Technical data

Installation
ACT 600 – 5000 11 – EN
4.5 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 95 100 105 110 115 122
ºC 27 32 35 38 40 43 45 50
Factor (F2) 1.11 1.09 1.06 1.00 0.94 0.87 0.78 0.69
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 600 has a nominal duty of 600 scfm (1019 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 = 600 x 1.07 x 0.78 x 0.68 x 1.36 = 463 scfm (787 m³/h)
463 scfm (787 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 = 750 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 =
750
= 972 scfm (1652 m³/h)
1.07 x 0.78 x 0.68 x 1.36
Therefore the model suitable for the conditions above is ACT 1000 (1000 scfm [1698 m³/h] - nominal
duty).