Ruukki - It’s the Smart Choice with Special Steels
Ruukki, a Finland-based steel manufacturer with an annual steel production capacity of 2.3 million tons, operates in some 30 countries and employs around 9,000 people. With headquarters and steel mill in Finland, Ruukki offers high-quality solutions to its customers. The company aims to grow through accelerating its global sales of special steels. Ruukki has pursued a fast growth course in the Turkish market, which entered in 2009 with an office of its own. In Turkey Ruukki is focusing on sales of special steels, such as high-strength Optim and wear-resistant Raex and Ramor protection steels, which are manufactured by direct quenching method developed by Ruukki. We also offer customers technical support in order to increase the competitiveness of their products.
With stockyard of 1,200 square meters in Mersin, Ruukki eased the burden on its solution partners in Turkey in terms of work, time and cost. The company will continue expanding with new stockyards and district offices in different regions across Turkey. Ruukki has achieved growth annually in Turkey. Turkey has been a significant production base in trailer, crane and defense industries recently, so there is a demand also for Ruukki’s special steels.
Ruukki Ramor – a family of advanced protection steels
Ruukki’s range of special steels includes Ramor, a quenched protection steel which has been in production since 2001 and is available in three hardness classes 550, 500 and 400 HBW. Ramor solutions are mostly used for armoured vehicles, doors, window frames and systems for transporting and safekeeping money.
The range of Ramor protection steels was recently expanded with Ramor 550 grade designed for ballistic protection. New Ramor 550 is six times harder and stronger than mild steel. Designed for applications requiring protection against explosions or ballistic threats, Ramor protection steels combine excellent ballistic properties with hardness and high strength. Ramor 550 protection steel is well suited for armoured vehicles, military vehicles and equipment, safe rooms and other applications where structural weight saving is required.
Both the new Ramor 550 grade and Ramor 500 grade are the most appropriate alternative when protection is needed against kinetic energy projectiles, i.e. ballistic performance. The Ramor 400 grade is designed to give protection against high pressures caused by explosions and blasts. Ramor also offers the best solutions for products where the weight of the steel structure is a significant factor especially in mobile applications. Weight reduction of 10-20 % can be achieved by using the new Ramor 550 grade.
All important workshop properties of Ramor 500 and the new 550 grade
Ramor steels have excellent surface quality, flatness and dimensional accuracy, together with good cutting, bending and welding properties. They can be welded using all conventional welding methods. Ramor 550 has the best workshop properties in its hardness class and has as good workability as Ramor 500.
The workshop process typically starts with cutting. Laser cutting is the most common method, but also plasma and water jet cutting can be used. A low level of residual stress combined with minimal dimensional variation from batch to batch ensures economical parts processing. Machining operations such as drilling and even threading can be done with modern hard metal tools.
The next phase in parts production is bending, which is a very effective way to produce accurate ballistically sound parts. The bending radius guarantee for Ramor is 6 times the thickness in all directions. In certain customer projects, significantly tighter radiuses are used. If tighter radiuses are used, preliminary tests are recommended to find the right parameters. As narrow an opening width as power allows is usually recommended because this reduces the springback effect and the end result is a dimensionally accurate part.
Ready-made parts must be joined together. This is most often done by welding. Ramor 500 can usually be welded without preheating, a factor that reduces welding time and cost dramatically. Both ferritic and austenitic consumables can be used with good success.
Wide range of advantages through direct quenching
Ruukki uses its own direct quenching process where the product is hardened i.e. quenched directly at the rolling mill. Ramor has a fully martensitic microstructure and is given the desired structure through a unique process. Ruukki’s direct quenching process combines thermomechanical rolling features such as controlled austenite grain size with carefully adjusted rapid cooling immediately after rolling.
Ruukki certifies Ramor plates according to widely-recognised test standards (EN 1522, VPAM 2007, Stanag 4569 both KE and FSP). Multihit capability is one of the main benefits of steel armour and Ramor is a very good example of this. Multihit testing involves three shots being fired very close to each other. This puts steel toughness to the ultimate test. The environment is another factor that must be taken into consideration during ballistic testing. Ramor has been successfully tested in Arctic temperatures of -50°C and desert temperatures of +70°C.
We are committed to continuously improv the energy efficiency in our own operations like in our steel production. Ruukki ranks among the most energy-efficient in the world in iron-making and uses nearly the minimum amount of coking coal possible using current technology.
