Transitioned Damper Dimensions
When a fire/smoke damper is being used in conjunction with round or oval ductwork, the SMD-401M can be supplied in a
factory sleeve with round or oval transitions on both ends of the sleeve. Dampers should be ordered to the duct dimensions.
Drawings below show overall damper size.
* These dimensions are furnished approximately
1/4
in. (6mm) undersize, except round and oval dimensions which are
approximately
1/8
in. (3mm) undersize.
Ts = (2)(Sleeve Thickness)
Smoke Dampers meeting the following specifications
shall be furnished and installed where shown on plans
and/or as described in schedules. Dampers shall meet
the requirements of NFPA 90A, 92A, 92B, 101 and 105 and
further shall be tested, rated and labeled in accordance with
the latest edition of UL Standard 555S. Smoke dampers
shall be of low leakage design qualified to UL 555S Leakage
Class I.
Each damper /actuator combination shall have a UL555S
elevated temperature rating of 250°F (121ºC) minimum and
shall be rated to operate at maximum design airflow at its
installed location. Each damper shall be supplied with an
appropriate actuator installed by the damper manufacturer
at the time of damper fabrication. Damper actuator shall be
(specifier select one of the following) electric type for 24 volt
operation.
Damper blades shall be hollow extruded aluminum airfoil
type with structural reinforcing tube running full length of
each blade. Damper frame shall be galvanized steel formed
into a structural hat channel shape with reinforced corners.
Bearings shall be sintered bronze sleeve type rotating in
extruded holes in the damper frame. Blade edge seals
shall be silicone rubber designed to inflate and provide a
tighter seal against leakage as pressure on either side of
the damper increases. Jamb seals shall be stainless steel
compression type. Damper must be rated for mounting
vertically (with blades running horizontal) or horizontally and
be UL 555S rated for leakage and airflow in either direction
through the damper.
The basis of design is Greenheck Model SMD-401M.
Specifications
D* + 2 in. (51mm) +T s
D*
TYPE R
16 in. (406mm)
Min.
2
1
/
8
in.
D* + 2 in. (51mm)+T
s
TYPE O
W
*
H*
W*
+ 2 in. (51mm)+Ts
H* + 2 in. (51mm)+Ts
W*
H*
TYPE C
H* + 2 in. (51mm)+Ts
(54mm)
16 in. (406mm)
Min.
2
1
/
8
in.
(54mm)
16 in. (406mm)
Min.
W*+ 2 in. (51mm)+Ts
(54mm)
2
1
/
8
in.
Copyright ©
2007 Greenheck Fan Corporation
SMD-401M Rev. 5 April 2007
