NIT No. 35/EE(E)BM-I/2026-27

Dismantling of the existing following type tube type axial flow fan installed at the AHU rooms of Talkatora Stadium & Terrace of the NIA Building and, including disconnecting the electrical supply, removing all associated nuts, bolts, supports, flexible connections, vibration isolators and accessories, dismantling the existing fan assembly with the help of chain pulley block, heavy labour, lifting tackles and all necessary tools and tackles, carefully lowering and removing the fan from its installed position without causing damage to the existing building structure or adjoining services, shifting the dismantled material to the designated location as directed by the Engineer-in-Charge, and disposing of unserviceable material as per departmental instructions. Thereafter, supplying, installation, testing and commissioning of following capacity reversible type tube axial flow fan having minimum static pressure of 40-45 mmWG, complete with Universal Mounting Feet, Bolted Inspection Door, Inlet & Outlet Flexible Duct Connections, Spring Base Isolators and all accessories. The fan casing shall be of continuously welded galvanized steel with integral punched inlet and outlet flanges to prevent air leakage. The propeller shall be of cast aluminium airfoil blades with cast aluminium hub having manually adjustable blade pitch. Housing components shall be a combination of pre-galvanized and hot-dip galvanized steel. The fan shall be provided with bird screens on both inlet and outlet sides and shall be suitable for fire-rated applications (250°C for 2 hours / 300°C for 1 hour). The motor shall be IE-2 efficiency or better, 1440–1450 RPM, suitable for 415V, 3 Phase, 50 Hz AC supply, IP55 protection, Class F or higher insulation, Class H temperature rating, VFD compatible, spark-resistant construction as per AMCA Type C, Explosion Proof (Gas Group IIB, Temperature Class T4) with epoxy-coated finish, having adequate kW rating to meet the specified performance. The work shall include all foundation bolts, mounting arrangements, anti-vibration pads, alignment, grouting wherever required, electrical connections, earthing, testing, balancing, commissioning and all incidental works complete in all respects as required and as directed by the Engineer-in-Charge. a) 22000 CFM /37378 CMH (Talkatora Stadium)

b) 7000 CFM/ 11893 CMH (NIA Building)

c) 5000 CFM /8495 CMH (NIA Building )

Dismantling of the existing rusted, worn-out G.I. ducting of required sizes, including carefully disconnecting the duct sections from the existing AHU/fan, removing all hangers, supports, nuts, bolts, flanges, cleats, angles, dampers, insulation (wherever applicable) and other accessories with the help of heavy labour, ladders, scaffolding, tools and tackles, lowering the dismantled ducting safely without causing damage to the existing building structure or adjoining services, shifting the dismantled material to the designated location as directed by the Engineer-in-Charge, and disposing of unserviceable material as per departmental instructions. Thereafter, supplying, fabrication, installation, testing and commissioning of new G.I. ducting fabricated from 22 SWG galvanized iron sheets of approved make, conforming to IS standards, including all necessary flanges, cleats, G.I. angle frames, nuts, bolts, gaskets, sealant, stiffeners, hangers, threaded rods, M.S. supports, anchor fasteners, anti-rust primer and synthetic enamel paint on M.S. supports, complete as per approved drawings and site requirements. The work shall include cutting, bending, folding, riveting, sealing of joints to make the duct air-tight, providing all suspension arrangements, erection with the help of ladders/scaffolding, testing for air leakage, commissioning, and making good all disturbed portions, complete in all respects as required and as directed by the Engineer-in-Charge

Dismantling of the existing worn-out M.S. supporting structure provided for the tube axial flow fan installed on the terrace of the NIA Building including cutting, dismantling and removing the existing rusted M.S. channels, angles, base frame, supports, foundation bolts and all associated members with the help of gas cutting equipment, welding machine, grinders, heavy labour, lifting tackles and all necessary tools and plants, carefully removing the dismantled material without causing damage to the existing RCC slab, or adjoining services, shifting the dismantled material to the designated location as directed by the Engineer-in-Charge and disposing of unserviceable material as per departmental instructions. Thereafter, providing, fabricating, supplying, installing, testing and commissioning of a new heavy-duty M.S. supporting structure fabricated from 75 mm × 40mmx 4 mm M.S. C-Channels and 50 mm × 50 mm × 4 mm thick M.S. Angles as per site requirements and load calculations for supporting the following Tube Axial Flow Fan. The framework shall consist of base frame, cross members, vertical supports, bracing members, gusset plates and all necessary structural members to withstand continuous vibration and outdoor weather conditions. The work shall include cutting, drilling, welding, grinding, alignment, providing base plates, anchor fasteners/foundation bolts, anti-vibration mounting arrangement, stiffeners, complete structural framework, and all necessary hardware including nuts, bolts and washers. The entire structure shall be cleaned thoroughly and treated with one coat of zinc-rich metal primer followed by two coats of epoxy/polyurethane weather-resistant paint, suitable for installations having direct exposure to sunlight, rain and corrosive atmospheric conditions a) 7000 CFM/ 11893 CMH (NIA Building)

b) 5000 CFM /8495 CMH (NIA Building )

Dismantling of the existing non-functional motorized fire damper in 22000 CFM axial flow fan installed in the supply air duct/main branch or return air path, including disconnecting the electrical supply and control wiring, removing the existing actuator, damper assembly, sleeves, flanges, nuts, bolts, supports, brackets and all associated accessories, carefully dismantling the damper from the duct line with the help of necessary tools, ladders/scaffolding and skilled labour without causing damage to the existing ducting, walls or adjoining services, shifting the dismantled material to the designated location as directed by the Engineer-in-Charge and disposing of Unserviceable material as per departmental instructions. Thereafter, supplying, fixing, testing and commissioning of new motorized fire dampers of minimum 120 minutes fire rating, suitable for installation in supply air ducts/ main branches and return air paths, of required sizes, complete with control wiring. The fire damper shall be motorized with an inbuilt spring return mechanism to ensure automatic closing of the damper in the event of power failure and automatic reopening upon restoration of power. The spring return mechanism shall be integral to the actuator and shall not be externally mounted. The damper shall also close automatically upon receipt of a fire signal from the Fire Alarm System and shall comply with the relevant IS standards, NBC guidelines and project specifications. The item shall include galvanized steel sleeves, flanges, mounting frames, support angles, anchor fasteners, nuts, bolts, wiring from the nearest junction box/control panel, glands, lugs, ferrules, earthing, fire-resistant sealant around wall penetrations, complete in all respects as required and as directed by the Engineer-in-Charge.

Credit for retaining the old axial fans, ducting & MS structure