Welding Wonders: Cloud Gate, Chicago

Here at Adam’s Gas, we don’t just provide gas solutions for barbecues and bars, we also provide welding gas for all you avid welders out there. Even though it is the barbecue season, we also think that welding deserves a bit of a shout out too, so we’ve decided to start a series in which we take a look at some of the welding wonders of the world. First up, let’s take a look at one of Chicago’s most iconic structures; Cloud Gate. “The Bean” Cloud Gate is a welding masterpiece created by a British artist named Anish Kapoor. Inspired by liquid mercury, Kapoor enlisted the help of over 100 metal fabricators, welders and engineers to create the thirty foot high, sixty foot long sculpture which is now the centrepiece of AT&T’s Plaza at Millennium Park. Although the outside of Cloud Gate, affectionately named “The Bean” due to its significant resemblance to a kidney bean, looks sleek and smooth, the real work underneath the seamless plates is what we are interested in. The Construction The construction of the Bean was made possible when two companies were asked to collaborate to make the structure possible. Performance Structures Inc. (PSI) of Oakland California led the creation of the shell structure and MTH of Illinois was in charge of installing the structure once the pieces were completed. The unique shape of the structure provided a challenge for the fabricators when it came to producing the outer plates. With some of the largest plates weighing in at up to 1,500 pounds, one of the biggest tasks was plasma cutting the ¼-3/8 inch thick plates and forming them to create the precise curvature requires. Ethan Silva was the man leading PSI’s project. He has had previous experience in creating similar structures, and when speaking to thefabricator.com, Silva commented that PSI overcame this challenge by “very accurately forming and fabricating the rib-system framework for each plate. That way we could accurately define the shape of each plate.” Welders then flux-core stitch-welded the accurately curved plates onto this rib-system to create a strong, high quality base structure system. The Assembly Once the plates and the rib system were complete, they were transported across the country with some PSI workers to MTH in Illinois to begin the assembly. The internal frame of Cloud Gate, uses pipes which are arranged in a criss-cross like pattern. These help hold up 2 huge O Ring structures which make up the internal frame of the structure which was achieved using stick welding and gas metal arc welding for reinforcement. A suspension system was used to move the plates into place over this frame, lining up perfectly thanks to the meticulous measurements put in place at PSI. Plasma welding was used to weld the plate seams from the exterior. Silva said that “The next big fabrication challenge of this project was to weld the seams without losing the accuracy of the shape due to weld shrinkage distortion”. The welding that was needed had to be a full penetration weld, but the employees could only weld from the exterior. Using a technique that required the use of a custom built chamber on the back side of the plates, welders made their welds and then the channel was flooded with inert gas and fed directly inside the joint. Once these tricky welds were completed, Cloud Gate was sanded with special ceramic sandpaper to remove any marks left by the seam welds. Once all the seams and marks were gone, The Bean was polished with rouge, a waxy substance that some jewellers use as polish. After 5 years of planning and construction, the Cloud Gate was ready and was unveiled on the 15th of May 2006. The sculpture was deservedly awarded the “Outstanding Achievement in Welding” award by the American Welding Society in 2007. We think it is a fantastic example of how effective welding can be and what a good weld can achieve. If you are a welder and are looking for specialist welding gas, we have a wide selection of gas solutions for you. Finding yourself in need of a new argon gas bottle? Contact our fantastic team at Adams Gas today by calling 0800 195 444 and we will be more than happy to help you.

For more information on Welding Wonders: Cloud Gate, Chicago talk to Adams Gas