DFCV

1.0 Heat Exchanger

1.1 General: The finned Coil Heat Exchanger consists of either 1/2” or 5/8” O.D. phosphorus deoxidised copper seamless tubes and aluminium fins. Staggered tube construction provides substantially higher capacity since more tubes are exposed to the air stream. The advanced rippled-corrugated fin design creates a state of continuous turbulence, which effectively reduces the boundary layer formation that could otherwise reduce the rate of heat exchange. Fins have full drawn collars to maintain fin spacing and provide a continuous surface cover over the entire tube. The copper tubes are mechanically expanded into the fin collars to provide a continuous primary to secondary compression bond over the entire finned length for maximum heat transfer rates. Headers are made of seamless copper tubing and the coils are circuited for counterflow heat transfer to provide the maximum mean-effective temperature difference. The headers have steel male screw connections with 1/8” vent and drain. A full coil drain of the heat exchangers is not possible and as such Fluid Coolers operating under ambient temperatures that could drop below freezing point must contain liquid with an antifreeze agent. The entire coil block is pressure tested at 15 bar dry air submerged in warm water.

2.0 Air Movement

2.1 The air movement package: This air movement package combines premium aerodynamic and acoustic performance with innovative design to offer a compact fan and motor as an integrated product.

• Crenelated blades for the 800mm diameter fans provide low noise characteristics and increased efficiencies. The adjustable pitch angle impeller of the 900mm diameter fans, allows the optimum aerodynamic performance to be achieved for the given motor output, therefore minimising running costs.
• Exceptionally compact design with short overall motor length.
• Two speed by delta / star reconnection speed control.
• Minimal moving parts for maximum reliability.
• Motor protection IP55.
• Insulation Class F.
• Fan designed for frequent starting.
• Continuous running from -40ºC to 60ºC.
• Integral, overheat thermal cut-out protection.

2.2 Fan(s): The Fan has superb performance with a steep volume/pressure performance curve, giving greater flexibility in design and making it more “tolerant” of pressure variations which may occur because of, for instance, dirt accumulation on the fins of the heat exchanger. The fan, being an integrated product of impeller and motor, is balanced as a complete unit using dynamic single plane balancing. Balance grade is G6.3. The fan and motor are designed to be totally maintenance free.

2.3 Impeller: The one-piece impeller of the 800mm diameter fans is manufactured from glass coupled engineering polymers, which are UV stabilized. These have been developed using finite element stress analysis to provide a structural hub with a smooth transition into the blade form. Crenelated blades reduce sound levels and increase efficiency. Blade section thickness, consistent with providing sufficient strength, is kept to a minimum to further reduce noise.

The impeller of the 900mm diameter fans has an aluminum hub and clamp-plate, with six equally spaced, fully adjustable, moulded, black, ultra violet stabilized, glass coupled polypropylene airfoil section blades, designed on the latest aerospace technology.

2.4 Motor: Suitable for horizontal through to vertical shaft operation. IP55 protection, with removable drain plugs. Bearings lubricated with wide temperature range grease, re-lubricated or sealed for life depending on size. Insulation class F as standard. The motor is designed to give maximum flexibility of control by PWM Frequency Inverter, or Voltage Speed Control and where appropriate can be used to give two speeds by Delta/Star reconnect, where 80% of the full speed can be obtained by this method.

Electrical Supply

380 -420 V / 50 Hz / 3 ph

440- 480 V / 60 Hz / 3 ph

Motor Electrical Details

The motor can be run continuously from -40ºC to +60ºC.

A. Fans  800 mm

B. Fans 900 mm

Performance Data

The air and sound performance data has been measured in accordance with the following Standards:

• ISO 5801:1977, type A installation test method for air performance (dual numbered BS 848 Part1: 1997)
• BS 848 Part 2:1985, type A installation, method of noise testing.

3.0 Supporting Frame and Casing

3.1 Frame and Casing: The supporting Frame and Casing is an all-bolted painted galvanised steel construction designed to withstand the most adverse weather conditions. Double brake flanges maximise strength of panels. Full baffles separate individual fan sections.

Need more information? Contact your local BAC representative.