Only the best materials
Pulley blocks and other structural parts of a grab experience repeating fluctuating forces which can cause initial cracks and result in failure when not made of the right steel. The upper structure of the Verstegen grabs is made of high tensile structural steel. For most steels, there is a direct correlation between tensile strength and fatigue strength and therefore Verstegen uses high tensile strength (800-1000MPa) for manufacturing the pulley blocks and other structural parts.
The grab shells are in constant contact with the bulk material and therefore the material of the shells must be extremely strong and wear resistant. The shells of all Verstegen grabs are completely made of wear resistant steel with a hardness of 450HB (Hardox , Dillidur) to minimise wear and increase the lifetime of the shells.
Advantages of strong and wear resistant steel
The strength and lifetime of Verstegen grabs is better than with other grabs, because the used steel types are 2-3 times stronger and wear resistant than normal construction steel, S355. Wear and deformation are the most important problems during grabbing operations. The use of wear resistant steel reduces these problems, because of its high strength and resistance. Especially when handling hard and abrasive materials, grabs with shells made of wear resistant steel have large advantages.
Longer lifetime because of less sliding wear
Harder materials, such as iron ore, clinker, sand and aggregagate, rocks are free to slide and roll. By selecting harder steel, service life can be improved considerably. At Verstegen not only the cutting edges, but the complete shells are made of high tensile wear resistant steel.
Less damage and deformation, because of less impact wear
Hard materials hit the surface of the wear component at various angles. A harder grade of steel will deliver a longer service life here as well. Because of the much higher strength of the used steel, our grabs suffer much less denting and deformation than grabs of other manufacturers that use normal construction steel.