SECTION FIELD ERECTED INDUCED DRAFT COOLING TOWER

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1 PART 1 GENERAL 1.1 RELATED DOCUMENTS A. Drawings and general provisions of the contract including general and supplementary conditions and specifications section apply to this section. B. Related Sections: The following sections contain requirements that relate to this section: 1. Section Hydronic Piping. 2. Section Hydronic Pumps. 3. Section HVAC Water Treatment. 4. Section Domestic Water Piping. 5. Section Domestic Water Piping Specialties. 6. Section Sanitary Waste and Vent Piping. 7. Section HVAC Insulation. 8. Section Mechanical Identification. 9. Section Motors and Variable Frequency Drives. 1.2 SUMMARY A. Cooling tower fill, distribution piping, drift eliminators and fan motor (concrete cooling tower structure). 1.3 REFERENCES A. ASME PTC 23 Atmospheric Water Cooling Equipment B. Cooling Tower Institute (CTI) ATC 105 Acceptance Test Code for Water Cooling Towers. C. Cooling Tower Institute (CTI) - Certification Standard STD SUBMITTALS A. Submit product data indicating rated capacities, dimensions, weights and point loadings, accessories, required clearances, electrical requirements and wiring diagrams, and location and size of field connections. B. Submit manufacturer s installation instructions. 1.5 OPERATION AND MAINTENANCE DATA A. Include start-up instructions, maintenance data, parts lists, controls, and accessories. 1.6 DELIVERY, STORAGE AND HANDLING A. Field assemble entire unit. Contractor shall field verify access to new tower enclosure prior to bid. Page 1 of 5

2 B. Comply with manufacturer s installation for rigging, unloading and transporting material. 1.7 WARRANTY A. Warranty: Include coverage for cooling tower package for one year from Date of Substantial Completion. PART 2 PRODUCTS 2.1 MANUFACTURERS A. Any of the following manufacturers may be used in the base bid. 1. Marley Cooling Technologies. 2. Tower Engineering, Inc. 2.2 GENERAL A. Provide material equipment and appurtenances required for a complete counter-flow, induced draft cooling tower assembly as detailed and scheduled on the drawings. The cooling tower shall include fill, fill support lintels, drift eliminators, fan assemblies, speed reducers, fan drives, water distribution system and all other materials and parts required to make the cooling tower complete. B. It is the intention of this specification to cover the basin construction requirements for the following type of cooling tower and provide a fireproof, permanent type cooling tower having aesthetics and life expectancy in keeping with the total project concept, one with full thermal efficiency throughout its life to afford minimum operating costs and minimum maintenance expense. C. The cooling tower furnished shall be a regularly cataloged product of a Cooling Tower Manufacturer who has produced towers which have seen at least ten (10) years of satisfactory service using the manufacturer and type of fill material and other components proposed for this project. Under no circumstances will wood, plastic, metal, cement asbestos or asbestos fill material be considered. D. Cooling tower cell shall cool 6,000 GPM of water from 95 F HWT to 85 F CWT when operating at the design inlet wet bulb temperature of 77.6 F. E. Upon completion, the Tower Manufacturer shall issue a written guarantee, duly signed, covering the following components. Should any of these components fail during the specified time, they will be replaced F.O.B. Shipping Point. 1. The fill and fill support lintels shall be guaranteed against un-serviceability for a period of twenty-five (25) years. 2. The remaining internal components shall carry the Manufacturer s standard warranty of one (1) year of service or eighteen (18) months from the date of shipment, whichever is first. All warranties are predicated on installation, maintenance and operation in accordance with Page 2 of 5

3 the Tower Manufacturer s published instructions. The Tower Manufacturer s obligation under the warranty is limited to replacing or repairing all items F.O.B. Shipping Point. F. The cooling tower shall be constructed where indicated on the Drawings. The Cooling Tower Manufacturer shall take these space limitations into consideration for the various designs required, including water cooling capacity and performance, fan air handling and the motor brake horsepower requirements. 2.3 COMPONENTS A. Lintels The tile support lintels shall be fabricated from cast iron or corrugated fiberglass reinforced vinyl ester resin and shall be capable of withstanding a load of 400 lbs. per linear foot based on a 6 foot span with a safety factor of 3. The lintels shall be cut and installed to fit snug against the tower walls to minimize any shifting of tile during a seismic event. B. Tile Fill The fill shall be of multi-cell design set without mortar in a pattern and shall be of sufficient height to meet the performance specifications. The tile fill shall be hard burned clay with an average of 3% with no sample exceeding 4% water absorption such that it will pass a freeze-thaw conducted in accordance with ASTM C-67. Further, the tile fill shall have a minimum crushing strength of 2,000 psi over the gross area of the tile when the load is applied parallel to the cell(s) as tested in accordance with ASTM C-67. C. Drift Eliminators Cellular 3-pass PVC type, 10 mil minimum sheet thickness with 25 mil minimum PVC stiffeners, UV protected PVC type, capable of supporting weight of maintenance workers without damage to the top surface. Supports shall be of corrugated FRP structural shapes sufficiently sized and spaced to permit a loading of 50 lbs/ft 2 and shall be suspended from 5/16 inch diameter (minimum) brass or stainless steel rods connected to stainless steel embeds in the underside of the roof deck (see Section 3.1) Drift eliminators supported on the hot water distribution piping will not be permitted. Allowable drift shall be limited to 0.001% of circulating water flow. Mist eliminators shall have a flame spread rating of 15 or less when tested in accordance with ASTM E84. Provide a framed stainless steel access door for passage through eliminators to fill. Provide a 24-inch wide FRP grating maintenance walkway form access opening to the center of each cell and an HDG maintenance access form walkway to gearbox. D. Speed Reducers Shall match existing Amarillo units with speed reducer gears rated in accordance with practices of the American Gear Manufacturers Association using a Service Factor of 2.0 minimum for cooling tower services. These shall be in accordance with CTI STD-111. The gear reducers shall be of the spiral bevel type, double-reduction type. The gear reducer shall be bolted on a galvanized steel base plate and bolted and grouted to the structure. A vibration switch shall be supplied to protect the mechanical equipment against excessive damage due to a malfunction of the rotating members. The vibration switch shall be mounted near the gear reducer. The vibration switch shall automatically provide a 15 second time delay upon fan start-up to prevent false shutdown. The switch shall be a PMC Beta Model 440S. An oil level switch shall be provided by the Cooling Tower Manufacturer to provide protection against sudden loss of oil or low oil level in the gear reducer. Electrical connection and wiring of the vibration switch, and oil level switch in series with the control Page 3 of 5

4 circuit of the cooling tower motor magnetic starter shall be provided under Division 16. A stainless steel oil level sight glass, fill/drain line and vent line shall be installed terminating outside the fan stack. Drive shall be suitable for continuous operation at one-third maximum speed. E. Fan Assembly Shall match existing Hudson, 7-bladed fans. The complete fan assembly (the fan and mounting) shall be designed to give maximum fan efficiency and long life when handling saturated air at high velocities. The fan shall be of a multi-blade design. The fan blades shall be fiberglass reinforced resin system. F. Drive Connection The drive shaft shall be the full floating type with flexible couplings at both ends. The drive shaft shall be of composite design and shall eliminate the need for an intermediate pillow block bearing and shall be fitted on each end with flexible stainless steel plate type couplings. Each drive shaft coupling shall be provided with a galvanized steel guard to prevent damage to the surrounding equipment in case of shaft failure. G. Motor The motor shall be Premium efficiency, NEMA rated and shall be of the TEFC type with a Service Factor of 1.0 and with Class B insulation. The motor horsepower shall be of the next larger standard motor size than that calculated as required for the individual fan brake horsepower and shall be 3-phase, 60 Hertz, 460 Volt continuous duty type with normal starting torque. This motor shall be 100 horsepower, single-speed. Motor shall be Reliance brand XEX type. The fan drive motor and base plate shall be supplied and installed by the Cooling Tower Manufacturer, bolted and grouted to the structure after final adjustments. H. Distribution System Piping shall be schedule 40 PVC. The fittings and nozzles are PVC or ABS. The distribution system shall match the systems in the existing operational ceramic cooling tower cells, in design, layout, number of nozzles, type of nozzles, and required pump head, in order to allow for balancing of the five tower cells with the use of a common inlet header. The pump head, including static lift and dynamic head, shall not exceed 22-0 when measured from the interface flange located 6 below the top of the fill support beam up and through the nozzles. The distribution piping, including spray nozzles, pipe and fittings, shall be supplied complete to flange face located at a point 6 below the top of the fill support beam. I. Fan Deck The fan deck shall be constructed of poured-in-place monolithic concrete by the General Contractor, forming a rigid base for mounting the fan, speed reduction coupling/drive shaft and motor. Grout after final alignment. J. Exhaust Fan Stack The exhaust fan stack shall be constructed of poured-in-place monolithic concrete by the General Contractor. An aluminum fan screen shall be furnished by the tower manufacturer over the fan stack. K. Tower Access A hot dip galvanized steel access door hall be provided for roof deck access. Ladder rungs cast in concrete shall be provided by The General Contractor and coordinated with the Cooling Tower Manufacturer. PART 3 EXECUTION Page 4 of 5

5 3.1 INSTALLATION A. Install in accordance with manufacturer s instructions. B. Install tower on view structural supports. C. Connect condenser water piping with flanged connections to tower. 3.2 FIELD QUALITY CONTROL A. Test under actual operating conditions and verify specified performance. 3.3 MANUFACTURER S FIELD SERVICES A. Prepare and start systems under provisions of General Conditions. B. Inspect tower after installation after installation and submit written report prior to start-up, verifying installation is in accordance with specifications and manufacturer s recommendations. C. Train Owner s maintenance staff in tower operation and maintenance. Provide seven (7) days notice prior to schedule training. END OF SECTION Page 5 of 5