Kavach Towers

Kavach is Indian Railways’ own Automatic Train Protection system, developed with RDSO and formerly known as TCAS, the Train Collision Avoidance System. It works by radio between the locomotive, the trackside units and the station, so the network needs line-of-sight radio coverage along the whole route. A Kavach tower is the steel lattice tower erected beside the track or at the station that carries those trackside radio units and their antennas, together with the cabling, the platform and the lightning protection. The standard height along most routes is 40 metres.

Yes. We manufacture 40 metre Kavach towers at our Jangalpur works in Howrah, in both cyclonic and non-cyclonic forms, and we are RDSO approved for railway structures. We have manufactured lattice and tubular towers on this floor since 1995, and the galvanizing is done in our own kettle rather than sub-contracted — so the fabrication record and the coating record come from one works and one set of documents.

The difference is the design wind speed, and it changes the section sizes, the bracing pattern, the bolt grades and the foundation. A tower on a coastal or cyclone-prone route is designed for a much higher basic wind speed than one inland. The cyclonic 40 metre towers we build are designed for 180 km/h with an effective projected area of 15 m² of antennas. Non-cyclonic towers of the same height carry the same equipment at a lower design wind speed and therefore weigh less. Wind loading is worked to IS 875 Part 3 and the tower to IS 802.

EPA is effective projected area — the total wind-facing area of the antennas, mounts and cabling the tower has to carry, in square metres, at the heights they are mounted. EPA 15 means the tower is designed to carry 15 m² of equipment. It matters more than the antenna count, because two small dishes high up can load a tower harder than several panels low down. Send us the EPA and the mounting heights with the enquiry and the tonnage comes back right the first time.

The normal scope on a Kavach tower enquiry reads RDSO approval, RITES inspection, delivery at site — and often erection as well. The design is approved against the Railway drawing, the manufacturer works to an approved quality assurance plan, and the material is inspected by RITES or the inspecting agency named in the order before despatch. Indo East is RDSO approved for railway structures and works to an approved QAP on the tower.

Hot-dip galvanized, in our own kettle at Jangalpur, to IS 2629 and IS 4759. Our standard band is 75–85 microns, equivalent to about 610 g/m² of zinc, read on a calibrated dry film thickness gauge batch by batch. The standards state a minimum, not a ceiling, so heavier sections often read above the band. Because the galvanizing is on our own floor and not sub-contracted, the coating answer comes from us rather than from somebody we have hired.

Yes. We have offered civil, erection and painting for towers on a turnkey basis since 2005, and tower foundation and erection work runs alongside the fabrication. Tell us whether you want ex-works supply, delivery at site, or supply and erection, and the offer is priced accordingly.

Structural steel to IS 2062; fasteners to IS 1367, in the property class the design calls for — usually 5.6 or 8.8 on a tower of this height. Welding to IS 816 and AWS D1.1, inspected to IS 822. Earthing to IS 3043. Every heat is traceable from the mill test certificate through to the mark number on the despatched member.

Capacity is 18,000+ MT a year across fabrication and galvanizing, with a maximum single piece of 5 tonnes and a 7.0 × 1.2 × 1.6 m kettle — members longer than 7 metres are double-dipped, which we raise before quoting rather than after dipping. The works is on NH-6 at Jangalpur, Howrah, about 22 km from Kolkata Port, with road access for trailers.

The approved drawing or the tower type, the height, whether it is cyclonic or non-cyclonic, the design wind speed, the EPA, the bill of materials if you have one, the inspection agency, and whether the scope is ex-works, delivered or erected. With those, a formal quotation typically goes back within 48 business hours.