scholarly journals Research on the Dynamics of Geological Drilling Rig against Drill Pipe Impact

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Shixin Bai ◽  
Zhijian Liu ◽  
Jin Wang
Keyword(s):  
Drill Pipe ◽  
Academic Research ◽  
Subsequent Development ◽  
Hydraulic Motor ◽  
Relief Valve ◽  
Working Pressure ◽  
Drilling Rig ◽  
Geological Surveys ◽  
Drilling Rigs ◽  
The Impact

With the ever-increasing demand for resources, the task of geological surveys has increased rapidly, and automated geological drilling rigs that can improve the efficiency of geological surveys have become the mainstream research direction. Automated geological drilling rigs can improve construction efficiency, reduce labor intensity, and effectively reduce construction accidents. During the construction of geological survey operations, accidents such as drill breakage, stuck drill, and equipment damage, which are easily caused by drill pipe impact, occur from time to time. Therefore, drill pipe impact dynamics is currently a hot topic in academic research, but there are few studies that combine automated geological drilling rigs with drill pipe impact. This article starts with the research on the hydraulic system of the power head of the automatic drilling rig and studies the dynamics of the damage of the power head of the drilling rig caused by the impact of the drill pipe by means of hydraulic valve torque limit and closed-loop control of the speed. The oil valve group reduces the reverse torsional impact of the drill pipe on the hydraulic motor. At the same time, the requirements for the selection and pressure setting of the relief valve in the buffer filling oil valve group are proposed. The natural frequency of the relief valve is not less than 20 Hz, and the pressure is set to the working pressure 1.25 times. The effects of shock with or without the buffer filling oil valve group and the oil supply line on the power head motor were compared. The research results of this paper can provide theoretical reference and design basis for subsequent development of automated drilling rigs.

THE INFLUENCE OF FRICTION FORCES ON LONGITUDINAL WAVE PROPAGATION IN A STUCK DRILL STRING IN A BOREHOLE

Tribologia ◽  
2018 ◽  
Vol 282 (6) ◽  
pp. 79-87
Author(s):  
Yevhen KHARCHENKO ◽  
Andrii HUTYI ◽  
Volodymyr HAIDUK
Keyword(s):  
Oil And Gas ◽  
Drill Pipe ◽  
Computer Software ◽  
Drill String ◽  
The Body ◽  
Friction Forces ◽  
Impact Mechanism ◽  
Drilling Rig ◽  
Longitudinal Wave Propagation ◽  
The Impact

A mathematical model and the computer software for the analysis of dynamic processes occurring in the drilling pipes in the borehole under stuck drill string release by means of an impact mechanism (a jerking device) or a pulse-wave installation, equipped with electric linear pulse motor are presented. The drill string with an impact mechanism, which is inserted over the stuck section after failure, is detected and is activated by lowering and taking the non-stuck upper part of the string by means of the drilling rig drive and is considered as a discrete-continuous mechanical system. As a result of the impact of the hammer on the body of the impact mechanism, wave processes are formed in the drill string, which helps to release the stuck drill string. The influence of friction forces on propagation of longitudinal waves in the drill pipe string is investigated. Practical recommendations are developed regarding the above-mentioned efficiency of drilling for oil and gas.

Effect of Steering Gear Parameters of Crawler Tractor Cornering Ability

2016 ◽  
Vol 20 (2) ◽  
pp. 159-169
Author(s):  
Cheslav Zhdanovich ◽  
Michail Mamonov ◽  
Maciej Kuboń ◽  
Jan Radosław Kamiński
Keyword(s):  
Maximum Pressure ◽  
Hydraulic Motor ◽  
Hydraulic Pump ◽  
Working Pressure ◽  
Oil Pump ◽  
Power Regulation ◽  
Drive Speed ◽  
Dry Soil ◽  
Turning Radius ◽  
The Impact

AbstractCrawler tractor with specific loads on the hitch loses traction abilities during cornering and causes intensive destruction of the surface layer of soil. This phenomenon may be limited if relevantly selected parameters of the cornering mechanisms were applied. The objective of the paper was to determine the impact of the cornering mechanism parameters on the crawler tractor maneuver ability. The object of the research was a planetary cornering mechanism which enables fluent change of the cornering radius through the change of the rotational speed of planetary gears drive by pneumatic engines. Relations of the turning radius to the slip of the spinning and overleaping crawler at the speed of 7 km·h-1 without the load on the hitch and with the load of 40 kN were defined. The average values of drift and the turning radius as a function of drive speed from 0 to 2.5 m·s−1 on the moist soil μ=0.4 and dry soil μ=0.8 were determined. Relations of the turning radius to the pressure of oil pump oil, to the drive speed and to the load on the hitch were set forth. The research proved that when using the hydraulic pump with the regulated expense the working pressure of oil may be maximally reduced to 30 MPa, the power of the pump may be reduced by twofold, the possibility of turning in difficult field conditions within the scope of the required speed may be enabled. To ensure the required turning radius of the crawler tractor it is recommended to install the pump with the efficiency of 33 cm3·rot−1 and a regulated hydraulic motor with the capacity of 56 сm3·rot−1 with a power regulation within 2.0-2.5, at the same time maximum pressure of liquid will not exceed 35 MPa and the determined power of the hydraulic gear will amount to 52.6 kW.

scholarly journals The Impact of CSR on the Capital Structure of High-Tech Companies in Poland

2021 ◽  
Vol 13 (10) ◽  
pp. 5467
Author(s):  
Barbara Grabinska ◽  
Dorota Kedzior ◽  
Marcin Kedzior ◽  
Konrad Grabinski
Keyword(s):  
Capital Structure ◽  
Financial Reporting ◽  
Academic Research ◽  
Debt Financing ◽  
High Tech ◽  
High Tech Industry ◽  
Reporting Practices ◽  
Csr Reporting ◽  
The Impact ◽  
The Capital Structure

So far, CSR’s role in the high-tech industry is not fully explained by academic research, especially concerning the most burdensome obstacle to firms’ growth: acquiring debt financing. The paper aims to solve this puzzle and investigate whether young high-tech companies can attract more debt by engaging in CSR activity. To address the high-tech industry specificity, we divided CSR-reporting practice into three broad categories: employee, social, and environmental and analyzed their impact on the capital structure. Our sample consists of 92 firm-year observations covering the period 2014–2018. Using a regression method, we found out that only employee CSR plays a statistically significant role in shaping capital structure. We did not find evidence for the influence of the other types of CSR-reporting practices. The results suggest that employees are the key resource of high-tech companies, and, for this reason, they are at the management’s focus. This fact is visible at the financial reporting level and, as we interpret results, is also considered by credit providers. In a more general way, our results suggest that firms tend to choose CSR based on the importance of crucial resources.

scholarly journals Absence of Association between Previous Mycoplasma pneumoniae Infection and Subsequent Myasthenia Gravis: A Nationwide Population-Based Matched Cohort Study

2021 ◽  
Vol 18 (14) ◽  
pp. 7677
Author(s):  
Kuan Chen ◽  
James Cheng-Chung Wei ◽  
Hei-Tung Yip ◽  
Mei-Chia Chou ◽  
Renin Chang
Keyword(s):  
Cohort Study ◽  
Myasthenia Gravis ◽  
Mycoplasma Pneumoniae ◽  
Pathogenic Bacteria ◽  
Case Reports ◽  
Statistical Significance ◽  
Subsequent Development ◽  
Population Based ◽  
Cox Proportional Hazards ◽  
The Impact

Mycoplasma pneumoniae (M. pneumoniae) is not only one of the most common pathogenic bacteria for respiratory infection but also a trigger for many autoimmune diseases. Its infection process shared many similarities with the pathogenesis of myasthenia gravis (MG) at cellular and cytokine levels. Recent case reports demonstrated patients present with MG after M. pneumoniae infection. However, no epidemiological studies ever looked into the association between the two. Our study aimed to investigate the relationship between M. pneumoniae infection and subsequent development of MG. In this population-based retrospective cohort study, the risk of MG was analyzed in patients who were newly diagnosed with M. pneumoniae infection between 2000 and 2013. A total of 2428 M. pneumoniae patients were included and matched with the non-M. pneumoniae control cohort at a 1:4 ratio by age, sex, and index date. Cox proportional hazards regression analysis was applied to analyze the risk of MG development after adjusting for sex, age, and comorbidities, with hazard ratios and 95% confidence intervals. The incidence rates of MG in the non-M. pneumoniae and M. pneumoniae cohorts were 0.96 and 1.97 per 10,000 person-years, respectively. Another case–control study of patients with MG (n = 515) was conducted to analyze the impact of M. pneumoniae on MG occurrence as a sensitivity analysis. The analysis yielded consistent absence of a link between M. pneumoniae and MG. Although previous studies have reported that M. pneumoniae infection and MG may share associated immunologic pathways, we found no statistical significance between M. pneumoniae infection and subsequent development of MG in this study.

scholarly journals Sustainability of Food Placement in Retailing during the COVID-19 Pandemic

2021 ◽  
Vol 13 (11) ◽  
pp. 5956
Author(s):  
Jelena Končar ◽  
Radenko Marić ◽  
Goran Vukmirović ◽  
Sonja Vučenović
Keyword(s):  
Supply Chain ◽  
Academic Research ◽  
Food Prices ◽  
Future Research ◽  
Retail Sector ◽  
Western Balkans ◽  
Skilled Workers ◽  
Empirical Survey ◽  
Definition Of ◽  
The Impact

This work aims to define the impact of different indicators on the sustainability of food placement in the retail sector, during periods of crisis and emergencies, such as the COVID-19 pandemic. An empirical survey conducted in the Western Balkans (WB) region showed that indicators such as developed infrastructure, consistency, and transparency of the supply chain, skilled workers, costs, food safety, food prices, energy consumption, and changes in consumer needs are statistically significant since they affect the sustainability of food placement in the retail sector. As food placement and the retail sector itself are inseparable from other participants in the food supply chain (FSC), an analysis was conducted at the level of all FSC sectors. The results showed some deviations viewed individually in the sectors of production, physical distribution, wholesale, and retail, and in selected Western Balkan countries. Based on the results obtained, the sustainability model of food placement in the retail sector has been defined. The model will serve as the basis for defining the set of measures and incentives that competent institutions and FSC management need to undertake, to minimize the impact of indicators that endanger sustainability. The originality of the study lies in the fact that it fills the research gap that exists in this subject matter in academic research and studies in the WB region. In addition, some indicators important for food placement have been precisely isolated, with the definition of the intensity of their impact, observed overall at the level of the entire FSC as well as by individual sectors. Guidelines and suggestions for future research are listed in the paper.

scholarly journals ‘I’m not being paid for this conversation’: Uncovering the challenges of artist–academic collaborations in the neoliberal institution

2019 ◽  
Vol 23 (3) ◽  
pp. 317-333
Author(s):  
Alena Pfoser ◽  
Sara de Jong
Keyword(s):  
Collaborative Work ◽  
Knowledge Exchange ◽  
Academic Research ◽  
The Political ◽  
Institutional Pressures ◽  
Negative Effects ◽  
Collective Response ◽  
And Shifts ◽  
The Impact

Artist–academic collaborations are fuelled by increasing institutional pressures to show the impact of academic research. This article departs from the celebratory accounts of collaborative work and pragmatic toolkits for successful partnerships, which are dominant in existing scholarship, arguing for the need to critically interrogate the structural conditions under which collaborations take place. Based on a reflexive case study of a project developed in the context of Tate Exchange, one of the UK’s highest-profile platforms for knowledge exchange, we reveal three sets of (unequal) pressures, which mark artist–academic collaborations in the contemporary neoliberal academy: asymmetric funding and remuneration structures; uneven pressures of audit cultures; acceleration and temporal asymmetries. Innovations at the level of individual projects or partners can only mitigate the negative effects to a limited extent. Instead this article offers a systemic critique of the political economy of artist–academic collaborations and shifts the research agenda to developing a collective response.

Design and simulation analysis of impact-resistant flexible drill pipe for rock-breaking rig

2021 ◽  
pp. 095745652110307
Author(s):  
Kangping Gao ◽  
Xinxin Xu ◽  
Ning Shi ◽  
Shengjie Jiao
Keyword(s):  
Impact Force ◽  
Drill Pipe ◽  
Rock Breaking ◽  
Control Model ◽  
Simulation Software ◽  
System Stability ◽  
Series Elastic Actuator ◽  
Pipe Model ◽  
The Impact ◽  
Series Elastic

In the process of drilling and coring by the rock-breaking rig, the drill rod is affected by the intermittent impact force, which reduces the efficiency of the rig to break the rock and increases the cost of the drilling and coring. Therefore, it is very important to improve the impact resistance of the drill pipe during the rock-breaking process. To achieve this goal, a flexible design of the drill pipe was carried out, and a dynamical model of the drilling rig based on a series elastic actuator was established. Considering the dynamic performance of the system, a torque feedforward link is introduced and a control model based on the force source is established. The influence of the equivalent inertia of the transmission system and the series elastic actuator damping coefficient on the system stability was analyzed by drawing the frequency domain characteristic curve of the system. By using the control and Simulink simulation software, the electromechanical simulation of the model is carried out, and the torque step tracking response of the system is obtained. A torque feedforward link is introduced to establish the control model of the system based on force source. Through dynamic simulation software ADAMS, dynamic and static impact simulation experiments were carried out on the system. The results show that when a force of 200 N is applied to the output end of the drill pipe in the tangential direction, the maximum moments received by the joint under static and dynamic environments are 34.1 N·m and 57.9 N·m, respectively. When the impact force disappears, the time required for the flexible drill pipe to reach a stable state is only 0.15 s, which verifies that the series elastic actuator–based drill pipe model can alleviate the impact of the external environment and protect the internal structure of the rig.

Re-using Open Government Data (OGD) published by the Election Commission of India (ECI)

foresight ◽  
2018 ◽  
Vol 20 (5) ◽  
pp. 507-526 ◽  
Author(s):  
Stuti Saxena
Keyword(s):  
Academic Research ◽  
Vote Share ◽  
Open Government ◽  
Party Affiliation ◽  
Content Type ◽  
Demographic Profiles ◽  
Open Government Data ◽  
Government Data ◽  
The Impact ◽  
Election Commission

Purpose The paper aims to “re-use” the Open Government Data (OGD) published by the Election Commission of India (ECI). Bihar’s performance across General Elections, 2014, and Bihar Legislative Assembly Elections, 2015, is compared, wherein the role of contestants’ demographic profiles in determining their vote share is being investigated. Design/methodology/approach Hypotheses are derived based on the impact of contestants’ demographic profiles (age, marital status, social category, political party affiliation, educational qualification, availing telephone and email facility, criminal antecedents) on their vote share. Following a quantitative approach, multiple regression and logistic regression are used to draw inferences from the data contestants’ affidavits – sourced from the ECI website. Findings Results show that contestants’ demographic profiles impact their vote share in the elections. While the ECI website is a viable source for re-using the data available there, data are not available in a user-friendly format and this leads to difficulty in being re-used by different stakeholders. Originality/value Academic research on OGD re-use is negligible, and the present study seeks to contribute towards extant literature by underlining the significance of re-using OGD by drawing inferences from the data accessible via ECI.

scholarly journals Psychology and interviewing: what direction now in our quest for reliable information?

2011 ◽  
Vol 13 (2) ◽  
pp. 135-144 ◽  
Author(s):  
Gavin E. Oxburgh ◽  
Coral J. Dando
Keyword(s):  
Empirical Research ◽  
Academic Research ◽  
Psychological Theory ◽  
Investigative Interviewing ◽  
Future Directions ◽  
Content Type ◽  
The Impact ◽  
Emergent Theory ◽  
And Training ◽  
Do So

PurposeThe purpose of this paper is to discuss two distinct but interrelated areas, namely witness/victim and suspect interviewing, and to argue that both must continue to evolve, suggest how they might do so, and that this process must be driven by emergent theory and contemporary empirical research.Design/methodology/approachThe paper outlines the impact of psychological theory and empirical research to investigative interviewing in recent decades.FindingsIt is argued that in order to stay ahead of the game, the field of investigative interviewing (suspect and witness) must continue to evolve in such a manner that not only protects and fosters the important practitioner/academic relationship, but also ensures that future directions are driven by empirical research, with recourse to emergent theory.Originality/valueThe paper outlines the impact of psychological theory and empirical research on investigative interviewing and the consequent enhancement of the interviewing of both suspected offenders and witnesses. The paper demonstrates that working closely together academic research can make a difference, and influence law, policy decisions and training guidelines in order to improve practice.

Numerical Simulations of Ocean Drilling System Behavior With a Surface or a Subsea BOP in Waves and Current

2008 ◽  
Author(s):  
Celso K. Morooka ◽  
Raphael I. Tsukada ◽  
Dustin M. Brandt
Keyword(s):  
System Behavior ◽  
Traditional System ◽  
Drilling Rig ◽  
Advantages And Disadvantages ◽  
Ocean Drilling ◽  
Sea Bottom ◽  
Drilling System ◽  
Drilling Rigs ◽  
High Level ◽  
Drilling Bit

Subsea equipment such as the drilling riser and the subsea Blow-Out Preventer (BOP) are mandatory in traditional systems used in deep sea drilling for ocean floor research and petroleum wellbore construction. The drilling riser is the vertical steel pipe that transfers and guides the drill column and attached drilling bit into a wellbore at the sea bottom. The BOP is used to protect the wellbore against uncontrolled well pressures during the offshore drilling operation. Presently, there is a high level of drilling activity worldwide and in particular in deeper and ultra-deeper waters. This shift in depth necessitates not only faster drilling systems but drilling rigs upgraded with a capacity to drill in the deep water. In this scenario, two general drilling systems are today considered as alternatives: the traditional system with the subsea BOP and the alternate system with the surface BOP. In the present paper, the two systems are initially described in detail, and a numerical simulation in time domain to estimate the system behavior is presented. Simulations of a floating drilling rig coupled with the subsea and surface BOP in waves and current are carried out for a comparison between the two methods. Results are shown for riser and BOP displacements. Critical riser issues for the systems are discussed, comparing results from both drilling system calculations. Conclusions are addressed showing advantages and disadvantages of each drilling system, and indicating how to correct the problems detected on each system.

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