scholarly journals INTERACTION OF A HELICAL BLADE OF A DRILLING TOOL WITH FROZEN GROUND

2020 ◽  
Vol 17 (2) ◽  
pp. 162-171
Author(s):  
I. G. Martiuchenko ◽  
M. I. Zenin
Keyword(s):  
Experimental Studies ◽  
Frozen Soil ◽  
Borehole Diameter ◽  
Drilling Process ◽  
Frozen Ground ◽  
Drilling Tool ◽  
Drilling Tools ◽  
Permafrost Soils ◽  
Helical Blade ◽  
Soil Destruction

Introduction. Drilling of frozen and permafrost soils is one of the most complicated and energy-intensive processes of earthworks. The current drilling tools are not efficient enough to use since they implement energy-intensive drilling processes and are not always suitable for various types of soil. The use of helical working elements that implement the process of soil destruction with less energy-intensive types of deformations is advanced. The purpose of the research is to study the interaction of a helical blade of a drilling tool with frozen soil.Materials and methods. The article covers a method for conducting experimental studies of the interaction of a helical blade of a drilling tool with frozen ground and the tested models of the drilling tool. The influence of geometric parameters of a helical drill on a borehole formation process is studied.Results. The experimental research proved the hypothesis about the possibility of implementing a drilling process with tearing strain and obtaining a borehole diameter larger than a diameter of a destructive section of a helical blade. The dependence of the destroyed soil volume and the relation of an obtained borehole diameter to a diameter of a destroying section of a helical blade according to the angle of bend of a helical blade radius at which its increment occurs is determined.Discussions and conclusion. It is established that a helical drilling tool performs a borehole drilling due to the tearing strain implementation, which makes it possible to achieve more efficient drilling and obtain a borehole diameter larger than a diameter of the destroying section of a helical blade.Financial transparency: the authors have no financial interest in the presented materials or methods. There is no conflict of interest.

scholarly journals Сomparative analysis of efficiency of use a screw drill on frozen soil

2021 ◽  
Vol 18 (2) ◽  
pp. 160-167
Author(s):  
I. G. Martiuchenko ◽  
M. I. Zenin
Keyword(s):  
Comparative Analysis ◽  
Shear Deformation ◽  
Frozen Soil ◽  
Drilling Process ◽  
Action Current ◽  
Drilling Tool ◽  
Drilling Tools ◽  
Permafrost Soils ◽  
Soil Destruction ◽  
Technical And Economic Indicators

Introduction. Drilling of frozen and permafrost soils is one of the complex and energy-intensive processes of earthworks. Drilling tools used on frozen soils implement the process of drilling the soil by deformation of cutting or crushing action. Current drilling tools are not efficient enough to use because they implement energy-intensive drilling processes and are not always suitable for various types of soils. A screw drill is considered, which implements the process of soil destruction by shear and shear deformation, which is less energy intensive.Materials and methods. On the basis of theoretical studies of the interaction of 3 types of drilling tools with frozen soil, a comparative analysis was carried out to determine the efficiency of a screw drill use. The technical and economic indicators of the drilling process were compared. A method for determining the efficiency of the use a screw drill based on the analysis of special target functions is presented.Results. The results of a comparative analysis of drilling tools have been obtained. Depending on the nature of soil deformation, the effectiveness of one drilling tool over another is determined. As a result of a comparative analysis of the drilling speed and the energy intensity of the drilling process, the efficiency of the screw drill was established.Discussions and conclusion. In the course of the comparative analysis, the efficiency of the screw drill was determied, which implements shear deformation and soil separation, justifying the feasibility of further research.

scholarly journals Experimental Studies of Drilling Tools Magnetic Catchers with the Parallel Connection of Permanent Magnets

2019 ◽  
Vol 297 ◽  
pp. 03005
Author(s):  
Mikhail. Kobylyansky ◽  
Aleksey Ermolaev ◽  
Dmitriy Kobylyansky
Keyword(s):  
Rare Earth ◽  
Permanent Magnets ◽  
Magnetic System ◽  
Experimental Studies ◽  
Calculated Data ◽  
Parallel Connection ◽  
Drilling Tool ◽  
Magnetic Parameters ◽  
Magnetic Cores ◽  
Drilling Tools

The article presents the results of bench and industrial tests of drilling tools magnetic catchers with the parallel connection of permanent magnets. The catchers are developed on the basis of optimization studies of the mathematical model of the U-shaped magnetic system. The catchers on ferrite-barium magnets with U-shaped magnetic systems showed very low characteristics. The catcher with unshielded magnetic system also showed low power and magnetic parameters. Production tests of such a catcher in a real iron ore well demonstrated its unsuitability for the extraction of the drilling tool elements. Laboratory studies of a magnetic catcher with the shielded U-shaped magnetic system on powerful rare earth magnets have shown that it has high power and magnetic parameters. Its industrial tests in the mine showed high efficiency of the extraction of the drilling tool broken off elements, in particular, crowns and pneumatic hammers. A catcher with the parallel connection of rare-earth magnets with step-shaped magnetic cores was also studied. It has even higher characteristics. The use of step magnetic cores allows to reduce the consumption of magnetic materials by a third. The best results were shown by a catcher with a quadruply connected magnetic system made according to the cruciform configuration on rare earth magnets. The results of the experimental studies well agree with the calculated data, the difference is 10-20%.

Experimental Studies of Pipeline Uplift Resistance in Frozen Ground

2004 ◽  
Author(s):  
Bill Liu ◽  
Jack Crooks ◽  
J. F. (Derick) Nixon ◽  
Joe Zhou
Keyword(s):  
Experimental Studies ◽  
Soil Surface ◽  
Mechanical Tests ◽  
Frozen Soil ◽  
Frost Heave ◽  
Frozen Ground ◽  
Frozen Soils ◽  
Uplift Resistance ◽  
Load Displacement ◽  
The Impact

A buried pipeline is subject to a variety of internal and external loads, one of which is the load induced by relative movements between the pipeline and the surrounding soils. Frost heave is one of the potential mechanisms that induce the relative movement for buried pipelines of chilled gas. The magnitude of the loads due to frost heave depends upon the amount of heaving and the load-displacement characteristics of the surrounding frozen soils, i.e., the uplift resistance of the frozen soils. Under the sponsorship of Pipeline Research Council International (PRCI), laboratory uplift tests have been carried out to study the load-displacement characteristics of a frozen soil and to assess the impact of loading rate, ice content and freezing direction. In addition to the measurements of the load and displacement of the pipe, deformations of the soil surface were also monitored at various locations. Parallel to the uplift tests, a series of laboratory geo-mechanical tests were conducted to define stiffness, tensile strain limits and time-dependent behavior of the frozen soil. Examples of the uplift test results are presented in the paper, together with detailed descriptions of soil material and test conditions. It is noted that quantitative data on uplift resistance are considered proprietary and will not be presented in this paper; however, detailed data may be obtained from technical publications of PRCI. Observations during the test with respect to the development of cracks in the frozen soil will be discussed. The load-displacement relationships measured in the uplift tests, together with the geo-mechanical properties of the frozen soil, will be used to the development and calibration of a numerical model, which will be presented in a separate technical paper to IPC2004.

Analysis of the High Performance Drilling Process: Influence of Shape and Profile of the Cutting Edge of Twist Drills

2008 ◽  
Vol 130 (5) ◽  
Author(s):  
W. Koehler
Keyword(s):  
High Performance ◽  
Experimental Methods ◽  
Cutting Edge ◽  
Drilling Process ◽  
Drilling Tool ◽  
Drilling Tools ◽  
Tool Edge ◽  
Edge Profile ◽  
Twist Drills ◽  
Made In

The aims of the investigations presented in this paper were to measure the tool load under conditions of high performance drilling and to analyze if changes of the tool edge shape as well as the edge profile significantly influence the edge stresses. The described methods to analyze the influences of edge shape modifications will contribute to the optimization of drilling tools. Based on a specific cutting edge shape of a drilling tool, systematic changes to the tool’s chamfer and the transition from the chisel edge to the cutting edge were made. Forces and temperatures on the cutting edge were measured as well as the heat flow into the chips and the workpiece. Using a quick-stop device, chip roots of the different drill tools under conditions of high performance machining were made in order to analyze the chip formation. The contact between chip and rake face could be made visible by a so called contact area analysis. It could be shown that the modification of the transition from the chisel to the cutting edge influences the orientation of the forces on the drill. Machining with a rounded cutting edge shape compared to a chamfered edge reduces the mechanical and thermal tool load. This is confirmed by the fact that the deformation zone in front of the cutting edge is smaller as shown by the crosssections of the chip roots. The presented experimental methods show the possibility of determining influences of modified cutting edge shapes and to adapt the drill to the needs of the high performance drilling.

MODELING OF THE DYNAMIC PROCESS RELEASE OF STUCK DRILLING TOOLS BY HYDRO-PULSE METHOD

2019 ◽  
pp. 94-103
Author(s):  
K. H. Levchyk ◽  
M. V. Shcherbyna
Keyword(s):  
Mathematical Model ◽  
Dynamic Process ◽  
Drilling Fluid ◽  
Pulse Method ◽  
Geometrical Parameters ◽  
Technical Solution ◽  
Rock Layer ◽  
Drilling Tool ◽  
Drilling Tools ◽  
Drill Pipes

A technical solution is proposed for the elimination the grabbing of drilling tool, based on the use of energy due to the circulation of the drilling fluid. The expediency eliminating the grabbing drilling tool using the hydro-impulse method is substantiated. A method of drawing up a mathematical model for the dynamic process of a grabbing string of drill pipes in the case of perturbation of hydro-impulse oscillations in the area of the productive rock layer is developed. The law of longitudinal displacements arising in the trapped string is obtained, which allows choosing the optimal geometrical parameters of the passage channels and the frequency rotational of shutter for these channels. Recommendations for using this method for practical use have been systematized.

scholarly journals Kinematics and dynamics analysis of new rotary-percussive PDM drilling tool

2021 ◽  
pp. 146134842198915
Author(s):  
Jialin Tian ◽  
Xuehua Hu ◽  
Liming Dai ◽  
Lin Yang ◽  
Yi Yang ◽  
...  
Keyword(s):  
Drill String ◽  
Structure Design ◽  
Drilling Process ◽  
Analysis Model ◽  
Drilling Tool ◽  
Stick Slip ◽  
Rate Of Penetration ◽  
Bottom Hole ◽  
Bottom Hole Assembly ◽  
The Impact

This paper presents a new drilling tool with multidirectional and controllable vibrations for enhancing the drilling rate of penetration and reducing the wellbore friction in complex well structure. Based on the structure design, the working mechanism is analyzed in downhole conditions. Then, combined with the impact theory and the drilling process, the theoretical models including the various impact forces are established. Also, to study the downhole performance, the bottom hole assembly dynamics characteristics in new condition are discussed. Moreover, to study the influence of key parameters on the impact force, the parabolic effect of the tool and the rebound of the drill string were considered, and the kinematics and mechanical properties of the new tool under working conditions were calculated. For the importance of the roller as a vibration generator, the displacement trajectory of the roller under different rotating speed and weight on bit was compared and analyzed. The reliable and accuracy of the theoretical model were verified by comparing the calculation results and experimental test results. The results show that the new design can produce a continuous and stable periodic impact. By adjusting the design parameter matching to the working condition, the bottom hole assembly with the new tool can improve the rate of penetration and reduce the wellbore friction or drilling stick-slip with benign vibration. The analysis model can also be used for a similar method or design just by changing the relative parameters. The research and results can provide references for enhancing drilling efficiency and safe production.

scholarly journals Effects of preferential flow on snowmelt partitioning and groundwater recharge in frozen soils

2019 ◽  
Vol 23 (12) ◽  
pp. 5017-5031 ◽  
Author(s):  
Aaron A. Mohammed ◽  
Igor Pavlovskii ◽  
Edwin E. Cey ◽  
Masaki Hayashi
Keyword(s):  
Soil Moisture ◽  
Groundwater Recharge ◽  
Preferential Flow ◽  
Frozen Soil ◽  
Time Lags ◽  
Runoff Generation ◽  
Frozen Ground ◽  
Soil Matrix ◽  
Frozen Soils ◽  
Flow Through

Abstract. Snowmelt is a major source of groundwater recharge in cold regions. Throughout many landscapes snowmelt occurs when the ground is still frozen; thus frozen soil processes play an important role in snowmelt routing, and, by extension, the timing and magnitude of recharge. This study investigated the vadose zone dynamics governing snowmelt infiltration and groundwater recharge at three grassland sites in the Canadian Prairies over the winter and spring of 2017. The region is characterized by numerous topographic depressions where the ponding of snowmelt runoff results in focused infiltration and recharge. Water balance estimates showed infiltration was the dominant sink (35 %–85 %) of snowmelt under uplands (i.e. areas outside of depressions), even when the ground was frozen, with soil moisture responses indicating flow through the frozen layer. The refreezing of infiltrated meltwater during winter melt events enhanced runoff generation in subsequent melt events. At one site, time lags of up to 3 d between snow cover depletion on uplands and ponding in depressions demonstrated the role of a shallow subsurface transmission pathway or interflow through frozen soil in routing snowmelt from uplands to depressions. At all sites, depression-focused infiltration and recharge began before complete ground thaw and a significant portion (45 %–100 %) occurred while the ground was partially frozen. Relatively rapid infiltration rates and non-sequential soil moisture and groundwater responses, observed prior to ground thaw, indicated preferential flow through frozen soils. The preferential flow dynamics are attributed to macropore networks within the grassland soils, which allow infiltrated meltwater to bypass portions of the frozen soil matrix and facilitate both the lateral transport of meltwater between topographic positions and groundwater recharge through frozen ground. Both of these flow paths may facilitate preferential mass transport to groundwater.

Geothermal modeling of soil or mine tailings with concurrent freezing and deposition

1998 ◽  
Vol 35 (2) ◽  
pp. 234-250 ◽  
Author(s):  
JF (Derick) Nixon ◽  
Nick Holl
Keyword(s):  
Snow Cover ◽  
Mine Tailings ◽  
Frozen Soil ◽  
Freezing And Thawing ◽  
Frozen Ground ◽  
Geothermal Model ◽  
Winter Time ◽  
Upper Boundary ◽  
Good Agreement

A geothermal model is described that simulates simultaneous deposition, freezing, and thawing of mine tailings or sequentially placed layers of embankment soil. When layers of soil or mine tailings are placed during winter subfreezing conditions, frozen layers are formed in the soil profile that may persist with time. The following summer, warmer soil placement may not be sufficient to thaw out layers from the preceding winter. Remnant frozen soil layers may persist for many years or decades. The analysis is unique, as it involves a moving upper boundary and different surface snow cover functions applied in winter time. The model is calibrated based on two uranium mines in northern Saskatchewan. The Rabbit Lake scenario involves tailings growth to a height of 120 m over a period of 24 years. At Key Lake, tailings increase in height at a rate of 1.3 m/year. Good agreement between the observed position of frozen layers and those predicted by the model is obtained. Long-term predictions indicate that from 80 to 200 years would be required to thaw out the frozen layers formed during placement, assuming 1992 placement conditions continue. Deposition rates of 1.5-3 m/year give the largest amounts of frozen ground. The amount of frozen ground is sensitive to the assumed snow cover function during winter.Key words: geothermal, model, tailings, freezing, deposition.

Impact of seasonally frozen soil on germinability and antioxidant enzyme activity of Picea asperata seeds

2009 ◽  
Vol 39 (4) ◽  
pp. 723-730 ◽  
Author(s):  
Jihong Qin ◽  
Qing Liu
Keyword(s):  
Oxidative Stress ◽  
Antioxidant Defense ◽  
Germination Rate ◽  
Antioxidant Defense System ◽  
Antioxidant Enzyme Activity ◽  
Frozen Soil ◽  
Defense System ◽  
Frozen Ground ◽  
Subalpine Zone ◽  
Picea Asperata

In the subalpine zone of the Qinghai–Tibetan Plateau of China, Dragon spruce (Picea asperata Mast.) is commonly used for reforestation. The aim of the present work was to study the effects of seasonally frozen soil on the germination of P. asperata seeds and to investigate whether these effects were associated with resumption of the antioxidant defense system. The nonfrozen treatment resulted in near failure of germination (1%) and was associated with relatively high levels of hydrogen peroxide (H2O2) and low activities of superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxide (APX). Germination of P. asperata seeds at 10 cm under the seasonally frozen soil was higher than that at 5 cm by 26%; this higher germination rate was associated with the recovery of SOD, CAT, and APX activities. The levels of malondialdehyde (MDA) in seeds from seasonally frozen treatments were higher than those in the nonfrozen treatment, implying greater lipid peroxidation and that frozen seeds might have suffered from oxidative stress. The results indicate that seasonally frozen soil facilitated the germination of P. asperata seeds and that germination was closely related to the resumption of antioxidant enzymes activity. Overall, these findings suggest that the disappearance of seasonally frozen ground caused by global warming might result in failure of regeneration of P. asperata.

Small Holes Fabrication on Soda Glass by Self-Elastic Polycrystalline Diamond Tool

2012 ◽  
Vol 516 ◽  
pp. 516-521
Author(s):  
Chung Chieh Cheng ◽  
Dong Yea Sheu
Keyword(s):  
Surface Roughness ◽  
Diamond Tool ◽  
Polycrystalline Diamond ◽  
The Self ◽  
High Quality ◽  
Drilling Tool ◽  
Drilling Tools ◽  
Absorbing Materials ◽  
New Type ◽  
Small Holes

This study describes a novel process to drill small holes in brittle materials such as glass, silicon and ceramic using a self-elastic polycrystalline diamond (PCD) drilling tool. In order to improve the surface roughness and reduce crack of the small holes, a new type of self-elastic PCD drilling tool equipped with vibration absorbing materials inside the housing was developed to fabricate small holes in glass in this study. The self-elastic PCD drilling tools could absorb the mechanical force by the vibration absorbing materials while the PCD tool penetrates into the small holes. Compared to conventional PCD drilling tools, the experimental results show that high-quality small holes drilled in glass can be achieved with cracking as small as 0.02mm on the outlet surface using the self-elastic PCD drilling tool.

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