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T-Product · GIK, GIK..B · 2004 November
Sizing
Selection
For premix and modulating control of nozzle mix burn-
ers, select the GIK. For high-low control of nozzle mix
burners, including pulse firing, use the GIK..B regulator
with the internal bypass.
When used as cross-connected regulators, GIK turn-
down depends on the range of their outlet (loading) pres-
sures between high and low fire. The greater the range,
the greater the turndown. Always figure the turndown
before sizing the regulator, because this determines the
inlet pressure required.
Flow Turndown
Ratio
High Fire Outlet or Loading Pressure
Required to get Turndown if Low
Fire Loading Pressure is 0.2" WC
(0.5 mbar)
10 to 1 20" WC (50 mbar)
8 to 1 12.6" WC (32 mbar)
6 to 1 7.1" WC (18 mbar)
5 to 1 4.9" WC (12.5 mbar)
GIK..B Regulator turndown will depend on the sizing of
the internal bypass orifice.
1. Determine the gas pressure that will be supplied to
the regulator inlet and convert it from psig to ” WC
(psig x 27.7 = " WC). It should be at least equal to the
regulator’s high fire outlet pressure plus the pressure
drop across the regulator itself. The high fire outlet
pressure will be 0 for zero governors. On cross-con
-
nected nozzle-mixing applications, it will equal the
high fire outlet pressure determined under Turndown
above. For best results, the pressure drop across the
regulator should be about 10" WC. If the inlet pressure is considerably less than what’s needed, try to
obtain higher supply pressure. If this isn’t possible,
use a lower pressure drop across the regulator, but
don’t go below 2" WC.
2. Multiply the maximum gas flow through the regulator
by the correction factors for specific gravity, tempera
-
ture and altitude/line pressure from the tables below.
This is the corrected flow
.
Flow Correction Factors
Specific Gravity Factor
Air (1.0 s. g.) 1.27
Propane (1.56 s. g.) 1.61
Butane (2.00 s. g.) 1.83
Propane/Air (1.29 s. g.) 1.47
Coke Oven (0.45 s. g.) 0.87
Temperature Factor
60°F (16°C) 1.0
100°F (38°C) 0.96
120°F (46°C) 0.95
Line Pressure [psig]
Altitude
1 2 3
Sea Level 1.00 1.03 1.06
1000’ (305 m) 0.98 1.01 1.05
2000’ (610 m) 0.97 1.00 1.03
3000’ (915 m) 0.95 0.98 1.01
4000’ (1220 m) 0.93 0.97 1.00
5000’ (1525 m) 0.92 0.95 0.98
6000’ (1830 m) 0.90 0.94 0.97
7000’ (2135 m) 0.88 0.92 0.95