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. 25, 1976
Filed:
Feb. 06, 1974
Richard E Wells, Westminster, CA (US);
Victor E Derval, Seal Beach, CA (US);
John D Muchow, Cerritos, CA (US);
Willis Oil Tool Co., Long Beach, CA (US);
Abstract
Pressurized fluid is controlled by a reverse valve gate on a valve stem that extends through annular packing in a bore of a bonnet to a piston in an outer control chamber. Control fluid pressure moves the piston inward to open the valve against line pressure on the valve and/or spring pressure on the valve. In the absence of both line pressure and control pressure, the valve is closed by spring pressure. The control chamber construction permits quick replacement of control chamber seals. In the event of a fire, the control chamber seals disintegrate to release the control pressure and thus cause line pressure and/or spring pressure to close the valve. The valve stem packing may be conveniently expelled hydraulically for replacement. Various different control assemblies may be mounted interchangeably on the valve bonnet without disturbing the structure of the valve. An auxiliary control may be quickly mounted on the outer end of the control chamber to convert the shut-off valve to manual operation.