The Effect of Back Rake Angle on the Performance of Small-Diameter Polycrystalline Diamond Rock Bits: ANOVA Tests

1986 ◽  
Vol 108 (4) ◽  
pp. 305-309 ◽  
Author(s):  
C. L. Hough
Keyword(s):  
Specific Energy ◽  
Statistical Difference ◽  
Penetration Rate ◽  
Small Diameter ◽  
Polycrystalline Diamond ◽  
Rake Angle ◽  
Performance Criteria ◽  
Maximum Penetration ◽  
Rotary Speed ◽  
Selection Of

The effect of back rake angle on a center vacuum bit design was investigated through factorial Analysis of Variance (ANOVA) tests for drilling in shale. Multiple performance criteria: penetration rate, specific energy and torque were used in these tests. Thrust and rotary speed were the controlled variables. Results from ANOVA tests showed that rake angle has a significant effect on penetration rate and torque but not on specific energy. Further tests of means revealed that the 20-deg bit gave the maximum penetration rate although there was no statistical difference among the 15, 20 and 25-deg angles. Tests of means also revealed that the 7-deg bit gives the minimum torque, but is statistically the same as the 15 and 25-deg bits. The results of the test will be useful for design and selection of small-diameter bits for drilling in shale and sand formations.

Wear Characteristics of Polycrystalline Diamond Compact Drill Bits in Small Diameter Rock Drilling

1985 ◽  
Vol 107 (4) ◽  
pp. 534-542 ◽  
Author(s):  
C. L. Hough ◽  
B. Das
Keyword(s):  
Small Diameter ◽  
Polycrystalline Diamond ◽  
Wear Test ◽  
Test Results ◽  
Failure Characteristics ◽  
Wear Characteristics ◽  
Drill Bits ◽  
Rotary Speed ◽  
Polycrystalline Diamond Compact ◽  
Single Material

The wear characteristics of polycrystalline diamond compact (PDC) drill bits were investigated in the context of drilling small holes in a hard abrasive medium. An efficient method for measuring wear of the PDC drill bits was developed. The wear test results were grouped or categorized in terms of rotary speed, feed and wear or failure characteristics. Contrary to the three classical wear phases (break-in, uniform wear and rapid breakdown) of the single material cutters, four distinctive wear phases were formed for the PDC cutters: I–break-in, II–diamond wear, III–carbide wear, and IV–rapid breakdown. The characteristics of the wear phases were identified and some suggestions were made to alleviate the wear problem.

Life Models for Small-Diameter Polycrystalline Diamond Compact Bits in Hard Abrasive Media

1986 ◽  
Vol 108 (4) ◽  
pp. 310-314
Author(s):  
C. L. Hough ◽  
B. Das ◽  
T. G. Rozgonyi
Keyword(s):  
Cutting Speed ◽  
Small Diameter ◽  
Polycrystalline Diamond ◽  
Prediction Equation ◽  
Logarithmic Model ◽  
Drill Bits ◽  
Rate Versus ◽  
Rotary Speed ◽  
Bit Life ◽  
Polycrystalline Diamond Compact

Mathematical models for bit life of polycrystalline diamond compact (PDC) drill bits were developed for drilling small holes in hard abrasive media. Based on the wear-out criterion of an average 0.060 in. (1.5 mm) flank wear land, bit life equations were formulated in three forms: bit life versus rotary speed and feed rate, bit life versus rotary speed and penetration rate, and wear rate versus cutting speed and cutter engagement area. The traditional linear-logarithmic model proved inadequate to describe bit life, whereas the quadratic-logarithmic model provided the best bit life prediction equation. Consequently, it would be possible to predict the optimum economical drilling conditions more accurately by employing a quadratic-logarithmic based bit life equation. The equation demonstrated the ability to predict the bit life precisely under different modes of wear.

Relative Significance of Multiple Parameters on the Mechanical Specific Energy and Frictional Responses of Polycrystalline Diamond Compact Cutters

2016 ◽  
Vol 139 (2) ◽  
Author(s):  
Babak Akbari ◽  
Stefan Z. Miska
Keyword(s):  
Specific Energy ◽  
Polycrystalline Diamond ◽  
Friction Angle ◽  
Rake Angle ◽  
Fractional Factorial ◽  
Depth Of Cut ◽  
Relative Significance ◽  
Mechanical Specific Energy ◽  
Wellbore Pressure ◽  
Polycrystalline Diamond Compact

A high pressure single polycrystalline diamond compact (PDC) cutter testing facility was used to investigate the effect of five factors on PDC cutter performance on Alabama marble. The factors include: depth of cut (DOC), rotary speed, back rake angle, side rake angle, and confining (wellbore) pressure. The performance is quantified by two parameters: mechanical specific energy (MSE) and friction angle. Fractional factorial design of experiments methodology was used to design the experiments, enabling detection of potential interactions between factors. Results show that, in the range tested, the only statistically significant factor affecting the MSE is DOC. In other words, DOC's influence is predominant and it can mask the effect of all the other factors. These results could have applications in real time pore pressure detection. Further, the results show that back rake angle is the most statistically significant factor in friction angle. Side rake angle and depth of cut also affect the friction angle, but in a relatively unimportant manner. The MSE–DOC behavior is explained and modeled by cutter edge–groove friction and the circular cutter shape. It is speculated that high cutter edge friction overwhelms the actual cutting process. A comparison of five currently present models in the literature with these results is presented and the conclusion is that the future PDC cutter models should digress from the traditional shear failure plane models.

Development of New PDC Bits for Drilling of Geothermal Wells—Part 1: Laboratory Testing

1992 ◽  
Vol 114 (4) ◽  
pp. 323-331 ◽  
Author(s):  
H. Karasawa ◽  
S. Misawa
Keyword(s):  
Hard Rock ◽  
Rock Type ◽  
Penetration Rate ◽  
Polycrystalline Diamond ◽  
Rock Cutting ◽  
Rake Angle ◽  
Well Drilling ◽  
Pdc Bit ◽  
Geothermal Wells ◽  
Polycrystalline Diamond Compact

Rock cutting, drilling and durability tests were conducted in order to obtain data to design polycrystalline diamond compact (PDC) bits for geothermal well drilling. Both conventional and new PDC bits with different rake angles were tested. The rock cutting tests revealed that cutting forces were minimized at −10 deg rake angle independent of rock type. In drilling and durability tests, a bit with backrake and siderake angles of −10 or −15 deg showed better performance concerning the penetration rate and the cutter strength. The new PDC bit exhibited better performance as compared to the conventional one, especially in hard rock drilling. Furthermore, a new PDC core bit (98.4 mm o. d., 66 mm i. d.) with eight cutters could be successfully applied to granite drilling equally as well as a bit with twelve cutters.

scholarly journals A Fuzzy Network DEA Approach to the Selection of Advanced Manufacturing Technology

2021 ◽  
Vol 13 (8) ◽  
pp. 4236
Author(s):  
Tim Lu
Keyword(s):  
Fuzzy Numbers ◽  
Weighted Average ◽  
Careful Consideration ◽  
Performance Criteria ◽  
Advanced Manufacturing ◽  
Weight Restrictions ◽  
Network Dea ◽  
Engineering Sciences ◽  
Fuzzy Network ◽  
Selection Of

The selection of advanced manufacturing technologies (AMTs) is an essential yet complex decision that requires careful consideration of various performance criteria. In real-world applications, there are cases that observations are difficult to measure precisely, observations are represented as linguistic terms, or the data need to be estimated. Since the growth of engineering sciences has been the key reason for the increased utilization of AMTs, this paper develops a fuzzy network data envelopment analysis (DEA) to the selection of AMT alternatives considering multiple decision-makers (DMs) and weight restrictions when the input and output data are represented as fuzzy numbers. By viewing the multiple DMs as a network one, the data provided by each DM can then be taken into account in evaluating the overall performances of AMT alternatives. In the solution process, we obtain the overall and DMs efficiency scores of each AMT alternative at the same time, and a relationship in which the former is a weighted average of the latter is also derived. Since the final evaluation results of AMTs are fuzzy numbers, a ranking procedure is employed to determine the most preferred one. An example is used to illustrate the applicability of the proposed methodology.

scholarly journals Experimental Research on the Process Parameters of a Novel Low-Load Drill Bit Used for 7000 m Bedrock Sampling Base on Manned Submersible

2021 ◽  
Vol 9 (6) ◽  
pp. 682
Author(s):  
Yu-Gang Ren ◽  
Lei Yang ◽  
Yan-Jun Liu ◽  
Bao-Hua Liu ◽  
Kai-Ben Yu ◽  
...  
Keyword(s):  
Deep Sea ◽  
Field Tests ◽  
Polycrystalline Diamond ◽  
Design Criterion ◽  
Penetration Length ◽  
Technical Data ◽  
Low Load ◽  
Manned Submersible ◽  
Rotary Speed ◽  
Cutting Model

Due to the need for accurate exploration of deep-sea scientific research, drilling techniques by combining the operational advantages of the Jiaolong manned submersible is considered one of the most feasible methods for deep-sea bedrock drilling. Based on deep sea bedrock cutting model and discrete element simulation, as well as efficient drilling as the design criterion, the development of a deep sea 7000 m electromechanical coring apparatus was carried out. The outstanding feature of this technology is that the bit load produced by the drill pressure is usually within the range 100–400 N while the recommended load for diamond drilling is 1–3 KN or even more. Therefore, searching for the drilling bits that can drill in extremely hard formations with minimal load and acceptable rates of penetration and rotary speed is the necessary step to prove the feasibility of electromechanical deep-sea drilling technology. A test has been designed and constructed to examine three types of drill bits. The results of experiments show that the new low-load polycrystalline diamond compact (PDC) bit has the highest penetration length of 138 mm/15 min under a 300 N load and 250 rpm rotary speed. Finally, field tests with the Jiaolong submersible were used to conduct deep sea experiments and verify the load model, which provides theoretical and technical data on the use of a low-load core sampling drill developed specifically for a deep sea submersible.

scholarly journals Electric Discharge Grinding of Polycrystalline Diamond Materials

2012 ◽  
Vol 271-272 ◽  
pp. 333-337 ◽  
Author(s):  
Song Lin Ding ◽  
John P.T. Mo ◽  
Milan Brandt ◽  
Richard Webb
Keyword(s):  
Electrical Discharge ◽  
Material Removal ◽  
Working Condition ◽  
Removal Rate ◽  
Polycrystalline Diamond ◽  
Optimal Parameters ◽  
Power Generator ◽  
The Poor ◽  
Edm Process ◽  
Selection Of

The poor electric conductivity of polycrystalline diamond (PCD) makes it difficult to machine with the conventional EDM process. Inappropriate selection of parameters of the power generator and the servo system leads to unstable working condition and low material removal rate. This paper introduces a method to find optimal parameters in the Electrical Discharge Grinding (EDG) of PCD materials with Taguchi method. The theory and detailed procedures are presented, experimental results are analyzed. The optimized configuration was validated through confirmation tests.

scholarly journals CORROSION OF GALVANIZED STEEL AND ALUMINUM ALLOYS IN THE INDUSTRIAL ENVIRONMENT OF CHAMPIGNON

2019 ◽  
Vol 4 (5) ◽  
pp. 50-55
Author(s):  
С. Иконников ◽  
S. Ikonnikov ◽  
А. Блажнов ◽  
A. Blazhnov
Keyword(s):  
Aluminum Alloys ◽  
Penetration Rate ◽  
Galvanized Steel ◽  
Layer By Layer ◽  
Test Results ◽  
Structural Scheme ◽  
Construction Design ◽  
Alloys Of The Al ◽  
Rational Type ◽  
Selection Of

Generalization the experience building for the cultivation of champignons shows the diversity of construction solutions. The method of layer-by-layer assembly with galvanized steel and aluminum alloy coverings is economically feasible to use in champignons of frame structural scheme, enclosing structures of industrial premises. However, the technologically required wet air conditions of the premises and aggressive gases during construction design complicate the selection of a rational type of outer layers of enclosing structures. To reveal the rational material of coverings in the production premises of champignons, corrosion tests are carried out on samples of aluminum alloys of the Al-Mg, Al-Mn, Al-Mg-Si systems, technical aluminum, galvanized steel and galvanized steel with a protective coating. The type and corrosion penetration rate are set for the exposed samples. According to the test results, suitable covering materials for various types of champignon production premises are determined

Drill String Vibrations Due to Intermittent Contact of Bit Teeth

1963 ◽  
Vol 85 (2) ◽  
pp. 187-194 ◽  
Author(s):  
P. R. Paslay ◽  
D. B. Bogy
Keyword(s):  
Experimental Data ◽  
Penetration Rate ◽  
Drill String ◽  
String Vibrations ◽  
Order Of Magnitude ◽  
Intermittent Contact ◽  
Maximum Penetration ◽  
Sufficient Magnitude ◽  
Force Excitation ◽  
Practical Measurement

An analysis of the longitudinal forces and the resulting longitudinal motions of an idealized drill string is presented. The only external force excitation considered occurs at the bit and is due to the intermittent contact of the teeth with the bottom of the hole. Attention has been restricted to the following two salient possibilities: 1 - Excitation at the bit may develop oscillating forces at the bit with amplitudes of the same order of magnitude as those of the bit load. 2 - Appreciable bit load variation may be detected by instruments which measure the motion of the drill string near its top. The first possibility is important if maximum penetration rate is to be achieved, and the second possibility is important in implementing practical measurement of the phenomenon. From the results of the specific example considered in this report, it is concluded that possibilities 1 and 2 may occur in sufficient magnitude to be influential, but experimental data on the actual bit motion and the damping will be required to evaluate the effect. The analysis is presented in such form that the influence of the various parts of the system can easily be evaluated.

Power Control Schemes Based on Game Theory

2014 ◽  
pp. 244-276
Keyword(s):  
Game Theory ◽  
Power Control ◽  
Cellular Networks ◽  
Network Capacity ◽  
Performance Criteria ◽  
Transmitter Power ◽  
Geographic Coverage ◽  
Control Schemes ◽  
Link Data ◽  
Selection Of

Power control is the intelligent selection of transmitter power output in a communication system to achieve good performance within the system. The notion of good performance can depend on context and may include optimizing metrics such as link data rate, network capacity, geographic coverage and range, and life of the network and network devices. Power control algorithms are used in many contexts, including cellular networks, sensor networks, and wireless LANs. Typically, there is no simple answer to the problem of power control, and a good algorithm must strike a balance between the benefits and drawbacks associated with targeting a particular transmit power based on the performance criteria of most importance to the designer. This chapter discusses power control schemes.

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