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Minimum Maintenance and Service Life
The conditions within a cooling tower are complex. There are several factors that play a role in determining the frequency and type of maintenance a cooling tower requires to operate efficiently. The selection of material that will be used to construct a cooling tower, the water and chemicals used in a cooling tower, and the surrounding environment will affect the maintenance and service life of a cooling tower.

Cooling-tower-frame-structure recommendations for minimum maintenance and extended service life include:

• Concrete.
• Concrete and fiberglass.
• Fiberglass.

Metal recommendations to eliminate or reduce corrosion include:

• Structure hardware and anchor plates—304- or 316-grade stainless steel, silicon bronze, or Monel.
• Drive frame (torque tube)—hot-dip galvanized (HDG), HDG and epoxy, or 304-grade stainless steel.
• Fan hub—HDG or HDG and epoxy.
• Fan-blade hardware—304- or 316-grade stainless steel or Monel.
• Fan-stack hardware—304- or 316-grade stainless steel or silicon bronze.
• Motor and gearbox hardware—304- or 316-grade stainless steel or Monel.

Conclusion
Taking the time to identify the demands required for a cooling-tower system to operate efficiently is a vital part of the cooling-tower-design process. There are certain requirements with which all cooling towers must comply, but critical-demand cooling towers have special requisites that must be addressed. The design process is the logical time to identify and incorporate the necessary elements for the construction of a cooling-tower system that provides comfort and longevity.

Bibliography
ASTM. Standard test methods for fire tests of building construction and materials. ASTM E119. West Conshohocken, PA: ASTM International.
International Code Council. (2006). International building code 2006. Washington, DC: International Code Council. NFPA. (2005). Standard water-cooling towers. NFPA 214. Quincy, MA: National Fire Protection Agency.

Did you find this article useful? Send comments and suggestions to Associate Editor Megan Spencer at megan.spencer@penton.com.

President of Composite Cooling Solutions LP (CCS), David M. (Mike) Bickerstaff has three decades of cooling-tower-industry experience, including the erection of cooling towers and air-cooled condensers for HVAC, process, and power applications. A construction-management strategist, he has held senior construction-management roles with Marley Cooling Technologies and Ceramic Cooling Tower Co. The vice president of marketing, building trades, and light industrial for CCS and the president of Bowman Engineering & Equipment Co., Frank J. Bowman Jr. has more than four decades of sales- and marketing-management experience in the cooling-tower industry. He has served as vice president of international marketing for Baltimore Aircoil and director of marketing for Ceramic Cooling Tower Co.