scholarly journals Effects of Nozzle Exit Angle on the Pressure Characteristics of SRWJs Used for Deep-Hole Drilling

2019 ◽  
Vol 9 (1) ◽  
pp. 155 ◽  
Author(s):  
Deng Li ◽  
Zu’an Wang ◽  
Miao Yuan ◽  
Qi Fan ◽  
Xiaochuan Wang
Keyword(s):  
Standoff Distance ◽  
Hole Drilling ◽  
Exit Angle ◽  
Deep Hole ◽  
Axial Pressure ◽  
Pressure Oscillations ◽  
Experimental Conditions ◽  
Deep Hole Drilling ◽  
Practical Applications ◽  
Working Efficiency

The self-resonating waterjet (SRWJ) has been applied in petroleum, natural gas, and mining engineering ever since its strong erosion ability in deep-hole drilling was recognized. Aiming at further improving the working efficiency of SRWJs, the effects of the exit angle of the organ-pipe nozzle on the axial pressure oscillations of the jet were experimentally studied. Six exit angles of θ = 0°, 30°, 45°, 60°, 75°, and 90° were employed in the experiment, and the axial pressure oscillation peak (Pmax) and amplitude (Pa) were used for characterizing the performance of SRWJs. It was found that the exit angle greatly affects the axial pressure oscillations, including the development trends against the standoff distance and the magnitudes of Pmax and Pa. Under testing with two inlet pressures, the exit angle of θ = 0° always resulted in the greatest Pmax and Pa within the range of the testing standoff distance. With the increase of standoff distance, both Pmax and Pa first increased and then decreased when the exit angle was 0°; while they kept decreasing when the exit angle was 30°, 45°, 60°, 75°, and 90°. Moreover, the exit angles of θ = 90° and 60°, corresponding to inlet pressures of Pi = 10 MPa and 20 MPa, led to both the minimum magnitudes of Pmax and Pa under the experimental conditions. The results also indicate that the exit angle affects the interactions between the nozzle lip and the jet and help provide information for improving the working efficiency of SRWJs in practical applications.

scholarly journals The Effects of the Downstream Contraction Ratio of Organ-Pipe Nozzle on the Pressure Oscillations of Self-Resonating Waterjets

Energies ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 3137 ◽  
Author(s):  
Xiaoliang Wang ◽  
Yong Kang ◽  
Mengda Zhang ◽  
Miao Yuan ◽  
Deng Li
Keyword(s):  
Pressure Oscillation ◽  
Inlet Pressure ◽  
Hole Drilling ◽  
Relative Pressure ◽  
Deep Hole ◽  
Axial Pressure ◽  
Pressure Oscillations ◽  
Deep Hole Drilling ◽  
Contraction Ratio ◽  
Organ Pipe

Self-resonating waterjets (SRWJs) are being widely used in the fields of energy exploitation, due to the significantly increased penetration rate of roller bits in deep-hole drilling. To further improve the impact and erosion abilities of SRWJs, the effects of the downstream contraction ratio of organ-pipe nozzle on the axial pressure oscillations were experimentally studied. The axial pressure oscillation peak and amplitude were used to evaluate the effects under two inlet pressures and various standoff distances. The results show that the downstream contraction ratio can affect the development trends of the pressure oscillations and determines the values of the peaks and amplitudes. Under the experimental conditions, 2.5 is the ratio that leads to the maximum peaks and amplitudes at almost all the testing standoff distances, while the ratio of 2 always results in the minimum ones. The development trend of the pressure oscillation peak for the ratio of 3.5 has a great change at an inlet pressure of 20 MPa. Generally, the relative pressure oscillations are more violent at an inlet pressure of 10 MPa, which is regardless of the contraction ratio. This study helps provide a guideline for determining the physical parameters required in the fabrication of organ-pipe nozzles used for deep-hole drilling.

CAVIJET™ Augmented Deep-Hole Drilling Bits

1978 ◽  
Vol 100 (1) ◽  
pp. 52-59 ◽  
Author(s):  
A. F. Conn ◽  
R. P. Radtke
Keyword(s):  
Atmospheric Pressure ◽  
Test Chamber ◽  
Water Jet ◽  
Back Pressure ◽  
Standoff Distance ◽  
Hole Drilling ◽  
Deep Hole ◽  
Deep Hole Drilling

Drilling bits which exploit the destructive energy of cavitation are being developed. A systematic series of tests is now under way, first to establish feasibility, and then to define the effective adaptation of the CAVIJET™ cavitating water jet method for augmenting the cutting action of mechanical deep-hole drilling bits. Successful drilling tests, using a 1/4-in. (6.4-mm) CAVIJET nozzle, were performed at atmospheric pressure and in a test chamber which provided simulated wellbore pressures up to 3000 psi(21 MPa). The effect of back pressure on standoff distance, and a comparison of steady jet versus CAVIJET cutting efficiencies are discussed.

Deep Hole Drilling Technique (DHD)

2019 ◽  
Vol 88 (6) ◽  
pp. 485-488
Author(s):  
Shinji KAWAI ◽  
Takuya NAGAI ◽  
Shigetaka OKANO
Keyword(s):  
Hole Drilling ◽  
Deep Hole ◽  
Deep Hole Drilling ◽  
Drilling Technique

scholarly journals Temperature monitoring in the subsurface during single lip deep hole drilling

2020 ◽  
Vol 87 (12) ◽  
pp. 757-767
Author(s):  
Robert Wegert ◽  
Vinzenz Guski ◽  
Hans-Christian Möhring ◽  
Siegfried Schmauder
Keyword(s):  
Cutting Parameters ◽  
Drill Hole ◽  
Machining Process ◽  
Hole Drilling ◽  
Drilling Process ◽  
Deep Hole ◽  
Machining Processes ◽  
Deep Hole Drilling ◽  
Feed Force ◽  
Cutting Zone

AbstractThe surface quality and the subsurface properties such as hardness, residual stresses and grain size of a drill hole are dependent on the cutting parameters of the single lip deep hole drilling process and therefore on the thermomechanical as-is state in the cutting zone and in the contact zone between the guide pads and the drill hole surface. In this contribution, the main objectives are the in-process measurement of the thermal as-is state in the subsurface of a drilling hole by means of thermocouples as well as the feed force and drilling torque evaluation. FE simulation results to verify the investigations and to predict the thermomechanical conditions in the cutting zone are presented as well. The work is part of an interdisciplinary research project in the framework of the priority program “Surface Conditioning in Machining Processes” (SPP 2086) of the German Research Foundation (DFG).This contribution provides an overview of the effects of cutting parameters, cooling lubrication and including wear on the thermal conditions in the subsurface and mechanical loads during this machining process. At first, a test set up for the in-process temperature measurement will be presented with the execution as well as the analysis of the resulting temperature, feed force and drilling torque during drilling a 42CrMo4 steel. Furthermore, the results of process simulations and the validation of this applied FE approach with measured quantities are presented.

Optimization of roundness error in deep hole drilling using moth-flame optimization

2021 ◽  
Author(s):  
Anis Farhan Kamaruzaman ◽  
Azlan Mohd Zain ◽  
Noordin Mohd Yusof ◽  
Farhad Nadjarian ◽  
Rozita Abdul Jalil
Keyword(s):  
Hole Drilling ◽  
Deep Hole ◽  
Roundness Error ◽  
Deep Hole Drilling

scholarly journals Cutting-fluid flow with chip evacuation during deep-hole drilling with twist drills

2021 ◽  
Author(s):  
Andreas Baumann ◽  
Ekrem Oezkaya ◽  
Dirk Schnabel ◽  
Dirk Biermann ◽  
Peter Eberhard
Keyword(s):  
Fluid Flow ◽  
Cutting Fluid ◽  
Hole Drilling ◽  
Deep Hole ◽  
Deep Hole Drilling ◽  
Twist Drills

Hole Accuracy during Deep Hole Drilling for Hydraulic Cylinder Application

2014 ◽  
Vol 984-985 ◽  
pp. 67-72 ◽  
Author(s):  
R. Clifford Benjamin Raj ◽  
B. Anand Ronald ◽  
A. Velayudham ◽  
Prasmit Kumar Nayak
Keyword(s):  
Feed Rate ◽  
Drill Hole ◽  
Hydraulic Cylinder ◽  
High Accuracy ◽  
Diameter Ratio ◽  
Hole Drilling ◽  
Deep Hole ◽  
Deep Hole Drilling ◽  
Very High ◽  
Continuous Chip

Deep-hole drilling is a process in which the hole length will be very high when compared to diameter of the drill hole (i.e. length to diameter ratio will be greater than 5). Drilling a deep hole with very high accuracy is difficult process. The current project is about the production of deep hole with the aim to produce a chip which is not a continuous chip and also not a powdery chip. These conditions can be attained by varying the spindle speed and the tool feed rate.

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