“Made in Wuhan” internal welding robot solves the world’s problems

Hubei Daily News (Reporter Wang Chenglong, Correspondent Hu Qiongzhi) On a 50-meter-long production line, 6 pieces are slightly larger than a fist.Robot, drilled into 6 U-ribs of steel plates with a height of 28 cm, and carried out welding. Soon, these steel plates will be installed on the Zhuankou Yangtze River Bridge in Wuhan. The successful development of these robots will greatly extend the life of steel bridge welds.
Due to the advantages of low cost and few piers, steel structure bridges have become the mainstream of bridge construction, such as the San Francisco Bridge and the Hong Kong-Zhuhai-Macao Bridge. Steel bridges need to weld U-ribs (a U-shaped steel bar) under the deck steel plate to enhance key properties such as torsion resistance and compression resistance, but U-rib internal welding is a world problem. Today, this problem has been successfully solved in Wuchuan Heavy Engineering Co., Ltd. (referred to as Wuchuan Heavy Industry).
Zhang Hua, senior engineer of Wuchuan Heavy Industry, explained that taking the Zhuankou Yangtze River Bridge as an example, each steel plate is 12 meters long, and 6 U-ribs need to be laid longitudinally under the steel plate. Each U-rib is 12 meters long, and the closed groove is only 28 centimeters high and 30 centimeters wide, so people cannot drill into the welding. The common practice in the world is to externally weld U-ribs and steel plates from the outside. In this way, the weld between the U-rib and the steel plate generally needs to be overhauled in 15 years.
In 2011, Wuhan LixinautomationTechnology Co., Ltd. and Wuhan Shipbuilding Industry Co., Ltd. jointly tackled key problems. Last year, the U-rib internal welding Robot was developed, and a production line was set up in Wuchuan Heavy Industry.
The reporter saw that there is a “two-story building” at the end of the production line, which is the “brain” of the production line, equipped with a flue gas recovery system and an operating system. The “brain” sticks out six “finger”, and each “fingertip” has a welding Robot. The robot drills into the U-rib, and it goes back and forth for 40 minutes, and the internal welding of a steel plate and the U-rib is completed.
The general manager of Wuhan Lixin introduced that the space of the U-rib is small and almost airtight, and the high temperature and smoke during the welding process will affect the “intelligence” of the robot. Therefore, it is the key to the technology to teach the “brain” to properly exhaust smoke, supply air, and dissipate heat.

In March of this year, Wuhan Lixin sent the internal welding products to Huazhong University of Science and Technology for testing. The data showed that only external welding, under the pressure of 120 MPa to 160 MPa, the U-rib weld was exposed to cracks after 4.7 million heavy pressures; After adding internal welding, under the pressure of 120 MPa to 220 MPa, it has been subjected to 9 million times of heavy pressure, and there is still no crack. Wuhan Lixin successfully applied for 3 international patents and became the only service provider in the world.
Expert analysis shows that with this internal welding technology, the total cost of bridge construction will hardly increase. The successful research and development of this technology will enhance the core competitiveness of Chinese enterprises in the field of international bridge construction.


The Links:   3HAC7349-1 3HAC029818-001

Published on 09/07/2022