In an order calling for extensive custom-design and production, Vitrex – South Africa’s leading producer of enamel steel products for architectural applications – supplied the vitreous enamel steel panels and associated brackets for three new towering totems erected outside the King Abdullah Football Stadium in the Kingdom of Saudi Arabia.
The 60 000-seater King Abdullah Football Stadium forms part of the ultra-modern Sport City complex, dubbed the “Jewel in the Desert”, which features facilities that range from luxurious VIP lounges to 5-star accommodation. The impressive project is located in Jeddah, the second largest city in the Kingdom of Saudi Arabia, and the stadium, originally designed in 2009, is the venue for home matches of the two local football teams, Al-Ittihad and Al-Ahli.
Cristian Cottino, Sales & Marketing Director of Boksburg-based Vitrex, says the specification by Quality Architectural Systems LLC, called for the 23m high totems to be clad with heavy gauge Vitraclad vitreous steel panels in a special “Champagne” colour to match the colour of the main stadium’s cladding. “Where specific colours need to be matched in vitreous enamel, this calls for a relatively intensive, trial-and-error exercise by the Vitrex in-house laboratory. In developing custom-made colours, Vitrex has to ensure that the ‘new’ colour enamel is proven stable under production conditions, that the developed vitreous enamel coating is suitable for the intended application, and that it is as close as technically possible to the required colour,” Cottino explains.
But this contract called for more than just colour matching. “The enamel formulation for the totem cladding also had to fulfill high temperature resistance requirements. As some of the panels were to be installed within three metres of exceptionally hot discharge outlets on the totems, the cladding in this zone had to be able to withstand a temperature of 500°C. The scorching diesel fumes from back-up generators, housed at the base of the totems, are discharged through these outlets.”
Cottino says the maximum temperature that a vitreous enamel coating will withstand for extended periods depends on its original firing temperature and formulation. “Generally, for applications on steel, the vitreous enamel coating remains inert to a temperature of about 200°C below its firing temperature. The conventional firing temperatures using a steel substrate are around 800°C therefore vitreous enamel coatings maintain their thermal stability and remain inert up to a temperature of around 600°C.”
The need for heat-resistance, however, called for even more precautions with the totem cladding. “The vitreous enamel ground coat is usually applied over the entire fabricated piece, with the cover or colour coats applied only to the outer, visible face of the panels. But, for this project, Vitrex had to provide full cover colour coats to both sides of the panels to ensure thermal stability. Furthermore, to protect the laminated components at the back of the sandwich (composite)panels, Vitrex introduced a 75mm thick wired insulating matt, with a Maximum Service Temperature (MST) of 620°C, to provide a cold face temperature of 72.8°C when the hot face temperature is 550°C.”
Cottino said Vitrex’s scope of work also included determining panel deflection and whether the proposed panels would be able to withstand a design wind load of 2.2 kN/m2. “The structural design included determining the number of fixing points required for each panel, as well as the suitability of the fixings, bracketry and sub-structure proposed by the specialist subcontractor who carried out the installation of the totem panels and cladding system.”
In another bespoke requirement, Vitrex provided special 100mm diameter cut-outs in the panels fixed to the top of the totems to accommodate the mobile network’s antenna support arms.
The unusual export contract was secured for the Ekurhuleni company by Vitrex Europe and Middle East.
ABOUT VITREOUS ENAMEL STEEL CLADDING:
Vitraclad panels have been widely exported by Vitrex over many years, particularly for installations in the UK, Far East, and lately also increasingly to African countries. The vitreous (“porcelain”) enamel steel cladding has specific properties that provide exceptional durability and versatility, incorporating features such as:
Low maintenance: The selected colour of the panels is permanent, non-fading and the surface requires only simple, periodic maintenance;
Resistance to abrasion: The hardwearing surface is resistant to abrasive materials with a surface hardness rating of between 6 and 7 on the MOH scale;
Vandal-proof and impact resistant: It is extremely difficult to permanently mark the surface with knives, keys and screwdrivers. Unwanted graffiti and spray paint can easily be removed;
Thermal shock: Resists extreme temperature differentials and will withstand rapid cooling by water spray from 400 degrees C to room temperature over a 30-second period. As for the Saudi order, specific performance requirements can be addressed at the design stage;
Vermin-proof: The surface is impervious to attack by rodents and boring insects;
Acoustic and thermal insulation: Specific performance requirements can also be discussed at the design stage;
Hygienic: The absence of pores on the smooth, hard surface eliminates absorption of dirt and grease, and reduces the presence and growth of bacteria and mould;
Corrosion and solvent proof: The panels do not rust, even in extreme marine conditions. The coating is resistant to most alkalis, acids, organic solvents and unaffected by kerosene and vehicle emissions; and
Environmentally friendly: The panels have a working life well in excess of 30 years with minimum maintenance, do not require strong chemicals for cleaning, and are fully recyclable.