VA 23 65 00-2010 COOLING TOWERS.pdf

1、02-10 23 65 00-1 SECTION 23 65 00 COOLING TOWERS SPEC WRITER NOTES: 1. DELETE BETWEEN /-/ if not applicable to project. Also delete any other item or paragraph not applicable in the section and renumber the paragraphs. Specify packaged cooling towers except in the rare cases where field assembled ty

2、pe has been selected. PART 1 - GENERAL 1.1 DESCRIPTION A. Packaged, /induced draft /forced draft /open circuit cooling tower/ closed circuit fluid cooler/complete with fill, fan, /inlet louvers /and associated accessories and equipment. 1.2 RELATED WORK A. Section 03 30 00, CAST IN PLACE CONCRETE: R

3、equirements for concrete inertia bases. /B. Seismic Restraint for Equipment: Section 13 05 41, SEISMIC RESTRAINT REQUIREMENTS FOR NON-STRUCTURAL COMPONENTS./ C. Section 23 05 11, COMMON WORK RESULTS FOR HVAC and STEAM GENERATION: General mechanical requirements and items, which are common to more th

4、an one item. D. Section 23 05 12, GENERAL MOTOR REQUIREMENTS FOR HVAC and STEAM GENERATION EQUIPMENT. E. Section 23 05 41, NOISE and VIBRATION CONTROL FOR HVAC PIPING and EQUIPMENT: Requirements for vibration isolation. F. Section 23 21 13, HYDRONIC PIPING: Requirements for water piping and fittings

5、. G. Section 23 25 00, HVAC WATER TREATMENT: Requirements for condenser water treatment. H. Section 23 31 00, HVAC DUCTS and CASINGS: Requirements for sheet metal ductwork. I. Section 26 29 11, LOW-VOLTAGE MOTOR STARTERS. 1.3 QUALITY ASSURANCE A. Refer to Article, QUALITY ASSURANCE, in specification

6、 Section 23 05 11, COMMON WORK RESULTS FOR HVAC and STEAM GENERATION. B. Design Criteria: 1. Design to withstand _Pa (_ psf) wind load. 2. Free water drift loss shall not be greater than five hundredths of one percent (0.005) of the water circulated to tower. Provided by IHSNot for ResaleNo reproduc

7、tion or networking permitted without license from IHS-,-,-02-10 23 65 00-2 SPEC WRITER NOTE: Specify dB(A) level based on the project specific acoustic analysis and local ordinance. 3. Sound levels at 1.5 meters (5 feet) and 17 meters (55 feet) in any direction from the tower shall not exceed _dB (A

8、) and _dB (A), respectively. Select “low Noise” model cooling towers, where available. Provide sound attenuators if necessary to meet the noise criteria. C. Performance Criteria: 1. Manufacturer shall certify that performance of cooling towers will meet contract requirements, stating entering air we

9、t bulb temperature, entering and leaving condenser water temperatures, water flow rates, fan kW (horsepower) /and pump head at base of tower/. Certification shall be made at the time of submittal. SPEC WRITER NOTE: CTI certification under Standard 201 applies only to selections with entering water t

10、emperature of 51.7 degrees C (125 degrees F) or less, temperature ranges of 2.2 degrees C (4 degrees F) or more, temperature approaches of 2.8 degrees C (5 degrees F) or more, and wet bulb between 15.5 degrees C to 29.5 degrees C (60 degrees F to 85 degrees F). 2. Cooling Technology Institute (CTI)

11、Certified Towers: These towers shall have been tested, rated, and certified in accordance with Cooling Technology Institute (CTI) Standard 201, and shall bear the CTI certification label, and shall be listed in the CTI directory of certified cooling towers. 3. The alignment and balancing of the fans

12、, motors and drive shaft as installed shall operate within the vibration tolerance specified in specification Section 23 05 41, NOISE and VIBRATION CONTROL FOR HVAC PIPING and EQUIPMENT. 1.4 SUBMITTALS A. Submit in accordance with specification Section 01 33 23, SHOP DRAWINGS, PRODUCT DATA, and SAMP

13、LES. B. Shop Drawings 1. Sufficient information, clearly presented, shall be included to determine compliance with drawings and specifications. 2. Include rated capacities, pressure drop, fan performance and rating curves, dimensions, weights, mounting details, front view, side view, equipment and d

14、evice arrangement. 3. Include electrical rating, detail wiring for power, signals and controls. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-02-10 23 65 00-3 /4. Pump characteristic curve for the closed circuit fluid cooler. / 5. Sound curves and

15、characteristics of sound attenuators if required to meet the noise criteria. SPEC WRITER NOTE: If the scope of work involves, total building commissioning, coordinate all documentation requirements with the commissioning efforts. C. Certification: 1. Submit four copies of performance curves, for CTI

16、 certified cooling towers, showing compliance with actual conditions specified, to the Resident Engineer two weeks prior to delivery of the equipment. 2. Two weeks prior to final inspection, submit four copies of the following to the Resident Engineer: SPEC WRITER NOTE: Specify the seismic design ca

17、tegory for the project so the cooling tower manufacturers can check/design seismic strength of their equipment. Delete the following paragraph if the seismic design category is A or B. a. Certification from the manufacturer that the cooling tower(s), accessories, and components are suitable for seis

18、mic design category _ installations and that the unit will be fully operational after the seismic event at the project site. b. Certification by the manufacturer that the cooling towers conform to the requirements of the drawings and specifications. c. Certification by the Contractor that the coolin

19、g towers have been installed, adjusted, and tested. 1.5 APPLICABLE PUBLICATIONS A. The publications listed below form a part of this specification to the extent referenced. The publications are referenced in the text by the basic designation only. B. American National Standard Institute (ANSI/ASSE)

20、A10.18-2007 Safety Requirements for Temporary Floors, Holes, Wall Openings, Stairways and Other Unprotected Edges in Construction and Demolition Operations C. American Society of Mechanical Engineers (ASME): PTC 23-03 Performance Test Codes on Atmospheric Water Cooling Equipment D. American Society

21、for Testing Materials (ASTM): A385-08 Standard Practice for Providing High-Quality Zinc Coatings (Hot-Dip) B117-07a . Standard Practice for Operating Salt Spray (Fog) Apparatus Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-02-10 23 65 00-4 B209-07

22、Standard Specification for Aluminum and Aluminum-Alloy Sheet and Plate E84-08a Standard Test Method for Surface Burning Characteristics of Building Materials E. Cooling Technology Institute (CTI): ATC-105-00 . Acceptance Test Code for Water-Cooling Towers (CTI Code Tower Standard Specifications) ATC

23、-105S-Rev. July 2004 Acceptance Test Code for Closed Circuit Cooling Towers (CTI Code Tower Standard Specifications) 201-02 (Rev. 04) . Standard for Certification of Water Cooling Tower Thermal Performance (CTI Code Tower Standard Specifications) F. National Electrical Manufacturers Association (NEM

24、A): MG 1-2006 Includes . Motors and Generators (ANSI) 250-03 . Enclosures for Electrical Equipment (1000 Volts Maximum) G. National Fire Protection Association (NFPA): 70-08 National Electrical Code PART 2 - PRODUCTS SPEC WRITER NOTE: Induced draft open circuit cooling towers should be used on a maj

25、ority of projects. In general, cross-flow type shall be used, where winter operation is required, specify counter-flow type. 2.1 INDUCED DRAFT OPEN CIRCUIT COOLING TOWER: A. Cooling tower shall be a factory assembled, induced draft, /cross-flow /counter-flow / type with a vertical discharge configur

26、ation. DESIGNER NOTE: Use stainless steel for all principal panels and structural elements, hot and cold water basins, fan deck, etc. for the High-Humidity locations listed in the VA HVAC Design Manual B. Casing: Heavy gage (minimum 16 gage)/ Galvanized Steel/ Stainless Steel / Fiberglass Reinforced

27、 Plastic (FRP) with UV inhibitors. / /1. Galvanized Steel: Hot-dip galvanized steel complying with ASTM A653/A653M, and having G235 (Z700) coating. / /2. Stainless Steel: ASTM A666, Type 304. / /3. Fiberglass Reinforced Plastic: FRP with maximum flame spread rating of five according to ASTM E84 and

28、with UV inhibitors. / 4. Fasteners: Zinc or cadmium coated bolts or tapping screws for assembly. Use stainless steel washers with neoprene backing where required for preventing leaks. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-02-10 23 65 00-5 5

29、. Joints and Seams: Sealed watertight. 6. Welded connections: Continuous and watertight. C. Framing: /Rolled structural steel shapes, hot-dip galvanized after fabrication or structural shapes cold formed from galvanized steel sheets or plates, complying with ASTM A653/A653M, and having G235 (Z700) c

30、oating. /Rolled or formed structural stainless steel conforming to ASTM A666, Type 304. / D. Louvers: 1. Spaced to minimize air resistance and prevent splash out. Louver materials shall be similar to the casings or may be polyvinyl chloride (PVC) if formed integral with the fill material. /2. 25 mm

31、(1 inch) inlet screen, hot dipped / galvanized steel or copper / stainless steel. / Attach the screen securely to air intakes. E. Fill: / PVC / FRP / resistant to rot, decay and biological attack; with a maximum flame spread rating of five per ASTM E84 and fabricated, formed and installed by manufac

32、turer to ensure that water breaks up into droplets. F. Drift Eliminators: Same as fill material. Effectively trap water droplets entrained in discharge air stream and limit drift loss to less than 0.005 percent of the total water circulated. Sections shall be assembled into easily removable racks of

33、 the same material as the casing. Eliminators can be PVC neoprene honeycomb type. SPEC WRITER NOTE: Eliminate the combustible materials when cooling tower is located 12 meters (40 feet) or closer to hazards such as chimneys, and incinerators, or when roof mounted. G. Hot Water Distribution System: O

34、pen basin, flume and troughs, or a pipe system with nozzles spaced for even distribution of water over fill material. Provide access door. System shall be self-draining and non-clogging. Spray nozzles, if used, shall be cleanable stainless steel, bronze or high impact plastic, non-clog, removable ty

35、pe properly spaced for even distribution. Provide cover for entire nozzle area or flume/trough area. / Provide manufacturers standard pre-strainer assembly and butterfly or globe valve, for cross flow tower, to balance the water flow to each basin. / H. Cold Water Collection Basin: Heavy gauge, zinc

36、-coated or hot-dip galvanized steel, same as the casing / stainless steel / FRP with UV inhibitors /. Overflow, drain not less than DN (Deutsches Normung) 50 (NPS (Nominal Pipe Size) 2), and a 304 stainless steel strainer assembly with openings smaller than nozzle orifices and with built-in vortex P

37、rovided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-02-10 23 65 00-6 baffling to prevent cavitation and air entrainment in the water basin circulating pump. I. Accessories: Make-up water, overflow and drain connections/; Equalizer connection (multiple coo

38、ling tower systems)/; Flume plate between adjacent cells (multi-cell units only)/. SPEC WRITER NOTE: On large multiple tower systems, on small systems with a single tower 50 tons or larger, or on systems requiring remote level indication/alarm capability, provide electronic level control. Locate the

39、 sensor in the equalization line on multiple tower systems. J. Collection Basin Water Level Control: / Mechanically operated bronze adjustable make-up water float valve. / Electronic operated with slow closing 120V solenoid valve and NEMA MG 1, Type 4x enclosure. Solid state controls with stainless

40、steel electrode probes and relays factory wired to a terminal strip to provide control of makeup valve, low and high level alarms and output for shutoff of pump on low level/. K. Fans: Heavy duty axial flow type, /belt/gear/ driven and balanced at the factory after assembly, with /cast aluminum or a

41、luminum alloy /FRP / blades. Fans shall be driven by / single speed / variable speed / motor. The fan drive and moving parts shall be completely enclosed by removable hot-dip galvanized screens and panels complying with OSHA regulations. Fan shaft bearings of the self aligning, grease-lubricated bal

42、l or roller bearings with moisture proof seals and premium, moisture-resistant grease suitable for temperatures between minus 29 and 149 degrees C (minus 20 and plus 300 degrees F). Bearings designed for an L-10 life of / 40,000 / 50,000 / hours and with extended lubrication lines to an easily acces

43、sible location outside of the wet air stream. Provide access doors for inspection and cleaning. L. Motors and drives: 1. The alignment and balancing of the fans, motors and drive shaft as installed shall operate within the vibration limits specified in specification Section 23 05 41, NOISE and VIBRA

44、TION CONTROL FOR HVAC PIPING and EQUIPMENT. 2. In addition to the requirements of specification Section 23 05 11, COMMON WORK RESULTS FOR HVAC and STEAM GENERATION, the following shall apply: a. Motors: Totally enclosed or epoxy encapsulated NEMA MG 1. Protect fan, bearings, and appurtenances from d

45、amage by weather, corrosion, water spray and grit. Provide motors with severe duty rating with the rotor and stator protected with corrosion-Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-02-10 23 65 00-7 inhibiting epoxy resin, double shielded, vac

46、uum-degassed bearings lubricated with premium moisture-resistant grease suitable for temperatures between minus 29 and plus 149 degrees C (minus 20 and plus 300 degrees F), and an internal heater automatically energized when motor is de-energized. Provide an adjustable motor base or other suitable p

47、rovision for adjusting belt tension. b. Fans for towers of 350 kW (100 tons) and less shall be belt driven. For towers larger than 350 kW (100 tons), fan shall be driven through a gear reducer, or driven by a V belt. 1) Gear reducer drive: Specially designed for cooling tower operation, with dynamic

48、ally balanced drive shaft assembly or shock absorbent flexible coupling requiring no lubrication, cast iron case with readily accessible oil drum and fill, and self-contained oil reservoir sealed against water entrance. 2) V Belt Drive: Fan shall be driven by a one-piece, multi-groove, neoprene/poly

49、ester belt, where this is the manufacturers standard. Belt drives shall be “V“ type as specified in specification Section 23 05 11, COMMON WORK RESULTS FOR HVAC and STEAM GENERATION. Belt driven fan and motor shafts shall have taper-lock sheaves fabricated from corrosion resistant material. SPEC WRITER NOTE: Coordinate motor and starter requi