Damper Selection And Sizing - Honeywell AUTOMATIC CONTROL Engineering Manual

LINKAGE
ARM
LINKAGE
ROD
LINKAGE ARM
TORQUE APPLIED TO DAMPER = 5 LB-IN. PER FT 2 OF DAMPER AREA
3.0
2.0
1.0
0
0 10 20 30 40
LEAKAGE IN CFM PER FT 2 OF DAMPER AREA (FT 3 /MIN)
NOTE:
LEAKAGE OF A SPECIFIC DAMPER DEPENDS UPON THE HEIGHT AND
WIDTH RELATIONSHIP AS WELL AS THE AREA. THE SHADED AREA
SHOWS THE RANGE OF LEAKAGE FOR A GIVEN AREA.
Fig. 18. Graphic Presentation of Leakage Performance.
DUAL
LINKAGE ARM
AXLE SCREWS
Fig. 17. Typical (Opposed Blade) Damper Construction.
50 60 70 80 90
C2391

DAMPER SELECTION AND SIZING

TRUNION
BEARING
HORIZONTAL
FRAME MEMBER
DAMPER BLADE
SIDE
SEAL
BLADE
AXLE
DRIVE
AXLE
THRUST
WASHER
AXLE BEARING
VERTICAL
FRAME MEMBER
110
LEAKAGE VS DAMPER SIZE
100 APPLIED TORQUE 50 LB-IN.
ACTUAL TEST DATA
90
80
70
60
50
40
30
20
10
0
0 6 12 18
A DIMENSION
DAMPER SIZE IN INCHES
TOTAL LEAKAGE =
B-DIMENSION LEAKAGE + A-DIMENSION LEAKAGE
WHERE:
A-DIMENSION = OUTSIDE DIMENSION PARALLEL TO
THE DAMPER BLADES
B-DIMENSION = OUTSIDE DIMENSION PERPENDICULAR
TO THE DAMPER BLADES
Fig. 19. Low Leakage Dampers.
459 ENGINEERING MANUAL OF AUTOMATIC CONTROL
M10436
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
24 30 36 42 48
B DIMENSION
M10419