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:
Mar. 28, 1989
Filed:
Dec. 23, 1986
Richard E Swint, Littleton, CO (US);
Robert J Newman, Englewood, CO (US);
Total Engineering and Research Company, Denver, CO (US);
Abstract
A process is disclosed for controlling movement of a vertically movable plug valve with respect to a bottom open end of a riser conduit of a catalytic conversion apparatus during startup and shutdown. The method involves sensing the pressure between the communicating surfaces of the plug valve and the riser conduit as the riser conduit expands or contracts due to thermal changes experienced during startup and shutdown. When the riser conduit expands and causes the pressure to exceed a preselected range, the position of the plug valve with respect to the riser conduit is lowered to reduce the pressure to within the range. When the riser conduit contracts and causes the pressure to fall below the preselected range, the position of the plug valve with respect to the riser conduit is raised to prevent catalyst flow through the valve.