Study of drilling muds on the anti-erosion property of a fluidic amplifier in directional drilling

2015 ◽  
Author(s):  
Jiang-fu He ◽  
Peng-yu Zhang ◽  
Qi-lei Yin ◽  
Kun Yin ◽  
Hou-ping Liu
Keyword(s):  
Particle Size ◽  
Service Life ◽  
High Speed ◽  
Great Influence ◽  
Life Time ◽  
Solid Content ◽  
Drilling Process ◽  
Jet Velocity ◽  
Drilling Muds ◽  
Erosion Property

Due to some drawbacks of conventional drilling methods and drilling tools, the application of hydraulic hammers with a fluidic amplifier have been extensively popularized since its emergence in recent years. However, the performance life of a fluidic amplifier is still unsatisfactory in oil and gas wells drilling, especially the heavy wear or erosion of the fluidic amplifier leads to the reduction of service life time of hydraulic hammers, which is derived from the incision of drilling muds with high speed and pressure. In order to investigate the influence of drilling muds, such as particle size, solid content and jet velocity, on the antierosion property of a fluidic amplifier, several groups of drilling muds with different performance parameters have been utilized to numerical simulation on basis of Computational Fluid Dynamics (CFD). Simulation results have shown that the jet nozzle of fluidic amplifiers is primarily abraded, afterwards are the lateral plates and the wedge of the fluidic amplifier, which shows extraordinary agreement with the actual cases of fluidic amplifier in drilling process. It can be concluded that particle size, solid content and jet velocity have a great influence on the anti-erosion property of a fluidic amplifier, and the erosion rate linearly varies with the particle size of drilling muds, nevertheless exponentially varies with solid content and jet velocity of drilling muds. As to improve the service life time of a fluidic amplifier, the mud purification system or low solid clay-free mud system is suggested in the operation of directional well drilling.

Experimental Research on Microburrs of High Speed Drilling of PCB Using Microdrill

2012 ◽  
Vol 497 ◽  
pp. 215-219 ◽  
Author(s):  
Xiao Hu Zheng ◽  
Zhi Qiang Liu ◽  
Cheng Yong Wang ◽  
Qing Long An ◽  
Ming Chen
Keyword(s):  
High Speed ◽  
Copper Foil ◽  
Great Influence ◽  
Burr Formation ◽  
Drilling Process ◽  
Fiber Plastic ◽  
High Speed Drilling ◽  
Micro Hole ◽  
Three Stages ◽  
Exit Burr

Microburrs have great influence on printed circuit board’s quality. PCB is composed of glass fiber plastic reinforcement material and copper foil. The PCB microburrs are generated in copper foil drilling process. These burrs are generated by copper extrusion and accumulation around the micro-hole. Enter burr and exit burr is quite different. Enter burrs are lower than exit burrs. The burr formation experienced three stages: First, Copper foil extrudes with the feed of microdrill; Second, Most of the Materials are cut off by drill tip and the rest of material; At last, rollover burrs appear when drill enters or exits uncut chip rolls.

Effects of CCL inorganic filler on hole performance in PCB drilling process

Circuit World ◽  
2018 ◽  
Vol 44 (4) ◽  
pp. 161-164
Author(s):  
Cuiming Du ◽  
Yanxia Xing ◽  
Liangpeng Hao ◽  
Peng Hu ◽  
Songgang Chai
Keyword(s):  
Particle Size ◽  
Printed Circuit Boards ◽  
Filler Content ◽  
Filler Particle ◽  
Great Influence ◽  
Inorganic Filler ◽  
Drilling Process ◽  
Drilling Tool ◽  
Content Type ◽  
Drilling Performance

Purpose This paper aims to investigate and document the effects of copper-clad laminate (CCL) inorganic filler on the hole performance in printed circuit boards drilling process. Design/methodology/approach Drilling of brittle laminates can result in hole cracking, layer-to-layer delamination and drill-bit wear and tool breakage. Adding large amount of fillers not only shortens the life of the drilling tool but also affects the drilling properties significantly regarding hole quality. This paper introduces the influence of filler content, type, hardness, particle size and the compounding method in the manufacture of the CCL on the drilling performance. Findings The filler content, filler type, hardness of filler, particle size of filler and the compounding method used for the filler have a great influence on the drilling properties of CCL. The higher the filler content, the larger the particle size and the more the hardness of the filler, the worse the drilling properties. The combination of hard particles like silica with softer particles can improve the drilling performance of CCL. Originality/value The paper describes what affects the drilling performance of CCL and how this knowledge can be used to design CCL with good drilling performance.

Influence of the choice of wear criterion on the life of high speed machine manual taps

2020 ◽  
pp. 74-78
Author(s):  
A.E. Dreval
Keyword(s):  
Service Life ◽  
Structural Steel ◽  
Tool Life ◽  
High Speed ◽  
High Speed Steel ◽  
Parameter Dependence ◽  
Limiting State ◽  
Thread Cutting ◽  
Failure Life ◽  
High Speed Machine

The assessment of the limiting state of high-speed machine-manual taps in the processing of structural steel billets is considered. A general multi-parameter dependence is developed for calculating the criterion of allowable wear, which makes it possible to rationally use the tool life and normalize the cut amount during regrinding. Keywords thread cutting, tap, angle of the cutting part, criterion, high-speed steel, wear, failure, life, service life. [email protected]

Optimization of Solid Lipid Nanoparticles of Ezetimibe in Combination with Simvastatin Using Quality by Design (QbD)

2020 ◽  
Vol 10 (4) ◽  
pp. 404-418
Author(s):  
Kruti Borderwala ◽  
Ganesh Swain ◽  
Namrata Mange ◽  
Jaimini Gandhi ◽  
Manisha Lalan ◽  
...  
Keyword(s):  
Particle Size ◽  
Solid Lipid Nanoparticles ◽  
High Speed ◽  
Entrapment Efficiency ◽  
Lipid Nanoparticles ◽  
Water Soluble ◽  
Lipid Matrix ◽  
Solid Lipid ◽  
32 Factorial Design ◽  
Full Factorial Experimental Design

Background: The objective of this study was to develop solid lipid nanoparticles (SLNs) of poorly water soluble anti-hyperlipidemic drugs-Ezetimibe in combination with Simvastatin. Methods: This study describes a 32 full factorial experimental design to optimize the formulation of drug loaded lipid nanoparticles (SLN) by the high speed homogenization technique. The independent variables amount of lipid (GMS) and amount of surfactant (Poloxamer 188) were studied at three levels and arranged in a 32 factorial design to study the influence on the response variables- particle size, % entrapment efficiency (%EE) and cumulative drug release (% CDR) at 24 h. Results: The particle size, % EE and % CDR at 24 h for the 9 batches (B1 to B9) showed a wide variation of 104.6-496.6 nm, 47.80-82.05% (Simvastatin); 48.60-84.23% (Ezetimibe) and 54.64-92.27% (Simvastatin); 43.8-97.1% (Ezetimibe), respectively. The responses of the design were analysed using Design Expert 10.0.2. (Stat-Ease, Inc, USA), and the analytical tools of software were used to draw response surface plots. From the statistical analysis of data, polynomial equations were generated. Optimized formulation showed particle size of 169.5 nm, % EE of 75.43% (Simvastatin); 79.10% (Ezetimibe) and 74.13% (Simvastatin); 77.11% (Ezetimibe) %CDR after 24 h. Thermal analysis of prepared solid lipid nanoparticles gave indication of solubilisation of drugs within lipid matrix. Conclusion: Fourier Transformation Infrared Spectroscopy (FTIR) showed the absence of new bands for loaded solid lipid nanoparticles indicating no interaction between drugs and lipid matrix and being only dissolved in it. Electron microscope of transmission techniques indicated sphere form of prepared solid lipid nanoparticles with smooth surface with size approximately around 100 nm.

Design of Electrolytic Strengthening Machine for Cutting Edge of Cutter

2016 ◽  
Vol 693 ◽  
pp. 1585-1590
Author(s):  
Yi Zhuo Guo ◽  
Xian Guo Yan ◽  
Shu Juan Li ◽  
Hong Guo
Keyword(s):  
Service Life ◽  
Calculation Method ◽  
High Speed ◽  
High Speed Steel ◽  
Cutting Edge ◽  
The Cost ◽  
Electric Quantity

Many studies have proved the service life of cutter can be prolonged by electrolytic strengthening. Based on the theory of electrolytic strengthening technology, this paper introduced and developed prototype equipment for strengthening cutting edge of rotary cutter and put forward a calculation method of total electric quantity consumption during the electrolysis suitable for microcontroller. The M8 high-speed steel tap is taken as a strengthening example. After finished the strengthening process that it clearly see the results of the surface of tap was obviously polished by observing the micrograph. This equipment improves the reliability of electrolytic strengthening and the cost is relatively cheap.

scholarly journals Splatters and Aerosols Contamination in Dental Aerosol Generating Procedures

2021 ◽  
Vol 11 (4) ◽  
pp. 1914
Author(s):  
Pingping Han ◽  
Honghui Li ◽  
Laurence J. Walsh ◽  
Sašo Ivanovski
Keyword(s):  
Particle Size ◽  
Disease Transmission ◽  
High Speed ◽  
Low Speed ◽  
Dental Procedures ◽  
Dental Equipment ◽  
Produce Contamination ◽  
Fluorescein Dye ◽  
Filter Papers ◽  
Airborne Disease

Dental aerosol-generating procedures produce a large amount of splatters and aerosols that create a major concern for airborne disease transmission, such as COVID-19. This study established a method to visualise splatter and aerosol contamination by common dental instrumentation, namely ultrasonic scaling, air-water spray, high-speed and low-speed handpieces. Mock dental procedures were performed on a mannequin model, containing teeth in a typodont and a phantom head, using irrigation water containing fluorescein dye as a tracer. Filter papers were placed in 10 different locations to collect splatters and aerosols, at distances ranging from 20 to 120 cm from the source. All four types of dental equipment produced contamination from splatters and aerosols. At 120 cm away from the source, the high-speed handpiece generated the greatest amount and size (656 ± 551 μm) of splatter particles, while the triplex syringe generated the largest amount of aerosols (particle size: 1.73 ± 2.23 μm). Of note, the low-speed handpiece produced the least amount and size (260 ± 142 μm) of splatter particles and the least amount of aerosols (particle size: 4.47 ± 5.92 μm) at 120 cm. All four dental AGPs produce contamination from droplets and aerosols, with different patterns of distribution. This simple model provides a method to test various preventive strategies to reduce risks from splatter and aerosols.

scholarly journals Particle Size Effect of Lanthanum-Modified Bismuth Titanate Ceramics on Ferroelectric Effect for Energy Harvesting

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Sangmo Kim ◽  
Thi My Huyen Nguyen ◽  
Rui He ◽  
Chung Wung Bark
Keyword(s):  
Particle Size ◽  
Energy Harvesting ◽  
High Speed ◽  
High Performance ◽  
Bismuth Titanate ◽  
Vinylidene Fluoride ◽  
Piezoelectric Materials ◽  
Renewable Energy Sources ◽  
Particle Size Effect ◽  
Ferroelectric Materials

AbstractPiezoelectric nanogenerators (PNGs) have been studied as renewable energy sources. PNGs consisting of organic piezoelectric materials such as poly(vinylidene fluoride) (PVDF) containing oxide complex powder have attracted much attention for their stretchable and high-performance energy conversion. In this study, we prepared a PNG combined with PVDF and lanthanum-modified bismuth titanate (Bi4−XLaXTi3O12, BLT) ceramics as representative ferroelectric materials. The inserted BLT powder was treated by high-speed ball milling and its particle size reduced to the nanoscale. We also investigated the effect of particle size on the energy-harvesting performance of PNG without polling. As a result, nano-sized powder has a much larger surface area than micro-sized powder and is uniformly distributed inside the PNG. Moreover, nano-sized powder-mixed PNG generated higher power energy (> 4 times) than the PNG inserted micro-sized powder.

Penetration Dynamics of Solid Particles into Liquids High-Speed Experimental Results and Modelling

2005 ◽  
Vol 473-474 ◽  
pp. 429-434 ◽  
Author(s):  
Olga Verezub ◽  
György Kaptay ◽  
Tomiharu Matsushita ◽  
Kusuhiro Mukai
Keyword(s):  
Contact Angle ◽  
Particle Size ◽  
Aqueous Solutions ◽  
Particle Velocity ◽  
Weber Number ◽  
High Speed ◽  
Solid Particles ◽  
Bulk Liquid ◽  
Distilled Water ◽  
Critical Weber Number

Penetration of model solid particles (polymer, teflon, nylon, alumina) into transparent model liquids (distilled water and aqueous solutions of KI) were recorded by a high speed (500 frames per second) camera, while the particles were dropped from different heights vertically on the still surface of the liquids. In all cases a cavity has been found to form behind the solid particle, penetrating into the liquid. For each particle/liquid combination the critical dropping height has been measured, above which the particle was able to penetrate into the bulk liquid. Based on this, the critical impact particle velocity, and also the critical Weber number of penetration have been established. The critical Weber number of penetration was modelled as a function of the contact angle, particle size and the ratio of the density of solid particles to the density of the liquid.

Dynamic characteristics of a drill in the drilling process

2003 ◽  
Vol 217 (2) ◽  
pp. 161-167 ◽  
Author(s):  
B W Huang
Keyword(s):  
Dynamic Characteristics ◽  
High Speed ◽  
Thrust Force ◽  
Time Dependent ◽  
Drilling Process ◽  
Improve Quality ◽  
Vibration Model ◽  
High Speed Drilling ◽  
Spinning Speed ◽  
Twisted Beam

The dynamic characteristics of high-speed drilling were investigated in this study. To improve quality and produce a higher production rate, the dynamic characteristics of the drilling process need to be studied. A pre-twisted beam is used to simulate the drill. The moving Winkler-type elastic foundation is used to approximate the drilling process. A time-dependent vibration model for drilling is presented. The spinning speed, pre-twisted angle and thrust force effects of the drill are considered. The numerical analysis indicates that the natural frequency is suddenly reduced as the drill moves into a workpiece.

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