PROVISION OF PRE FABRICATED PORTA CABIN FOR PR EQUIPMENT AT CG JETTY VISAKHAPATNAM UNDER GE (I) (CG) VIZAG

Supply and fixing Porta Cabins (MS Fabricated Container) of size (40' x 10' x 8.5') comprising with the following specifications :- TECHNICAL SPECIFICATION OF CABIN (A) Material Certification: All structural steel sections (RHS, SHS, ISMC, Angles) must be new, prime quality, and sourced from reputed mills (e.g., SAIL, JSW, Tata Steel) with relevant mill test certificates. Sections must be free from twists, bends, or any surface defects like laminations or pitting. (B) Bottom Frame (Base Structure): (a) Main Longitudinals & Cross Members: Fabricated from 100mm x 50mm x 3.2mm (minimum thickness) MS Rectangular Hollow Sections (RHS) . The main longitudinal members shall run the full 40ft length without any intermediate joints. Cross members shall be placed at a maximum center-to-center spacing of 600mm to provide adequate support for the flooring system. (b) Stiffening: The frame shall be further stiffened by welding 100mm x 50mm ISMC (Channel sections) and 60mm x 40mm MS square pipes in both directions. The number and placement of these stiffeners shall be based on a structural design calculation, ensuring that the floor can withstand a minimum uniformly distributed load (UDL) of [e.g., 250 kg/m²] and a concentrated load of [e.g., 150 kg] at any point. (c ) Corner Castings: Heavy-duty, fabricated or cast steel corner fittings (similar to shipping container standards) must be integrated at all eight corners. These are critical for lifting, stacking, and securing the cabin during transport and at the site.

(C) Top Frame (Roof Structure): (a)Main Members: Fabricated from 50mm x 50mm x 2.6mm (minimum thickness) MS Square Hollow Sections (SHS) . (b)Stiffening & Purlins: The roof frame must be stiffened longitudinally and transversely with a grid of 50mm x 50mm SHS and 25mm x 25mm SHS acting as purlins. The spacing of these purlins shall be designed to adequately support the roof sheeting and any live load during maintenance, with a maximum spacing of 700mm. The frame must be designed with a pre-determined camber (e.g., 1/200 of span) to compensate for dead load deflection. (D) Corner & Side Posts (Vertical Supports): (a)Corner Posts: Fabricated from high-strength 75mm x 75mm x 6mm MS Angle or a fabricated box section of equivalent strength. These are the primary load-bearing members for vertical loads from stacking and must be perfectly vertical and plumb. (b)Intermediate Posts: A minimum of 10 posts per cabin. These shall be fabricated from 65mm x 65mm MS Angle for door/window jambs and 50mm x 50mm SHS for wall stiffeners. All posts shall be precisely aligned and fully welded to both the top and bottom frames at their ends, creating a rigid box structure. (c) Base Plates: Each post shall be welded to a robust 150mm x 150mm x 10mm thick MS base plate, which is then continuously welded to the bottom frame, ensuring effective load transfer.

(E) Fabrication Quality: (a)Welding: All structural welds must be continuous and of high quality, performed by certified welders using appropriate electrodes (e.g., E7018). Slag must be removed, and welds should be visually inspected for uniformity, penetration, and freedom from cracks or undercuts. (b)Lifting Arrangements: Lifting hooks or lugs shall be specially designed and fabricated from high-tensile steel plate (minimum 20mm thick). They must be reinforced with gusset plates and welded directly to the main corner posts and top frame to safely withstand the dynamic loads during lifting operations. The design safety factor for lifting shall be a minimum of 4:1. (F) Finishing and Painting (Structural Steel) Surface Preparation (Blast Cleaning): The entire fabricated steel frame shall be thoroughly prepared by abrasive blast cleaning to a minimum standard of Sa 2.5 (Near-White Metal) as per ISO 8501-1. This removes all mill scale, rust, and foreign matter, creating a perfect profile for paint adhesion. Finish Coats: Two finishing coats of high-performance two-pack polyurethane (PU) enamel in the specified shade shall be applied. PU enamel offers superior gloss retention, UV resistance, and durability compared to synthetic enamel, which is critical for the external environment. The total dry film thickness (DFT) of the entire paint system shall be a minimum of 150-200 microns.

(G) Wall, Roof, and Flooring: Detailed Description (a) External Wall Cladding:• Material: 1.2mm (minimum base thickness) pre-painted Galvalume (Alu-Zinc) steel coil (Make: TATA JSW, or equivalent). Galvalume offers superior corrosion resistance compared to galvanized iron, especially in saline atmospheres. (b) Profile & Fixing: Sheets shall be roll-formed into a vertical ribbed profile (e.g., sinusoidal or trapezoidal) for added strength and aesthetic appeal. They shall be fixed to the side posts and frames using self-drilling, corrosion-resistant fasteners with EPDM bonded washers to ensure a water-tight seal. Flashings at corners and edges shall be made from matching material. (c) Internal Wall Paneling: Office Area: 8mm thick, high-density, moisture-resistant MDF (Make: Greenply MR MDF or equivalent). The boards must be fixed over the insulation layer to a sub-frame, ensuring a smooth, flush finish. (H) Roofing System: External Sheet: 1.2mm thick pre-painted Galvalume high-rib profile sheet (e.g., Trapezoidal profile with a rib height > 35mm). The high ribs provide excellent water-carrying capacity, allowing for minimal slope. Sheets shall be laid with side and end laps of at least one full rib and 150mm respectively, sealed with butyl tape, and fixed with appropriate fasteners. A ridge cap shall be provided for a watertight finish. (J) Insulation: As per clause 4.5. False Ceiling: 8mm thick, high-density, moisture-resistant MDF. The boards shall be precisely cut and fixed to an aluminium grid suspension system. The entire ceiling shall be perfectly level, and all perimeter edges shall be finished with a decorative aluminium moulding. Provision for recessed/ surface mounted LED lights must be accurately cut out.

(K) Flooring System: •Sub-floor: 18mm thick high-density, waterproof cement particle board (CPB) . CPB is preferred over standard cement fiber board for its superior screw-holding capacity, dimensional stability, and resistance to moisture. It must be fixed to the bottom frame and stiffeners with corrosion-resistant self-tapping screws at maximum 300mm centers. All joints shall be staggered for structural integrity. •Floor Finish: Heavy-duty, homogeneous PVC vinyl flooring, 2.0mm thick (minimum), with a slip-resistant textured finish (Make: Gerflor, Tarkett, Armstrong, or equivalent). The vinyl shall be laid with full-spread adhesive application, ensuring no air bubbles. All joints shall be heat-welded using matching color PVC welding rod and then dressed flush to create a seamless, waterproof, and hygienic surface. The vinyl shall be turned up at the walls by 50mm to form a skirting. (L) Doors and Windows: Detailed Specifications (a) Main Entrance Door (6.5' x 3'): Construction: A robust door made from a 40mm thick pre-painted Galvalume sheet factory-filled with high-density polyurethane foam (PU) for thermal and sound insulation. The door frame shall be fabricated from a 1.6mm thick MS cold-formed section, welded to the main structure. •Hardware: Heavy-duty 316-grade stainless steel butt hinges, a high-security mortise lock with three levers, an aesthetic lever handle on both sides, and a heavy-duty hydraulic door closer suitable for external use.

(b) PU Insulated Flush Doors (3'x6'): • Construction: 35mm thick flush doors with a closed-frame construction of seasoned timber, filled with high-density PU foam and faced on both sides with pre-laminated MDF or pre-painted steel sheet. • Hardware: ISI-marked brass or stainless steel butt hinges, standard bore-hole lock set with a latch and lever handles. 5.30Aluminium Sliding Windows (3'x3' - 04 Nos): • System: Heavy-duty sliding window system with 1.4mm (minimum) thick aluminium sections. The frame shall be a tubular profile with thermal break. • Glazing: 4mm thick clear tempered glass for safety and strength. • Accessories: Safety Grill: Fabricated from 12mm diameter MS square/round bars, hot-dipped galvanized after fabrication, and fixed securely from the inside. Mesh: Stainless steel mosquito mesh (wire diameter 0.8mm) in a sliding or fixed frame. Canopy: A 600mm wide MS sheet canopy, painted to match the cabin, supported on brackets, to protect the window from direct sun and rain. Hardware: High-quality nylon roller assemblies, anodized aluminium handles, and a multi-point locking system.

(M) Supply and Installation • Manufacturing: The cabins shall be manufactured in a controlled workshop environment. • Transportation: The finished cabins shall be securely loaded onto trailers and transported to Visakhapatnam. All necessary permits for over-dimensional cargo (if applicable) shall be obtained by the contractor. • Installation: The contractor shall provide all necessary cranes and rigging gear for unloading and placing the cabins onto the prepared RCC foundation blocks. The cabins shall be levelled accurately using packer plates and then grouted or secured to the foundation prepared by the contractor. (Note: Prior placing of order of Porta cabin, The contractor shall submit detail skatches of porta cabin through Engr-in-charge (B/R) for approval of Accepting Officer. Order shall be placed only after obtaining written approval from Accepting Officer.)

M & L for modular point wiring surface type on wall and ceiling/roof etc with necessary fixing arrangements with PVC-FRLS insulated and unsheathed multi-stranded copper conductor of size 1.5 Sqmm, 1100 volts grade drawn through and including PVC casing capping, ISI marked of adequate size with all accessories/ fittings such as junction boxes, bends, tee, elbow etc with captive MS screw including PVC-FRLS insulated and unsheathed copper multi-stranded conductor of size 1.5 Sqmm, 1100 volts grade for continuous earthing including matching/finishing of new surfaces either by means of plaster of perish/ Putty or distemper / colour wash with same existing colour surfaces all as specified and directed for one Light Point/ Fan Point/ Bell Point complete all as specified and as directed

All as per item No 2 here-in-before but 5/6 Amps socket Point on Independent board.

All as per item No 2 here-in-before but for power point wiring with 2.5 Sqmm PVC-FRLS insulated, unsheathed, copper conductor, stranded 1100 volt grade cable and 2.5 Sqmm PVC-FRLS insulated, unsheathed, copper conductor, stranded 1100 volt grade cable as continuous earth lead complete all as specified and as directed.