Milnor 6458, Installation Manual

Page: 57 / 93

Pellerin Milnor Corporation
Units of Measure (cont'd.)
Air velocity fpm feet per minute (npm)
meters per
minute
Pressure drop
iwc inches water
column (Pa) Pascals
3.2. Duct Components and Their Pressure Drops
BNDDUI01.R03 0000086877 A.10 A.11 Released
The table that follows, gives selected round and rectangular duct sizes for each dryer model, in
straight lengths and 90 degree elbows. If it is necessary to use components not given in the table
(examples: other duct cross-sections, elbows with other than 90 degree angles), it will be neces-
sary to refer to other texts or consult a duct design professional.
Table 2. Duct Sizes and Pressure Drops for Dryer Models
Air Specifications Duct components, sizes, and pressure drops
Dryer
Model
Prefix
Air flow
- scfm
(nlpm)
Velocity*
for given
cross-
section -
fpm
(mpm)
Equivalent** cross-sections Pressure drop - iwc (Pa)
Round
Rectangular*** Straight 90 Degree Elbows
Diame-
ter-in
(mm) Height-
in (mm)
Width-
in
(mm)
iwc per
100 feet
(or Pa
per 100
meters)
Smooth round
3-segment
round
Rectangular
Rs
Short
radius
Rl
Long
radius
Rs
Short
radius
Rl
Long
radius
Radius
-in
(mm)
iwc
(Pa)
50040
5040
5050
58040
3600
(101941)
2034
(620)
18 (457)
14 (356)
20
(508)
0.31 (253) 0.1 (25)
0.07
(17)
0.13
(32)
0.11
(27)
15 (381)
0.09
(22)
15 (381)
19
(483)
14.25
(362)
16 (406)
17
(432)
12.75
(324)
17 (432)
16
(406)
12 (305)
19 (483)
15
(381)
11.25
(286)
20 (508)
14
(356)
10.5
(267)
58058
5200
(147248)
2384
(727)
20 (508)
16 (406)
22
(559)
0.37 (302)
0.13
(32)
0.09
(22)
0.17
(42)
0.14
(35)
16.5
(419)
0.12
(30)
17 (432)
20
(508)
15 (381)
18 (457)
19
(483)
14.25
(362)
19 (483)
18
(457)
13.5
(343)
20 (508)
17
(432)
12.75
(324)
22 (559)
16
(406)
12 (305)
58080
Contact factory
6450 6000
(169901)
2400
(732)
22 (559) 20 (508) 19
(483)
0.30 (245) 0.09
(22)
0.06
(15)
0.18
(45)
0.14
(35)
14.25
(362)
0.12
(30)
6458
6464
8500
(240693)
2400
(732)
26 (660) 24 (610)
23
(584)
0.30 (245)
0.09
(22)
0.06
(15)
0.18
(45)
0.14
(35)
23 (584)
0.08
(20)
Air and Duct Requirements for Milnor ® Pass-through Dryers
53