Project 9D03254 - Supply of Cooling Tower

Procuring Entity:
University of Western Ontario (Western)
Procurement Services
1151 Richmond Street
London, Ontario, Canada, N6A 3K7

Contact:
Heather Hyde
hhyde@uwo.ca

Procurement Method:
Open tender whereby all interested Suppliers may submit a Proposal.

Description:
This RFQ is an invitation to submit offers for the supply of a new Cooling Tower. 

COOLING TOWER TECHNICAL SPECIFICATIONS

1. General
   1. The following specification is based on an SPX/Marley Model NC8409U-1 two air inlet, induced draft, crossflow type, factory assembled, 3 cell cooling tower with vertical air discharge.  The cooling tower individual cells shall be factory assembled, except for accessories (such as ladders, service platforms, flume boxes, fan blades and guardrails) and controls equipment, which can be shipped loose for field installation by mechanical contractor. The cold water basins shall be interconnected with flume boxes, designed and sized to maintain equal water level in all three cells.

2. Thermal Performance
   1. The cooling tower shall be able to cool 7,050 USgpm of water from 95°F to 85°F at an ambient wet bulb temperature of 78°F, or 2,350 tons at AHRI standard conditions. The thermal performances shall be CTI certified, as per STD-201.

3. Material of Construction
   1. The cold water basin shall be fully welded heavy gage 304 series stainless steel construction; the hot water distribution basin shall also be constructed of heavy gage 304 series stainless steel. The rest of the cooling tower panels and structural elements shall be made with G235 grade hot dipped galvanized steel.

4. Dimensions and Weight
   1. The overall cooling tower dimensions shall be between 40 and 48 feet long; 21 to 24 feet wide and between 11 and 14 feet high (not including fan cylinder extension). Furthermore, shipping weight of the complete tower shall be between 44,000 and 50,000 lbs.  Maximum operating weight shall be 105,000 lbs.

5. Structural Requirements
   1. The tower structure, anchorage and all its components shall be designed by licensed professional engineers registered in Ontario, employed by the manufacturer, per the Ontario Building Code to withstand a wind load of 30 psf, as well as the local earthquake loading requirements in the Ontario Building Code (OBC). The fan deck, hot-water basin covers and, where specified, maintenance platforms shall be designed for 60 psf live load or a 200 lb concentrated load. Guardrails, where specified, shall be capable of withstanding a 225 lb concentrated live load in any direction, and shall be designed in accordance with OHSA guidelines in Ontario and the OBC. The complete mechanical equipment assembly for each cell shall be supported by two horizontal steel beams that resist misalignment between the motor and the gear reducer drive system.

6. Water Distribution
   1. Each cell shall include a single bottom water connection with internal piping to each distribution basin; it must be designed and sized to maintain equal water level in both distribution basins. The connection pipe size shall be either 10 or 12 inches. Each distribution basin must feature either weirs or nozzle cups to enable proper and uniform water distribution (to the inlet fill area at reduced flow) at any flow ranging from 30% to 100% of nominal flow. Any tower part that the water touches in the water distribution system must be either 304 stainless steel or non-metallic. The hot water distribution basins shall also feature 304 stainless steel covers.

7. Water Outlet
   1. Each cell will feature a depressed sump complete with side outlet and strainer plate, all of which shall be made of 304 stainless steel. The connection pipe size shall be either 10 or 12 inches. Each cell will also feature a 4 inches combination overflow and drain pipe.

8. Water Make-Up Control
   1. No makeup water valve or any other water level control is required.

9. Heat Exchange Fill
   1. Fill shall be film type, thermoformed of PVC, with louvers and eliminators formed as part of each fill sheet. Fill shall be suspended from hot dip galvanized structural tubing supported from the tower structure, and shall be elevated above the floor of the cold-water basin to facilitate cleaning. Air inlet faces of the tower shall be free of water splash out.

10. Fans
    1. The fans shall be axial and blowing vertically upward, away from the tower. They shall be of the ultra-quiet design, each of the three fan generating a maximum overall sound power level of 93 dB, and a maximum overall sound pressure level at 50 feet distance of 60 dB for the air inlet and 64 dB for the fan discharge.

1. 2. The motor shall be a maximum of 50 HP for each cell. The motor shall be IEEE 841 type for very harsh service, including inverter duty rating. A fan cylinder extension shall be provided to totally enclose the ultra-quiet fan blades. The power transfer between the motor and the fan shall be with a transfer gearbox of the proper ratio. The gearbox casing shall be high quality grey iron covered with two coats of epoxy paint. All the bearings within the gearbox shall feature L10A life of at least 100 000 hours. The gears shall have fine mesh to promote quiet operation, and shall be AGMA quality class between 9 and 11. The mechanical equipment shall feature external lube lines. The motor to gearbox close coupling shall be a tire-type, single piece, flexible element design to accommodate frequent speed changes that are inherent with VFD applications.

11. Warranty
    1. The cooling tower including all mechanical equipment such as fan, gearbox, mechanical equipment support and fan motor shall be warranted against defects in materials and workmanship for a period of five (5) years from date of shipment.

12. Accessibility for Maintenance and Service
    1. There shall be large access doors on each side of each cell leading to an interior walkway, at least 30 inches wide, running the full length of each cell. There shall be an exterior service platform at each end of the tower to enable safe ingress/egress from the access doors.

1. 2. On one end of the cooling tower, there shall be two cased face ladders, complete with self-closing safety gates at the top, to access each side of the hot water distribution basins deck and the access door service platform. The ladders shall have proper extensions below the cooling tower cold water basin, which will be +/- 5 feet above roof level. The cooling tower shall also feature a full guard rail around its perimeter, complete with knee rails and toe boards. Finally, there shall be an interior service platform on each cell for servicing mechanical equipment. All of these accessories shall be designed according to OHSA standards in Ontario.

13. Vibration Switch
    1. A vibration limit switch in a NEMA 4X housing shall be supplied and installed on the mechanical equipment support. The purpose of this switch will be to interrupt control power voltage to a safety circuit in the event of excessive vibration causing the starter or VFD equipment to de-energize the motor. It shall be adjustable for sensitivity, and include a means to reset the switch.

14. Start-up and Site Visits
    1. The cooling tower manufacturer shall provide a technician to guide the mechanical contractor during the cooling tower hoisting, rigging and final installation of its accessories. Furthermore, a technician shall also be present during final start-up of the cooling tower and will also provide a half day training of the cooling tower maintenance and operation recommendations to University staff.

15. Delivery Schedule
    1. The new cooling tower will be delivered FOB on the truck at the job site. The new cooling tower will be required on site between March 15th 2020 and May 15th 2020; final delivery date during this period to be coordinated by the mechanical contractor.

16. Operation and Maintenance Manuals
    1. The manufacturer shall provide 1 paper copy and 1 digital copy of the cooling tower operation and maintenance manuals, and for any part or accessories not covered in the tower O&M manuals

17. Equivalent Equipment
    1. The following manufacturers of the above equipment will be considered approved alternatives, however to be considered equal, the proposed cooling tower from these equivalent manufacturers must fully comply with the technical specifications.

1. Bid Form
2. General Arrangement Drawings