SPX Cooling Technologies Marley Sigma Steel Specifications, Specification Value, 3.0Construction

Marley / Sigma Steel CoolingTower / Specifications: Base

Specifications Specification Value

14

3.0Construction:

3.1The tower shall be capable of with- standing water having a pH of 6.5 to 8.0; a chloride content (NaCl) up to 300 ppm; a sulfate content (SO4 ) up to

250 ppm; a calcium content (CaCO3) up to 500 ppm; silica (SiO2) up to

150 ppm; and design hot water tem- peratures up to 120°F. The circulating water shall contain no oil, grease, fatty acids, or organic solvents.

3.2The structural framework of the tower, as well as all basins and decking, shall be of heavy gauge cold-formed steel and/or mill shapes, hot-dip galvanized after fabrication to a deposition of at least 2.25 ounces of zinc per square foot.

3.3Column lines shall be on no greater than 4' longitudinal centers, and the base of all columns shall be firmly anchored. Basic design criteria shall be 30 psf wind load and 5%g seismic load. Framing joints shall be made with 1⁄2" diameter and larger Series 300 stainless steel machine bolts, nuts and washers.

3.4Towers of more than one cell shall include galvanized internal partitions to separate the fan plenums, and a hinged access door shall be provided in each partition for freedom of access throughout the tower.

■The limiting water quality values indicated are those which are accept- able for the normal materials of construction specified. If water of more aggressive quality is anticipated, consider specifying a stainless steel Sigma tower. See page 27.

■Hot-dip galvanizing after fabrication assures that all steel surfaces will be heavily coated with zinc. All shearing, bending, drilling, punching, etc. will have been completed prior to galvanization.

■Multicell towers must have plenum partitions between cells. Otherwise, air will be induced downward through an inoperative fan, bypassing the fill entirely. Without these partitions, part-load or off-season opera- tion of the tower would be completely unsatisfactory.