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. 11, 1993
Filed:
Sep. 13, 1991
Applicant:
Inventor:
Graham Clydesdale, Aberdeen, GB;
Assignee:
Diamant Boart Stratabit Limited, Aberdeen, GB;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21B / ;
U.S. Cl.
CPC ...
175244 ; 166325 ; 175239 ;
Abstract
A system is described which enables the safe release of formation gases when corebarrel is being raised. A corebarrel has an elongate cylindrical outer casing (1) and an elongate cylindrical liner (2), the liner (2) being disposed within the outer casing (1) such that there is a space (3) between the liner and the outer casing. The liner (2) has a plurality of unidirectional valves (4) which enable the passage of gas from the volume (5) within the liner (2) to the space (3) between the liner and outer casing, and prevent the passage of fluids from the space (3) to the volume (5).