Replacement of outlived Cooling Tower in MSB building and Library Building, IIT Delhi

Amount

Replacement of existing cooling tower by supplying, installing, testing and commissioning of Induced Draft Counter Flow Cooling Tower with Fibre Reinforced Plastic (FRP) casing in square / rectangular shape and with FRP basin matching with the shape of the casing on the existing framework (including suitable modifications as required) as per following Specifications: - a] RATING: The cooling tower shall be rated for not less than 6,72,000 Kcal / Hour heat rejection capacity. b] RANGE: The Cooling tower shall be designed to cool the requisite quantity of water through 4.2 degree Centigrade or more against the prevailing wet bulb temperature. c] WET BULB APPROACH: The cooling tower shall be for a wet bulb approach of not more than 2.77 degree Centigrade. d] FLOW RATE: The water flow rate through the cooling tower shall be not less than 125 CMH (cubic metre per hour) e] MULTI CELL DESIGN: The induced draft cooling tower shall be of more cells f] DRIVE MOTOR : The fan drive shall be from a three phase induction motor of efficiency class not less than IE3 as per IS 12615, either direct or through a spiral gear work. The entire drive arrangement shall be designed for a minimum noise and it shall be rigidly supported to the tower structure. Fibreglass Reinforced Plastic (FRP) Cooling tower shall be as per following: i] The structural framework of the cooling tower including all members shall be designed for the load encountered during the normal operation of the cooling tower and its maintenance. The structure shall be rugged and rigid to prevent distortion and shall include tie arrangements as may be necessary. ii] The air intake shall be from openings all along the sides. These openings shall be covered with hot dip galvanised expanded metal mesh screens. iii] The basin shall have a holding capacity adequate for operation for at least 30 minutes without addition of make-up water to the basin. The construction should be such as to eliminate the danger of drawing air into the pump when operating with minimum water in the basin. iv] The basin fittings shall include the following: - a) Bottom /side outlet, b) Drain connection with valve, c) Ball type automatic make-up connection with valve (float valve), d) Overflow connection, e) Bleed off with valve, from inlet header to overflow pipe. v] The supporting framework for the tower casing and the water basin shall be made of hot dip galvanised steel and it shall be further protected with epoxy painting. vi] The filling shall be of PVC. Thickness of PVC fills shall not be less than 0.2mm. These shall be of such construction as to provide low air resistance, large wetted surface for a high heat transfer efficiency, and easy replace ability.vii] The water distribution may be either through self-rotating or fixed type sprinklers or through balancing, sub balancing and spreader troughs (unpressurised system) ― "open gravity type with polypropylene nozzle" ensuring uniform water loading and distribution of water over the fill. All pipes and fittings shall be of PVC. The sprinklers shall operate from the residual velocity head at the headers. Due care shall be taken with regard to corrosive effects and maintainability in the design of the water distribution system. viii] Drift eliminators of PVC shall be provided for maximum removal of entrained water droplets. The spacers and tie rods used shall be of plastic material. ix] The fan shall be multi-blade axial flow type, made of aluminium alloy. The fan assembly shall be statically and dynamically balanced. x] To ensure safety of personnel at the time of working on cooling tower a steel ladder shall be provided in such a manner and location as necessary to give safe and complete access to all the parts of the cooling tower requiring inspection or adjustments. The ladder shall be bolted to the tower at the top and grouted in masonry at the bottom end. xi] Not less than 6mm neoprene pads shall be placed between the tower and the girder for vibration isolation whereas directed by the Engineer-in-charge. Guy-wires of suitable sized shall be used to secure firmly to its base wherever necessary. xii] The cooling towers shall be supplied with the manufacturer’s standard finish painting. xiii] Second class brick work and cement mortar having one part cement & six parts sand shall be used for the masonry work. 12mm sand cement plaster shall be provided over the brickwork wherever necessary during installation work.

COMFORT SYSTEMS (BID ID -3161699)