Heavy steel fabrication in India — thick plate structures, pressure vessels and large industrial components

Heavy steel fabrication in India sits at the more demanding end of the structural steel market — work that involves thick plate, large section sizes, complex weld procedures, intensive non-destructive testing, and detailed quality documentation. It is the kind of work where the difference between a competent fabricator and an average one is visible in the quality of the finished product. Suncorporation has been doing heavy steel fabrication for industrial clients across India for over two decades, with our own workshop, our own qualified welding teams, and our own NDT capability.

What defines heavy steel fabrication

Heavy steel fabrication generally means steel fabrication involving plate thicknesses above 16mm, component weights above 5 MT per piece, or structural complexity that requires more than standard structural steel fabrication capability. In practice, it includes: crane runway beams and crane supporting structures for overhead cranes above 20 MT capacity; transfer trusses and deep plate girders for multi-storey industrial buildings; storage tank shells in heavy plate for large-volume liquid storage; pressure vessels and heat exchangers; pipe rack structural frames for process plants; equipment skids and base frames for large industrial machinery; and fabricated structural elements for power stations, ports, and heavy infrastructure.

EPC and PMC teams can review our workshop credentials and QA/QC records before tender submission.

Plate thickness and material in heavy steel fabrication

Heavy steel fabrication at Suncorporation handles plate thicknesses from 16mm to 100mm in mild steel and carbon steel, and up to 50mm in stainless steel grades 304 and 316. At plate thicknesses above 25mm, IS 2062 requires Charpy impact testing of the plate material in addition to the standard tensile and bend tests — this confirms that the steel has sufficient toughness at the design temperature to resist brittle fracture. For pressure vessel applications, IS 2002 steel with more stringent chemistry and toughness requirements is specified. Suncorporation procures all heavy plate from approved mills with test certificates traceable to the specific heats used in fabrication.

Welding in heavy steel fabrication

Welding is the core process in heavy steel fabrication, and getting it right requires qualified procedures and qualified welders. IS 9595 governs the qualification of welding procedures for carbon and carbon-manganese steels in India; IS 7307 covers welder performance qualification. At Suncorporation, all welding in heavy steel fabrication is done to qualified Weld Procedure Specifications using SAW for long straight runs on thick plate, SMAW for position welding and root runs in restricted access, and MIG for medium-thickness work. Preheat is applied using electric resistance heating blankets for plates above 30mm, with temperature confirmed by contact thermocouple before welding starts and monitored throughout.

Non-destructive testing in heavy steel fabrication

The three main NDT methods used in heavy steel fabrication at Suncorporation are ultrasonic testing (UT) for volumetric inspection of full-penetration butt welds, magnetic particle inspection (MPI) for surface and near-surface defect detection in ferromagnetic steel, and liquid penetrant testing (PT) for surface defect detection on stainless steel and non-ferromagnetic materials. Suncorporation has in-house qualified UT and MPI technicians certified to Level II per ASNT SNT-TC-1A. For projects requiring third-party inspection, we coordinate the inspection agency’s access to our workshop during production rather than at the end, so that inspection findings can be addressed before fabrication is too far advanced to correct easily.

Heavy steel fabrication for crane structures

EOT crane runway beams for cranes above 20 MT capacity use plate girders with web thicknesses of 16 to 20mm and flange thicknesses of 25 to 40mm — well into the heavy plate range. The longitudinal flange-to-web welds are full-penetration and need UT inspection. The camber — the pre-set upward bow in the unloaded girder — needs to be set accurately and verified by survey. The top flange surface for the crane rail needs to be flat and level to the rail alignment tolerances specified in IS 807. Suncorporation fabricates crane columns — particularly for heavy overhead cranes — from heavy welded box sections that provide higher torsional stiffness than equivalent hot-rolled sections.

Heavy steel fabrication cost in India — 2026

• Heavy structural members, 16 to 30mm plate, standard IS 800 inspection: Rs 95,000 to Rs 1,15,000 per MT ex-workshop, fabricated, primed.
• Crane runway beams, 20 to 50mm plate, UT and MPI inspection: Rs 1,10,000 to Rs 1,45,000 per MT ex-workshop.
• Transfer trusses and deep plate girders, full NDT: Rs 1,20,000 to Rs 1,60,000 per MT ex-workshop.
• Pressure vessels and process equipment, carbon steel: Rs 1,20,000 to Rs 1,80,000 per MT depending on complexity and inspection requirement.
• Stainless steel process tanks and vessels: Rs 2,50,000 to Rs 4,00,000 per MT — stainless steel material costs roughly three to four times mild steel.

Enquiries for heavy steel fabrication

To get a quotation for heavy steel fabrication from Suncorporation, we need the structural or equipment drawings, the material specification, the NDT requirements, and the inspection and documentation requirements. If drawings are not yet available, a description of the component — type, approximate dimensions, material, and end use — gives us enough to provide a budget estimate. We respond to all heavy steel fabrication enquiries within 24 hours.

Contact Suncorporation for heavy steel fabrication. Also see: Crane girder fabrication | Storage tank fabrication | Industrial shed fabrication