B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
B01D—SEPARATION
B01D35/00—Filtering devices having features not specifically covered by groups B01D24/00 - B01D33/00, or for applications not specifically covered by groups B01D24/00 - B01D33/00; Auxiliary devices for filtration; Filter housing constructions
B01D35/02—Filters adapted for location in special places, e.g. pipe-lines, pumps, stop-cocks