Engineering Bulletin

Engineering Data
121
821, 831, 92 Series and 98VOH (Page 36-38, 41)
Deflection E
Deflection G
Face Velocity 400 500 600 700 800 900 1000 1100 1200 1300 1400 1600 1800 2000
Pressure Loss .010 .016 .022 .031 .040 .050 .062 .075 .090 .105 .122 .160 .202 .249
8x4
Ak .124
cfm
Throw
50
3.5
60
4.5
75
5.5
85
6
100
7.5
110
8
125
9
135
10
150
11
160
12
175
13
200
15
225
16
250
18
10x4
Ak .157
cfm
Throw
65
4
80
5
95
6
110
7
125
8
140
9
155
10
175
11
190
12
205
13
220
14
250
16
285
19
315
20
12x4
Ak .190
cfm
Throw
75
4.5
95
5.5
115
7
135
8
150
9
170
10
190
11
210
12
230
14
245
15
265
16
305
18
340
20
380
22
14x4
Ak .222
cfm
Throw
90
5
110
6
135
7.5
155
8.5
180
10
200
11
220
12
245
13
265
14
290
16
310
17
355
19
400
22
445
24
12x5
Ak .242
cfm
Throw
95
5
120
6.5
145
7.5
170
9
195
10
220
12
240
13
265
14
290
15
315
17
340
18
385
20
435
23
485
25
10x6
Ak .244
cfm
Throw
100
5
120
6.5
145
7.5
170
9
195
10
220
11
245
13
270
14
295
15
315
16
340
18
390
20
440
23
490
26
14x5
Ak .284
cfm
Throw
115
5.5
140
7
170
8
200
9.5
225
11
255
12
285
14
310
15
340
16
370
18
400
19
455
22
510
25
570
28
12x6
Ak .294
cfm
Throw
120
5.5
145
7
175
8.5
205
9.5
235
11
265
13
295
14
325
15
355
17
380
18
410
19
470
22
530
25
590
28
16x5
Ak .325
cfm
Throw
130
6
165
7.5
195
9
230
10
260
12
295
13
325
15
360
16
390
18
425
19
455
21
520
24
585
26
650
29
14x6
Ak .345
cfm
Throw
140
6
175
7.5
205
9
240
11
275
12
310
14
345
15
380
17
415
18
450
20
485
21
550
24
620
27
690
30
16x6
Ak .396
cfm
Throw
160
6.5
200
8
240
10
275
11
315
13
355
15
395
16
435
18
475
19
515
21
555
23
635
26
715
29
790
32
20x5
Ak .408
cfm
Throw
165
6.5
205
8.5
245
10
285
11
325
13
365
15
410
17
450
18
490
20
530
21
570
23
655
26
735
30
815
33
24x5
Ak .492
cfm
Throw
195
7
245
9
295
11
345
13
395
14
445
16
490
18
540
20
590
22
640
23
690
25
785
29
885
32
985
36
20x6
Ak .497
cfm
Throw
200
7.5
250
9
300
11
350
13
400
15
445
16
495
18
545
20
595
22
645
24
695
25
795
29
895
33
995
36
24x6
Ak .598
cfm
Throw
240
8
300
10
360
12
420
14
480
16
540
18
600
20
660
22
720
24
775
26
835
28
955
32
1075
36
1195
40
20x8
Ak .673
cfm
Throw
270
8.5
335
11
405
13
470
15
540
17
605
19
675
21
740
23
810
25
875
27
940
30
1075
34
1210
38
1345
42
30x6
Ak .750
cfm
Throw
300
9
375
11
450
13
525
16
600
18
675
20
750
22
825
25
900
27
975
29
1050
31
1200
36
1350
40
1500
45
24x8
Ak .811
cfm
Throw
325
9.5
405
12
485
14
570
16
650
19
730
21
810
23
890
25
975
28
1055
30
1135
32
1300
37
1460
42
1620
46
30x8
Ak 1.017
cfm
Throw
405
11
510
13
610
16
710
18
815
21
915
23
1015
26
1120
29
1220
31
1320
34
1425
36
1625
42
1830
47
2035
52
24x10
Ak 1.023
cfm
Throw
410
10
510
13
615
16
715
18
820
21
920
23
1025
26
1125
29
1230
31
1330
34
1430
36
1635
42
1840
47
2045
52
36x8
Ak 1.222
cfm
Throw
490
11
610
14
735
17
855
20
980
23
1100
26
1220
28
1345
31
1465
34
1590
37
1710
40
1955
46
2200
51
2445
57
24x12
Ak 1.236
cfm
Throw
495
11
620
14
740
17
865
20
990
23
1110
26
1235
29
1360
32
1485
34
1605
37
1730
40
1975
46
2225
52
2470
57
30x10
Ak 1.283
cfm
Throw
515
12
640
15
770
17
900
20
1025
23
1155
26
1285
29
1410
32
1540
35
1670
38
1795
42
2055
46
2310
52
2565
58
36x10
Ak 1.543
cfm
Throw
615
13
770
16
925
19
1080
22
1235
26
1390
29
1545
32
1700
35
1850
38
2005
42
2160
45
2470
51
2775
57
3085
64
30x12
Ak 1.550
cfm
Throw
620
13
775
16
930
19
1085
22
1240
26
1395
29
1550
32
1705
35
1860
39
2015
2170
45
2480
51
2790
58
3100
64
36x12
Ak 1.864
cfm
Throw
745
14
930
18
1120
21
1305
25
1490
28
1680
32
1865
35
2050
39
2235
42
2425
46
2610
49
2980
56
3355
63
3730
70
Terminal Velocity of 75 fpm
* less than or equal to ** greater than or equal to
*NC 30 NC 35 NC 40 **NC 45
Face Velocity 400 500 600 700 800 900 1000 1100 1200 1300 1400 1600 1800 2000
Pressure Loss .010 .016 .022 .031 .040 .050 .062 .075 .090 .105 .122 .160 .202 .249
8x4
Ak .119
cfm
Throw
50
2.5
60
3
70
4
85
4.5
95
5
105
5.5
120
6.5
130
7
145
8
155
8.5
165
9
190
10
215
12
240
13
10x4
Ak .143
cfm
Throw
55
2.5
70
3.5
85
4
100
5
115
5.5
130
6.5
145
7
155
7.5
170
8
185
9
200
9.5
230
11
255
12
285
14
12x4
Ak .173
cfm
Throw
70
3
85
3.5
105
4.5
120
5.5
140
6
155
7
175
7.5
190
8.5
210
9
225
10
240
11
275
12
310
14
345
15
14x4
Ak .202
cfm
Throw
80
3
100
4
120
5
140
5.5
160
6.5
180
7.5
200
8
220
9
240
9.5
265
11
285
12
325
13
365
15
405
16
12x5
Ak .220
cfm
Throw
90
3.5
110
4.5
130
5
155
6
175
7
200
8
220
8.5
240
9.5
265
10
285
11
310
12
350
14
395
15
440
17
10x6
Ak .222
cfm
Throw
90
3.5
110
4.5
135
5
155
6
180
7
200
7.5
220
8.5
245
9.5
265
10
290
11
310
12
355
14
400
15
445
17
14x5
Ak .258
cfm
Throw
105
4
130
4.5
155
5.5
180
6.5
205
7.5
230
8.5
260
9.5
285
10
310
11
335
12
360
13
415
15
465
17
515
18
12x6
Ak .268
cfm
Throw
105
4
135
5
160
5.5
190
6.5
215
7.5
240
8.5
270
9.5
295
10
320
11
350
12
375
13
430
15
480
17
535
19
16x5
Ak .296
cfm
Throw
120
4
150
5
180
6
205
7
235
8
265
9
295
10
325
11
355
12
385
13
415
14
475
16
535
18
590
20
14x6
Ak .314
cfm
Throw
125
4
155
5
190
6
220
7
250
8
285
9.5
315
10
345
11
375
12
410
13
440
14
500
16
565
18
630
20
16x6
Ak .360
cfm
Throw
145
4.5
180
5.5
215
6.5
250
7.5
290
9
325
10
360
11
395
12
430
13
470
14
505
15
575
17
650
20
720
22
20x5
Ak .372
cfm
Throw
150
4.5
185
5.5
225
6.5
260
7.5
300
9
335
10
370
11
410
12
445
13
485
14
520
15
595
18
670
20
745
22
24x5
Ak .448
cfm
Throw
180
5
225
7.5
270
7.5
315
8.5
360
10
405
11
450
12
495
13
540
15
580
16
625
17
715
19
805
22
895
24
20x6
Ak .453
cfm
Throw
180
5
225
6
270
7.5
315
8.5
360
10
410
11
455
12
500
14
545
15
590
16
635
17
725
20
815
22
905
25
24x6
Ak .545
cfm
Throw
220
5.5
275
7
325
8
380
9.5
435
11
490
12
545
13
600
15
655
16
710
18
765
19
870
21
980
24
1090
27
20x8
Ak .614
cfm
Throw
245
5.5
305
7
370
8.5
430
10
490
11
555
13
615
14
675
16
735
17
800
19
860
20
980
23
1105
26
1230
29
30x6
Ak .683
cfm
Throw
275
6
340
7.5
410
9
480
11
545
12
615
14
685
15
750
17
820
18
890
20
955
21
1095
24
1230
27
1365
30
24x8
Ak .739
cfm
Throw
295
6.5
370
8
445
9.5
515
11
590
13
665
14
740
16
815
17
885
19
960
20
1035
22
1180
25
1330
28
1480
31
30x8
Ak .926
cfm
Throw
370
7
465
9
555
10
650
12
740
14
835
16
925
17
1020
19
1110
21
1205
23
1295
24
1480
28
1665
31
1850
35
24x10
Ak .932
cfm
Throw
375
7
465
9
560
11
650
12
745
14
840
16
930
18
1025
19
1120
21
1210
23
1305
25
1490
28
1675
32
1865
35
36x8
Ak 1.114
cfm
Throw
445
7.5
555
9.5
670
12
780
13
890
15
1005
17
1115
19
1225
21
1335
23
1450
25
1560
27
1780
31
2005
35
2230
39
24x12
Ak 1.126
cfm
Throw
450
7.5
565
9.5
675
12
790
14
900
15
1015
17
1125
19
1240
21
1350
23
1465
25
1575
27
1800
31
2025
35
2250
39
30x10
Ak 1.169
cfm
Throw
470
8
585
10
700
12
820
14
935
16
1050
18
1170
20
1285
22
1405
24
1520
26
1635
27
1870
31
2105
35
2340
39
36x10
Ak 1.406
cfm
Throw
560
8.5
705
11
845
13
985
15
1125
17
1265
19
1405
22
1545
24
1685
26
1830
28
1970
30
2250
35
2530
39
2810
43
30x12
Ak 1.412
cfm
Throw
565
8.5
705
11
845
13
990
15
1130
17
1270
19
1410
22
1555
24
1695
26
1835
28
1975
30
2260
35
2540
39
2825
43
36x12
Ak 1.698
cfm
Throw
680
9.5
850
12
1020
14
1190
17
1360
19
1530
21
1700
24
1870
26
2040
29
2210
31
2375
33
2715
38
3055
43
3395
48
See Alternate Sizing Graph on Page 160.
See Deflections on Page 158.