Dr Sarath Obeysekera

 For a modern Chinese shipyard building a merchant vessel of around 1,000 tonnes of fabricated steel, the productivity of welders and fabricators is significantly higher than in most South Asian yards because of extensive automation, panel lines, robotic welding, and block

Fabricator (Fit-up):
0.8–1.5 tonnes per man-day

Welder:
0.5–1.0 tonnes per man-day (depending on weld length, welding position, and complexity)

Combined Fabricator and Welder Team:
0.6–1.0 tonnes per direct production worker per man-day

For a 1,000-tonne hull, assuming an average direct labour productivity of 0.8 t/man-day:

• Total direct production labour = 1,250 man-days
• If the workforce consists of:
  • 30 fabricators
  • 30 welders
    (60 direct workers)

Then fabrication and welding of the hull steel would take approximately:

1,250 ÷ 60 ≈ 21 working days

This excludes:

• Lofting/CAD
• Material handling
• Surface preparation and blasting
• Painting
• Pipe fitting
• Outfitting
• Electrical work
• Testing
• Management and quality control

Comparison with other shipyards

• Top Chinese/Korean yards: 0.8–1.5 t/man-day
• Japanese yards: 0.7–1.2 t/man-day
• Efficient Indian yards: 0.4–0.8 t/man-day
• Typical South Asian conventional yards: 0.2–0.5 t/man-day

Colombo Dockyard and in offshore fabrication, we  may have another benchmark commonly used in estimating: steelwork labour hours per tonne.

For commercial shipbuilding in China:

• 15–25 labour hours per tonne for hull steel fabrication is typical.
• World-class automated yards can achieve 10–15 labour hours per tonne.
• Offshore structures and naval vessels require substantially more, often 40–100+ labour hours per tonne due to tighter tolerances and more complex welding.

These figures are suitable for preliminary estimating and benchmarking against Sri Lankan shipyard productivity.

Those productivity figures are often useful when evaluating the competitiveness of a shipyard or preparing a business case. In practice, the biggest differences between Chinese and many South Asian yards are not just labour costs, but also:

• Automated panel lines and robotic welding.
• Extensive use of pre-outfitting before block erection.
• High material handling efficiency with gantry cranes and transporters.
• Digital production planning and nesting software that minimizes waste and rework.
• Well-trained, specialized teams performing repetitive tasks.

As you have previously advocated for Sri Lanka’s marine and offshore sector, improving productivity through automation, modern welding training, and modular construction could enable local yards to compete for regional shipbuilding and offshore fabrication work, rather than relying primarily on lower labour costs.

Dr Sarath Obeysekera