SPX Cooling Technologies Cooling Tower 160 - Manual (Page 4)

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Class 160 towers offer the benefits of adjustable pitch
propeller type fans. All fans used on Class 160 towers include
hollow GRE (glass-reinforced epoxy) blades and epoxy-coated
cast iron or galvanized steel hubs. Blades are adjustable in
pitch, so you can take full advantage of rated horsepower or
adjust the pitch to compensate for unusual jobsite restrictions.
The true airfoil blades, designed specifically for cooling towers,
offer efficient, quiet operation and long service life.
■ Water Distribution System
The gravity-flow water distribution system designed into the
Class 160 tower essentially reduces pump head to its most
basic component—static lift—saving you money on pump
power. You won’t have to force water through internal piping
and pressure spray nozzles, as you would in a counterflow
tower.
Warm water enters the system through a Marley galvanized
crossover pipe. Inlet connections for your piping are drilled to
conform to Class 125 ANSI requirements. Marley flow-control
valves balance the flow to both distribution basins of each
cell. Water flows from the valves through a splash-suppression
chamber and into the treated fir plywood distribution basins.
Polypropylene Marley “Spiral Target” nozzles in the basin
Fans operate inside structural FRP (fiber-reinforced
polyester) eased-inlet fan cylinders designed and applied to
maximize fan performance. Standard cylinder heights are
6
′-0″ to 7′-0″, depending on fan diameter. 10′-0″ cylinders are
available as an option.
Marley-manufactured driveshafts transmit power from the
motor to the Geareducer assembly. All Marley driveshafts
include 304 stainless steel tubes with welded-on stainless
steel flanges and bonded neoprene flexible elements to
transmit torque. Marley driveshafts are full-floating assemblies
with non-lubricated flexible couplings on each end. Their
tolerance to misalignment and torsional shock is unequalled
in non-specialized units. All Marley driveshafts are dynamically
balanced at the factory to minimize operating vibrations.
Welded unitized hot dip galvanized steel supports maintain
alignment throughout the mechanical equipment system.
Marley torque-tubes provide superior strength and stability.
Their cylindrical shape also keeps operating costs down by
minimizing airflow restrictions and reducing air turbulence in
the fan entrance region.
floor then distribute the water uniformly over the fill.
All materials in the water distribution system offer long life
and minimal maintenance. Valves consist of cast iron bodies
and grease-lubricated stainless steel operating stems. All
plywood is treated exterior grade. The nozzles are chemically
and biologically inert, so they’ll last indefinitely.
■ Structure and Materials
Class 160 tower design conforms to the latest edition of
the National Design Specification for Wood Construction (NDS)
published by the National Forest Products Association, as well
as CTI standards STD-114 and STD-103. Wind load criterion
is normally 30 pounds per square foot of projected area and
the design meets criteria for UBC Zone 1 seismic loading,
based on a maximum water temperature of 120°F.