Compressed Air Pipe Lines - Pressure Loss vs. Capacity and Operating Pressure

Pressure drop in compressed air pipe lines depends on line pressure, air flow and size of pipe. This calculator helps determine pressure loss in Schedule 40 steel pipes based on NPS, air flow (SCFM), and operating pressure.

NPS (in)	Line Pressure (psig)	Air Flow (SCFM)	Pressure Loss per 100 ft at 50 psig (psi)	Pressure Loss per 100 ft at 75 psig (psi)	Pressure Loss per 100 ft at 100 psig (psi)	Pressure Loss per 100 ft at 125 psig (psi)
1/2	50	10	0.7	0.5	0.4	0.3
1/2	75	20	2.7	2.0	1.6	1.3
1/2	100	30	5.9	4.3	3.4	2.8
1/2	125	40		7.5	5.8	4.8
1/2	150	50			9.0	7.4
1/2	175	60			12.9	10.6
3/4	50	10	0.2	0.15
3/4	75	20	0.9	0.5	0.4	0.3
3/4	125	50	3.8	2.7	2.1	1.8
3/4	200	80		6.8	5.2	4.4
3/4	250	100		10.6	8.3	7.0
3/4	312.5	125			12.9	10.7
3/4	375	150				13.9
1	75	20	0.2	0.1	0.1
1	125	50	1.1	0.8	0.6	0.5
1	187.5	75	2.6	1.7	1.3	1.1
1	250	100	4.1	3.0	2.3	1.9
1	312.5	125	6.3	4.5	3.5	2.9
1	375	150		6.5	5.1	4.2
1	500	200			8.9	7.3
1	625	250				11.3
1 1/2	125	50	0.1
1 1/2	187.5	75	0.3	0.2	0.15	0.1
1 1/2	250	100	0.5	0.3	0.3	0.2
1 1/2	312.5	125	0.7	0.5	0.4	0.3
1 1/2	375	150	1.0	0.8	0.6	0.5
1 1/2	500	200	1.8	1.3	1.0	0.8
1 1/2	625	250	2.8	2.0	1.6	1.3
1 1/2	750	300	4.0	2.9	2.3	1.9
1 1/2	1000	400	7.0	5.0	4.0	3.2
1 1/2	1250	500		7.8	6.2	5.1
1 1/2	1500	600			8.8	7.2
1 1/2	1750	700			11.9	9.8
1 1/2	2000	800				12.8
2	250	100	0.1
2	375	150	0.3	0.2	0.2	0.1
2	500	200	0.5	0.4	0.3	0.2
2	625	250	0.8	0.6	0.4	0.4
2	750	300	1.1	0.8	0.6	0.5
2	1000	400	1.9	1.4	1.1	0.9
2	1250	500	2.9	2.1	1.7	1.4
2	1500	600	4.2	3.0	2.4	2.0
2	2000	800		5.4	4.2	3.4
2	2500	1000		8.3	6.5	5.3
2	3125	1250			10.0	8.3
2	3750	1500				11.9
2 1/2	375	150	0.1
2 1/2	500	200	0.2	0.15	0.1
2 1/2	625	250	0.3	0.2	0.2	0.1
2 1/2	750	300	0.5	0.3	0.3	0.2
2 1/2	1000	400	0.8	0.6	0.5	0.4
2 1/2	1250	500	1.2	0.9	0.4	0.6
2 1/2	1500	600	1.7	1.3	1.0	0.8
2 1/2	2000	800	3.0	2.2	1.7	1.4
2 1/2	2500	1000	4.7	3.4	2.7	1.9
2 1/2	3125	1250	7.5	5.4	4.2	3.5
2 1/2	3750	1500		7.5	5.9	4.8
2 1/2	5000	2000			10.3	8.5
2 1/2	6250	2500				13.3
3	750	300	0.1	0.1
3	1250	500	0.4	0.3	0.2	0.2
3	1875	750	0.8	0.6	0.5	0.4
3	2500	1000	1.5	1.1	0.8	0.7
3	3750	1500	3.3	2.4	1.9	1.5
3	5000	2000	5.9	4.2	3.3	2.7
3	6250	2500		5.6	5.1	4.2
3	7500	3000		9.4	7.4	5.1
3	8750	3500			10.1	8.3
3	10000	4000			13.1	10.8
3	11250	4500				13.6
4	1875	750	0.2	0.15	0.1
4	2500	1000	0.4	0.3	0.2	0.2
4	3750	1500	0.8	0.6	0.5	0.4
4	5000	2000	1.5	1.1	0.8	0.7
4	6250	2500	2.2	1.6	1.3	1.1
4	7500	3000	3.2	2.3	1.8	1.5
4	10000	4000	5.7	3.4	3.2	2.6
4	12500	5000		6.3	5.0	4.1
4	15000	6000		9.0	7.1	6.8
4	17500	7000			9.7	7.9
4	20000	8000			12.7	10.3

Pressure Loss Reference Table

This table provides pressure loss data for Schedule 40 steel pipes under various operating conditions.

Notes:

All values are for pressure loss per 100 feet of pipe
Air flow is given in Standard Cubic Feet per Minute (SCFM) at standard conditions
Operating pressure values shown are: 50, 75, 100, and 125 psig
Pipe sizes range from 1/2 inch to 4 inches NPS
Empty cells indicate conditions where data is not available

How to Use:

Select your pipe size (NPS)
Find your operating pressure
Match your air flow (SCFM)
Read the pressure loss per 100 feet of pipe
Multiply by the actual pipe length and divide by 100 to get total pressure loss