مقدار جریان هوا از طریق منافذ (Air Flow Through Orifices)

Volume of free air in CFM that will flow thru round holes from a receiver into the atmosphere. Cubic feet of air per minute measured at absolute pressure of 14.7 lbs. per sq. in. and 70¼ F.

 

Air Flow Through Orifices

Dia. of
Orifice
(In.)

Guage Pressure in Reciever - Pounds

2

5

10

15

20

25

30

35

40

45

50

60

70

80

90

100

125

150

200

1/64

0.04

0.062

0.077

0.105

0.123

0.14

0.158

0.176

0.194

0.211

0.29

0.267

0.3

0.335

0.37

0.406

0.494

0.583

0.75

1/32

0.158

0.248

0.311

0.42

0.491

0.562

0.633

0.703

0.774

0.845

0.916

1.06

1.2

1.34

1.48

1.62

1.98

2.32

3.18

3/64

0.356

0.568

0.712

0.944

1.1

1.26

1.42

1.58

1.75

1.91

2.06

2.38

2.7

3

3.33

3.66

4.44

5.25

6.86

1/16

0.633

0.993

1.24

1.68

1.96

2.25

2.53

2.81

3.1

3.38

3.66

4.23

4.79

5.36

5.92

6.49

7.9

9.1

12.17

3/32

1.43

2.23

2.8

3.78

4.41

5.05

5.69

6.31

7

7.63

8.25

9.5

10.8

12

13.3

14.6

17.8

20.9

27.35

1/8

2.53

3.97

4.98

6.72

7.86

8.98

10.1

11.3

12.4

13.5

14.7

16.9

19.2

21.4

23.7

26

31.6

37.3

48.7

3/16

5.7

8.93

11.2

15.2

17.65

20.2

22.8

25.2

28

30.5

33

38

43.2

48.3

53.2

58.5

71

84

109.6

1/4

10.1

15.9

19.9

26.9

31.4

35.9

40.5

45

49.6

54.1

58.6

67.6

76.7

85.7

94.8

104

126

149.3

195

3/8

22.8

35.7

44.7

60.5

70.7

80.9

91.1

101

112

122

132

152

173

193

213

234

284

336

438

1/2

40..5

63.5

79.6

108

126

144

162

180

198

216

235

271

307

343

379

415

506

596

777

5/8

63.03

99.3

124.5

168

196

225

253

281

310

338

366

423

479

536

592

649

790

932

1216

3/4

91.2

143

179.2

242

283

323

365

405

446

487

528

609

690

771

853

934

1138

1340

1750

7/8

124

195

244.2

329

385

440

496

551

607

662

718

828

939

1050

1161

1272

1549

1825

2382

1

162

254

318.2

430

503

575

648

720

793

865

938

1082

1227

1371

1516

1661

2023

2385

3112

1 - 1/8

205

321

402.5

544

637

727

820

910

1004

1094

1187

1370

1552

1734

1918

2101

2560

3020

3940

1 - 1/4

253

397

498

672

784

900

1019

1124

1240

1352

1464

1693

1917

2144

2370

2596

3160

3725

4860

1 - 3/8

307

482

604

816

954

1091

1230

1367

1505

1643

1780

2054

2330

2607

2880

3153

3840

4525

5910

1-1/2

364

572

716

968

1132

1293

1460

1620

1783

1946

2112

2335

2760

3081

3412

3734

4550

5360

7000

1 - 3/4

496

780

972

1318

1540

1760

1985

2205

2429

2650

2875

3310

3755

4200

4645

5085

6195

7300

9530

2

648

1015

1274

1720

2120

2300

2594

2880

3173

3460

3752

4330

4915

5480

6070

6650

8100

9540

12450

 

 

Table is based on 100% coefficient of flow. For well rounded entrance, multiply values by 0.97. For sharp edge orifices, a multiplier of 0.65 may be used. This table will give approximate results only. The formula Q=14.5 PD2, where Q is CFM, P is absolute pressure and D is orifice diameter in inches, may be used for any points not given in table. (Applies only above 15 pounds gauge.)