Allmarc Steel. Inside India's Longest Road Cable-Stayed Bridge.

Author : Allmarc Industries | Published On : 08 Jul 2026

Allmarc Steel. Inside India's Longest Road Cable-Stayed Bridge.

Our Pylon Anchor Box Assemblies sit at the structural core of the Mumbai-Pune Expressway Missing Link, a landmark project inaugurated on Maharashtra Day 2026 and a moment of genuine pride for everyone at Allmarc.

When the Mumbai-Pune Expressway Missing Link was inaugurated on Maharashtra Day 2026, it marked the completion of one of India's most anticipated road infrastructure projects. At the heart of this project is a 650-metre cable-stayed bridge at Tiger Valley, now recognised as India’s longest road cable-stayed bridge. We at Allmarc Industries are proud to say that our fabrication work is embedded in its structure, in the very components that hold the bridge together.

This is not a peripheral contribution. The Pylon Anchor Box Assemblies we fabricated are part of the most critical load transfer system in a cable-stayed bridge. They sit inside the pylons and carry the force from each stay cable directly into the pylon structure.

Every cable fanning out from the bridge tower is anchored through a system we built. That responsibility shaped how we approached every step of this project.

What the project asked of us

We were contracted to fabricate 60 Pylon Anchor Box Assemblies, each weighing 18 metric tonnes, in E410 grade structural steel. The total fabrication volume across all units came to 1,000 metric tonnes. These are not numbers we state lightly. To deliver that volume to the tolerances required for safety-critical bridge infrastructure, on a project of this national significance, required our full capability.

E410 is a high-strength structural steel grade, selected for applications where the material needs to absorb and transfer heavy loads reliably over decades. Bridges like this one are designed for a service life that stretches far beyond any of our lifetimes. The steel we choose and the quality of the fabrication we deliver have to reflect that standard.

Every anchor box we fabricated carries the tensile force of a stay cable into the pylon. There is no component in a cable-stayed bridge where dimensional accuracy matters more.

The Fabrication Challenge

The geometry of a Pylon Anchor Box is not forgiving. Stay cables run at specific angles calculated by the bridge's structural engineers, and the anchor boxes must be fabricated to match those angles precisely. Any dimensional error in our work would translate directly into a misalignment of load paths within the pylon, something that is unacceptable in infrastructure of this kind. We held our tolerances tightly across all 60 units.

The work involved heavy plate processing at scale, in-house profile bending using our own bending facility, and extensive stud welding across complex welded assemblies. Each of

these processes had to be executed with strict geometry control, because the finished assemblies needed to fit precisely within the pylon structures on site. Our in-house capability meant we did not need to rely on external vendors for the forming or bending work, which gave us better control over dimensional accuracy at every stage.

Key Capabilities Deployed on This Project

● Exact stay cable anchorage geometry

● Stud welding and complex assemblies

● In-house precision profile bending

● Heavy plate processing at scale PEB manufactuer

● Large-scale structural fabrication

● Safety-critical quality compliance

The welding programme on these assemblies was particularly demanding. Complex welded joints under strict tolerance control, combined with the scale of each unit, required careful sequencing of operations to manage distortion and maintain the geometry of the finished assembly. Our teams worked methodically through each unit, and the consistency we achieved across the 60 units is something we are genuinely proud of.

Why this project matters to us

The Mumbai-Pune corridor is one of the most economically significant stretches of road in India. The Missing Link project has been in planning and development for years precisely because the terrain between Mumbai and Pune is so difficult, and the need for a safer, faster, more reliable connection between the two cities is so important. The Tiger Valley bridge is the engineering solution to the most challenging part of that route.

To be trusted with the fabrication of its most critical structural components is a reflection of where Allmarc stands as a manufacturer. We have built our capability through years of delivering demanding fabrication projects and investing in our facilities, processes and

people. This project is validation that the work we have put in is recognised by the clients and project teams who are looking for fabricators they can rely on when the stakes are high.

There is also something meaningful about contributing to infrastructure that will be used by millions of people over its lifetime. The bridge will carry commuters, freight and families between Mumbai and Pune for decades to come. Our work will never be visible to the people crossing it. It is inside the pylons, under load, doing its job quietly. That is exactly where we want it to be.

Looking ahead

India's infrastructure pipeline is substantial. Projects of the scale and complexity of the Mumbai-Pune Missing Link are not isolated occurrences; they represent a broader national commitment to building the roads, bridges, ports and structures required by a growing economy. At Allmarc, we have the fabrication capability, the quality systems and the experience to support that ambition at a level of precision that critical infrastructure demands.

The Missing Link project has shown what we can deliver when the engineering challenge is real and the responsibility is significant. We look forward to bringing that same standard to the projects ahead.