Top inlet baghouse construction

In a baghouse dust collector for top inlet operation, including an upper horizontal tubesheet with a plurality of openings for entry of dust-laden gases into pervious filter bags associated with the openings and arranged in groups or gangs, and hopper means below the lower ends of the filter bags for collecting dust, the improvement comprising,

• an inflow thimble for each filter bag, including a generally bell-mouthed opening at an upper end, free of sharp breaks or angles, for smooth inflow of gases, with a large-radius outwardly-flaring peripheral flange larger in diameter than the tubesheet opening associated with the filter bag, for support by the tubesheet with the thimble extending down through the opening,
• gasket means for substantially sealing the thimble with the tubesheet against leakage of unfiltered gases,
• top end connection means associated with a filter bag and with the thimble for releasably securing the filter bag by its top end to the thimble, with the bag positioned over the exterior of the lower end of the thimble,
• a gas inflow plenum above the upper tubesheet having sufficient depth to provide headroom for an operator,
• a lower tubesheet with openings corresponding to and below the upper tubesheet openings, the lower openings leading to the hopper means,
• the tubesheet openings of both the upper tubesheet and the lower tubesheet being spaced apart sufficiently for a person to walk on the lower tubesheet between groups of the filter bags and to have access to the bottom ends of the filter bags,
• bottom end connection means associated with the lower tubesheet for releasably connecting the bottom end of the filter bag to the lower tubesheet at an opening, by operations conducted entirely above the lower tubesheet, and including bottom end sealing means for substantially sealing against leakage of unfiltered gases, and
• tensioning means for applying tension to each filter bag at its lower end, from a position above the lower tubesheet,
• whereby, once the upper end of a filter bag has been connected via the thimble to the upper tubesheet, an operator may go onto the lower tubesheet and connect the bottom end of the filter bag via the bottom end connection means to the lower tubesheet.