scholarly journals About transition processes in blasthole drilling at quarries

2020 ◽  
Vol 177 ◽  
pp. 01008
Author(s):  
Andrey Regotunov ◽  
Rudolf Sukhov ◽  
Gennady Bersenyov
Keyword(s):  
Rock Properties ◽  
Repair System ◽  
Drilling Process ◽  
Transition Processes ◽  
Material Resources ◽  
Drilling Performance ◽  
Drilling Method ◽  
Drilling Technology ◽  
Drilling Operations ◽  
Main Transition

As a system, the mining enterprise develops under constantly changing conditions of the external and internal environment. These conditions affect the state of the most important drilling subsystem: blasthole drilling technology, safety, performance, power consumption of the boring rigs and roller bits used. The main transition processes as necessary responses of the subsystem to changing conditions were identified as a result of fragmentary data analysis showing decisions taken over the past 15-20 years, which increase drilling activity efficiency and safety of smaller quarries of Russia, which contain a significant amount of material resources. The main transition processes contribute to the growth of drilling performance and consist of changing the following: bit design for specific rocks; drilling method; drilling mode; boring rig design; controlled parameters of drilling process and rock properties redetermination; parameters of maintenance and repair system. Based on the performed analysis, the systematization results of the main factors predetermining the need for transition processes implementation in the “drilling operations” subsystem were obtained and presented. The proposed approach allowed to reveal a holistic picture of the main interacting factors in the “drilling operations” subsystem. Based on the factors systematization presented in the article it is possible to envisage changes of individual factors depending on changes of other factors, not functionally related directly when planning drilling operations.

scholarly journals Optimization of Hot-Water Drilling in Ice with Near-Bottom Circulation

Water ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 127
Author(s):  
Gaoli Zhao ◽  
Pavel G. Talalay ◽  
Xiaopeng Fan ◽  
Nan Zhang ◽  
Yunchen Liu ◽  
...  
Keyword(s):  
Technology Development ◽  
Hot Water ◽  
Drilling Process ◽  
Outlet Temperature ◽  
Experimental Conditions ◽  
Rate Of Penetration ◽  
Drilling Performance ◽  
Drilling Technology ◽  
Jet Nozzle ◽  
Lower Flow Rate

Hot-water drilling in ice with near-bottom circulation is more advantageous than traditional hot-water drilling with all-over borehole circulation in terms of power consumption and weight. However, the drilling performance of this type of drill has been poorly studied. Initial experiments showed that drilling with single-orifice nozzles did not proceed smoothly. To achieve the best drilling performance, nozzles with different orifice numbers and structures are evaluated in the present study. The testing results show that a single-orifice nozzle with a 3 mm nozzle diameter and a nine-jet nozzle with a forward angle of 35° had the highest rate of penetration (1.7–1.8 m h−1) with 5.6–6.0 kW heating power. However, the nozzles with backward holes ensured a smoother drilling process and a larger borehole, although the rate of penetration was approximately 13% slower. A comparison of the hollow and solid thermal tips showed that under the same experimental conditions, the hollow drill tip had a lower flow rate, higher outlet temperature, and higher rate of penetration. This study provides a prominent reference for drilling performance prediction and drilling technology development of hot-water drilling in ice with near-bottom circulation.

Double-section, non-retrievable casing drilling technique

2012 ◽  
Vol 52 (1) ◽  
pp. 261
Author(s):  
Keith Won ◽  
Ming Zo Tan ◽  
I Made Budi Utamain
Keyword(s):  
Planning Process ◽  
Cost Savings ◽  
Polycrystalline Diamond ◽  
Drilling Process ◽  
Drilling Performance ◽  
First Case ◽  
Drilling Technique ◽  
Drilling Technology ◽  
Improved Design ◽  
Casing Drilling

With the continuous surging in daily rental rates of oilfield exploration rigs, Casing while Drilling technology—which provides operators with an alternative drilling solution for a reduction in drilling flat-time and increased drilling operation efficiency—has appeared to be a standard part of drilling engineers’ toolkit in the well-planning process. Significant cost savings generated by Casing while Drilling have contributed to this technique being widely deployed on top-hole string installations on exploration and appraisal wells in the southeast Asia region. The double-section casing drilling technique has gained increasing popularity among operators in recent years; however, this technique development has been hamstrung by limited casing bit selections. An improved design casing bit has been highly anticipated in the industry to reduce this technique’s complexity of drilling process. Finding an equilibrium between durability and drill-out capability features for a casing bit has been a major challenge for bit designers. The increasing prospect and demand for a double-section casing drilling technique, however, has yielded the development of the casing bit design to a wider portfolio, inclusive of a more robust PDC (polycrystalline diamond compact) cutter-based drillable casing bit. The introduction of the new robust but drillable PDC cutter-based casing bit has broadened the Casing while Drilling application. The double-section casing drilling technique without the need for an additional conventional clean-out trip has become a strong contender to be part of drilling engineers’ next toolkit in delivering enhanced drilling performance and increasing operational efficiencies. This paper will introduce the first case history of the successful planning and implementation of the double-section casing drilling technique—particularly emphasising its optimised drilling performance and ease of drill-out without the need for a specialised drill-out bit.

Drilling Cutting Analysis to Assist Drilling Performance Evaluation in Hard Rock Hole Widening Operation

2020 ◽  
Author(s):  
Daiyan Ahmed ◽  
Yingjian Xiao ◽  
Jeronimo de Moura ◽  
Stephen D. Butt
Keyword(s):  
Performance Enhancement ◽  
Ore Deposits ◽  
Drilling Process ◽  
Rotary Drilling ◽  
Pilot Hole ◽  
Drilling Rig ◽  
Drilling Performance ◽  
Drilling Parameters ◽  
Weight On Bit ◽  
Drilling Operations

Abstract Optimum production from vein-type deposits requires the Narrow Vein Mining (NVM) process where excavation is accomplished by drilling larger diameter holes. To drill into the veins to successfully extract the ore deposits, a conventional rotary drilling rig is mounted on the ground. These operations are generally conducted by drilling a pilot hole in a narrow vein followed by a hole widening operation. Initially, a pilot hole is drilled for exploration purposes, to guide the larger diameter hole and to control the trajectory, and the next step in the excavation is progressed by hole widening operation. Drilling cutting properties, such as particle size distribution, volume, and shape may expose a significant drilling problem or may provide justification for performance enhancement decisions. In this study, a laboratory hole widening drilling process performance was evaluated by drilling cutting analysis. Drill-off Tests (DOT) were conducted in the Drilling Technology Laboratory (DTL) by dint of a Small Drilling Simulator (SDS) to generate the drilling parameters and to collect the cuttings. Different drilling operations were assessed based on Rate of Penetration (ROP), Weight on Bit (WOB), Rotation per Minute (RPM), Mechanical Specific Energy (MSE) and Drilling Efficiency (DE). A conducive schedule for achieving the objectives was developed, in addition to cuttings for further interpretation. A comprehensive study for the hole widening operation was conducted by involving intensive drilling cutting analysis, drilling parameters, and drilling performance leading to recommendations for full-scale drilling operations.

scholarly journals Innovative Double Cathode Configuration for Hybrid ECM + EDM Blue Arc Drilling

2021 ◽  
Author(s):  
Jesus M. Orona-Hinojos
Keyword(s):  
Electrical Discharge Machining ◽  
Removal Rate ◽  
Electrochemical Machining ◽  
Poor Performance ◽  
Electrical Current ◽  
Dielectric Medium ◽  
Drilling Process ◽  
Workpiece Material ◽  
Drilling Technology ◽  
Drilling Operations

Electrical discharge machining is a machining method generally used for machining hard metals, those that would be high cost or have poor performance to machine with other techniques using, e.g., lathes, drills, or conventional machining. Therefore, also known as thermal processes like EDM, Plasma or Laser cutting can be used in drilling operations with poor metallurgical quality on cutting edge and will be necessary complement with other processes such as electrochemical machining (ECM). Both ECM and EDM processes use electrical current under direct-current (DC) voltage to electrically power the material removal rate (MRR) from the workpiece. However in ECM, an electrically conductive liquid or electrolyte is circulated between the electrode(s) and the workpiece for permitting electrochemical dissolution of the workpiece material. While the EDM process, a nonconductive liquid or dielectric is circulated between the cathode and workpiece to permit electrical discharges in the gap there between for removing the workpiece material. Both are principle too different, EC using an electrical conductive and ED using a dielectric medium. But exist a way that can to do a combination of Pulsed EC + ED Simultaneous and allowing the coexist both process, in a semidielectric medium, where both condition exist in the same time, therefore in this hybrid is possible create a tooling device dual cathode for drilling process with promissory advantages fast hole for this innovative hybrid ECDM Simultaneous, this hybrid it’s knew as blue arc drilling technology.

Mathematical Model of the Diamond-Bit Drilling Process and Its Practical Application

1982 ◽  
Vol 22 (06) ◽  
pp. 911-922 ◽  
Author(s):  
Malgorzata B. Ziaja ◽  
Stefan Miska
Keyword(s):  
Penetration Rate ◽  
Drilling Fluid ◽  
Active Surface ◽  
Rock Properties ◽  
Depth Of Cut ◽  
Drilling Process ◽  
Diamond Cutting ◽  
Rate Of Penetration ◽  
Drilling Performance ◽  
Diamond Bit

Abstract With several limiting assumptions, a mathematical model of the diamond-bit drilling, process has been developed. The model represented by an instantaneous rate-of-penetration equation takes into account the reduction in penetration rate during drilling resulting from bit wear. The model has been tested both under laboratory and under field conditions. The comparison of the theoretical and experimental results has shown reasonable agreement. A method for estimating rock properties also has been established. Using this method, we can find the so-called index of rock strength and the index of rock abrasiveness. Introduction Several published studies concerned with diamond-bit drilling report on rock properties and drillability. drilling fluid additives, diamond wear, and drilling performance theories. Among the factors, that affect diamond-bit drilling performance, the type of formation to be drilled is of utmost importance since it significantly affects the type of bit, the drilling practices. and subsequently the rate of penetration and the drilling cost. The nature of the formation is also one of the main factors in planning deep wells, fracture jobs, mud and cement technologies, etc. For rock properties evaluation as well as for selection of proper drilling practices, several descriptions of the diamond-bit drilling process have been developed. The relevant literature is extensive and is not reviewed in this paper. The objective of this paper is to describe the diamondbit drilling model for surface-set diamond core bits and its application to determining the index of formation strength and the index of formation abrasiveness. The main difference between our model and the models known in literature is that we consider the effect of friction between the diamond cutting surfaces and the rock. A decrease in penetration rate is observed if the drilling parameters, are constant and if the formation is macroscopohomogeneous. Drilling Model The drilling model for a surface-set diamond core bit is subjected to the following limiting assumptions.Rock behavior during cutting with a single diamond may be approximated by a rigid Coulomb plastic material.The active surface of the bit is flat, and diamonds are spherical with diameter. d.The cross-sectional area of the chip formed by a single diamond is equal to the diamond cutting surface and can be established by geometry.During drilling, the neighboring diamonds work together to make a uniform depth of cut (Fig. 1).A number of diamonds forming one equivalent blade have to provide it uniform depth of cut from the inner to the outer diameter of the diamond core bit. so the bit is modeled to be a combination of several equivalent blades (Fig. 2).The diamond distribution technique provides uniform radial coverage that results in equally loaded cutting diamonds.Individual cutting diamonds perform some work that results from the friction between the rock and the diamond.Bit wear is assumed to be gradual while drilling is in progress. Under the preceding assumptions we may state that the drilling rate of the surface-set diamond core bit is a function only of weight on bit (WOB), rotary speed, average density of the diamonds on the bit's active surface, diamond size, core-bit diameters, rock properties, and degree of diamond dullness. The effects of flow rate, differential pressure, hydraulic lift, drilling fluid properties. and drillstring dynamics are ignored. According to Peterson, the penetration rate of the diamond bit, after some modifications, can be described by the following simplified equation. (1) This equation does not include the effect of diamond wear and hence pertains to unworn bits or to when bit dullness is negligible. SPEJ P. 911^

The Optimal Process Analysis for Precision-Drilling of Mold Steel SKD61

2007 ◽  
Vol 364-366 ◽  
pp. 649-654
Author(s):  
Wann Yih Lin ◽  
Bean Yin Lee
Keyword(s):  
Taguchi Method ◽  
Process Analysis ◽  
Cutting Parameters ◽  
Processing Parameters ◽  
Cutting Fluid ◽  
Drilling Process ◽  
Drilling Performance ◽  
Optimal Processing ◽  
Drilling Operations ◽  
Optimal Cutting Parameters

The Taguchi method is regarded as a powerful tool to design optimization for quality. In this study, it was used to find the optimal cutting parameters for precision-drilling operations. The cutting parameters include guiding drilling, spindle speed, feed rate, stepping amount, number of steps and cutting fluid. The considered characteristics of performance are tool life, and the variation of drilled hole-diameter. Taguchi Method and Orthogonal Array were applied to the experiments of precision-drilling so as to allocate the corresponding processing parameters. The obtained results were then evaluated by Response Table, Response Chart, and Analysis of Variance methods (ANOVA) to acquire the optimal processing parameters. These were further confirmed by experiment. Finally, the analysis of the precision-drilling process applied for mold steel SKD61 shows that this approach can greatly improve the drilling performance of a small-drilling process.

Analytical and Numerical Modeling of Soil Cutting and Transportation During Auger Drilling Operation

2020 ◽  
Vol 5 (2) ◽  
Author(s):  
Mohamed A. A. Abdeldayem ◽  
Mohamed H. Mabrouk ◽  
Mootaz Abo-Elnor
Keyword(s):  
Numerical Model ◽  
Nonlinear Behavior ◽  
Experimental Results ◽  
Measuring System ◽  
Dominant Factor ◽  
Drilling Process ◽  
Foundation Engineering ◽  
Drilling Operation ◽  
Drilling Performance ◽  
Drilling Operations

Abstract Soil drilling operation has become one of the most important interests to researchers due to its many applications in engineering systems. Auger drilling is one of the ideal methods in many applications such as pile foundation engineering, sampling test for geological, and space sciences. However, the dominant factor in determination of drilling parameters drilling operations experience. Therefore, soil-drilling process using auger drilling is studied to obtain the controlling parameters and to optimize these parameters to improve drilling performance which enables proper selection of machine for a required job. One of the main challenges that faces researchers during using of modeling techniques to define the soil drilling problem is the complex nonlinear behavior of the drilled medium itself due to its discontinuity and heterogeneous formation. This article presents two models that can be used to predict the total resistive forces which affect the auger during soil drilling operations. The first proposed model discusses the problem analytically in a way that depends on empirical data that can be collected from previous experience. The second model discusses the problem numerically with less depending on empirical experienced data. The analytical model is developed using matlab® interface, while the numerical model is developed using discrete element method (DEM) using edem software. A simplified auger drilling machine is built in the soil–tool interaction laboratory, Military Technical College to obtain experimental results that can be used to verify the presented models. Data acquisition measuring system is established to obtain experimental results using a labview® software which enables displaying and recording the measured data collected mainly from transducers planted in the test rig. Both analytical and numerical model results are compared to experimental values to aid in developing the presented parametric study that can be used to define the working parameters during drilling operations in different types of soils. Uncertainty calculations have been applied to ensure the reliability of the models. The combined calculated uncertainty leads to the level of confidence of about 95%.

Analytical and Numerical Modeling of Soil Cutting and Transportation During Auger Drilling Operation

2019 ◽  
Author(s):  
Mohamed A. A. Abdeldayem ◽  
Mohamed H. Mabrouk ◽  
Mootaz Abo-Elnor
Keyword(s):  
Numerical Models ◽  
Experimental Results ◽  
Measuring System ◽  
Dominant Factor ◽  
Drilling Process ◽  
Foundation Engineering ◽  
Nonlinear Behaviour ◽  
Drilling Operation ◽  
Drilling Performance ◽  
Drilling Operations

Abstract Soil drilling operation has become one of the most important interest to researchers due to its many applications in engineering systems. Auger drilling is one of the ideal methods in many applications such as pile foundation engineering, sampling test for geological sciences and space. However, the dominant factor in determination of drilling parameters is real drilling operations experience, which may cause transportation blocking of chips that leads to accidents. As a result, soil drilling process using auger drilling is studied to obtain the controlling parameters and to optimize these parameters to improve drilling performance which enables proper selection of machine for a required job. One of the main challenges that faces researchers during using of modelling techniques to define the soil drilling problem is the complex nonlinear behaviour of the drilled medium itself due to its discontinuity and heterogeneous formation. This paper presents two models that can be used to predict the total resistive forces which affect the auger during soil drilling operation. The first proposed model discusses the problem analytically in a way that depends on empirical data that can be collected from previous experience while the second model discusses the problem numerically with less depending on empirical experienced data. The analytical model is developed using Matlab® interface while the numerical model is developed using discrete element method via EDEM® software. A simplified auger drilling machine is built in the soil-tool interaction laboratory, Military Technical College to obtain experimental results that can be used to verify the presented models. Data acquisition measuring system is established to obtain experimental results using a Labview® program. This program enables displaying and recording the measured data collected mainly from transducers planted in the test rig. Both Analytical and numerical models results are compared to experimental values to aid in developing the presented parametric study that can be used to define the working parameters during drilling operations in different types of soils.

Investigation of Step Micro-Drilling Motion Based on Modeling of High Speed Spindle Driving Axis on Machine Tools Equipped with Vibration-Proof Mechanism

2014 ◽  
Vol 1017 ◽  
pp. 642-647
Author(s):  
Tatsuya Yamashita ◽  
Toshiki Hirogaki ◽  
Eiichi Aoyama ◽  
Ryousuke Shibata ◽  
Keiji Ogawa
Keyword(s):  
High Speed ◽  
Electrical Circuit ◽  
Drilling Process ◽  
Printed Wiring Boards ◽  
Proposed Model ◽  
Drilling Method ◽  
Drilling Technology ◽  
Micro Drilling ◽  
Increasing Demand ◽  
Balance Mechanism

Recently, there has been an increasing demand for miniaturization and multi-functionalization of electronic equipments due to the developments in information technology (IT). Thus, the miniaturization of printed wiring boards (PWBs) and fabrication of highly dense electrical circuit layers are needed to realize the miniaturization and densification of the semiconductor package PWBs. Micro-drilling technology has been attracing attention to machine the electronic micro-through holes with an ultra-high-speed spindle, more than 160 krpm. However, problems have emerged; the drill tool bends and suffers breakage in the drilling process and the heat damage around the drilled hole after a drilling process occurs due to the increase in the drilling aspect ratio between hole depth and diameter. In general, a step feed drilling method is considered an effective way to solve these problems. However, short stroke alternating motion in the spindle axis is needed to do the step drilling process and its motion causes various kinds of vibration. We constructed a machine tool with a novel counter balance mechanism in the spindle driving Z-axis and investigated a model to estimate a proper balance mass for the step drilling process. We compared the frequency response results from a proposed model with the experimental ones, and discussed a control on vibration due to the counter balance mechanism. The results demonstrate that a proposed vibration proof method was found to reduce the vibration in high-speed step-micro-drilling motion and to improve the drilled hole quality and the efficiency of micro-drilling process in the PWB manufacturing fields.

scholarly journals A Force Sensorless Method for CFRP/Ti Stack Interface Detection during Robotic Orbital Drilling Operations

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Qiang Fang ◽  
Ze-Min Pan ◽  
Bing Han ◽  
Shao-Hua Fei ◽  
Guan-Hua Xu ◽  
...  
Keyword(s):  
Cutting Force ◽  
Thrust Force ◽  
Cutting Parameters ◽  
Force Model ◽  
Drilling Process ◽  
Reinforced Plastics ◽  
Orbital Drilling ◽  
Drilling Parameters ◽  
Drilling Operations ◽  
Machining Properties

Drilling carbon fiber reinforced plastics and titanium (CFRP/Ti) stacks is one of the most important activities in aircraft assembly. It is favorable to use different drilling parameters for each layer due to their dissimilar machining properties. However, large aircraft parts with changing profiles lead to variation of thickness along the profiles, which makes it challenging to adapt the cutting parameters for different materials being drilled. This paper proposes a force sensorless method based on cutting force observer for monitoring the thrust force and identifying the drilling material during the drilling process. The cutting force observer, which is the combination of an adaptive disturbance observer and friction force model, is used to estimate the thrust force. An in-process algorithm is developed to monitor the variation of the thrust force for detecting the stack interface between the CFRP and titanium materials. Robotic orbital drilling experiments have been conducted on CFRP/Ti stacks. The estimate error of the cutting force observer was less than 13%, and the stack interface was detected in 0.25 s (or 0.05 mm) before or after the tool transited it. The results show that the proposed method can successfully detect the CFRP/Ti stack interface for the cutting parameters adaptation.

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