Spajic d.o.o.

Spajic® steel fibers are concrete reinforcing material which in combination with concrete provides certain advantages in comparison with traditional reinforcement. Spajic® steel fibers are made from different wire materials, designed to provide concrete with temperature and shrinkage crack control, enhanced flexural reinforcement, improved shear strength and increase the crack resistance of concrete. Fibers are sometimes referred to as structural fibers and are intended to carry load and therefore, are used to replace traditional reinforcement in certain non-structural applications as well as minimize and/or eliminate both early and late age crackin

Shot peening is a cold working process used to produce a compressive residual stress layer and modify the mechanical properties of metals. It entails impacting a surface with shot (with a force sufficient to create plastic deformation. Peening a surface spreads it plastically, causing changes in the mechanical properties of the surface. The main benefit of shot peening is the delay or prevention of cracks in highly tensile stressed alloy components. We can alter these undesirable manufacturing and operational tensile stresses to life enhancing residual compressive stresses therefore extending component life. The process works by introducing the residual compressive stress in the surface of the component. The compressive stress helps to prevent crack initiation as cracks cannot propagate in the compressive environment generated by peening. Compressive stresses are generated when the impact of each particle of shot on the component produces a small indentation. It follows that if the surface has been dented, then the material beneath the dent has been compressed. Peening generates not just one dent but many thousands over the surface. Eventually the component becomes encased in a compressively stressed layer. Shot peening is a process specifically designed to enhance the fatigue strength of components which are subject to high alternating stress. Surface treatment procedures like grinding, milling, bending or heat treatment procedures cause Tensile Residual Stress. This Tensile Residual Stress leads to low life cycles of the parts. Shot Peening converts Tensile Residual Stress into Compressive Residual Stress which leads to significant increases in the life cycle of parts and their maximum load capacities.

Descaling is the process of removing oxide deposits from a heat treatment, forging operations, rolling operations pressing operations etc. Scales are formed on a metal surface during heat treatment processes. Oxide scales discolor the metal surface and hinder subsequent finishing operations. Descaling is a metal cleaning process that removes unwanted surface deposits on metals to provide a smooth surface finish. Shot blasting as a descaling method is used on hot rolling items, such as hot rolled metal sheets, steel profiles, metal bars etc.