After troubles with the installation of the massive steel piles that will support the $3.9 billion replacement of the Tappan Zee bridge near New York City, bridge builder Tappan Zee Constructors has brought in robotic welders.
About 1,000 of the steel piles will support the new twin-span bridge that crosses the Tappan Zee, a natural extension of the Hudson River.
The robots are operated by a team of six welders from Wilkinson Technologies out of Layfayette, Louisiana according to a report from the Journal News. The Wilkinson teams says the robotic welders can connect sections of the steel piles twice as fast in some cases as a person and reduce the chances of defects. Up to a dozen robots can be attached to a track around the pile, quickly welding the sections together.
However, the machines are still closely monitored by a team of workers as the robots cannot detect when something is off.
TZC reportedly experienced trouble installing the piles from the beginning of the project, saying that many local welders didn’t have experience working with that large of a pile. And though the pace eventually picked up, in April TZC said it, like many other contractors across the country, was unable to find qualified experienced welders for the job. In a series of welding tests TZC gave to job candidates, only 23 percent were passing. Since then, the test passing rate has improved to 35 percent.
Local union officials said much of the fault lies with TZC which they say has changed welding methods five times to date, making it difficult to adequately train and certify welders for the job.
The team of welders that operate the robots have been on the job for a month. Things seem to be going well, but it’s unclear if any more robotic welders will be called in. The project is expected to be completed by 2018.