SPX Cooling Technologies Marley MD Design Loading, Construction, Mechanical Equipment

Marley / MD CoolingTower / Specifications: Base

Specifications Specification Value

4.0Design Loading:

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4.1	The tower and its components shall be	■ The indicated design values are the minimum allowables under
	designed to withstand a wind load of	accepted design standards. They give you assurance that the cool-
	1.44kPa. The cooling tower shall be de-	ing tower can be shipped, handled, hoisted—and ultimately oper-
	signed to withstand shipping and hoist-	ated in a normal cooling tower environment. Most MD models will
	ing loads of 2g horizontal or 3g vertical.	withstand significantly higher wind and seismic loads. If your geo-
	Guardrails, where specified shall be	graphic location dictates higher wind load or seismic load values,
	capable of withstanding a 890N con-	please make the appropriate changes, after discussion with your
	centrated live load in any direction and	Marley sales representative.
	shall be designed in accordance with
	OSHA guidelines.

5.0Construction:

5.1	Except where otherwise specified,	■ In the history of cooling towers, no other coating for carbon steel
	all components of the cooling tower	has exhibited the success and longevity of galvanization in expo-
	shall be fabricated of heavy-gauge	sure to the normal cooling tower water quality defined at left. No
	steel, protected against corrosion by	paints or electrostatically-applied coatings, however exotic they
	EN10142:2000 grade Z600 galvaniz-	may be, can approach galvanization's history of success.
	ing. After passivation of the galvanized
	steel (8 weeks at pH 7-8, and calcium	If extended longevity of the cooling tower is required—or unusually
	hardness and alkalinity at 100-300	harsh operating conditions are expected—consider specifying stain-
	mg/L each), the cooling tower shall be	less steel as either the base construction material, or the material
	capable of withstanding water having a	utilized for specific components of your choice. See Stainless Steel
	pH of 6.5 to 9.0; a chloride content up	Options on page 16.
	to 500 mg/L as NaCl (300 mg/L as Cl-);
	a sulfate content (as SO4) up to 250
	mg/L; a calcium content (as CaCO3)
	up to 500 mg/L; silica (as SiO2) up to
	150 mg/L; and design operating ranges
	up to 10°C. The circulating water shall
	contain no oil, grease, fatty acids, or
	organic solvents.

5.2The specifications, as written, are intended to indicate those materials that will be capable of withstanding the above water quality in continuing service, as well as the loads described in paragraph 4.1. They are to be regard- ed as minimum requirements. Where component materials unique to indi- vidual tower designs are not specified, the manufacturers shall take the above water quality and load carrying capabili- ties into account in the selection of their materials of manufacture.

6.0Mechanical Equipment:

6.1	Fan(s) shall be propeller-type, incorpo-	■ Propeller-type fans require only half the operating hp of blower-type
	rating heavy aluminum alloy blades and	fans. However, they should be readily adjustable to permit compen-
	electrogalvanized hubs. Blades shall be	sation for jobsite conditions. The fans of one manufacturer require
	individually adjustable and both stati-	the purchase of special positioners for each increment of fan blade
	cally and dynamically balanced. Fan(s)	pitch. The Marley Power Belt drive system features all-aluminum
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