Novel Open Circuit Displacement Control Architecture in Heavy Machinery

Author(s):  
Roman Ivantysyn ◽  
Jürgen Weber

Motivated by the ever-stricter demands by lawmakers to lower emissions of mobile machinery and increasing fuel prices, mobile machinery has gone through a paradigm shift. Fuel efficiency has become a major selling point of machine producers. Even the heavy machinery branch, which is mainly dominated by reliability, productivity and serviceability, has started to feel this change. Hydraulic systems of large scale, as can be found in mining excavators, have typically been based on simplicity and durability. Typical architectures are open-center hydraulic systems, which were designed with robustness and productivity in mind; however they lack competiveness with other hydraulic systems in terms of energy efficiency. Displacement control has shown promising potential especially in multi-actuator machines such as excavators. The technology has so far been demonstrated in closed circuit applications on small-scale machines (below 30 t). Large scale excavators however should in general be more suitable for displacement control due to their relatively small hydraulic component cost compared to the machine and operating cost, larger energy recovery potential due to larger mass movement, more flexibility in space management and greater hydraulic power installed. Large machines feature already several smaller pumps instead of a single large pump, which is important with respect to the fact that displacement control is based on one pump per actuator. A challenge for displacement control on large-scale machinery is handling their high volumetric flow-demands on the system. Today many large excavators feature a float valve, which short-circuits the cylinder chambers and ensures rapid lowering of the attachment under aiding load. Float valves ensure fast cycle times and are essential for high productivity, however incorporating this feature in displacement control is a challenge, especially in closed circuit systems. Open circuit displacement control systems have greater flexibility than closed circuit solutions in working with float-valves and dealing with the high volumetric flows. Additionally the open circuit architecture is ideal for pump-flow-sharing, the strategy to connect two or more pumps with one actuator, which can be practiced when not all actuators move at the same time. This paper compares displacement control in open circuit form with valve-controlled actuation in a mining excavator and shows several fuel saving potentials. The Open Center system was simulated and results were validated with measurements. The proposed open circuit displacement control solutions are implemented virtually and replace the valve-controlled system. Components and system-architecture were carefully chosen in order to ensure reliability, minimal component changes and redundancy that compare to the robustness of today’s system.

Author(s):  
Philipp C. Weishaar ◽  
Alexander Görres ◽  
Hubertus Murrenhoff ◽  
Katharina Schmitz

Common examples for electrostatic discharges can be encountered in everyday life. When approaching a grounded surface after walking on insulating flooring material or while riding an escalator one might experience an electrostatic discharge first hand. These discharges generally do not pose a problem but when translated to various fields of engineering, such as in hydraulics, discharges can be the root cause for system failures. The pioneering fields of engineering for electrostatic charging in systems are petro-chemistry and electrical engineering. Researchers in both fields attempted to formulate models to calculate the electrostatic charging a priori. These models provide some indication regarding the magnitude of charge but are currently not suited for the application in hydraulic systems. This is due to the lack of necessary fluid and material parameters for the application of either one of the models. [1, 2] Previous work in the pioneering fields focused on fluids and materials typical for their respective applications. This paper seeks to take the first step to remedy this situation by developing and commissioning a test bench for investigating a wide variety of hydraulic fluid-material combinations. The fluids pending investigation range from a typical hydraulic fluid based on a group I base oil to a pure polyalphaolefine of group IV. Common materials for hydraulic systems are investigated with a small scale test bench as well, such as steel and brass common to hydraulic applications as well as plastics and rubbers. In order to conduct these investigations a Searle viscometer is presented in this paper. In a Searle viscometer the cylinder is rotating while the cup or pipe remains stationary. Initially this paper gives the necessity for a small scale test bench using experimental results of an existing large scale test rig. Subsequently, the design of a small scale test bench, the Searle viscometer, will be presented along with a method for measuring the charge density. The small scale test bench is based on the work of Washabaugh and is able to generate the necessary information required for using the chemical reaction-based model [3, 4]. The main feature of the chemical reaction based model is the consideration for different material and fluid influences, beyond the scope of viscosity and system geometry.


2015 ◽  
Vol 18 (2) ◽  
Author(s):  
Almuhtarom Almuhtarom ◽  
Priyo Sasmoko

Almuhtarom, Priyo Sasmoko, in this paper explain that the existence of electrical energy for human needs can not be separated, the electrical energy used by all humans on this planet of small-scale (household) to large-scale industry. Demand the amount of electrical energy and the quality of the electricity transmission system has increased over time. Disruptions in electricity transmission system could be fatal for the electrical components or the operating loss in an industry. SCADA is proposed to accommodate this problem. SCADA is able to monitor and control the disturbances in electrical systems redundant. The purpose of this final project is to simulate a SCADA system to eliminate redundant electric power transmission network failures such as open-circuit, short circuit, and overload that can be controlled directly from the plant or via an interface on the computer. Ladder diagram programming languages ​​used to design the PLC system. Hardware and software to support this thesis, such as plant redundant electrical systems, Omron PLC CP1E NA-20-DRA, Laptop, CX One 9.3 software for programming the PLC and the CX Supervisor 3.1 for building HMI. The test results indicate that the current sensor can be used to detect if an interruption occurs in the form of overload and short circuit simulate disturbances. Plant redundant electrical system can be monitored and controlled through input-output of the plant, computer interface, and the World Wide Web. There is a relay on a plant that can connect to the electricity grid cut power lines when an interruption occurs. If an interruption occurs in the form of an open circuit, short circuit or overload, alarm and disturbance indicators will be active. Keywords: SCADA, PLC, open circuit, short circuit, overload


2021 ◽  
Author(s):  
Gareth Carter ◽  
Rhys Cooper ◽  
Joana Gafeira ◽  
John Howe ◽  
David Long

<p>Given the potentially devastating consequences of shallow submarine landslides on infrastructure and human lives, it is imperative that we understand potential slope stability issues within marine coastal regions. In Scottish waters, our lack of knowledge regarding the nature of the seabed within the fjords and coastal inlets is concerning given that these sea lochs have similar morphological features and settings to global examples (e.g. Norway) where recent slope failures have had such highly devastating results. Global examples from similar physiographic settings also demonstrate the temporal aspect of these events, highlighting that they are caused by active modern processes and therefore represent contemporary geohazards. In addition, previous studies have highlighted that there tends to be a scale bias towards the mapping and reporting of large-scale events, and there is a requirement for studies that focus on small-scale (≤1 km<sup>3</sup>) mass movements which can still have damaging consequences on seafloor and coastal (both nearshore and onshore) infrastructure.</p><p>In this study, a review of multibeam echo sounder (MBES) survey datasets from five locations around the United Kingdom northwest coast has led to the identification of a total of 14 separate submarine mass movement scars and deposits within the fjords (sea lochs) and coastal inlets of mainland Scotland, and the channels between the islands of the Inner Hebrides. In these areas, Quaternary sediment deposition was dominated by glacial and glaciomarine processes. Analysis of the morphometric parameters of each submarine mass movement has revealed that they fall into four distinct groups of subaqueous landslides; Singular Slumps, Singular Translational, Multiple Single-Type, and Complex (translational & rotational) failures. The Singular Slump Group includes discrete, individual subaqueous slumps that exhibit no evidence of modification through the merging of several scars. The Singular Translational Group comprise a single slide that displays characteristics associated with a single translational (planar) failure with no merging of multiple events. The Multiple Single-Type Group incorporates scars and deposits that displayed morphometric features consistent with the amalgamation of several failure events of the same type (e.g. debris flows or slumps). Finally, the Complex (translational & rotational) Group comprises landslides that exhibited complex styles of failures, including both translational and rotational mechanisms controlling the same slide. The submarine mass movements that comprise this dataset are then discussed in relation to global fjordic and glaciomarine nearshore settings, and slope failure trigger mechanisms associated with these environments are described with tentative links to individual submarine landslides from the database, where appropriate. It is acknowledged that additional MBES data are needed not only to expand this database but also to create a more statistically robust study. However, this initial study provides the basis for a much wider investigation of submarine mass movements and correlations between their morphometric parameters.</p>


2000 ◽  
Vol 45 (4) ◽  
pp. 396-398
Author(s):  
Roger Smith
Keyword(s):  

2020 ◽  
Vol 1 (1) ◽  
pp. 1-10
Author(s):  
Evi Rahmawati ◽  
Irnin Agustina Dwi Astuti ◽  
N Nurhayati

IPA Integrated is a place for students to study themselves and the surrounding environment applied in daily life. Integrated IPA Learning provides a direct experience to students through the use and development of scientific skills and attitudes. The importance of integrated IPA requires to pack learning well, integrated IPA integration with the preparation of modules combined with learning strategy can maximize the learning process in school. In SMP 209 Jakarta, the value of the integrated IPA is obtained from 34 students there are 10 students completed and 24 students are not complete because they get the value below the KKM of 68. This research is a development study with the development model of ADDIE (Analysis, Design, Development, Implementation, and Evaluation). The use of KPS-based integrated IPA modules (Science Process sSkills) on the theme of rainbow phenomenon obtained by media expert validation results with an average score of 84.38%, average material expert 82.18%, average linguist 75.37%. So the average of all aspects obtained by 80.55% is worth using and tested to students. The results of the teacher response obtained 88.69% value with excellent criteria. Student responses on a small scale acquired an average score of 85.19% with highly agreed criteria and on the large-scale student response gained a yield of 86.44% with very agreed criteria. So the module can be concluded receiving a good response by the teacher and students.


2019 ◽  
Vol 61 (1) ◽  
pp. 5-13 ◽  
Author(s):  
Loretta Lees

Abstract Gentrification is no-longer, if it ever was, a small scale process of urban transformation. Gentrification globally is more often practised as large scale urban redevelopment. It is state-led or state-induced. The results are clear – the displacement and disenfranchisement of low income groups in favour of wealthier in-movers. So, why has gentrification come to dominate policy making worldwide and what can be done about it?


2020 ◽  
Vol 9 (2) ◽  
Author(s):  
Bùi Thị Bích Lan

In Vietnam, the construction of hydropower projects has contributed significantly in the cause of industrialization and modernization of the country. The place where hydropower projects are built is mostly inhabited by ethnic minorities - communities that rely primarily on land, a very important source of livelihood security. In the context of the lack of common productive land in resettlement areas, the orientation for agricultural production is to promote indigenous knowledge combined with increasing scientific and technical application; shifting from small-scale production practices to large-scale commodity production. However, the research results of this article show that many obstacles in the transition process are being posed such as limitations on natural resources, traditional production thinking or the suitability and effectiveness of scientific - technical application models. When agricultural production does not ensure food security, a number of implications for people’s lives are increasingly evident, such as poverty, preserving cultural identity, social relations and resource protection. Since then, it has set the role of the State in researching and building appropriate agricultural production models to exploit local strengths and ensure sustainability.


2018 ◽  
Vol 1 (3) ◽  
pp. 156-165 ◽  
Author(s):  
Nasirudeen Abdul Fatawu

Recent floods in Ghana are largely blamed on mining activities. Not only are lives lost through these floods, farms andproperties are destroyed as a result. Water resources are diverted, polluted and impounded upon by both large-scale minersand small-scale miners. Although these activities are largely blamed on behavioural attitudes that need to be changed, thereare legal dimensions that should be addressed as well. Coincidentally, a great proportion of the water resources of Ghana arewithin these mining areas thus the continual pollution of these surface water sources is a serious threat to the environmentand the development of the country as a whole. The environmental laws need to be oriented properly with adequate sanctionsto tackle the impacts mining has on water resources. The Environmental Impact Assessment (EIA) procedure needs to bestreamlined and undertaken by the Environmental Protection Agency (EPA) and not the company itself.


2013 ◽  
Vol 14 (2) ◽  
Author(s):  
Noor Fachrizal

Biomass such as agriculture waste and urban waste are enormous potency as energy resources instead of enviromental problem. organic waste can be converted into energy in the form of liquid fuel, solid, and syngas by using of pyrolysis technique. Pyrolysis process can yield higher liquid form when the process can be drifted into fast and flash response. It can be solved by using microwave heating method. This research is started from developing an experimentation laboratory apparatus of microwave-assisted pyrolysis of biomass energy conversion system, and conducting preliminary experiments for gaining the proof that this method can be established for driving the process properly and safely. Modifying commercial oven into laboratory apparatus has been done, it works safely, and initial experiments have been carried out, process yields bio-oil and charcoal shortly, several parameters are achieved. Some further experiments are still needed for more detail parameters. Theresults may be used to design small-scale continuous model of productionsystem, which then can be developed into large-scale model that applicable for comercial use.


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