High Tech Expansion Joints Built for Netherlands

Refining FCC Upgrade

Key decision makers at the Netherlands Refining Co. (NEREFCO) believe that FCC expansion joints should be built with the most up to date features to insure long service life. The expansion joints furnished or a major upgrade to the NEREFCO Europort FCC facilities included the best technology Senior Flexonics Pathway has to offer for critical use expansion joints.

The design conditions of the expansion joints were 30 psig (2.07 BarG) at 1364 F (740 C). To avoid stress problems caused by differential growth between the pipe and the pressure thrust restraints, Senior Flexonics Pathway standard floating rings were used to anchor the hinges in place. The bellows covers were designed to contain the media pressure and be sealable in service in the event of a major bellows leak. The bellows were of the Senior Flexonics Pathway standard Ply Testable design with a patented Red Top leak detector system. This unique Senior Flexonics Pathway concept allows any bellows leakage to be detected and monitored without any risk to operations. The space between the internal liners and bellows elements was packed with ceramic insulation pillows to keep particulate out of the bellows and to reduce the operating temperature of the bellows below the creep range for the Alloy 625 bellows material. Senior Flexonics Pathway’s extreme duty liner seal was also used.

If an FCC service bellows element drops below the condensation point of any portion of the media stream in operation, that media stream will condense onto the bellows. Typically, acids of sulfur are the first liquids to condense out in FCC service as the temperature drops below 400OF (204 C). If this happens, the bellows can pit or generally corrode at a rapid rate. To isolate the bellows from weather effects and maintain the bellows temperature above the dew point of the media during operation, permanent external insulation was installed over the bellows elements.

As a final safety measure, Senior Flexonics Pathway installed three thermocouples on each bellows element to monitor the actual operating temperature of each bellows in service. Readings taken after startup indicated that the bellows were operating in a safe range of temperatures.