Greenheck DFD Series Installation, Operation And Maintenance Manual page 26

Approved Breakaway Connections....
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 (19mm) sheet metal
screws as follows:
• Ducts up to 22 in. (558mm) wide (or dia.) and less
shall have three screws.
• Ducts larger than 22 in. (558mm) wide (or dia.) up
to and including 36 in. (914mm) wide (or dia.) shall
have five screws.
Manufactured Flanged System Breakaway Connections
Flanged connection systems manufactured by Ductmate, Durodyne, Ward, Nexus, Radiant T-35m, and MEZ are
approved as breakaway connections when installed as illustrated (see Figure 19).
Proprietary Flange System Breakaway Connections
(TDC by Lockformer, TDF by Engle)
TDC and TDF systems are approved as breakaway connections when installed as described in the TDC or TDF
addendum to the SMACNA Duct Construction Standards. Standard 6 in. (152mm) metal clip may be used with
spacing as shown in diagram (see Figure 20 & 21). 3
together corner pieces (see Figure 22).
Sleeve
Duct
Sleeve
Duct
Typical TDC/TDF joint
Figure 20
Typical TDC/TDF joint
10 Multi-Blade Fire and Combination Fire Smoke Dampers
6 in. long metal cleat or 1/16 in.
max. thickness plastic cleat;
12 in. c-c (min. 1 per side)
Flanged system angles
(Attach per
manufacturer's
instructions)
Duct
Figure 19
Clip Spacing
Std. Clip
Length
Clip Spacing
Std. Clip
Length
9 in.
6 in. 6 in.
6 in. 6 in.
60 in. Duct
60 in. Duct
4 Req'd.
4 Req'd.
7 in.
7 in.
48 in. Duct
48 in. Duct
3 Req'd.
3 Req'd.
5 in.
5 in.
36 in. Duct
3 Req'd.
36 in. Duct
5 in.
3 Req'd.
5 in.
24 in. Duct
2 Req'd.
24 in. Duct
2 Req'd.
18 in. Duct &
Smaller
C L
1 Req'd.
Duct
18 in. Duct &
Smaller
1 Req'd.
Figure 21
Type R and O
factory furnished
duct collars qualify
as breakaway
connections.
Figure 18: Type R and O Transition
Fire Damper Sleeve
3/8 in. bolts in
corners are optional
Neoprene or Butyl gasket
between all angles
⁄ in. (9.5mm) metal bolts and nuts may be used to fasten
3
8
9 in.
6 in.
6 in.
7 in.
7 in.
5 in.
5 in.
5 in.
5 in.
C L
Duct
Duct
Damper
Type B
Wall or Floo
Duct
Damper
Type R, O
Duct End
Flange
Corner Piece
Figure 22
r
Sleeve
3/8 in. bolt
(optional)