Installation
14
– EN
ACT VS 3000 - 6000
8.3
Correction factors
Correction factor for operating pressure changes:
Inlet air pressure
psig
60
80
100
120
140
160
180
203
barg
4
5.5
7
8
10
11
12
14
Factor (F1)
0.79
0.91
1.00
1.07
1.13
1.18
1.23
1.27
Correction factor for ambient temperature changes (Air-Cooled):
Ambient temperature
ºF
80
90
95
100
105
110
115
ºC
27
32
35
38
40
43
45
Factor (F2)
1.11
1.09
1.06
1.00
0.94
0.87
0.78
Correction factor for inlet air temperature changes:
Air temperature
ºF
90
100
110
122
130
140
150
158
ºC
32
38
43
50
55
60
65
70
Factor (F3)
1.16
1.00
0.82
0.68
0.61
0.52
0.45
0.40
Correction factor for DewPoint changes:
DewPoint
ºF
38
41
45
50
ºC
3
5
7
10
Factor (F4)
1.00
1.08
1.20
1.36
How to find the air flow capacity:
Air flow capacity = Nominal duty x Factor (F1) x Factor (F2) x Factor (F3) x Factor (F4)
Example:
An
ACT VS 3000
has a nominal duty of 3000 scfm (5097 m³/h). What is the maximum allowable flow through the
dryer under the following operating conditions:
Inlet air pressure = 120 psig (8 barg)
Ambient temperature = 115°F (45°C)
Inlet air temperature = 122°F (50°C)
Pressure DewPoint = 50°F (10°C)
Factor (F1) = 1.07
Factor (F2) = 0.78
Factor (F3) = 0.68
Factor (F4) = 1.36
Each item of data has a corresponding numerical factor which multiplied by the design air flow is as follows:
Air flow capacity = 3000 x 1.07 x 0.78 x 0.68 x 1.36 = 2316 scfm (3935 m³/h)
2316 scfm (3935 m³/h)
This is the maximum flow rate that the dryer can accept under these operating conditions.
How to select a suitable dryer for a given duty:
Minimum std. air flow rate =
Design air flow
Factor (F1) x Factor (F2) x Factor (F3) x Factor (F4)
Example:
With the following operating parameters:
Design air flow = 3500 scfm (1274 m
3
/h)
Inlet air pressure = 120 psig (8 barg)
Ambient temperature = 115°F (45°C)
Inlet air temperature = 122°F (50°C)
Pressure DewPoint = 50°F (10°C)
Factor (F1) = 1.07
Factor (F2) = 0.78
Factor (F3) = 0.68
Factor (F4) = 1.36
In order to select the correct dryer model the required flow rate is to be divided by the correction factors relating to
above mentioned parameters:
Minimum std. air flow rate =
3500
= 4535 scfm (7705 m³/h)
1.07 x 0.78 x 0.68 x 1.36
Therefore the model suitable for the conditions above is
ACT VS 5000
(
5000 scfm [8490 m³/h]
- nominal duty).
