scholarly journals An Analytical Model for Rock Cutting with a Chisel Pick of the Cutter Suction Dredger

2020 ◽  
Vol 8 (10) ◽  
pp. 806
Author(s):  
Yiping Ouyang ◽  
Qi Yang ◽  
Xinquan Chen ◽  
Yongfu Xu
Keyword(s):  
Cutting Force ◽  
Analytical Model ◽  
Cutting Parameters ◽  
Theoretical Models ◽  
Rock Cutting ◽  
Rake Angle ◽  
Experimental Results ◽  
Tensile Failure ◽  
Cavity Expansion Theory ◽  
Sidewall Effect

Cutter suction dredgers are important pieces of rock excavation equipment in port and waterway construction. It is valuable but difficult to properly estimate the cutting force on the chisel pick of the cutter suction dredger. In this paper, an analytical model, called the crushed zone expansion induced tensile failure model (CEIT model), is proposed for rock cutting with a chisel pick in order to predict the peak cutting force (Fc) more accurately. First, a review of the existing models for rock cutting with a chisel pick is presented. Next, based on the tensile breakage theory, cavity expansion theory and some hypotheses, the mathematical formula of the CEIT model is obtained. Different from that in the previous models, the effect of the rock on both sides of the chisel pick on Fc, defined as the sidewall effect is considered in the CEIT model. Then, the predicted Fc by the CEIT model is compared with the predicted Fc by existing theoretical models and experimental results to check the validity of the CEIT model. The results show that the CEIT model can well capture the relationships of Fc to the cutting parameters, including cutting width, cutting depth, and rake angle, and can predict the experimental results much better than the existing models. Finally, the sidewall effect and its influence factors according to the CEIT model are discussed.

scholarly journals A study on the influence of pick geometry on rock cutting based on full-scale cutting test and simulation

2020 ◽  
Vol 12 (12) ◽  
pp. 168781402097449
Author(s):  
Xuefeng Li
Keyword(s):  
Shear Failure ◽  
Cutting Parameters ◽  
Rock Cutting ◽  
Rake Angle ◽  
Full Scale ◽  
Cutting Performance ◽  
Tensile Failure ◽  
General Process ◽  
Multiple Attribute ◽  
Cutting Simulations

In this paper, series of full-scale cutting tests and cutting simulations are carried out to investigate the influence of installation parameter and geometry of the pick on cutting performance. The discrete element method is used to simulate the rock cutting process. A general process to calibrate macro properties of rock including uniaxial compressive strength (UCS), elastic modulus, Poisson’s ratio, cohesion and internal friction angle is proposed and used to complete the calibration of coal model. The cutting simulations are performed using picks with different tip angles and rake angles. The results show that the peak cutting force (PCF) decreases with the increase of rake angle following an inverse proportional function when the rake angle is positive, while it varies following a parabolic curve in the condition of negative rake angle. Moreover, the crack mode changes from primarily shear failure to primarily tensile failure with the increase of rake angle. Finally, a multiple-attribute index is proposed to evaluate the cutting performance and select the optimum cutting parameters.

scholarly journals Investigation of the influence mechanism of rock damage on rock fragmentation and cutting performance by the discrete element method

2019 ◽  
Vol 6 (5) ◽  
pp. 190116 ◽  
Author(s):  
Si-fei Liu ◽  
Shuai-feng Lu ◽  
Zhi-jun Wan ◽  
Jing-yi Cheng
Keyword(s):  
Cutting Force ◽  
Rock Cutting ◽  
Rock Breaking ◽  
Pulse Number ◽  
Rock Fragmentation ◽  
Cutting Performance ◽  
Tensile Failure ◽  
Rock Damage ◽  
Damage Factor ◽  
Mining Machinery

Rock damage is one of the key factors in the design and model choice of mining machinery. In this paper, the influence of rock damage on rock fragmentation and cutting performance was studied using PFC 2D . In PFC 2D software, it is feasible to get rock models with different damage factors by reducing the effective modulus, tensile and shear strength of bond by using the proportional factors. A linear relationship was obtained between the proportion factor and damage factor. Furthermore, numerical simulations of rock cutting with different damage factors were carried out. The results show that with the increase of damage factor, the rock cutting failure mode changes from tensile failure to brittle failure, accompanied by the propagation of macro cracks, the formation of large debris and a notable decrease in the peak cutting force. The mean cutting force is negatively correlated with the damage factor. Besides this, the instability of cutting force was evaluated by the fluctuation index and the pulse number of unit displacement. It was found that the cutting force was quite stable when the damage factor was 0.3, which improves the reliability of cutting machines. Finally, the cutting energy consumption of rock cutting with different damage factors was analysed. The results reveal that an increase of damage factor can raise the rock cutting efficiency. The aforementioned findings play a significant role in the development of assisted rock-breaking technologies and the design of cutting head layout of mining machinery.

A Study of Relation between Roundness and Cutting Force in CNC Turning Process

2015 ◽  
Vol 799-800 ◽  
pp. 366-371 ◽  
Author(s):  
Deuanphan Chanthana ◽  
Somkiat Tangjitsitcharoen
Keyword(s):  
Cutting Force ◽  
Cutting Forces ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Rake Angle ◽  
Turning Process ◽  
Nose Radius ◽  
Cnc Turning ◽  
Cnc Turning Process ◽  
Tool Nose Radius

The roundness is one of the most important criteria to accept the mechanical parts in the CNC turning process. The relations of the roundness, the cutting conditions and the cutting forces in CNC turning is hence studied in this research. The dynamometer is installed on the turret of the CNC turning machine to measure the in-process cutting force signals. The cutting parameters are investigated to analyze the effects of them on the roundness which are the cutting speed, the feed rate, the depth of cut, the tool nose radius and the rake angle. The experimentally obtained results showed that the better roundness is obtained with an increase in cutting speed, tool nose radius and rake angle. The relation between the cutting parameters and the roundness can be explained by the in-process cutting forces. It is understood that the roundness can be monitored by using the in-process cutting forces.

Study on the Effect of Rake Angle on Cutting Forces in Ultra-Precision Machining

2012 ◽  
Vol 516 ◽  
pp. 551-556
Author(s):  
Thanh Hung Duong ◽  
Kim Huyn Chul ◽  
Lee Dong Yoon
Keyword(s):  
Theoretical Analysis ◽  
Cutting Force ◽  
Electroless Nickel ◽  
Cutting Parameters ◽  
Rake Angle ◽  
Precision Machining ◽  
Reported Study ◽  
Ultra Precision ◽  
The Relationship ◽  
Cutting Speeds

In recent years, there have been many studies concerning the effect of cutting parameters and tool parameters on the ultra precision machining of electroless nickel. However, there is no known reported study on the relationship between the cutting force and tool rake angle in ultra precision machining of electroless nickel. The objective of this study is to compare and investigate the cutting force with various rake angles for micro machining electroless nickel work pieces by theoretical analysis and experiment. Diamond tools with rake angles of-10o, 0o and 10o were used in the experiment. According to theoretical analysis, the tool with a 10o rake angle induces the smallest cutting force. However, the experiment showed that the tool with zero rake angle always gave us the smallest cutting force for all cutting speeds, cutting depths and pattern pitches.

scholarly journals Numerical Investigation of the Rock Cutting Performance of a Circular Sawblade

2020 ◽  
Vol 2020 ◽  
pp. 1-18
Author(s):  
Zhiwen Wang ◽  
Qingliang Zeng ◽  
Zhenguo Lu ◽  
Zhihai Liu ◽  
Xu Li
Keyword(s):  
Cutting Force ◽  
Great Influence ◽  
Cutting Parameters ◽  
Simulation Method ◽  
Rock Cutting ◽  
Rock Breaking ◽  
Feed Speed ◽  
Specific Cutting Energy ◽  
Cutting Depth ◽  
Cutting Energy

The rock cutting process with a circular sawblade and the rock breaking mechanism of rock are studied with a numerical simulation method in this paper. The influence of cutting parameters of the circular sawblade on cutting force, rock damage, and specific cutting energy in the process of circular sawblade cutting rock is researched. The cutting force increases with the feed speed and an increase in cutting depth and decline in rotation speed. Cutting rock with double circular sawblades can reduce cutting force. However, the specific cutting energy declines with the increase in cutting depth and the decline in the distance between the double circular sawblades. Cutting parameters have a great influence on the damage range of rock. The research results can be applied to rock processing with a circular sawblade.

Influence of Rock Mechanical Properties on the Formation of Rock Fragments During Cutting Operation

2011 ◽  
Author(s):  
Pradeep L. Menezes ◽  
Michael R. Lovell
Keyword(s):  
Mechanical Properties ◽  
Cutting Forces ◽  
Numerical Models ◽  
Cutting Parameters ◽  
Rock Cutting ◽  
Rake Angle ◽  
Rock Fragmentation ◽  
Oil Well ◽  
Explicit Finite Element ◽  
Rock Mechanical Properties

Mechanical rock cutting is a process encountered in different engineering applications including rock excavation, mining and deep oil well drilling. Rock mechanical properties vary with depth in the subsurface and also at different geographical locations due to different environmental conditions. Understanding of fragmentation mechanisms in specific rock materials allows the determination of optimum cutting parameters that improve cutting efficiency and increase tool life during cutting operations. In the present investigation, numerical models that accurately predict the rock fragmentation and stress profiles in the rock slab during cutting were developed using the explicit finite-element method (FEM). In the numerical models, a damage material model was utilized to capture the rock fragmentation process and a rigid steel cutter (at different rake angles) was displaced at different velocities against a stationary rock slab. Rock slabs with significantly different mechanical properties were incorporated with a constant friction factor and a cutting depth of 1 mm. The variation of cutting forces and stresses, and fragmentation of the rock slab were analyzed. The simulation results indicated that the explicit FEM is a powerful tool for simulating rock cutting as the formation of fragments were distinctly observed at different cutting conditions. The rock mechanical properties and tool rake angle were found to have the most significant effect on the rock fragmentation during cutting operations. The cutting forces were also influenced by mechanical properties of the rock and tool rake angle.

Determination of Cutting Forces for Micro Milling

2008 ◽  
Author(s):  
Shih-Ming Wang ◽  
Zou-Sung Chiang ◽  
Da-Fun Chen
Keyword(s):  
Cutting Force ◽  
Chip Thickness ◽  
Cutting Parameters ◽  
Rake Angle ◽  
Micro Milling ◽  
Force Model ◽  
Machining Parameters ◽  
Cutting Force Model ◽  
Optimal Cutting Parameters

To enhance the implementation of micro milling, it is necessary to clearly understand the dynamic characteristics of micro milling so that proper machining parameters can be used to meet the requirements of application. By taking the effect of minimum chip thickness and rake angle into account, a new cutting force model of micro-milling which is function the instantaneous cutting area and machining coefficients was developed. According to the instantaneous rotation trajectory of cutting edge, the cutting area projected to xy-plane was determined by rectangular integral method, and used to solve the instantaneous cutting area. After the machining coefficients were solved, the cutting force of micro-milling for different radial depths of cut and different axial depths of cut can be predicted. The results of micro-milling experimental have shown that the force model can predict the cutting force accurately by which the optimal cutting parameters can be selected for micro-milling application.

scholarly journals Accurate Modeling of Working Normal Rake Angles and Working Inclination Angles of Active Cutting Edges and Application in Cutting Force Prediction

Micromachines ◽  
2021 ◽  
Vol 12 (10) ◽  
pp. 1207
Author(s):  
Peng Li ◽  
Zhiyong Chang
Keyword(s):  
Cutting Force ◽  
High Performance ◽  
Cutting Parameters ◽  
Rake Angle ◽  
Cutting Edge ◽  
Cutting Force Prediction ◽  
Force Prediction ◽  
Inclination Angles ◽  
Cutting Velocity ◽  
Differential Element

The normal Rake angle is an important geometric parameter of a turning tool, and it directly affects the accuracy of the cutting force prediction. In this study, an accurate model of the working normal rake angle (WNRA) and working inclination angle (WIA) is presented, including variation in the cutting velocity direction. The active cutting edge of the turning tool is discretized into differential elements. Based on the geometric size of the workpiece and the position of the differential elements, the cutting velocity direction of each differential element is calculated, and analytical expressions for the WNRA, WIA, and working side cutting edge angle are obtained for each differential element. The size of the workpiece is found to exert an effect on the WNRA and WIA of the turning tool. The WNRA and WIA are used to predict the cutting force. A good agreement between the predicted and experimental results from a series of turning experiments on GH4169 with different cutting parameters (cutting depth and feed rate) demonstrates that the proposed model is accurate and effective. This research provides theoretical guidelines for high-performance machining.

Experimental Investigation on Cutting Performance of Face Milling Cutter

2012 ◽  
Vol 217-219 ◽  
pp. 2133-2137
Author(s):  
Bing Yan ◽  
Yang Li ◽  
Wei Wang ◽  
Hao Feng
Keyword(s):  
Cutting Force ◽  
High Speed ◽  
Cutting Parameters ◽  
Rake Angle ◽  
Tool Geometry ◽  
Depth Of Cut ◽  
Machined Surface ◽  
High Speed Cutting ◽  
Angle Effect ◽  
Axial Depth

The cutting tool geometry and cutting parameters have a great impact on cutting force, while cutting force is an important factor which affecting the tool life. High speed cutting experiments have shown that when slight axial depth of cut is adopted, rake angle effect on main cutting force significantly. When cutting aluminum alloy, the roughness of machined surface decrease with increasing tool rake angle. The axial depth of cut does not have a big influence on machined surface ’s roughness.

An Experimental Study of Orthogonal Cutting of SiCp/Al Composites: Cutting Forces Analysis

2012 ◽  
Vol 500 ◽  
pp. 230-235
Author(s):  
Shu Tao Huang ◽  
Li Zhou ◽  
Jin Lei Wang
Keyword(s):  
Cutting Force ◽  
Orthogonal Cutting ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Rake Angle ◽  
Mechanical And Thermal Properties ◽  
Cutting Depth ◽  
Metal Parts ◽  
Orthogonal Machining ◽  
Rapid Tool

Due to the superior mechanical and thermal properties of SiCp/Al composites, their poor machinability has been the main deterrent to their substitution for metal parts. Machining of SiCp/Al composites has been considerably difficult because the extremely abrasive nature of SiC reinforcements causes rapid tool wear. In this paper, an experiment was carried out to investigate the influence of the cutting speed, cutting depth and tool rake angle on cutting force during orthogonal machining of SiCp/Al composites. The results indicate that the cutting depth is one of the main cutting parameters that affect the cutting force, while the cutting speed and tool rake angle have no significant effects on the cutting force.

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