Housing |
The fan discharge apron shall be constructed of heavy gauge aluminum and shall
be spun on an automatic lathe to provide consistent dimensions. Heavy gauge
galvanized steel braces shall provide a sturdy support for the motor and drive
assembly. The discharge apron shall have a rolled bead for added strength.
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Base |
The base shall be constructed of galvanized steel for improved rigidity. Base
corners shall be welded to provide strength and to prevent leakage into the
building.
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Wheel |
The fan wheel shall be centrifugal backward
inclined and non-overloading. The wheel blades shall be
aerodynamically designed to minimize turbulence, increase efficiency and reduce
noise. The wheel blades shall be welded to the wheel inlet cone. In the event
that balancing weights are required they shall be riveted to the blades or wheel.
The wheel inlet shall overlap the fan base inlet for maximum performance and
efficiency. The wheel shall be firmly attached to the motor shaft with two set screws.
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Motor & Motor Compartment |
Motors shall be heavy duty ball bearing type, mounted out of the airstream and
furnished at the specified voltage, phase and enclosure. Motor mounting plate
shall be constructed of heavy gauge galvanized steel and isolated from the fan
structure with vibration isolators. The motor compartment shall be cooled by
outside air drawn through louvers in the cap. The motor compartment shall be
of a two-piece construction with the top cap having quick release clips to
provide quick and easy access to the motor compartment. An integral electrical
conduit running from the fan base to the motor compartment is provided for ease of
installation.
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Shaft & Bearings |
Shafts shall be precision ground and polished. Heavy duty, pre-lubricated
bearings shall be selected for a minimum (L10) life in excess of 200,000 hours
of operation at maximum cataloged operating speed. They shall be designed for,
and individually tested specifically for use in air handling applications.
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Belts & Drives |
Belts shall be oil and heat resistant, non-static type. Drives shall be cast
type, precision machined and keyed and securely attached to the fan and motor
shafts. Drives shall be sized for a minimum of 150% of the installed motor
horsepower. Fan operating speed shall be factory set using adjustable pitch
motor pulleys.
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Safety Disconnect Switch |
A safety disconnect switch shall be standard on all VCR units with open drip
proof motors. Switches shall be installed in a NEMA1 enclosure and mounted in
the motor compartment of the fan.
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Product: Fan shall be model VCR as manufactured by
Ventilation Direct.
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