A seismic flexible connection for positively pressurized sheet metal ductwork allows for structural deflection up to thirty inches in any horizontal direction. A thirty-six-inch wide flexible connector material is sandwiched between an outer one-and-a-half by one-and-a-half by one-eighth-inch steel angle and the duct wall to cover frayed ends and provide a penetration area for fasteners. Half-inch bolts and washers secure the assembly at twelve inches on center all around, with sealant applied at contact areas and bolt holes to maintain an air-tight seal. Appropriate release clips hold the fabric out of the airstream during normal operation while allowing it to deploy during seismic activity. A twelve-inch gap accommodates the extended connector position in supply ducts.
NOTES: (1) PROVIDE APPROPRIATE CLIPS TO HOLD FLEXIBLE CONNECTION OUT OF AIR STREAM AND TO PREVENT IT FROM BALOONING OUT. CLIPS SHALL BE ABLE TO RELEASE CONNECTOR FABRIC DURING SEISMIC ACTIVITY SO THAT DUCTS ARE ABLE TO DEFLECT AS REQUIRED (30 INCHES ANY HORIZONTAL DIRECTION). (2) SANDWICH 1" OF FLEXIBLE CONNECTOR BETWEEN OUTER ANGLE & DUCT TO COVER ANY FRAYED ENDS & TO PROVIDE AREA FOR BOLTS TO PENETRATE MATERIAL. APPLY APPROPRIATE SEALANT ON CONTACT AREAS & AT BOLT HOLES TO SEAL SYSTEM AIR TIGHT. (3) CONNECTION SHALL BE USED FOR POSITIVELY PRESSURIZED DUCTWORK SYSTEMS ONLY. (4) FLEXIBLE CONNECTION MATERIAL SHALL BE AS SPECIFIED FOR "DUCT FLEXIBLE CONNECTIONS" IN SECTION 23 3314. (5) PROVIDE DUCT SEISMIC CONNECTOR WHERE REQUIRED BY THE CONTRACTOR'S STRUCTURAL ENGINEER. PROVIDE 36" WIDE x DUCT PERIMETER LENGTH FLEXIBLE CONNECTION - SEE SPECIFICATION FOR MATERIAL TYPE. FLEXIBLE CONNECTOR IS SHOWN IN EXTENDED POSITION AS IT WILL APPEAR IN SUPPLY DUCT AFTER HOLDING CLIPS RELEASE. SEE NOTE (1). 12" GAP FLEXIBLE CONNECTOR 1/2" BOLT & WASHER 12" OC 1-1/2"x1-1/2"x1/8" ANGLE ALL AROUND, TYP. BOTH SIDES TACK ANGLE, NUT, AND WASHER TO INSIDE OF DUCT AFTER DRILLING BOLT HOLES SHEET METAL DUCT
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