Heavy Steel Fabrication in India, Built in Our Hyderabad Workshop
We fabricate heavy steel in our own Hyderabad workshop: thick plate, large welded sections, and components that need qualified weld procedures, NDT and full paperwork. For over two decades, EPC contractors and plant owners across India have sent us the jobs where accuracy and documentation matter as much as tonnage.
What counts as heavy 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: transfer trusses and deep plate girders for multi-storey industrial buildings; storage tank shells in heavy plate for large-volume liquid storage; 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 thicknesses and materials we work with
Heavy steel fabrication at Sun Corporation 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. Sun Corporation procures all heavy plate from approved mills with test certificates traceable to the specific heats used in fabrication.
How we weld thick plate
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 Sun Corporation, 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.
Weld testing and inspection
The three main NDT methods used in heavy steel fabrication at Sun Corporation 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. Sun Corporation 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.
Large girders and heavy columns
Deep plate girders for heavy industrial structures are built up from 16 to 20mm web plates and 25 to 40mm flanges, well into the heavy plate range. The flange-to-web welds are full-penetration and UT-inspected, and camber is set in the workshop and checked by survey before dispatch. For heavy columns we fabricate welded box sections, which give more torsional stiffness than equivalent hot-rolled sections.
| Item | Shop range |
|---|---|
| Carbon steel plate | 16–100 mm |
| Stainless steel | up to 50 mm |
| Welding | SAW / SMAW / MIG |
| Preheat | >30 mm |
| NDT | Level II UT / MPI |
Send us your drawings
To get a quotation for heavy steel fabrication from Sun Corporation, we need:
- structural or equipment drawings
- the material specification
- the NDT requirements
- 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 Sun Corporation for heavy steel fabrication. Also see: Heavy girder fabrication | Storage tank fabrication | Industrial shed fabrication
Thick-plate work feeds steel plate girders, heavy structural beams, heavy structural columns, heavy girder structures, and process pipe racks under the broader IS 800 structural steel fabrication umbrella. See also the fabricated products hub.