Why HARDOX in tipping trailers? 1. Higher elastic limit and higher ultimate stress 2. Longer life span (higher resistance to deformation, abrasion and scratching) 3. Excellent resistance to impact 4. Less lateral reinforcements needed = less welds = less corrosion and cracking risks 5. Less lateral reinforcements needed = lower empty weight and better air resistance = less consumption Editor: Johan Anderson. Date: 08/01/07. Version: uk 02. Page 1
Specifications of HARDOX / regular steel Specifications of HARDOX / regular steel Elastic limit Ultimate stress Steel type Hardness (Brinell) Resilience (J at C) (kg/mm²) (kg/mm²) S235 or St 37-2 (regular steel) 23,5 40 120 27 J at 0 C S355 or St 52-3 (regular steel) 35,5 48 170 27 at 0 C S42 0 (Joskin high tensile steel) 42 55 210 40J at -20 C HARDOX 450 (KTP HARDOX) 120 140 450 40J at -40 C The elastic limit is the strain from which a material starts to deform irreversibly. The ultimate stress is the strain from which a material breaks. The hardness of a given steel type is its capacity to resist to deformation, abrasion and scratching. The resilience is the energy required to break a material (J/50mm²). One Joule (J) corresponds to a 0,1 kg mass working on a 1 m distance. Editor: Johan Anderson. Date: 08/01/07. Version: uk 02. Page 2
Higher elastic limit and higher ultimate stress The elastic limit of HARDOX 400 is 2,5 to 4 times higher than that of regular steel. The elastic limit of HARDOX 450 is 3 times higher than that of S420, the high tensile steel initially used by JOSKIN. x HARDOX 400 Stress [N/mm 2] x St 52-3 Regular steel weight HARDOX 400 weight Elongation [%] Editor: Johan Anderson. Date: 08/01/07. Version: uk 02. Page 3
Longer life span The hardness of HARDOX 450 amounts to 450 Brinell. The hardness of regular steel varies between 120 and 170 Brinell. The life span of HARDOX 400 is 2 to 3 times longer than for regular steel, the plate thickness being unchanged. The life span of HARDOX 450 is still increased by 60 % on average in relation to HARDOX 400. Life span Resistance to wear of HARDOX steel Regular steel HARDOX 400 Editor: Johan Anderson. Date: 08/01/07. Version: uk 02. Page 4
Excellent resistance to impact 0 p [mm] 10 20 HARDOX 400 WELDOX 700 S 355 m = 500 kg r = 100 mm 30 40 Plate thickness t = 16 mm h = 2.82 m The graph above shows the maximum deformation (in mm) of several steel types subjected to the impact of a 500 kg mass, which is dropped on 2,82 m height and supported by a 314 cm² plate surface. Note that the maximum deformation is 33 mm for S355 steel and merely 12 mm for HARDOX400. Following the impact, the HARDOX400 keeps a 7 mm deformation vs 15 mm for S355 steel. Editor: Johan Anderson. Date: 08/01/07. Version: uk 02. Page 5
Excellent resistance to impact In practice, a tipping trailer in HARDOX offers, on average, 50 to 60 % less risks of plastic deformation by the clamps than a tipping trailer in regular steel. Regular steel HARDOX 400 Editor: Johan Anderson. Date: 08/01/07. Version: uk 02. Page 6
Less lateal reinforcements needed Because of its low elastic limit, the regular steel requires reinforcements that are close to each other. The elastic limit of HARDOX steel is 3 times higher than that of S420 steel. The distance between the lateral reinforcements can therefore be increased with no deformation risk of the lateral walls. Thanks to its high elastic limit, the HARDOX steel is able to work freely and strainless. Editor: Johan Anderson. Date: 08/01/07. Version: uk 02. Page 7
Less lateral reinforcements needed It emerges from an independent study led by Lars Drugge (vehicle expert and scientist), from the Royal Institute of Technology (KTH) in Stockholm, that : In the best air resistance conditions, the fuel consumption can be reduced by 10 %. A study of the University of Huddersfield (published in the Transport Engineer of August 1999) shows that reducing the number of lateral reinforcements of course leads to a lower empty weight but mainly reduces the fuel consumption by 7 to 10 %. ****************************** Last point to be highlighted: Any tipping trailer is a working tool subjected to several wearing phenomena, and the welds are particularly weak points in this respect (corrosion, cracks,...). Limiting the number of welds as much as possible therefore means highly preventing your tipping trailer from wearing prematurely. Editor: Johan Anderson. Date: 08/01/07. Version: uk 02. Page 8