Inrotech mobile robot welding of ships with double hulls


Inrotech has contributed to robotic automation solutions for the Odense Steel Shipyard, Lindø (AP Moller Maersk) since 1998. In 2009 they decided to implement Inrotech’s intuitive and intelligent welding robots at the shipyard. The case is described in details below. You can also find a video about this Inrotech welding robot technology case, introducing the unique novelty ALPT (Adaptive Logic Programming Technology) on or on

The objectives

Odense Steel Shipyard, Lindoe wished to streamline the welding of the ballast tanks of double hull vessels, thus obtaining:
1.  A better and more uniform welding process
2.  Shorter lead time
3.  Improved working environment for employees 

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The technical solution finally implemented

Ship blocks of 32x16m are welded with a team of 8 Inrotech welding robots. The Inrotech welding robots are imported from platforms where exhaust, fresh air supply, CO2 and electricity are also available. Feeding rails are carrying not only the Inrotech welding robots into the large ship blocks, but also all necessary supplies for the Inrotech welding robots and shipbuilders.
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Speed, consistent quality and good working environment

The rail system is mounted and dismantled manually and used to transport the robot and supply cables that run into the ship sections through manholes. Rails and cables are also used by shipbuilders when they prepare for the robot, and thereby reducing costs due to easier transport of materials and less wear on cables etc. After setting up the grid and tagwelding of section elements, the Inrotech welding robot units are deployed for automatic welding. The Inrotech welding robot is lowered from the feeder rail onto the robot´s own grid system and then automatically moves from task to task on the external axis. After finishing the task, the system is moved via the feeder rail to the next room or to the next ship section. 

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Compact self-thinking Inrotech welding robots

Compact mobile robotic devices consisting of a robot (Fanuc), a welding unit and a control unit are deployed as one unit into the ship through the man holes.

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Simplified robot language

The intelligent and intuitive robotic solution from Inrotech is in the robot´s own internal system language that allows programming of intelligence into the robot. Hereby detailed definitions of the welding tasks are not necessary because the Inrotech welding robot is able to dynamically adapt to variations within the foreseeable. The Inrotech welding robot is programmed to identify the nature and dimensions of the task using a laser sensor. Thus the risk of mismatch between the fixed programs or programs based on design drawings and actual conditions completely disappears. The shipyard also saves time and money for not having expensive programmers doing the transfer of designs and drawings.

The operator controls the Inrotech welding robot through a simple menu structure that is simplified into a few manageable options. Basically all of the pre-defined workspace is welded - unless the operator decides not to weld certain areas or to skip specific welding tasks.
The operator is able to master the operation with a minimum of training, a few minutes is typically enough. Super users are not something Inrotech operates with. However, as in any mechanical system, there is a need for a certain understanding of the system to solve operational issues. The operator’s tasks are mainly related to the exchange of simple spare parts at the Inrotech welding system and general maintenance.

The results

  • Improved profitability
    The mobile robot welding solution from Inrotech gave even more than was paid for. Besides the reduction of welding time, an additional gain was a remarkable improvement of internal logistics and production flow. Because of the innovative solutions, OSS was able to automate tasks that previously were not possible. Labour-intensive welding tasks are now faster, better and with less direct labour costs than previously.

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  • Higher efficiency, better quality…
    is now possible in automation of repetitive welding jobs. The improvements are made possible by mechanical, programming and operating-related innovation, which allows continuous welding without operator intervention. Welding quality is improved at the same time because of greater consistency and fewer mistakes.

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  • Zero operator errors
    With Inrotech’s intuitive user interface, which does not require any robot programmer experience or specific robot knowledge, Inrotech has made it possible for any shipyard or other heavy industrial company with large repetitive welding tasks, to automize welding operations easily. With Inrotech’s unique welding robot technology (ALPT) and user friendly and very intuitive touch screen, the introduction of robotics is made into a very foreseeable process where everyone can participate.

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  • No need to remember programs…
    lines or codes. Start, stop, pause, continue. The operator makes use of few and simple menu options. The built-in intelligence of the system thus reduces the operator’s ability to make mistakes, but also ensures that the operator, who is often the welder, can easily adapt to this new way of working.

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» Inrotech has developed a new robot technology for Odense Steel Shipyard and pushed the boundaries of robotic application. Mobile robots that can detect welding jobs automatically and perform a continuous high welding quality is no longer a fever imagination of shipbuilders, it has become a reality with Inrotech’s mobile welding robot system. «

Thomas Knudsen. VP, Odense Steel Shipyard, Lindø Denmark