The quality brand 
of the KÖNIG steel group comprises the product groups hollow steel sections and steel tubes and is divided into the three areas:
Under our trademark RHS, we set new quality standards in customer service throughout Europe in our core competencies and offer you a comprehensive range of services.
RHS hollow steel sections according to EN 10210 and EN 10219
- Square dimensions: 15x15 mm to 500x500 mm
- Rectangular dimensions: 15x10 mm to 600x400 mm
- EN10210 to 500/300 + 400/400 in wall thicknesses up to 20 mm
- EN10219 to 400/200 + 300/300 in wall thicknesses up to 12.5 mm
Hollow Sections:
Material grades:
S235JRH, S275J2H, S355J2H, S355NH, S420NH, S460NH, stainless steel and various special grades
Your benefits at a glance:
- Largest stock range.
- Fast access to special products and material grades.
- Shortest delivery times thanks to cross-linked logistics.
- Material cuts, bending work, roles and edges.
- Technical advice, training and local seminars in your native language.
In short, RHS is the symbol for highest quality, partnership and reliability.
Our target groups and industries:
- Machine and special machine construction,
- Plant and steel construction,
- Bridge building,
- Vehicle construction,
- Elevators and cable railway construction,
- Agricultural engineering
- Shipbuilding
- Metal construction
What are hollow steel sections?
Hollow steel sections have a rectangular, square or round or oval cross-section. In the defined form, they have the same cross-section over the entire length. Hollow steel profiles are used as a static or structural element in steel structures in particular.
In AluKönigStahl's product range you will find two types of shaped pipes: hot-finished and cold-finished pipes. These differ not only in terms of use, but also in their processing.
Hot finished hollow steel sections according to EN 10210
Thanks to deformation at normalised temperature, hot-finished hollow steel sections have a uniform grain structure and hardness across the entire section cross-section. This also guarantees stable mechanical properties. Hot-finished hollow sections have no hardening in the edge areas (cause of possible crack formation) and for this reason can be welded and hot-dip galvanised without any problems. They also withstand dynamic stresses and low temperatures well.
Extremely small edge radii result in a larger material cross-section. This results in higher static values, more safety (especially in the edge area) and simple, problem-free welded joints.
Areas of application for hot-finished hollow steel profiles
The areas of application for hot-finished hollow steel sections are varied: in mechanical engineering, vehicle construction, lift and cable car construction, in plant construction and agricultural engineering, i.e. everywhere where dynamic stresses are expected, hot-finished hollow steel sections impress with their load-bearing capacity.
We have a large stock of hot-finished hollow steel sections in grades S355J2H and S355NH and can therefore offer you products in many different dimensions. These include rectangular, square, elliptical, oval and semi-oval hollow steel sections. The latter enable architects and steel constructors to design and build creatively with steel. If you compare oval tube constructions with round tube constructions of the same dimensions or statics, they are convincing in many respects. Up to 55 % higher bending strength and a 32 % reduction in face width are just some of the advantages compared to round tube constructions.
The areas of application are versatile and give every building a new and creative design option, whether for column constructions, glass facades, glass roofing or trusses.
Advantages of hot-finished hollow steel profiles
- Top profile properties: Because the mould is given in a heated state, the edge radii are smaller than with cold moulding. This means that a larger bearing surface is formed and thus better static properties. Another advantage is that narrow edge radii offer narrower face widths and thus design advantages.
- Uniform microstructure: Hot-finished hollow steel sections are formed at normalising temperature. As a result, the microstructure (edge and weld area) is uniform across the entire cross-section. They also have a low and uniform hardness in the edge areas, which results in increased flexibility.
- High impact load: Hot-finished hollow steel sections have a high degree of ductility and energy absorption under heavy load. This makes the material resistant to influences such as the weather.
- Good deformability: Cold-finished profiles have reduced deformability, especially in the corner and weld seam areas. Hot-finished profiles, on the other hand, can withstand multiple stresses thanks to an increased degree of ductility.
- Possibility of machining & processing: Due to the low residual stress, hot-finished hollow steel profiles are dimensionally stable. This helps to ensure that no twisting occurs during cutting, welding or other manufacturing processes (e.g. mechanical processing such as milling, planing, drilling). Due to the uniform microstructure in the entire cross-section, no consideration has to be given to the position of the weld seams when drilling. In contrast to cold forming, no special precautions have to be taken when galvanising or welding the edges of hot-formed profiles. Reworking the material is also simplified by the fact that little weld metal and little heat have to be applied. This is due to the fact that the edge radii are narrow and therefore there is less contact surface.
Shaped tubes - cold-formed hollow steel sections according to EN 10219
The main areas of application for cold-formed hollow steel sections are steel construction, metal construction and plant engineering. Whether as a column or truss construction, as a substructure for façades, in hall construction or as a frame construction: the narrow face widths enable attractive aesthetics and good use of space. The straight side surfaces and the good statics of the node connections ensure that the square and rectangular hollow steel profiles can be quickly realised. If the hollow section columns are filled with water or concrete, this ensures a higher load and improved fire protection.
We have a large stock of cold-finished hollow steel sections in grades S355J2H, S275J2H, S235JRH and can therefore offer you the entire range of dimensions.
Differences between hot-formed and cold-formed hollow steel sections
Hot-formed and cold-formed hollow sections differ on various levels. One of them is the area of application: Cold-formed hollow steel profiles are primarily used in steel construction, metal construction and plant engineering.
The area of application of hot-formed hollow steel sections is broader. Dynamic stresses can be expected in each of the following areas of application:
- Mechanical engineering
- Vehicle construction
- Lift and cable car construction
- Plant construction
- Agricultural engineering
Another difference is the distribution of hardness. Due to the production method, the hardness of hot-finished profiles is evenly distributed. In cold-finished profiles, hardness peaks occur at the edges. This results in inhomogeneous strength properties.
There is a similar picture with regard to residual stress. Hot-formed hollow sections have a uniform residual stress. This makes the processing of the surfaces (e.g. welding or galvanising) much easier. With cold-formed profiles, the residual stress is uncontrollable to a high degree.
The absorption of loads and the level of safety are also unequal. Hot-formed hollow sections have larger cross-sectional areas and higher static values. This means that they can take greater loads with the same profile dimensions. This is synonymous with a higher level of safety.
An important measure, especially in the area of structural elements such as columns or frames, is the buckling load. Buckling occurs when the bar reaches that compressive stress at which it loses its stable equilibrium. Hot-finished hollow sections have a higher buckling stress line than cold-finished ones. This means that they can absorb higher buckling loads.
Services
At AluKönigStahl we naturally not only offer the materials themselves, but also individual solutions for our customers. We are constantly developing in order to enable a quick and efficient realisation of our customers' needs. Together with you, we will find the right solution for your project. The following options are currently available:
Perfect shape with 3D tube laser cutting
State-of-the-art 3D tube lasers make it possible for you to get finished square, rectangular and shaped pipes as well as closed and open profiles from a single source. For you, this means shorter production times due to fewer work steps. In addition, there is a reduction in costs for material, production, storage and logistics, as well as improved welding quality due to optimised welding edges. The 3D tube laser gives you a product with optimum fitting accuracy, as individually adjustable positioning and assembly aids are used.
Custom cutting
We are also happy to carry out cutting work on request. Depending on how your shaped tube needs to be shortened or modified, we offer fixed-length cuts as well as single and double mitre cuts. This service guarantees easy material handling in your project. In addition, there are no cost-intensive remnants due to your own cutting.
Bending according to your needs
If your project requires it, you are also welcome to make use of our bending services. Decades of experience in the field of steel forming as well as our extensive machinery for cold and hot bending, rolling and press bending enable rapid processing and very short delivery times. Especially in the areas of steel construction, structural steel engineering, bridge construction and staircase construction, creative and innovative ideas can thus be realised.
Surface treatment with sandblasting
Would you like to free your surfaces from unwanted components? Then we recommend sandblasting. In this process, the surface of the hollow steel sections is freed from rust, scale, dirt or paint by the targeted action of blasting media.
In our core competences, rectangular and square hollow steel sections, high-grade structural steel, steel pipes and piping accessories, we are the best partner for your success.
