Samsung Heavy Industries' laser high-speed welding robot welds a curved surface in this September file photo. Courtesy of Samsung Heavy Industries
Robots have emerged as a solution for Korean shipbuilders in dealing with an intensifying shortage of labor, amid a soaring number of shipbuilding orders from global clients.
Domestic shipbuilders have wrestled with the shortage in recent years, as most skilled workers left shipyards during the previous shipbuilding industry slowdown in the mid-2010s, to take jobs in the semiconductor and battery sectors.
Although the government decided to increase the number of visas for foreign skilled workers to 35,000 this year from 2,000 in 2022, it has still been difficult for companies to recruit skilled welders here and overseas.
As a result, domestic shipbuilders have focused particularly on introducing welding robots to their shipyards, to address the labor shortage.
Samsung Heavy Industries recently succeeded in developing a “laser high-speed welding robot,” which enables significantly faster welding of membrane panels used in the cargo holds of liquefied natural gas (LNG) carriers, compared to the conventional method of plasma arc welding (PAW). The company is the nation's first shipbuilder to invent such a robot.
Since 2021, the company's research center has tried to develop a high-speed welding robot, to solve difficulties in hiring skilled welders and improving productivity in its welding process.
When welding a two-meter membrane panel, PAW takes five minutes, but the robot only takes one minute to finish the task, according to the shipbuilder. In addition, the robot can automatically find the spots to weld on curved surfaces.
“The laser high-speed welding robot will be a core technology for us to maintain our overwhelming competitiveness in the construction of cargo holds, which is the key process in building an LNG carrier,” said Choi Doo-jin, head of Samsung Heavy Industries Product Technology Research Center. “We will use the robot to build cargo holds of liquefied hydrogen carriers in the future.”
Hyundai Samho Heavy Industries, one of the subsidiaries of HD Korea Shipbuilding & Offshore Engineering (KSOE), has purchased dozens of collaborative robots from Denmark's Universal Robots and Korea's Rainbow Robotics. Collaborative robots refer to robots that can interact with human workers more safely within a shared space, or in close proximity.
According to the shipbuilder, its collaborative robots enable unskilled workers to precisely weld the spots that are inaccessible to humans.
“Amid the labor shortage in the shipbuilding industry, collaborative robots can be good alternatives,” said Ryu Sang-hun, senior vice president of Hyundai Samho Heavy Industries Automation Innovation Center. “We will integrate robotics with the shipbuilding industry to enhance quality and competitiveness.”
HD Hyundai Heavy Industries, another subsidiary of HD KSOE, has also used collaborative robots since 2018 for assembling blocks. The company is now using an upgraded version of the robots in orbital welding.
HD KSOE plans to transform the shipyards of its subsidiaries into “smart shipyards” by 2030. Once the transformation is completed, the automated manufacturing process using robots and artificial intelligence will be seen in shipyards.
Earlier this year, Hanwha Ocean succeeded in developing a collaborative robot that can weld a vessel's plumbing. The development project was launched in 2019, when the shipbuilder's name was Daewoo Shipbuilding & Marine Engineering, which had been under the supervision of creditors run by the Korea Development Bank, until Hanwha Group acquired the shipbuilder.
After dozens of rounds of testing and much trial and error, the company finally developed a robot that can enhance worker productivity significantly.
Before the use of the robot, workers had to carry a torch worktable weighing over 30 kilograms and adjust its location manually. Hanwha Ocean said the robot reduced preparatory work by 60 percent, contributing to productivity and placing less physical demands on workers.
“We are developing technologies to use the robot in welding ordinary pipes,” a Hanwha Ocean official said.
At the time the shipbuilder announced its development of the robot in January, First Vice Minister of Trade, Industry and Energy Jang Young-jin visited the company's shipyard on Geoje Island in South Gyeongsang Province and promised that the government would offer over 5 billion won ($3.7 million) in support for local shipyards to help them cope with the labor shortage through automation and digitalization.
Hanwha Ocean itself also plans to invest 300 billion won to build a “smart yard,” which can enhance safety and help the company deal with the decrease in skilled manufacturing workers.
A Hanwha Ocean employee operates a collaborative welding robot at the company's shipyard on Geoje Island in South Gyeongsang Province in this January file photo. Courtesy of Hanwha Ocean
Solution to SAPA
Shipbuilding industry officials also expect robots to reduce industrial accidents.
Data compiled by the Ministry of Employment and Labor showed that around 2,000 industrial accidents have occurred every year in the shipbuilding industry. The industry has been especially vulnerable to industrial accidents as shipyards are full of sharp metal structures and their workspaces are cramped and located far above the ground.
Since the Serious Accidents Punishment Act took effect last year, however, shipbuilders and other Korean manufacturers have been more proactive regarding the prevention of fatal industrial accidents, because the law states that a company's CEO can be sent to jail if a serious worksite accident occurs when the company has not taken sufficient safety precautions.
“Although it is impossible for robots to fully replace human workers in the labor-intensive shipbuilding industry, they will contribute to addressing the labor shortage and preventing fatal industrial accidents,” a shipbuilding industry official said.