Obayashi Corporation has developed a new fireproof coating spray robot (second-generation) to further improve productivity by promoting automated construction. The new model was introduced at construction sites in Tokyo in November 2023 and is expected to spray coat a total area of over 9,000 m² by the end of FY2023.

Fireproof coating treatment is used in steel structure buildings to prevent fire damage to the steel frames. When using the semi-dry rockwool spraying method,(*1) which is common for this type of work, the rockwool tends to scatter and float in the air when sprayed, so any construction or skilled sprayers involved in the job must wear protective clothing and dust masks. The shortage of skilled sprayers is primarily due to the fact that the work can be tough and the environment harsh, especially in the summer.

Obayashi Corporation developed its first generation of fireproof coating spray robots in 2019, which are currently being used on multiple construction sites of primarily medium- to high-rise office buildings. The fireproof coating spray robots can spray roughly the same area per day as a skilled sprayer while ensuring stable construction quality, such as achieving coating thickness and density that meet construction management standards. The introduction of fireproof coating spray robots reduces labor and is helping alleviate the shortage of skilled construction workers.

However, several issues came to light during repeated use, such as the need to make the robots smaller and lighter to further improve productivity and quality, the time and effort required to accurately align the spray points, and the need to fully grasp the relative error between the robot and the steel beams. The newly developed second-generation model solves these issues through the following functional enhancements.