Enhancing the life of shredder hammer tungsten carbide tips
Loughran, J.G., Anderson, S.I., Camuglia, J., and Trapp, N. (2005) Enhancing the life of shredder hammer tungsten carbide tips. In: Proceedings of the 27th Conference of the Australian Society of Sugar Cane Technologists, pp. 508-518. From: 27th Conference of the Australian Society of Sugar Cane Technologists, 3 - 6 May 2005, Bundaberg, QLD, Australia.
PDF (Published Version)
- Published Version
Restricted to Repository staff only
This paper reports on a computational and experimental investigation into the dynamic impact of steel debris against sugar mill shredder hammer tips. During cane preparation, billets of cane are comminuted against tungsten carbide (WC) tips with impact velocities approaching one-third the speed of sound. Foreign debris (often hardened steel pins) in the input stream, result in a high probability of fracture to the WC tiles. During fabrication, the WC tiles are brazed to a mild steel or white iron backing-block using a tri-ply laminate. The laminate is several orders of magnitude less stiff than the WC. Besides acting as a fastener the laminate serves to minimise the build-up of residual stress in the WC due to the marked difference in coefficient of thermal expansion between adjacent materials. The laminate also influences the impedance as compression waves are reflected and refracted. The impact process when steel debris comes into contact with the WC is modelled using explicit finite element dynamics. A Rankine rotating crack model is used to characterise the WC and the projectile is modelled as elasto-plastic. The effect of the WC geometry on resistance to crack initiation is noted and explored numerically. The mechanisms, which dominate failure, are reported. Laboratory experiments confirm the computational modelling. Factory observations involving novel tip geometries at Tully Mill provide evidence of throughputs exceeding 750 000 tonnes of cane between replacements.
|Item Type:||Conference Item (Refereed Research Paper - E1)|
|Keywords:||comminution; damage; FEA; finite element analysis; fractures; shredder-hammer; WC|
|Date Deposited:||07 Nov 2010 23:52|
|FoR Codes:||09 ENGINEERING > 0912 Materials Engineering > 091202 Composite and Hybrid Materials @ 40%
09 ENGINEERING > 0915 Interdisciplinary Engineering > 091599 Interdisciplinary Engineering not elsewhere classified @ 40%
09 ENGINEERING > 0903 Biomedical Engineering > 090301 Biomaterials @ 20%
|SEO Codes:||87 CONSTRUCTION > 8703 Construction Materials Performance and Processes > 870302 Metals (e.g. Composites, Coatings, Bonding) @ 50%
86 MANUFACTURING > 8613 Transport Equipment > 861301 Aerospace Equipment @ 30%
87 CONSTRUCTION > 8799 Other Construction > 879999 Construction not elsewhere classified @ 20%