Measurement and Conversion Charts
Chart 1:
| CFM requirements for diameter at specified velocity | |||
|---|---|---|---|
| Diameter | 3500 FPM | 4000 FPM | 4500 FPM |
| 3″ | 170 | 195 | 220 |
| 4″ | 300 | 350 | 390 |
| 5″ | 475 | 550 | 610 |
| 6″ | 700 | 785 | 880 |
| 7″ | 950 | 1100 | 1200 |
| 8″ | 1200 | 1400 | 1570 |
| 9″ | 1550 | 1800 | 1990 |
| 10″ | 1900 | 2200 | 2450 |
| 12″ | 2800 | 3175 | 3600 |
| 14″ | 3800 | 4300 | 4800 |
Chart 2:
| Static Pressure based on 100′ of Pipe | |||
|---|---|---|---|
| Diameter | 3500 FPM | 4000 FPM | 4500 FPM |
| 3″ | 7.5 | 10.0 | 12.0 |
| 4″ | 5.5 | 7.0 | 8.5 |
| 5″ | 4.2 | 5.5 | 6.5 |
| 6″ | 3.5 | 4.5 | 5.5 |
| 7″ | 2.8 | 3.8 | 4.5 |
| 8″ | 2.4 | 3.2 | 3.8 |
| 9″ | 2.0 | 2.8 | 3.4 |
| 10″ | 1.8 | 2.4 | 3.0 |
| 12″ | 1.2 | 2.0 | 2.5 |
| 14″ | 1.3 | 1.6 | 2.0 |
Chart 3:
| Elbow to Straight Pipe Conversion | |||
|---|---|---|---|
| Diameter | 90° Elbow 1.5 Diameter Rad. | 45° Elbow 1.5 Diameter Rad. | |
| 3″ | 5′ | 2.5′ | |
| 4″ | 6′ | 3′ | |
| 5″ | 9′ | 4.5′ | |
| 6″ | 12′ | 6′ | |
| 7″ | 12′ | 6.5′ | |
| 8″ | 15′ | 7.5′ | |
| 9″ | 17.5′ | 8.75′ | |
| 10″ | 20′ | 10′ | |
| 12″ | 25′ | 12.5′ | |
| 14″ | 30′ | 15′ | |