Infinite Dry-Running And Solids-Handling Via Combining Mag-Drive And Gas Seal Technology

This paper presents installation and field experience of the barrier sealless pump design. Barrier design is a combination of a sealless mag-drive design and gas seal technology. Gas seal separates the fluid end from the power end, thus allowing infinite dry running operation and solids-handling capability to 40 percent particulates. Since the back end is separated, fluid-lubricated journal bearings are not required, and antifriction ball bearings, are used instead—providing stiff rotor construction, with L3/D4 ratio as low as 9.3, which significantly minimizes deflections of the shaft. At the same time, a containment shell ensures leak-free operation and no spills, even in the unlikely event of barrier seal failure. Installation of the gas barrier design improved the mean time between failure for a tough application at a major chemical plant from six days to two years, and the pump continues to operate successfully. This paper, and the accompanying presentation, goes over details of the design, application, and installation experience by the pump manufacturer, a distributor, and plant engineering, operating, and maintenance personnel. 121 INFINITE DRY-RUNNING AND SOLIDS-HANDLING VIA COMBINING MAG-DRIVE AND GAS SEAL TECHNOLOGY