Experimental analysis of user forces by test bench and manual hammer drill experiments with regard to vibrations and productivity

The use of a percussion hammer can provide high penetration rates through hard rocks when air drilling. The work of this paper was partly sponsored by the US Department of Energy to develop hammer drilling techniques for drilling deep hard rocks, using real drilling muds. Unfortunately, development is complicated because understanding rock breakage and cuttings removal under the dynamic loading conditions of hammer drilling is difficult. Historically, empirical relations have been used to relate hammer blow energy and blow rate with drilling. This paper presents results of carefully measured single cutter impact—as well as high rate and ‘static’—rock indentation tests under high borehole pressure conditions, using real drilling muds. The results include cutter force-displacement and crater volumes for both first stress wave (initial impact) and long time (quasi static) rock indentations. From this, specific energy for rock breakage (i.e. the energy to excavate a unit volume of rock) can be calculated. The specific energy values measured in these single cutter impact tests show the rock destruction efficiency that can be achieved by impact loading. They are compared with specific energies measured during full scale hammer and rotary drilling experiments, under relatively similar conditions. For a given rock type, impact stress, cutter configuration, wellbore pressure, and mud type are shown to be critical parameters. A key observation is that most of the rock breakage occurs during the first stress-wave, and for higher impact stresses above the dynamic confined indentation strength, relatively little additional rock breakage seems to occur.

Higher rate of penetration (ROP) indicates successful drilling operation but is not the only drilling success measure. However, Conventional ROP prediction methods focus on increasing ROP and neglect the hole cleaning state, which can be altered by ROP changes. Higher ROP in vertical and deviated wells may increase cutting concentration, leading to hole cleaning problems such as overpulling and stuck pipe. With this problem in mind, this paper utilized geological, rheological, and drilling data of 31 vertical wells across four oil fields located in the Egyptian Western Desert, developed intelligent ROP prediction model through back propagation neural network (BPNN), and compared the proposed BPNN results with an empirical model. Finally, the pattern recognition algorithms including discriminant analysis, support vector machines, and neural network pattern recognition (NNPR) were implemented to discriminate hole cleaning efficiency following the ROP prediction process. Recognition models were developed based on predicted ROP, bit wear rate, specific energy, and drilling fluid carrying capacity index to evaluate hole cleaning. The accuracy of the multi-strategy classifier was evaluated using area under curve, confusion matrix, and receiver operating characteristic. The BPNN model outperformed the empirical model in terms of linear correlation coefficient (R = 98.6%) and average absolute error (AAE = 5.5%). Additionally, the best classification performance was achieved using the NNPR algorithm with 91% accuracy and a cross-validation error equal to zero. For validity, the proposed approach predicted ROP and classified hole cleaning efficiency for new vertical well in adjacent oil field, resulting in a 6% improvement in ROP.

The penetration rates of dispersed and non-dispersed water-base muds were studied using Mancos Shale. The full-scale wellbore simulator at Drilling Research Laboratory was utilized. Previous studies1 have indicated that in invert oil muds higher penetration rates can be achieved when the weighting agent is ilmenite rather than barite. This study compares barite and ilmenite in water-base systems. Two grind sizes of ilmenite (fine and standard) were used in order to determine the effects of particle size on penetration rate. In addition to these tests, hematite, fine-grind ilmenite and barite were tested in a low colloid invert oil mud system as a supplement to the original study. An additional test was conducted with a conventional diamond bit and the low colloid oil mud for comparison. Highest penetration rates were observed with the standard particle size distribution ilmenite for the water-base muds. For the invert oil mud, similar penetration rates were observed for the fine-grind ilmenite and the hematite; the barite weighted mud resulted in relatively lower rates of penetration. The fine grind ilmenite/low colloid oil mud/diamond bit combination provided penetration rates equal to or greater than the barite/low colloid oil mud/roller cone bit combination.

A comparative study has been made of the penetration into leaf disks of Phaseolus vulgaris of (a) phenoxyacetic acid and its 2-, 4-, 2,4-, 2,6-, 3-5, 2,4,5-, and 2,4,6chloro derivatives, and (b) benzoic acid and its 2-, 2,4-, 2,5-, 2,3,6 chloro and 3,6-dichloro-2-methoxy derivatives. The methods of synthesis of each compound with 14C incorporated in the carboxyl group are described. In the series of substituted phenoxyacetic acids it was established that only for 2,4,5-T was there an appreciable loss of radioactivity from the system either in the light or darkness. In contrast, with the exception of 2,4-DCBA, 14C is lost from each member of the series of substituted benzoic acids. The level and pattern of penetration in the two series is differentially affected by chlorination. In general progressive chlorination of phenoxyacetic acid leads to an increase in the rate of penetration in both light and darkness. There are, however, exceptions; for illuminated disks the rate of entry of 2,4,5-T is exceeded by 2,4,6-T, 2,4-D, and 2,6-D whereas in the dark 2,4,5-T has by far the highest rate of penetration. Progressive chlorination of benzoic acid, however, depresses entry in both light and darkness. Possible relationships between these findings and changes in selected physical properties of each series of compounds have been examined. Between members of the series of substituted phenoxyacetic acids there is little variation in the dis sociation constant whereas for the substituted benzoic acids there is a marked lowering of the pK as the degree of chlorination increases. The rate of elution with chloroform of each compound from a buffered Silocel column gives a measure of the degree of partition into a lipid medium at a given pH. At pH 5-2 chlorination of phenoxyacetic acid results in more rapid elution whereas chlorina tion of benzoic acid causes a longer hold up. An apparatus was designed to enable measurements to be made of the rate at which a compound moves from one aqueous phase to another through a layer of lipid. Chlorination promotes the rate of transfer of phenoxyacetic acid through octanol but retards the transfer of benzoic acid. The extent to which chlorination depresses the rate of transfer of benzoic acid matches the diminution in the rate of leaf penetration. For the series of substituted phenoxyacetic acids transfer rates and penetration rates follow similar trends in the dark but in the light agree ment is less good. These findings are discussed in relation to prior studies on the rate of uptake and the metabolic fate of the individual compounds in a number of plant tissues. Journal of Experimental Botany, Vol. 20, No. 63, pp. 426-50, May 1969. This content downloaded from 207.46.13.163 on Fri, 08 Jul 2016 06:06:55 UTC All use subject to http://about.jstor.org/terms Studies on Foliar Penetration, III 427

Hierarchical estimation of uncertainties in multi-rotors:A yaw-motion study using test bench

<div class="section abstract"><div class="htmlview paragraph">In the quest for reduced cost and shorter development times for fuel cell systems in industrial applications, two major issues arise. First, the electrochemical behavior of fuel cell systems is inherently difficult to predict. Second, testing fuel cell systems is resource intensive. These issues compound: Setting up an accurate model of a fuel cell system incurs long testing periods for model validation. Further, it does not guarantee acceptable results outside the tested range or for other membrane electrode assembly compositions.</div><div class="htmlview paragraph">To mitigate these two major issues an X in the Loop concept is proposed. Essentially, this is the direct integration of the test sample, here a single fuel cell, into the modelling environment of the whole system. In practice, two strategies with different levels of integration are defined.</div><div class="htmlview paragraph">The first strategy consists of initially deducing the operating parameters of the sample cell from the fuel cell system model. Then, setting them to the sample cell in the test bench. The response of the test sample is finally used to validate the designed system or update the parameters of the fuel cell model.</div><div class="htmlview paragraph">The second strategy is a step further towards the integration of the test sample into the model. Here, the core model of the fuel cell inside the fuel cell system model is completely replaced with the test sample, reducing the need for an accurate electrochemical model while improving the prediction of the behavior of the fuel cell system.</div><div class="htmlview paragraph">Compared to previously proposed testing concepts, here the balance of plants is directly integrated through a digital emulator, leading to a closer representation of the complete system. Furthermore, the test bench results are looped back to the model at run-time leading to a closer match between testing conditions and the real world as well a reduced impact of inaccuracies in the modelling of the fuel cell.</div><div class="htmlview paragraph">On the way to realizing this goal, an experimental test bench capable of showcasing working prototypes of the proposed operating strategies has been built.</div></div>

This paper presents a strategy to emulate a reduced scale of sucker rod pump using laboratory test bench. The strategy is based on combination of software and hardware system. Torque reference is generated using the proposed strategy based on real time model of sucker rod pump that runs in LabVIEW. The output of encoder and torque sensor are integrated through NI PCI- 6221 data acquisition card to the real time platform. The performance of the experimental test bench is evaluated using current, voltage, speed, and torque measurements and power calculations. The experimental results are compared to simulation results. The results indicate the capability of this test bench to serve as a platform for conducting experimental studies on sucker rod pump.

Biological pollution creates significant obstacles in the operation of power plants' technical water supply cooling systems (SCS). To minimize biological pollution, methods of corrective treatment with biocides are implemented. While these biocides effectively prevent fouling of the cooling system, they can also adversely affect the environment and structural materials. By evaluating structural materials' corrosion resistance and biocides' environmental safety for the cooling water during biocide treatment, any potential issues can be identified and addressed before they become a safety or operational concern. The paper presents the results of bench tests of the corrosion resistance of structural materials SCS, corrosion aggressiveness of the biocides: sodium hypochlorite NaClO and 2, 2-dibromo-3-nitriloropionamide (DBNPA), and the results of measurements of the concentration of biocides and their decomposition products to assess compliance with environmental standards when discharging return water when applying from biocides treatment. The cooling water SCS of the Rivne NPP (Nuclear Power Plant) was chosen as the research object. Bench corrosion tests were carried out using samples of corrosion indicators from materials: steels Ст20, 08Х18Н10Т; copper alloy МНЖ-5-1 and aluminum, which are defined as analogs of structural materials of the technical water supply system of the Rivne NPP. The conditions of operation of the technical water SCS of the Rivne NPP were simulated on the test bench, and corrosion rate measurement was carried out by the gravimetric method.

Drilling performance is becoming the top differentiator in the market, especially in highly competitive US land basins. This drives operators to input more energy into the system with higher rev/min, flow, and weight on bit (WOB). In many cases this energy is transformed into drilling dysfunction (shock and vibration [S&V]) instead of higher rate of penetration (ROP). To minimize drilling dysfunction and maximize energy efficiency, a fully digital and closed-loop workflow was developed. The workflow begins with use of a proprietary at-bit sensor, which captures high-resolution at-bit measurements of three-axis acceleration, torsional vibration, and rev/min. The tool is placed inside any existing bit and does not require an additional sub, thus not introducing extra connections, bottomhole assembly (BHA) integrity risk, and/or length. The high-resolution data is automatically processed and analyzed to reveal critical drilling dynamics, which are replicated in a digital model. This creates a highly accurate virtual environment in which to evaluate bit design, eliminating the cost and risk of real-world trial and error, enabling efficient, fit-for-purpose introduction of new technologies. The new digital workflow was first used in a challenging, interbedded application in East Texas. High frequency at-bit measurements were used to develop a new bit and data-driven operating parameter roadmaps. These yielded improved drilling performance, with 69% higher ROP, better dull conditions, and 67% lower vibrations locally, when compared to the direct operator offsets. The workflow was then used in a curve/lateral application in the Permian Basin, known for challenging S&V conditions. Key performance targets were single-run to total depth (TD), high dogleg severity (DLS) output in the curve, and record ROP in the lateral. A new bit was designed, and recommended drilling parameters were defined within the data-driven virtual environment. Field testing confirmed the model’s predictions, with a 10% average increase in ROP. High-resolution at-bit downhole measurements coupled with digital simulation capabilities have led to development of a new workflow driving the evolution of drill bit design. Instead of the traditional trial and error approach that costs resources, time, and performance, the new workflow with data-enhanced digital modelling and virtual drilling environment enables increased confidence, optimized solutions, and decreased cycle time.

Drilling activity in Brazil has been focused primarily on developing offshore oil reserves in the high-profile pre/post salt plays. However, test wells in the Sao Francisco basin in the central state of Minas Gerais, have identified a vast opportunity for onshore natural gas production from unconventional tight sandstone and carbonate formations. The prospect is attractive because of its relatively shallow depth that varies from 2000 to 4000 meters and its close proximity to high population density. These gas rich formations present an important mixture of medium to hard lithologies that are at the same time highly dipped and faulted. This represents a great challenge for the drilling engineers and service companies while trying to maintain the verticality of the well and drilling at a competitive rate of penetration (ROP). During the last two years drilling activities in the basin have intensified as the need for an abundant source of energy becomes more evident. This necessity is directly proportional to Brazil's economical surge in the last decade. The invigorated economy is consuming more goods and energy and the existing traditional ways of powering the economy might no longer be sufficient. The answer appears to be natural gas, already proven to be abundant in the area but held captive in super tight formations. When oil companies were approached, they set for their main objective to drill vertical wells into the gas producing formations in the most efficient manner as possible. In Brazil's land drilling activities, economics are crucial due to the characteristics of the oil and gas companies and the high number of wells needed to produce at commercial levels. Since then, the operating companies have experimented with several drilling technologies attempting to extract the hydrocarbons at an economic level. Field trials include impregnated bits on turbines, hybrid bits, fluid/electromagnetic hammers and high speed motors (PDM) and rotary steerable tools (RSS). All BHAs met the goal with limited success and two major issues, lack of ROP and hole deviation problems. To solve the daunting challenges, the service company recommended drilling with nitrogen/air and hammer bits to increase ROP and maintain hole verticality to reduce/eliminate expensive correction runs. This way more wells could be drilled cheaper and much faster. As a result of this under balanced drilling approach, two wells were successfully drilled with percussion hammers which enabled the operator to maintain verticality from top to bottom with less than 5° deviation and at a much higher rate of penetration. This increased performance, in addition to the better control of verticality allowed for a reduction of total drilling time and translated to reduction in total well cost. The time to drill the two wells with air took approximately 30 days (wells to 1500-2000m), whereas in the other group of wells in the basin with conventional methods, the average time was no less than 50 days, depending on the area of the basin and targeted TD.

The main annulus hot gas ingress into turbine wheel-spaces is still one of the most challenging problem designers face. During the decades, several experimental test benches were developed worldwide to improve the knowledge associated to the rim seal flow physics. Even if in some cases quite complex and advanced rig configurations were proposed, limitations in the operating conditions and in the reproduction of the real engine geometries/characteristics into the rig are present. In this paper, validated CFD computations are used to explore the impact of some experimental rigs design choices/limitations on the sealing effectiveness prediction and their ability to mimic the real engine configuration behaviour. Attention is paid on several test rig related aspects such as operating conditions, flow path configuration (blade and vane count) and accuracy in the real engine rim seal geometry reconstruction applied to the rig. From the computations it emerges that a scaled geometry operated at lab conditions is able to mimic pretty well the real engine sealing performance when rig and engine experience the same flow path ΔCp. The ability of the rig to match the engine data is not affected by the differences in main annulus Mach number between test bench and engine. A further result that emerges from the computation regards the fact that the Φ0 - ΔCp0.5 curve is not linear, proving that the linear extrapolation of rim sealing performance from test bench to real engine when rig and engine are characterized by different ΔCp0.5 values is not of general application and an alternative approach is given. Finally, it is found that the impact of vane count on the rim sealing effectiveness is significant, making the extrapolation of data from rig to engine difficult.

Subject of study. Technology for quantum key distribution in fiber-optic communication lines under the influence of electromagnetic fields generated by atmospheric discharges is studied. Aim of study. A test bench for testing experimental techniques to be used in studying the effect of atmospheric discharges on transmission of a quantum key via fiber-optic communication lines is developed. Method. The characteristics of a quantum communication channel upon exposure of a coil containing an optical fiber to a magnetic field from a pulsed current are experimentally studied. Main results. An experimental test bench has been created and methods have been developed to evaluate the influence of magnetic fields arising from atmospheric discharges (lightning) on the transmission speed of a quantum key in fiber-optic communication lines. It was shown that quantum key distribution blocks using the BB84 phase-encoding protocol continue to show operational stability when the optical cable is exposed to alternating magnetic fields of up to 1.2 mT. However, the very fact of exposure to magnetic fields above 0.8 mT can be detected by a systematic decrease in the quantum key transmission rate and an increase in the quantum bit error rate (QBER) by 0.5%–1%. Practical significance. The laboratory test bench and methods developed herein support magnetic-field testing of various optical cables used for transmission of qubits. Fiber-optic networks through which qubits are transmitted can serve as a distributed lightning sensor; an increase in the level of quantum errors and a decrease in quantum key generation rate will be observed in any segment of an optical network where a lightning discharge generates strong magnetic fields.

A tyre-rim interaction digital twin for biaxial loading conditions

The auther has stunied on the penetration rates at Tsuchizaki-oki Oil Field and Kumoide Gas Field, especially on the effect of the bit weight and the rotary speed. Resnlts obtained are as follows: 1. At shallower formations the penetration rate per revolution is affected by the bit weight linearly (Figs. 2 and 7).2. At medium depth the penetration rate per revolution is affected both by the bit weight and the rotary speed. Higher penetration rate per ravolution is obtained at lower rotary speed. At higher rotary speed than a certain limit, the penatration rate dots not incrase with the rncrease of ratary speed (Fig. 8).3. At deeper formetions the penetration rate is affected only by the bit weight and not by the rotary speed (Figs. 3, 5 and 9).

With the development of intelligent transportation system (ITS) and vehicle to X (V2X), the connected vehicle is capable of sensing a great deal of useful traffic information, such as queue length at intersections. Aiming to solve the problem of existing models’ complexity and information redundancy, this paper proposes a queue length sensing model based on V2X technology, which consists of two sub-models based on shockwave sensing and back propagation (BP) neural network sensing. First, the model obtains state information of the connected vehicles and analyzes the formation process of the queue, and then it calculates the velocity of the shockwave to predict the queue length of the subsequent unconnected vehicles. Then, the neural network is trained with historical connected vehicle data, and a sub-model based on the BP neural network is established to predict the real-time queue length. Finally, the final queue length at the intersection is determined by combining the sub-models by variable weight. Simulation results show that the sensing accuracy of the combined model is proportional to the penetration rate of connected vehicles, and sensing of queue length can be achieved even in low penetration rate environments. In mixed traffic environments of connected vehicles and unconnected vehicles, the queuing length sensing model proposed in this paper has higher performance than the probability distribution (PD) model when the penetration rate is low, and it has an almost equivalent performance with higher penetration rate while the penetration rate is not needed. The proposed sensing model is more applicable for mixed traffic scenarios with much looser conditions.