FOCUS ON COIL PROCESSING
Consistency of finish
Consistency of the Deco Linen finish is particularly important for prestigious buildings like ‘ 30 Hudson Yards ’ as it features large flat sections , where any visual inconsistency would catch the eye .
The pattern is produced at Outokumpu ’ s Dillenburg rolling mill , between Frankfurt and Cologne in Germany , by passing stainless steel sheet through rollers to emboss a pattern into the surface . Many production parameters can vary during this process and the final quality can be affected by the loads and temperatures used for rolling , as well as the condition of equipment and the chemical composition of pickling baths and lubricating oil .
Outokumpu ’ s usual product approval process includes the production of material samples before it carries out rolling and embossing of the main bulk of material . However , for a high-profile project like 30 Hudson Yards , Pohl will send its own quality managers to Dillenburg to work alongside Outokumpu ’ s technicians . Quality control begins with the arrival of large coils of stainless steel sheet from Outokumpu ’ s hot rolling mills . Before rolling and embossing for façade projects can start , the technicians evaluate the coils and select the ones with the best surface quality .
Once rolled , Pohl ’ s quality manager inspects one sheet from every coil to compare colour consistency , embossing depth and homogeneity . Only when they are satisfied , does the site release production and begin cutting the material into sheets .
Outokumpu also has stringent quality control in place for fabricators located further afield , whether supplying projects such as the Ping An Finance Centre in Shenzhen or the Sky View Towers in Dubai . For example , it uses the same experienced technicians who take charge of material selection , decide on the production parameters of equipment in the rolling mill and evaluate rolling quality . It also takes a similar approach to providing samples of material for the customer ’ s approval .
Consistency of the Deco Linen finish is particularly important for The Edge .
Accent panels and exterior skin of The Edge
Edge Skyline step
After taking delivery of the sheets , Pohl ’ s technicians formed and bent them into long slender accent panels that run from ground level to the very top of ‘ 30 Hudson Yards ’. They also created larger triangular panels to form the exterior skin of The Edge observation deck .
An important benefit of stainless steel is its long life in tough environments . As a dense city on an island surrounded by seawater and high air pollution from traffic , New York City is a harsh environment for its buildings . A further challenge is that the city authority uses de-icing salts to keep the streets free of ice and snow in the winter .
“ All this combines to create an environment rich in chloride ions , which are corrosive to steel alloys . However , as a stainless steel , Supra 316L has high corrosion resistance and is therefore ideal to ensure a long life ,” commented Outokumpu .
“ A real-life demonstration of the longevity of stainless steel is the Chrysler building , 3.2km from ‘ 30 Hudson Yards ’. Famous for its stainless steel art deco spire , it still looks pristine after 90 years and very low maintenance . To date , the spire has only been cleaned twice during necessary repair projects and the stainless steel itself remains in excellent condition ,” it added .
This long life highlights the sustainable nature of stainless steel as an architectural material . It lasts a lifetime with minimal maintenance and is fully recyclable . Sustainability is becoming more important for architects and property developers as they
react to the effects of man-made climate change . According to the UN Environment Programme , buildings are responsible for almost half of the world ’ s energy use .
Architects are pushing towards more sustainable buildings through initiatives like LEED ( Leadership in Energy and Environmental Design ). ‘ 30 Hudson Yards ’ has achieved LEED Gold certification , showing the effort made to reduce energy consumption and minimize the impact on the environment .
Some architects are now taking the next step towards greater sustainability by calculating the carbon footprint of their structures . To help them , Outokumpu has created environmental product declarations ( EPDs ) and LEED fact sheets .
Steel production is an energy-intensive industry – however , Outokumpu has worked hard to minimise its carbon dioxide emissions .
“ Our carbon footprint is three times smaller than the industry average , thanks to energy efficiency initiatives , use of recycled material as feedstock for production and purchasing low-carbon energy to power our mills ,” it told ISMR .
A new surface finish
The project prompted Outokumpu to develop a new surface finish .
Jörn Teipel , Outokumpu ’ s lead technical manager for architecture , said : “ Traditionally , we ’ ve always made linen finishes with a horizontal slub . This is a slightly thicker line that appears intermittently in natural fabrics and we have reproduced it in our Linen finishes . However , when working on ‘ 30 Hudson Yards ’, the specialist façade consultant Heintges suggested introducing a linen finish with the slub running vertically as this would create an even closer match between the material and the long vertical accent panels running up the building ’ s exterior .
“ While we were not able to introduce the new texture in time for ‘ 30 Hudson Yards ’ in 2016 , the vertical option is now available for architects to specify and is called Deco Vertical Linen M29 , whereas the horizontal version is Deco Linen M25 .”
When it opened in March 2020 , 30 Hudson Yards became the third tallest building in New York City and an important addition to the city ’ s skyline . Not only will the corrosion-resistant cladding help to maintain the building ’ s good looks over a long life , but it also highlights the way forward for sustainability in architecture . n
28 | sheetmetalplus . com | ISMR April 2021