PrelaqAcademy. Development, production, use and future prospects

Transcription

1 PrelaqAcademy 1 Prepainted Development, production, use and future prospects Growth in the use of prepainted in Europe The various coatings on prepainted Lars Schön is the Product Manager for Prelaq the prepainted from SSAB Tunnplåt. He describes how the market for prepainted has grown up to now, outlines the general properties of prepainted, and gives examples of the many applications for which prepainted steel sheet is well suited. The prepainting process Johan Anderson was the Managing Director of the Swedish Institute of Steel Construction (SBI) at the time this paper was prepared. This is an independent industrial research institute which is focused on promoting steel construction by applied research, development and information. SBI has a wide international network of contacts and is a leader in environmental matters. Johan Anderson describes the future prospects for prepainted as a construction material. Prepainted and the environment

2 Growth in prepainted consumption is unaffected by the business climate Lars Schön, Product Manager, SSAB Tunnplåt The first coil coating line in Sweden was commissioned in 1959 and SSAB Tunnplåt started its first coil coating line in Borlänge in SSAB Tunnplåt produces annually more than 40 million sq.m. of prepainted sheet under the Prelaq brand name. This quantity is equivalent to a 1200 mm wide strip wrapped around the Earth s equator. SSAB Tunnplåt is the biggest manufacturer and supplier on the Swedish market. More than 700 million sq.m. of prepainted is produced annually in Europe, while the figure for the remainder of the world is 1,400 million sq.m. The consumption of prepainted has increased steadily year by year, regardless of the general business climate. During the past 10-year period, the consumption of prepainted has risen at the rate of around 10% annually. Properties of prepainted Prepainted has a core of steel, from which it derives its strength. The material is traditionally used for buildings, The various coatings on prepainted 1 Steel sheet 2 Metal coating 3 Passivation layer 4 Primer 5 Top coat 6 Removable protective film 7 Reverse side coating and the steel is therefore a structural steel with a defined yield strength. This is necessary to ensure that the steel structure will be able to withstand the loads for which it has been designed. To achieve good anti-corrosion properties, the steel core is coated with a metal layer consisting of zinc or an alloy of aluminium and zinc. In the first stage of a coil coating line, the sheet is pretreated in a number of water solutions that ensures good adhesion of paint. The next stage consists of applying the primer onto the front surface of the to provide protection against corrosion and to improve the adhesion of the top coat. A coating that serves as protection during transport is applied to the reverse side of the sheet. Finally, the top coat is applied, for which the user specifies the paint system and the colour. The various paint systems available include polyester, plastisol, PUR and PVDF, each of which has different properties, which are suitable for different environments and applications. The range of available colours and surface structures is virtually unlimited. However, statistics show that around 15 colours account for the vast majority of colours specified. These colours are known as the standard colour range, which varies from country to country. The buyer can also specify special colours. The sheet can also be coated with a film. SSAB Tunnplåt film-laminated is known as Dobel and is used mainly in the shipbuilding and offshore industries, since it conforms to the fire protection requirements in these indu-stries The prepainting process, coil coating Consumption of prepainted during the past 10 years. (Source: ECCA) Hot-dip galvanized Cold-reduced Aluminiumzinc coating Chemical pretreatment and priming 2

3 and can be supplied in a variety of colours, patterns and surface structures. Methods of working prepainted Zinc coating and paint systems have been developed to the point where today s prepainted has very good formability. Prepainted sheet can be worked by cutting, roll forming, bending, folding and so on. Due to its good formability, the sheet can be used in advanced forming operations, such as in deep drawing. Due to its good workability properties, coil-coated is also finding growing applications in the engineering industry. Prepainted in the building industry Prepainted sheet is mainly used for roofing and wall cladding, but it is often also given a load-bearing function in walls, roofs and floor structures. Traditional profile sheet is used for roofing, and the cross-sections range from small corrugations to deep profiles that provide higher load-bearing capability. Steel sheet roofs produced by the long strip roofing method that requires extra-mild steel known as PLX grade is a speciality in the Nordic countries. It is applied to an insulated and load-bearing roof. The use of roofing tiles made from prepainted has increased at a brisk pace. They are formed out of prepainted sheet, and the product is attractive in appearance, and also in cost and quality. Profiled is often used for wall cladding of industrial and other large buildings. Curtain walling in prepainted steel is to a growing extent on buildings of a more prestigious nature, such as air terminals, offices and shopping centres. Composite panels consisting of profiled on each side of a core of insulating material are becoming increasingly common in the construction of entire walls. The whole wall is made up of composite panels, which enables the wall to be built up quickly and cost-effectively. Polyester PVDF Plastisol PUR Gutters, downpipes, fittings and industrial doors are other major fields of application for prepainted. The environment and prepainted sheet Since prepainted sheet is based on steel, its recycling properties are the same as those of any other steel. Steel in general and prepainted offer three unique environmental benefits. In the first place, all steel contains recycled material. All steel production is always based entirely or partially on steel scrap. In the second place, steel and prepainted are always 100% recyclable. Almost all steel scrap is painted to a greater or lesser extent, and neither the metal coating nor the paint is an obstacle to remelting. In the third place, steel can always be remelted into exactly the same product, without any loss of quality. Once steel has been produced, it can be used in a virtually perpetual recycling process. Calculations made at the Swedish Institute of Steel Construction show that only 5 to 6% of the steel is lost when it is recycled*, which occurs mainly when the steel is melted. Steel is included in a continual recycling process * Johan Anderson, Mathias Borg. Recyclability of Light-gauge Steel Studs. Swedish Institute of Steel Construction Report No. 182:10, Stockholm, Facts about prepainted 1. The first coil coating line in Sweden was commissioned in SSAB Tunnplåt started its first coil coating line started in Borlänge in The annual production of prepainted in Europe is 700 million sq.m. 3. The consumption of prepainted has steadily risen every year, regardless of business climate fluctuations. 4. Prepainted consists of a steel core, a metal coating, a primer and a top coat. 5. Today's prepainted can be used in advanced forming operations such as roll forming, bending and deep drawing. 6. Steel and prepainted offer three unique environmental benefits. They always contain recycled material, they are 100% recyclable, and they can be made into exactly the same product again, without loss of quality. 3

4 Prepainted in tomorrow s construction work Johan Anderson It may seem somewhat pretentious to claim that a steel and prepainted steel will be tomorrow s materials in the building industry. But the properties of steel provide solid grounds for my claim. Purpose-made advantages My claim is founded on the flexibility of steel. The purchaser can specify exactly what it is he needs. The supplier of the steel material can then produce the steel exactly in accordance with the specifications, and the parts will then fit exactly when they are assembled on site. This results in shorter construction time and no wastage. These properties are unique to steel. Other materials demand a relatively large amount of adjustment work on site, and many materials also involve wastage that may amount to percent. Steel industrializes the construction work The very robust growth in the use of steel and prepainted steel is due to steel being more economical than other materials. Anyone who has realized this will not build things by hand on site, since production can be done more cost effectively within a workshop. The use of prepainted and products that contain prepainted sheet is therefore growing in the building industry. At the present time, prepainted is used mainly for industrial buildings. But the use of prepainted sheet can naturally be justified for all types of buildings, since wall cladding and roofing made of prepainted are rigid, durable, lightweight and cost effective. All of this can be expressed as prepainted having the highest ratio of performance to weight or performance to price. The future of prepainted The clear trend at the present time is that of a higher strength will be used in the future for making products in prepainted. The sheet will therefore be thinner and lighter. As a result, the will be more environmentally friendly to transport and easier to handle and assemble on site. When the is of higher strength, it will also encourage the use of advanced forming operations. Prepainted sheet will then be more refined and technically more advanced, which will also offer new aesthetic opportunities. Another trend is a clear focus on the end use and the overall use, i.e. integration of all stages in the process. There is still enormous potential for improving productivity in the building industry. This means that the products used will be more tailor-made, and what was previously done on site will now be done at an earlier stage. The construction industry is endeavouring to find the highest possible performance in relation to weight and cost. Products of prepainted have the properties that are necessary for industrial production, and offer high flexibility in advanced functions. Increasing numbers of wall structures are being made of steel. Due to the exactness of steel, the structures can be produced offsite and can be assembled more rapidly than traditional timber structures. Facts about future construction 1. Due to the purpose-made advantage of steel, prepainted is more economical than other materials, since production can be made more cost-effective and industrialized. 2. Prepainted has the highest ratio of performance to price. 3. Steel of higher strength will be used in the future for producing prepainted, which will result in thinner and lighter products. 4. Products in prepainted have the properties needed for offsite production and offer good flexibility for production processing. 4

5 Prepainted in the building industry Gutters and downpipes Roofing tiles Composite panels Infill panels and curtain walling panels Long strip roofing Trapezoidal profile frontages and roofing 5

6 Do you want to know more about prepainted? Information from SSAB Tunnplåt The following publications with further information on prepainted are available from SSAB Tunnplåt: Prepainted for buildings, GB837. Inspection and maintenance, GB838. Prelaq No Con Drop, GB821. Use the enclosed coupon to order the information you need. Information from the Swedish Institute of Steel Construction The address of the Institute's comprehensive and interesting web site on the Internet is which includes a great deal of interesting information on steel in construction work. This is where you can find information on the market, design, architecture, project design, production, single-family houses, terraced houses, multi-family houses, building projects, suppliers, a network comprising more than 100 liaison persons, links, research projects, publications, articles, training, seminars, common questions, etc. You can also put questions to the Institute by on info@sbi.se. The Institute has also published many reports focused on steel in construction work and on prepainted sheet. You can order the following reports from the Swedish Institute of Steel Construction, with the exception of Report No. 2, which you would have to order from the Swedish Building Centre. The Prelaq Academy on the Internet The Prelaq Academy is also on the Internet. You can use this as a forum for asking questions and discussing matters with experts and colleagues. But note that you do not have to be on the Internet to use the facilities. You can also ask questions and discuss matters by letter, phone or fax. INTERESTING REPORTS FROM THE SWEDISH INSTITUTE OF STEEL CONSTRUCTION 1. Johan Anderson, Mathias Borg. Recyclability of Light-gauge Steel Studs. Swedish Institute of Steel Construction Report No. 182:10, Stockholm, Price: SEK 90 + VAT. 2. Anna-Brita Krakenberger. Plåt i Arkitekturen (Steel Sheet in Architecture). Swedish Council for Building Research, Stockholm, Price: SEK VAT (from the Swedish Building Centre). 3. Johan Anderson et al. Stålbyggnad (Steel Construction). Swedish Institute of Steel Construction Publication No. 130, Stockholm, Price: SEK VAT. 4. Innovations in Steel. Roofs and Facades around the World. International Iron and Steel Institute, Brussels, Price: SEK 50 + VAT. 5. Johan Anderson, Joakim Widman. Miljö. Fakta om det gröna stålet. (Steel and the environment. Facts about the green steel.) Swedish Institute of Steel Construction Report No. 182:1. Stockholm, Free of charge. 6. Johan Anderson, Joakim Widman. Miljö. Fakta om stål och lättbyggnad. (The environment. Facts about steel framing for housing.) Swedish Institute of Steel Construction Report No. 182:2. Stockholm, Free of charge. 7. Mathias Borg. Livscykelanalys av färgbelagd profilerad byggplåt. (Life cycle assessment of prepainted, profiled structural.) Swedish Institute of Steel Construction Report No. 187:8. Stockholm, Price: SEK VAT. Swedish Institute of Steel Construction P.O. Box 27751, SE Stockholm, Sweden Street address Banérgatan 54, Östermalm, Stockholm Phone , Fax SSAB Tunnplåt AB, SE Borlänge, Sweden. Phone Fax