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47
Vol. 2.6 © 2020 Hanbell Precise Machinery Co., Ltd. All rights reserved
Table 3.5 Fixed-frequency compressor safety margin line formula
Warning
:
:
:
:
Safety margin line formula is the primary protection of compressor surge, DO NOT use
current detection only for surge protection as it only passively activated when surge
occurs. Compressor will be seriously damaged by repeating occurrence of surge.
IGV(%)
100
90
80
70
60
50
40
30
20
10
Pr
3.13
3.11
3.09
3.08
3.07
3.04
3.01
2.96
2.90
2.81
IGV(%)
100
90
80
70
60
50
40
30
20
10
Pr
3.13
3.10
3.07
3.04
3.01
2.96
2.90
2.82
2.72
2.60
IGV(%)
100
90
80
70
60
50
40
30
20
10
Pr
3.21
3.19
3.18
3.16
3.15
3.13
3.09
3.04
2.97
2.89
IGV(%)
100
90
80
70
60
50
40
30
20
10
Pr
3.21
3.18
3.15
3.12
3.09
3.04
2.98
2.90
2.80
2.67
IGV(%)
100
90
80
70
60
50
40
30
20
10
Pr
2.97
2.95
2.93
2.92
2.91
2.89
2.85
2.81
2.74
2.66
IGV(%)
100
90
80
70
60
50
40
30
20
10
Pr
2.96
2.94
2.91
2.88
2.85
2.80
2.75
2.67
2.58
2.46
IGV(%)
100
90
80
70
60
50
40
30
20
10
Pr
3.66
3.63
3.62
3.61
3.59
3.52
3.40
3.22
2.98
2.66
e
2.00
4.16545E-02
-3.06201E-04
-1.38454E-06
1.66588E-08
-1.61850E-04
6.98360E-07
-5.66460E-10
RT-111
RT-161
RT-221
y=2.27349+4.16545E-02x-3.06201E-04x
2
-1.38454E-06x
3
+1.66588E-08x
4
constant
a
b
c
d
RT-160T
⌇
RT-280T
y=2.3101+1.6313E-02x-1.6185E-04x
2
+6.9836E-07x
3
-5.6646E-10x
4
constant
a
b
c
d
e
2.00
1.63130E-02
e
2.00
1.18314E-02
-1.22987E-04
3.07100E-07
1.53292E-09
-1.72966E-04
7.51568E-07
-6.36018E-10
RT-160(E)
⌇
RT-280(E)
y=2.55474+1.18314E-02x-1.22987E-04x
2
+3.07100E-07x
3
+1.53292E-09x
4
constant
a
b
c
d
RT-130T
RT-140T
y=2.51204+1.73806E-02x-1.72966E-04x
2
+7.51568E-07x
3
-6.36018E-10x
4
constant
a
b
c
d
e
2.00
1.73806E-02
e
2.00
1.25863E-02
-1.31003E-04
3.29367E-07
1.61811E-09
-1.69203E-04
7.33557E-07
-6.12448E-10
RT-130(E)
RT-140(E)
y=2.77262+1.25863E-02x-1.31003E-04x
2
+3.29367E-07x
3
+1.61811E-09x
4
constant
a
b
c
d
RT-120T
y=2.44328+1.70194E-02x-1.69203E-04x
2
+7.33557E-07x
3
-6.12448E-10x
4
constant
a
b
c
d
e
2.00
1.70194E-02
e
2.00
1.23309E-02
-1.28291E-04
3.21830E-07
1.58931E-09
Model
Pr=a+bx+cx
2
+dx
3
+ex
4
x=IGV opening(10~100) y=Pr (Max.safety pressure ratio)
RT-120(E)
y=2.69848+1.23309E-02x-1.28291E-04x
2
+3.21830E-07x
3
+1.58931E-09x
4
constant
a
b
c
d