Girder Bridge Fabrication

Kothari Chemicals (Engineering Division) provides bridge girder fabrication for railway and road bridges from its works in Bhilai, Chhattisgarh. We make composite girders, steel plate girders, open-web girders and foot-over-bridge girders. Our RDSO registration (ID CBS/G/Reg/Kothari Chemicals) covers composite girders and other steel plate girders. Stated capacity is 18,000 to 20,000 metric tonnes a year, with single-piece handling up to 100 MT.

Request a quote with your drawings

What we fabricate

Our girder scope covers:

• Composite girders, with studs where the drawings call for them
• Steel plate girders
• Open-web girders, including riveted connections
• Road-over-bridge (ROB) and foot-over-bridge (FOB) girders
• Railway bridge members, including steel truss and plate girders

Plate, composite and open-web girders differ in span, weight, cost driver and inspection needs. The plate girder vs composite girder vs open-web girder guide compares them for buyers.

The RDSO registration covers composite girders and other steel plate girders, including open-web, road-over-bridge and foot-over-bridge girders. The RDSO-approved bridge fabrication page sets out the registration details, and how to verify RDSO vendor registration for a girder tender explains the check.

How a girder moves through the works

1. Design review. We check drawings, revisions, the bill of quantities, governing standards, inspection stages, delivery boundary and schedule before production starts. The delivery workflow from design review to dispatch covers this stage in detail.
2. Material. Steel is procured to the specified grade. Material test certificates and traceability are kept where the contract requires them. See steel plate traceability and mill test certificates.
3. Cutting and preparation. CNC plasma profile cutting, CNC three-axis drilling and sawing, bevel preparation, and hydraulic shearing and punching.
4. Fit-up and welding. Members are fitted and welded on automatic H-beam welding lines and by MIG/MAG, TIG, submerged-arc and stud welding. Riveting is available for open-web work. Welding follows approved procedures. See WPS, PQR and welder qualification.
5. Straightening and trial assembly. Hydraulic straightening corrects distortion. Where the contract requires it, we trial-assemble the girder to check camber and dimensions before release. See trial assembly, camber and dimensional control.
6. Surface protection. Automatic shot blasting, a blast room, a paint booth and metalizing equipment are used. Cleanliness, surface profile, coating system and dry-film thickness follow the project specification. Our dry-film thickness report guide explains how to read the record.
7. Packing and dispatch. Members are marked, protected and sequenced for loading. Long members get a route survey, transport permits and a lifting plan before release. See long steel girder transport and dispatch planning.

Quality and inspection

Dimensional and visual checks, dye penetrant testing (DPT) and magnetic particle inspection (MPI) are done in house. Ultrasonic testing (UT, PAUT) and radiography (RT) are arranged through qualified external support when the inspection and test plan calls for them. Those services come from NABL-accredited laboratories and AERB-approved radiography agencies. The extent of testing, the technique and the acceptance criteria are set by the approved inspection and test plan and the contract.

Our quality system is ISO 9001:2015, certificate 305026010110Q issued by QRO Certification LLP. The certificate is dated 1 January 2026, expires 31 December 2028, and its scope covers bridges and girders. The quality control guide for steel fabrication explains how the checks fit together.

Depending on the contract, a job can be supplied with material certificates, traceability records, WPS/PQR and welder qualifications, dimensional reports, NDT reports, calibration records, coating reports, non-conformance closure, inspection release notes, packing lists and a manufacturing record book.

Welders and welding inspectors hold BHEL Welding Research Institute certificates. Personnel qualification and validity are confirmed for each contract.

Governing standards and steel grade

The buyer defines the governing documents for each girder: IRS, RDSO, IRC, IS or other contract requirements, with their revisions. The buyer or designer also states the steel grade, welding and NDT extent, coating, inspection authority and dispatch splits. Common Indian structural-steel enquiries reference IS 2062 grades, but the exact grade, sub-grade and any impact requirement must be stated in the enquiry. Understanding bridge girder fabrication in India covers the standards in more detail.

Capacity and handling

• Annual fabrication capacity: 18,000 to 20,000 metric tonnes per year
• Single-piece handling: up to 100 metric tonnes

These are maximum stated capabilities, not open production slots. Production load, crane set-up (the works has multiple 50 T cranes) and logistics are confirmed for each package. Each lift is reviewed for geometry, centre of gravity, rigging, travel path and available resources. The works cover layout and marking, fabrication bays, assembly, stacking, shot blasting, metalizing, painting and dispatch support. For more on handling limits, read single-piece handling capacity in heavy steel fabrication.

Girder projects

Recent girder work in our executed-work register includes:

• NTPC Lara: 250 MT, ten 30.5 m open-web spans, including rivets. See the NTPC Lara open-web girder case study.
• MCVL-Handidua: 210 MT, four 36 m railway composite-girder spans.
• Pasan-Gevra-Pendea: 229 MT, three 24 m composite-girder spans.
• Kusmunda, Chhattisgarh: 195 MT, a 24 m road-over-bridge, including studs and painting.
• NTPC Tamnar: 96 MT, two 24 m composite-girder spans to an RDSO drawing.
• Kapan station, Odisha: 50 MT of FOB girders, including fabrication, blasting, metalizing, painting and supply to site.

Our largest recent programme was 10,000 MT of heavy fabrication for BHEL Trichy in FY 2025-26. Those were heavy steel components rather than girders. See heavy steel fabrication for that work. The full list of completed work is on the projects page.

What to send with an enquiry

A girder quotation is only comparable when the inputs are complete. Send:

• drawings with the revision register
• bill of quantities
• steel grade and governing codes
• welding and NDT requirements, and the inspection agency
• coating specification
• trial-assembly requirement
• delivery location, dispatch splits and site constraints

There is no universal lead time. It depends on engineering release, steel availability, member complexity, welding and NDT scope, coating, inspection hold points, transport permissions and current production load. A committed programme follows review of the full RFQ. The steel fabrication RFQ checklist lists the inputs in more detail.

Request a quote for girder fabrication

Kothari Chemicals (Engineering Division) Plot No. 3, Heavy Industrial Area, Hathkhoj, Bhilai - 490026, Chhattisgarh, India Landline: +91 788 2974 016 | Mobile: +91 93022 91000 | Email: kcenggdiv@gmail.com

Frequently asked questions

Is Kothari Chemicals RDSO-approved for girders?

Yes. Kothari Chemicals, the legal entity named in the registration, holds RDSO registration CBS/G/Reg/Kothari Chemicals for composite girders and other steel plate girders. The listed validity runs through 31 January 2031. Check the current status and category on the IREPS portal under Approval of Vendors (UVAM) before you bid. Registration details are on the RDSO-approved bridge fabrication page.

What is the longest girder you can make?

The stated single-piece handling limit is 100 MT, using multiple 50 T cranes. Recent completed spans include 36 m railway composite-girder spans and 30.5 m open-web spans. The maximum length for your job depends on member weight, transport route and lifting plan, which we review for each package.

How do you ship long girders?

Long members are dispatched to the delivery boundary in the contract. Before release we plan member dimensions, weight, loading sequence, route survey, transport permits, lifting points, support design and site readiness. See long steel girder transport and dispatch planning.

Which NDT methods do you carry out?

Dimensional checks, visual examination, dye penetrant testing (DPT) and magnetic particle inspection (MPI) are done in house. Ultrasonic testing (UT, PAUT) and radiography (RT) are arranged through qualified external agencies when specified. The extent, technique and acceptance criteria follow the approved inspection and test plan and the contract.

Do you provide the design?

Design responsibility is set for each package. We review drawings for manufacturability as part of the standard workflow, but that does not by itself make Kothari Chemicals the engineer of record. Confirm the design scope in the enquiry.