumferentially shaped channel positioned on its upper end. An annularly shaped ring is placed over the circumferentially shaped channel and sealed in place by a frangible weld. A tether line attaches to the annularly shaped ring and extends to an anchor point on the BOP stack below. In the event of a catastrophic parting of the riser, as the riser sections and attached buoyancy tank or housings begin ascending, the tether line is drawn tight. Further ascension of the buoyancy tank or housings, causes the frangible weld joints to break and peel back the annularly shaped ring, exposing the circumferentially shaped channel. This causes an immediate and complete venting of the buoyancy tank or housings, rendering them negatively buoyant. Alternate embodiments using an annularly shaped flange releasable by toggle clamps or retainer pins are also shown.