Greenheck DFD Series Manual page 9

Approved Breakaway Connections
All breakaway connections described below may utilize the following duct sealants: PA2084T duct sealant adhesive
manufactured by Precision, DP1010 water base duct sealant manufactured by Design Polymerics, Grey Pookie,
Ductmate PROseal®, or CL Ward S Seal in accordance with SMACNA recommendations.
Transverse Joints
The transverse joints shown below are approved as breakaway connections.
• A maximum of two #10 (19 mm) sheet metal screws on each side and on the bottom may be used. The
screws should be located in the center of the slip pocket and penetrate both sides of the slip pocket.
• Dampers up to 20 inches (508 mm) high may use transverse joints on the top and bottom and Drive Slip
joints (see Figure 17) on the sides.
Plain "S" Slip Hemmed "S" Slip
Inside Slip Joint Standing "S"
Standing "S" (Alt.) Standing "S"
(Bar Reinforced)
Figure 16 - Transverse Joints
Round and Oval Duct Breakaway Connections
Factory furnished duct collars, type R and O, are also considered breakaway (see Figure 18).
Round or flat oval ducts connected to Type R or O damper collars shall be attached with #10 (19 mm) sheet metal
screws as follows:
• Ducts up to 22 in. (558 mm) wide (or dia.) and less shall have three screws.
• Ducts larger than 22 in. (558 mm) wide (or dia.) up to and including 36 in. (914 mm) wide (or dia.) shall have five
screws.
®
Double "S" Slip
Standing "S" (Alt.)
Standing "S"
(Angle Reinforced)
Duct
Type R and O
factory furnished
duct collars qualify
as breakaway
connections.
Duct
Type R, O
Figure 18: Type R and O Transition
Drive Slip Joint
Figure 17
r
Wall or Floo
Sleeve
Damper
Type B
r
Wall or Floo
Sleeve
Damper
Multi-Blade Fire and Combination Fire Smoke Dampers 9