Heat transfer simulation in drag–pick cutting of rocks

Loui, John P.; Karanam, U. M. Rao

doi:10.1016/j.tust.2004.08.010

Cited by 24 publications

(9 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…High temperatures, developed on the tool surface (in some cases temperature on the tool surface can reach as much as 550-800 • C, cf. [20,35]) due to heat generated by friction between tool and rock, reduce the hardness of the surface and increase adhesive and abrasive wear.…”

Section: Introductionmentioning

confidence: 99%

“…The results have been compared with experimental measurements showing quite a good performance of the simple numerical model. A two-dimensional transient heat transfer model was developed using the finite element method for the study of temperature rise during continuous drag-cutting by Loui and Karanam [20]. The effect of frictional force and cutting speed on the temperature developed at the pickrock interface was compared with the experimental data.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Discrete element thermomechanical modelling of rock cutting with valuation of tool wear

Rojek

2014

Comp. Part. Mech.

View full text Add to dashboard Cite

The paper presents a thermomechanical discrete element model of rock cutting process. The thermomechanical formulation of the discrete element method considers mechanical and thermal phenomena and their reciprocal influence. The thermal model developed for transient heat conduction problems takes into account conductive heat transfer at the contact between particles and convection on the free surface. The thermal and mechanical problems are coupled by consideration of: (1) heat generated due to friction which is calculated in the mechanical problem and passed to the thermal solution, (2) influence of thermal expansion on mechanical interaction between particles. Estimation of temperature dependent wear has been included into the contact model. The coupled problem is solved using the staggered scheme.The thermomechanical algorithm has been implemented in a discrete element program and applied to simulation of rock cutting with single pick of a dredge cutter head. Numerical results confirm good performance of the developed algorithm.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Discrete element thermomechanical modelling of rock cutting with valuation of tool wear

Rojek

2014

Comp. Part. Mech.

View full text Add to dashboard Cite

show abstract

“…For comparison and verification of the simulation results the input parameters taken are those used for the experimental studies. The details of the experimental studies on rock cutting are given in references Loui (1998) and Loui and Karanam (2005).…”

Section: Drag-cutting Simulationmentioning

confidence: 99%

“…Compressive strength of the rock types has been plotted against the predicted peak cutting force obtained from stability factor contouring model, progressive failure simulation model and experimental observations (Loui and Karanam 2005) for five rock types as given in Fig. 11.…”

Section: Compressive Strengthmentioning

confidence: 99%

Numerical Studies on Chip Formation in Drag-Pick Cutting of Rocks

Loui

Karanam

2011

Geotech Geol Eng

Self Cite

View full text Add to dashboard Cite

A two dimensional non-linear finite element simulation model has been developed using a mathematical model for progressive rock failure for understanding the mode and sequence of rock failure under a drag pick cutter. Rock cutting simulation has also been done using linear elastic modeling using local stability factor contouring. It has been observed from the simulation results that during negative rake angle cutting the chipping occurs by shear failure of the elements. Whereas, in positive rake angle cutting, some elements were observed to fail in shear and some under tension. The predicted peak cutting force using the developed models was found to be up to 25% higher than the experimental values. The effect of input parameters such as rake angle, flank wear, depth of cut and rock properties on the predicted peak cutting force has been studied, verified from earlier experimental studies and compared with some earlier proposed theories on rock cutting. The elastic stress analysis model based on the stability factor contouring method has also been found to be an effective tool to bracket the expected peak cutting force for a given operational and rock parameters but failed to simulate the effect of pick geometry (rake angle) correctly. The non-linear simulation model using progressive rock element failure is superior to elastic linear stress analysis model by simulating the correct trends for all the rock and machining parameters.

show abstract

“…In 1993, Appl et al [113] conducted a series of cutting experiments on granite rock to determine the effects of cutting forces and interfacial temperatures on the life of PDC bits, which are the picks that have a thin layer of diamond (usually 1-2 mm thick) on a tungsten carbide base. It was concluded that the wear rate increased with increasing temperature and the critical temperature To data, a few of analytical studies have been proposed to predict the interface temperature during rock cutting [8,90,155,156]. However, calculating the temperature from these solutions must inevitably suffer from the disadvantage of making major simplifications to the problem; such calculation may not be able to provide accurate predictions of the temperature because of the complicated real-life situation in rock cutting process.…”

Section: Introductionmentioning

confidence: 99%

A study of rock cutting with point attack picks

Shao¹

View full text Add to dashboard Cite

Hard rock mining is currently carried out by drill-and-blast. With the increasing demand for automated, selective and remote mining, the industry hopes to replace conventional drill-and-blast with mechanical excavation. Modern mining machines have sufficient power for cutting hard rocks.The 'bottleneck' which limits the use of mechanical excavation for hard rock mining is the cutting tool wear. Rock cutting tools usually use tungsten carbide (WC) tipped picks. The WC tipped picks are effective and adequate for cutting relatively soft rocks, but unsuitable for hard rocks. To address this issue, CSIRO has developed Super Material Abrasive Resistant Tool (SMART*CUT), aiming at providing an effective cutting tool for hard rock mining. The key feature of the SMART*CUT technology is replacing the conventional WC with thermally stable diamond composite (TSDC) as the cutting tip of the pick. The main advantages of the TSDC tipped picks include (a) good thermal stability, (b) high wear resistance and (c) the ability to mine relatively hard deposits in comparison with the WC tipped picks. The disadvantage of the TSDC tipped picks is their low fracture toughness. To optimise the application of the TSDC tipped picks, this work aimed to improve the understanding of the rock cutting process and mechanisms, in particular to gain a better insight into the interaction between tools and rocks through systematic experimental and numerical studies. The rock cutting processes with the TSDC and WC tipped point attack picks were comprehensively investigated in terms of cutting force, specific energy, tool tip temperature and cutting chips.A study of rock cutting was systematically carried out using the Taguchi method to determine the effects of the cutting parameters on the performance of the TSDC tipped picks. The signal-to-noise (S/N) ratios and the analysis of variance (ANOVA) were applied to investigate the effects of the depth of cut, attack angle, spacing and cutting speed on the mean cutting, normal and bending forces involved in the rock cutting process. The statistical significance of process factors was determined and the optimum parametric combinations were successfully identified. Furthermore, the multiple linear regression (MLR) and artificial neural network (ANN) techniques were adopted to develop the empirical models for predicting the mean cutting and normal forces with the TSDC tipped picks. The established empirical force models showed good predictive capabilities with acceptable accuracy. The ANN models offered better accuracy and less deviation than the MLR models.The pick cutting temperature involved in rock cutting was measured using thermal infrared imaging and embedded thermocouple techniques. The temperature distribution in the cutting area was acquired by using a thermal infrared camera with high speed imaging rates. The results showed that II the TSDC tipped picks generated much lower thermal energy and much fewer sparks than the WC tipped picks. The temperature at the pick tip in the contact area wi...

show abstract

Heat transfer simulation in drag–pick cutting of rocks

Cited by 24 publications

References 8 publications

Discrete element thermomechanical modelling of rock cutting with valuation of tool wear

Discrete element thermomechanical modelling of rock cutting with valuation of tool wear

Numerical Studies on Chip Formation in Drag-Pick Cutting of Rocks

A study of rock cutting with point attack picks

Contact Info

Product

Resources

About