CPT International 02/2021

MOLD AND COREMAKING
Energy consumption
Effectiveness
27%~34% 33%~41% 25%~40%
~25 kW
Dry cycle time
~30 kW
Sand shooting
exhaust
Curing time
18 kWCold core process
36 kWInorganic technology
Figure 3: The relationship between power distribution and energy consumption of the main
functions of the traditional core machine
(1) The heater body is integrated with the gassing channel
and electric heating element, (2) Blowing air duct (3) Air inlet
(4) Air outlet (5) Electric heating element (6) Amine injection port
(7) Heat insulation (8) Gassing bell (9) Core box (10) Sand core
Figure 4: Schematic diagram of the functional integration.
2030sCold core process 80%
3050sInorganic technology 80%
Figure 2: The relationship between core-making cycle time and efficiency using the
traditional method.
P
integrated with the blowing hood of
the core making machine.
> Functional integration: heater and
cold core process catalyst atomization
accomplish afunctional integration.
The schematic diagram of the functional
integration is shown in Figure 4,
whereas the schematic diagram of the
integrated solution is shown in Figure 5.
Compared to the traditional scheme,
the other mechanisms are the same, but
the heater is integrated on the blowing
hood, eliminating the traditional
connecting hose assembly.
According tothe current structure of
the key functional component of the
heater, its physical shape and the geometric
model of the fluid channel area
are preprocessed, and the flow and
heat exchange process of the heater are
simulated and analyzed according to
the operating conditions of the heater
(Figure 6):
> The three-dimensional flow trajectory
diagram of the gas in the heater
channel and the core area diagram of
the air flow vortex are obtained
through simulation, and the air inlet
Reynolds number, obtained through
simulation, is within the “strong turbulence”
stage.
> The heater is designed to simultaneously
introduce gas into both sets of
flow channels. Since the channel geometric
structure is symmetrically similar,
the gas flow in the two sets of flow
channels also exhibits asymmetrically
distributed flow pattern.
> Itcan be seen from the schematic
diagram that within the heater flow
channels, the gas flow state in most
areas is aturbulent vortex flow, sothe
heating and heat exchange efficiency of
the heater is relatively high.
Table 1: Verification results of the integration scheme (with a40l-core making machine as an example).
Performance Traditional solution Integrated solution Trend Parameter
Heatloss in % 50-60 10-20 reduce 30-50
Curing energy
0.009 0.0045 reduce 50%
consumption in Kwh/kg (Cold
core process only)
Catalyst consumption
1-1.5ml/kg 0.5-0.7 reduce 30-50%
(Catalystdosage/sand core
Weightinml/kg,cold core process
only)
Curing efficiency
Curing time in s
reduce 30-50%
Exhaust system processing
airvolumeinm 3 /h
20-30 (Cold core
process)
30-50 ((Inorganic
-technology)
10-20 (Cold core
process)
15-25 (Inorganic
technology)
50 %
About 8000 About 3500 reduce 40-50%
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