ERW tube welding lines: revamping or replacing?

Line obsolescence: range, scrap, productivity per hour, and additional production capabilities

The complexity of competition in the ERW tube market is constantly increasing. In many regions worldwide, the market suffers from overcapacity. This situation forces companies to find ways to become more competitive in order to survive.

How can you evaluate the competitiveness of production lines?

Typical parameters to measure if a production plant needs intervention include:

• Production range
• Diameter changeover times
• Scrap rates
• Hourly productivity (affecting personnel costs).

In many countries, safety reasons must also be considered.

These parameters should be compared with benchmarks of new plants. This comparison can reveal whether it's more advantageous to revamp the line or to replace or add a new one.

New production line: staff training, long lead times, costs, and space

Installing a new production line requires considering several aspects:

• Space requirements:

Modern lines may require much more floor space than the old ones. Rapid tooling change systems need more room than on-machine changes, and safety barriers expand the footprint. Higher productivity through increased speeds often necessitates longer roller conveyors.

• Lead times:

The production of the first tube from a completely new welding line can take up to 24 to 30 months after the order date for medium or large-diameter lines. Starting a new line involves time between the first tube and reaching full efficiency. A good workshop test of testable components can reduce these times, but not everything can be tested beforehand. Choosing reliable suppliers and careful planning can streamline the ramp-up process.

• Staff training:

Learning time for operators - even experienced ones - is difficult to shorten, especially for advanced automation skills.

• Total cost assessment:

The total cost of a new plant should be fully accounted for, including rolls, bead removal systems, impeders, welding coils, and auxiliary systems like cooling, filters, suction, soundproofing, coverings, connections, and compressed air. These logistics-related expenses form a significant part of the CAPEX.

Pictured are hot-rolled welded tubes distributed by Generaltubi Spa.

Revamping: existing spaces, shorter timelines, lower costs

Revamping always carries higher industrial risk:

- Production must be halted to modify a functioning line, with no possibility of reversal.

- During the initial start-up period after revamping, the revamped line may temporarily perform worse than the previous one.

- Unforeseen outcomes of revamping modifications can be unpredictable, even for highly experienced managers.
- As the market must be served, downtime must be very short and specific to avoid extended downtime that risks losing customers.

Conversely, revamping offers significant advantages:

- The cost of revamping is always much lower than a new plant.
- Thanks to the smaller scale of material requirements for revamping, it can be completed much faster than supplying a whole new plant.
- Existing spaces are largely reused, usually limiting the impacts on buildings, compared to installing a new line. Revamping is often the only possible solution due to the lack of space for new lines.

Conclusion: navigating the choice between revamping and new ERW lines

The pace of technological advancements in ERW tube production lines is relatively slow, often leading to plants operating with outdated equipment. This can result in obsolescence in terms of diameter change speed, productivity per hour, and production range breadth. Additionally, the range of producible products may be limited or lack the ability to handle newer steel types.

The decision between revamping an existing line or investing in a new one requires a thorough assessment of various factors. While revamping is generally more cost-effective, it also carries higher industrial risk. It demands expert management and careful planning to minimize disruptions and ensure a smooth transition. However, the potential benefits of revamping can be significant, including faster performance improvements at substantially lower costs compared to installing a new line.

Experienced professionals can guide companies through the complexities of revamping vs. purchasing a new line, ensuring the most effective and advantageous solution for their specific needs.


About the author:
Eng. Jacopo Grassino leverages over two decades of experience as a plant manager in leading plant and steel companies to offer high-level consulting on a wide range of industrial aspects. His areas of expertise encompass cost optimization and maximization of production efficiency, production start-up, definition and implementation of strategic plans, and team management. For more details on Eng. Grassino's experience and skills, or to request a tailored consultation, please contact him at:
Telephone: +39 3396821463
Email: [email protected]
LinkedIn: https://www.linkedin.com/in/jacopo-grassino/