BAC HXI Series, Инструкция по эксплуатации и техническому обслуживанию, Страница: 6 / 40

W W W . B A L T I M O R E A I R C O I L . C O . Z A
GENERAL INFORMATION
Operating Conditions
BAC cooling equipment is designed for the operating conditions specified below, which must not be exceeded
during operation.
•
Wind Load : For safe operation of unshielded equipment exposed to wind speeds above 120 km/h installed at a
height above 30 m from the ground, contact your local BAC-Balticare representative.
• Seismic Risk : For safe operation of equipment installed in moderate and high hazard area's contact your local
BAC-Balticare representative.
Standard electrical motors are suitable for an ambient temperature range from -25°C to +40°C.
PRIME SURFACE COIL
Design pressure: max. 10 bar
Fluid inlet temperature: max. 82°C
Fluid outlet temperature: min. 10°C
Fluids circulated through the inside of the coils must be compatible with the coil construction material, ie.
•
black steel, for hot dip galvanized coils
• stainless steel AISI 304L or 316L (options)
• copper tubes when units are fitted with the optional finned discharge coil
Maximum spray pressure: 14 kPa (If pump(s) are installed by others, it is recommended to install a pressure gauge
at the inlet of the water distribution system.)
DRY FINNED COIL
The standard dry finned coil on the HXI Hybrid closed circuit cooling tower consists of a 6 row copper coil in a
staggered "triangle" arrangement with precoated aluminum high density fins. The coil is designed in accordance to
PED regulations and has an operating pressure of 10 bar.
OPERATING MODES
The hybrid closed Circuit Fluid Cooler operates under three different operating modes:
1.
Combined Dry-Wet Mode: During this mode, the process fluid flows through the finned coil bundle (sensible
heat transfer) and then through the wetted prime surface coil bundle (sensible and latent heat transfer). With
lower heat loads and/or ambient temperatures, the evaporative cooling portion (and hence the water usage) is
reduced by keeping the flow fed through the wetted prime surface coil bundle to a minimum. This is
accomplished by a modulating flow control valve, which controls the design outlet temperature.
2. Adiabatic Mode: During this mode, the process fluid flows through the finned coil bundle and by-passes the
wetted prime surface coil bundle completely. This entering ambient air is pre-humidified (cooled) by the spray
water before flowing over the high density finned coil bundle.
3. Dry Mode: The full process fluid flows through the finned coil bundle and the prime surface coil bundle. Since
the spray pump is turned off, only sensible heat transfer is used.
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HXI
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2 General Information
2 General Information