Fluid Flow Velocities
Guidelines for the acceptable ranges of flow velocity for various fluids found in a sugar factory
Goodall
|
Velocity [m/s] |
Water for space heating |
2 |
4 |
Water for boiler feed |
3 |
6 |
Saturated steam |
30 |
50 |
Superheated steam |
50 |
100 |
Hugot
|
Velocity [m/s] |
Superheated steam |
40 |
76 |
Saturated steam |
24 |
37 |
Exhaust (wet/oily) |
31 |
46 |
Bled vapour |
37 |
49 |
Vapour under vacuum |
46 |
76 |
Suction |
Water |
1 |
1.25 |
Juice |
1 |
1.2 |
Syrup |
0.5 |
1 |
Molasses |
0.25 |
0.5 |
Massecuites |
0.1 |
0.2 |
Delivery |
Water |
1.25 |
2.5 |
Juice |
1.2 |
2 |
Syrup |
0.75 |
1.25 |
Molasses |
0.5 |
0.75 |
Massecuites |
0.15 |
0.3 |
Lyle
|
Velocity [m/s] |
Water |
1.22 |
2.44 |
Superheated steam |
46 |
61 |
Dry saturated steam |
31 |
40 |
Wet exhaust steam |
21 |
31 |
Moderate vacuum water vapour |
46 |
61 |
High vacuum water vapour |
61 |
107 |
Babcock & Wilcox
|
Velocity [m/s] |
High pressure steam |
41 |
61 |
Low pressure steam |
61 |
76 |
Water general |
2.54 |
3.81 |
From a source on the internet
Maximal velocity in pipes
Water |
m/s |
ft/s |
Tap water (low noise) |
0.5 - 0.7 |
1.6 -8.2 |
Tap water |
1.0 - 2.5 |
3.3 - 8.2 |
Cooling water |
1.5 - 2.5 |
4.9 - 8.2 |
Boiler feed water. suction |
0.5 - 1.0 |
1.6 - 3.3 |
Boiler feed water. discharge |
1.5 - 2.5 |
4.9 - 8.2 |
Condensate |
1.0 - 2.0 |
3.3 - 6.5 |
Heating circulation |
1.0 - 3.0 |
3.3 - 9.8 |
Steam |
m/s |
ft/s |
Saturated Steam. high pressure |
25 - 40 |
82 - 131 |
Saturated Steam. in special cases |
- 60 |
- 197 |
Saturated Steam. medium and low pressure |
30-40 |
99 - 131 |
Saturated Steam. at peak load |
- 50 |
- 164 |
Steam / Water emulsion |
- 25 |
- 82 |
Oil |
m/s |
ft/s |
Suction lines for pumps |
- 0.5 |
-1.6 |
Suction lines for pump (low pressure) |
0.1 - 0.2 |
0.3 - 0.65 |
Discharge line for booster pump |
1.0 - 2.0 |
3.3 - 6.5 |
Discharge line for burner pump |
- 1.0 |
- 3.3 |
Air |
m/s |
ft/s |
Combustion air ducts |
12 - 20 |
40 - 66 |
Air inlet to boiler room |
1 - 3 |
3.3 - 9.8 |
Warm air for house heating |
0.8 - 1.0 |
2.6 - 3.3 |
Vacuum cleaning pipe |
8 - 15 |
26 - 49 |
Compressed air pipe |
20 - 30 |
66 - 98 |
Ventilation ducts (hospitals) |
1.8 - 4 |
5.9 - 13 |
Ventilation ducts (office buildings) |
2.0 - 4.5 |
6.5 - 15 |
Exhaust gas |
m/s |
ft/s |
Ducts at minimum load |
- 4.0 |
- 13 |
Stack at minimum load |
- 5.0 |
- 16 |
Boiler with one-step burner (on - off) |
5.0 - 8.0 |
16 - 26 |
Boiler with two-step burner (high - low) |
10 - 15 |
31 - 49 |
Boiler with modulating burner (3:1) |
15 - 25 |
49 - 82 |
To keep the surface free from soot the velocity should always exceed |
3.0 - 4.0 |
9.8 - 13 |
It is recommended that the maximum inlet velocities applied to control valves should be as shown in the tables
below.
Gate Valve Size |
Liquid |
Steam or Gas |
mm |
m/s |
ft/s |
m/s |
ft/s |
15 - 25 |
9 |
30 |
120 |
400 |
40 - 50 |
7.5 |
25 |
90 |
300 |
65 - 100 |
6 |
20 |
75 |
250 |
150 - 200 |
6 |
20 |
70 |
225 |
250 - 400 |
4.5 |
15 |
55 |
175 |
Angle Valves Size |
Liquid |
Steam or Gas |
mm |
m/s |
ft/s |
m/s |
ft/s |
15 - 25 |
13.5 |
45 |
135 |
450 |
40 - 50 |
12 |
40 |
105 |
350 |
65 - 100 |
10.5 |
35 |
90 |
300 |
150 - 200 |
9 |
30 |
85 |
275 |
250 - 400 |
7.5 |
25 |
70 |
225 |
References
- Goodall, Efficient Use of Steam, pg 192 Table 9.5
- Hugot, Handbook of Cane Sugar Engineering, pg 1058 Table 47.6 and pg 1123 Table 45.2
- Lyle, Efficient Use of Steam, pg 132 Table XXVII
- Babcock & Wilcox, Steam: Its Generation and Usage
- http://www.steamesteem.com/index.html?tables