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. 16, 1990
Filed:
Feb. 01, 1989
Thomas F Bailey, Houston, TX (US);
Raymond A Todd, Jr, Houston, TX (US);
Drilex Systems, Inc., Houston, TX (US);
Abstract
A mud saver valve for insertion within the drill string to retain mud in the drill pipe and prevent the mud column from flowing past the valve when pumping is interrupted. The valve body has a tubular body and a piston having an axial passage for the flow of drilling mud. This piston is biased within the body by a spring and axially movable in response to the mud flow. A check valve plug is disposed within the bore which may be removed to run wireline tools. The plug is seated within a reduced diameter portion of the body and includes a replaceable inner sleeve which engages the piston to prevent flow through the valve. The inner sleeve is replaced as it becomes worn due to the erosive forces of the drilling mud.