Steam pipes and pressure drop diagrams - imperial and metric units

[Esam]

Pressure drop in steam pipes can be estimated with the diagrams below.
[h=Imperial Units]3[/h]
The diagram is made for steam with pressure 100 psi. For other pressures use correction factors:

Pressure (psi)	0	5	10	30	60	90	100	110	150	200	250	300
Factor	6.9	5.2	4.3	2.4	1.5	1.1	1.0	0.92	0.70	0.55	0.45	0.38

• 1 lbs/hr = 1.26x10^-4 kg/s
• 1 psi (lb/in²) = 6,894.8 Pa (N/m²) = 6.895x10^-3 N/mm² = 6.895x10^-2 bar = 27.71 in H₂O at 62^oF (16.7^oC) = 703.1 mm H₂O at 62^oF (16.7^oC) = 2.0416 in mercury at 62^oF (16.7^oC) = 51.8 mm mercury at 62^oF (16.7^oC) = 703.6 kg/m² = 0.06895 atm = 2.307 Ft. H₂O

[h=Metric Units]3[/h]
The diagram is made for steam with pressure 7 bar. For other pressures use correction factors:

Pressure (bar)	0	1	2	4	5	6	7	8.5	10	12	14	20
Factor	6.9	3.67	2.51	1.55	1.31	1.13	1.0	0.85	0.74	0.63	0.55	0.39

• 1 kg/h = 2.778x10^-4 kg/s = 3.67x10^-2 lb/min
• 1 bar = 10⁵ Pa (N/m²) = 0.1 N/mm² = 10,197 kp/m² = 10.20 m H₂O = 0.9869 atm = 14.50 psi (lb_f/in²) = 10⁶ dyn/cm² = 750 mmHg

[Esam]

[h=Calculate fluid flow and pipe velocity]2[/h]
[h=Imperial units]3[/h] A fluids flow velocity in pipes can be calculated with Imperial or American units as

v = 0.4085 q / d² (1)
where
v = velocity (ft/s)
q = volume flow (US gal. /min)
d = pipe inside diameter (inches)

[h=SI units]3[/h] A fluids flow velocity in pipes can be calculated with SI units as

v = 1.274 q / d² (2)
where
v = velocity (m/s)
q = volume flow (m³/s)
d = pipe inside diameter (m)