Lean Tools Applied to a Shipbuilding Panel Line Assembling Process

Abstract

To improve the shipbuilding process and obtain a more cost-effective production, several approaches are used today. The state of the art approach is based on newer production technologies, mainly steel cutting and welding technologies, which allows to improve the quality of the products and reduce the production time. Other approach, not so applied, is based on the reorganization some shipbuilding stages, applying some production improvement tools, like the Lean approach. The panel assembly line stage of the shipbuilding process is a key phase of the production sequence due to its relation with the remaining shipbuilding stages, essentially framed in the ship's block construction sequence, and its characteristics make it an accessible shipbuilding stage to apply the Lean approach tools. The Lean tools can be applied with a wide range of minuteness and on variable settings. The present paper analyses a rather simple modification on the panel line assembling process sequence, achieved through the application of some key concepts of the Lean approach. For the verification of the times and costs benefits due to the application of the proposed modification, a graphic interface tool was developed, allowing to analyse the costs and times results of the panel line production process.

Towards Digital Twinning of Fabrication Lines in Shipyards

“…Examples of the discrete-event simulation of material fabrication are presented in [5,6] at the strategic level. Similarly, discrete-event simulation was applied later on in the cases of the block erection process [40], ship hull job assignment [41], a robotized profile-cutting workshop [42], panel block production [43], and the panel assembling process [44]. The challenges and opportunities related to the transition from the conventional shipbuilding concepts to Shipbuilding 4.0 are discussed in [45], emphasizing the need for a reduction in production costs while increasing production efficiency.…”

Simulation of a Ship’s Block Panel Assembly Process: Optimizing Production Processes and Costs through Welding Robots

“…Welding procedures utilizing the unit panel method are commonly employed in the construction of large ships, as this approach offers improved work efficiency compared to traditional methods. In this method, panels with longitudinal stiffeners are first prepared and welded to the skin material through submerged arc welding [28]. The assembly process consists of several steps, as shown in Figure 2.…”

“…The robot's six degrees of freedom allow it to move in a variety of ways, including arm rotation, arm out-in, arm up-down, wrist swivel, wrist bend, and wrist twist, providing the necessary flexibility and precision to perform a wide range of welding tasks. The high level of precision and accuracy provided by the robot's six axes of movement make it well-suited for tasks that require a high degree of accuracy and repeatability [28]. After the unit panels are welded to the open block, the solid block is welded.…”

A Constrained Programming Model for the Optimization of Industrial-Scale Scheduling Problems in the Shipbuilding Industry

“…Shipbuilding is an extraordinarily complex and Engineering-to-Order industry where each order (ship) is managed as a customized project and involves an endless amount of resources and technologies [1][2][3][4][5]. Thus, each project entails a high degree of uncertainty and associated risk, leading to the need for methods and systems to plan, monitor, and control the production systems involved.…”

“…Manufacturers are striving to reduce costs and lead times to become more competitive while keeping quality standards. In doing so, they have been adopting techniques and production methodologies that come traditionally from other industries such as Lean Manufacturing and Product Lifecycle Management (PLCM) [3,4,6].…”