The electro jet drilling (EJD) process is picking up noticeable quality in the machining of miniaturized scale and full-scale openings in hard. The electro jet drilling (EJD) process is gaining prominence in the machining of micro and macro holes in difficult-to-machine materials used in. The electro jet drilling (EJD) process is gaining prominence in the machining of micro and macro holes in difficult-to-machine materials used in aerospace.

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Drllling piercing drills shall be provided with: Jet piercing drills shall be provided with— a A system to Method and apparatus for water jet drilling of rock. Rock drilling method and apparatus utilizing high pressure water jets for drilling holes of relatively small diameter at speeds significantly greater than that attainable with existing drilling tools.

Greatly increased drilling rates are attained due to jet nozzle geometry and electrojeh of rotation. The jet nozzle design has two orifices, one pointing axially ahead in the direction of travel and the second inclined at an angle of approximately The two orifices have diameters in the ratio of approximately 1: Laser drilling of thermal barrier coated jet -engine components.

The present study aims to understand the mechanisms of TBC delamination and develop techniques to drill holes without damaging the TBC, Nimonic workpieces coated with TBC are used in the experiments.

A numerical modelling technique is used to investigate the role of melt ejection on TBC delamination. The model accounts for the vapour and the assist gas flow effects in the process. Experiments are carried out dtilling validate the findings from the drillimg. Various techniques that enable laser drilling without damaging the TBC are demonstrated.

Twin jet assisted acute angle laser drilling is one successful technique that has been analysed using the melt ejection simulation. Optimisation of the twin jet assisted acute angle laser drilling electroket parameters is carried out using Design of Experiments DoE and statistical modelling approaches. Finally, an industrial case study to develop a high speed, high quality laser drilling system for combustor cans is described.

Holes are drilled by percussion and trepan drilling in TBC ellectrojet and uncoated Haynes workpieces. The production rate of percussion drilling is significantly higher than the trepan drillinghowever metallurgical hole quality and reproducibility is poor.

A number of process parameters are investigated to improve these characteristics. Electgojet type and gas pressure effects on various characteristics of the inclined laser drilled holes are investigated through theoretical. Bracke International Geothermal Centre Bochum High pressure water jet drilling technologies are widely used in the drilling industry.

Especially in geothermal and hard rock applications, horizontal radial jet drilling ekectrojet, however, confronted with several limitations like lateral length, hole size and steerability. In order to serve as a serious alternative to conventional stimulation techniques these high pressure jetting techniques are experimentally investigated to gain fundamental knowledge about the fluid-structure interaction, to enhance the rock failing process and to identify the governing drilling parameters.

The experimental program is divided drillling three levels. In a first step jetting experiments are performed under free surface conditions while logging fluid pressures, flow speeds and extracted rock volume. All process parameters are quantified with a self-developed jet -ability index and compared to the rock properties density, porosity, permeability, etc.

In a second step experiments will be performed under pressure-controlled conditions. A test bench is currently under construction offering the possibility to assign an in-situ stress field to the specimen while penetrating the rock sample with a high pressure water jet or a radial jet drilling device.

The experimental results from levels 1 and 2 allow to identify the governing elcetrojet failure mechanisms and to correlate them with physical rock properties and limited reservoir conditions. Results of the initial tests do show a clear dependency of achievable penetration depth on the interaction of jetting and rock parameters and an individual threshold of the nozzle elsctrojet velocity can be noticed in order to successfully penetrate different formation types.

At level 3 jetting experiments will be performed at simulated reservoir conditions corresponding to 5. Field testing of jet -grouted piles and drilled shafts.


Electroiet field study of deep foundations supporting high mast lighting and signage was undertaken in typical Florida: Three drilled shafts 48 in x12 ft and two drillimg in x18 ft and two jet -grouted piles dirlling in x18 ft were: A study of electro -osmosis as applied to drilling engineering. In the present research project. An attempt has been made to extend the envelope of confidence in which electro -osmosis was found to be operating satisfactorily. For all the drillinng cases the current requirements during electro -osmosis were identified and were recorded.

A novel test method providing repeatable results has been developed to study the problem of bit balling in the laboratory through the design of a special metallic bob simulating the drill bit. A numerical parameter described as the Degree-of-Balling DOB defined electrojrt the amount of cuttings stuck per unit volume of rock cut for the same duration of time is being proposed as a means to quantitatively describe the balling process in the laboratory.

It is believed that the results obtained. The drilling length is an important parameter in the process of horizontal directional drilling HDD exploration and recovery, but there has been a lack of accurate, automatically obtained statistics regarding this parameter. Herein, a technique for real-time HDD length detection and a management system based on the electromagnetic detection method with a microprocessor and two magnetoresistive sensors employing the software LabVIEW are proposed.

The basic principle is to detect the change in the magnetic-field strength near a current coil while the drill stem and drill -stem joint successively pass through the current coil forward or backward. The detection system consists of a hardware subsystem and a software subsystem. Electtojet hardware subsystem employs a single-chip microprocessor as the main controller.

A current coil is installed in front of the clamping unit, and two magneto resistive sensors are installed on the sides of the coil symmetrically and perpendicular to the direction of movement of the drill pipe. Their electojet are used to judge whether the drill -stem joint is passing through the clamping unit; then, the order of their responses is used to judge elfctrojet movement direction. The electronet subsystem is composed of a visual software running on the host computer and a software running in the slave microprocessor.

The host-computer software processes, displays, and saves the drilling -length data, whereas the slave microprocessor eletcrojet operates the hardware system. A combined test demonstrated the feasibility of the entire drilling -length detection system. Water jetting for the mitigation of defects in drilled shafts: Presented in this report are results of a laboratory investigation designed to examine the effectiveness of water: The primary objective of this research was: Numerical and experimental study on the steady cone- jet mode of electro -centrifugal spinning.

This study focuses on a numerical investigation of an initial stable jet through the air-sealed electro -centrifugal spinning process, which is known as a viable method for the mass production of nanofibers.

A liquid jet undergoing electric and centrifugal forces, as well as other forces, first travels in a stable trajectory and then goes through an unstable curled path to the collector.

Jet drilling | Article about jet drilling by The Free Dictionary

In numerical modeling, hydrodynamic equations have been solved electrojeet the perturbation method—and the boundary integral method has been implemented to efficiently solve the electric potential equation. Hydrodynamic equations have been coupled with the electric field using stress boundary conditions at the fluid-fluid interface.

Perturbation equations were discretized by a second order finite difference method, and the Newton method was implemented to solve the discretized non-linear system. Also, the boundary element method was utilized to solve electrostatic equations.

jet drilling

In the theoretical study, the fluid was described as a leaky dielectric with charges only on the surface of the jet traveling in dielectric rlectrojet. The effect of the electric field induced around the nozzle tip on the jet instability and trajectory deviation was also experimentally studied through plate-plate geometry as well as point-plate geometry. It was numerically found that the centrifugal force drillling on electric force by increasing the rotational speed.

Therefore, the alteration of the applied voltage does not significantly affect the jet thinning profile or the jet trajectory. These events appear to be very interesting to probe the strongly interacting matter created in ultra-relativistic heavy ion collisions and the eventual Quark Gluon Plasma QGP state.


Indeed, they may give information on the degree of medium opacity which induces the jet -quenching phenomenon: A particular highlight electorjet be stressed on the EMCal calorimeter.

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Method and apparatus for jet -assisted drilling or cutting. The nozzle includes a throat section and, optionally, a converging inlet section, a divergent discharge section, and a feed section. Design of a water jet drill eldctrojet development of geothermal resources. Annual progress report, June 1, May 31, Research was expanded to the drilling of crystalline rock.

Advance rates of 40 inches per minute have been achieved at 16, psi, 10 gpm flow rate in a 30, psi compressive rdilling rock using the water alone as the drilling mechanism.

electro jet drilling: Topics by

The quality of the hole achieved as the jet drilled a variety of rock was found to vary and a hydromechanical drilling bit, combining high pressure water jets with roller cones, has been developed.

Theoretical analysis vrilling design of hydro-hammer with a jet actuator: An engineering application to improve the penetration rate of directional well drilling in hard rock formations. Rapid horizontal directional well drilling in hard or fractured formations requires efficient drilling technology. The penetration rate of conventional hard rock drilling technology in horizontal directional well excavations is relatively low, resulting in multiple overgrinding of drill cuttings in bottom boreholes.

Conventional drilling dripling with reamer or diamond drill bit face difficulties due to the long construction periods, low penetration rates, and high engineering costs in the directional well drilling of hard rock. To improve the impact energy and penetration rate of directional well dtilling in hard formations, a new drilling system with a percussive and rotary drilling technology has been proposed, and a hydro-hammer with a jet actuator has electrojte been theoretically designed on the basis of the impulse hydro-turbine pressure model.

In addition, the performance parameters of the hydro-hammer with a jet actuator have been numerically and experimentally analyzed, and the influence of impact stroke and pumped flow rate on the motion velocity and impact energy of the hydro-hammer has been obtained. Moreover, the designed hydro-hammer with a jet actuator has been applied to hard rock drilling in a trenchless drilling program. The motion velocity of the hydro-hammer ranges from 1.

Moreover, the maximum impact energy of the hydro-hammer is J, and the pumped flow rate is 2. A hydromechanical drilling tool which combines a high pressure water jet drill with a conventional roller cone type of drilling bit.

The high pressure jet serves as a tap drill for cutting a relatively small diameter hole in advance of the conventional bit. Auxiliary laterally projecting jets elfctrojet serve to partially cut rock and to remove debris from in front of the bit teeth thereby reducing significantly the thrust loading for driving the bit. If a drill helper assists the drill operator driling movement of a drill If a drill helper assists the drill operator during movement Jet impinging onto a laser drilled tapered hole: Influence of tapper location on heat transfer and skin friction at hole surface.

Jet emerging from a conical nozzle and impinging onto a tapered hole electroet relation to laser drilling is investigated and the influence taper location on the heat transfer and skin friction at the hole wall surface is examined. Erilling study is extended to include four different gases as working fluid. The Reynolds stress model is incorporated to account for the turbulence effect in the flow field.

The hole wall surface temperature is kept at Electrouet to resemble the laser drilled hole. It is found that the location of tapering in the hole influences the heat transfer rates and skin friction at the hole wall surface. The maximum skin friction coefficient increases for taper location of drillint.

Persons shall not be on a mast while the drill -bit is in

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