Machinery Arrangement Research Articles

A Human Factors Approach to Improve Layout Design for A Virtual Reality-based Training Platform

In manufacturing industries, equipment arrangement, and layout design are critical factors that directly influence productivity, workplace safety, and workers’ performance. Link analysis, as a human factors approach, has been widely used in industries for many years to improve layout design and machinery arrangement. This approach considers humans' physical and cognitive capabilities and movement limitations to find an optimal design. Virtual reality significantly impacts our society from product design to worker training. Hence, effective virtual training platforms require the same attention to layout design as manufacturing work settings which offer efficient testing of multiple layouts. This research focuses on developing a virtual 3D printing laboratory for workforce training and has used a link analysis and user perception study to improve the layout of the virtual workplace. The research demonstrates the importance of layout design in virtual training platforms and the potential benefits of utilizing link analysis in optimizing layout design.

Machinery Outfitting to Meet SOx Regulations - Function Design and Machinery Arrangement

Machinery Outfitting to Meet SOx Regulations - Function Design and Machinery Arrangement

Geostatistical Modeling of Overburden Lithofacies to Optimize Continuous Mining in the Ptolemais Lignite Mines, Greece

Lignite production in Greece is implemented mainly by the Public Power Corporation (PPC), with the higher production being in the Lignite Center of Western Macedonia. A continuous surface mining method is used in order to satisfy the high production needs combined with the necessity for selective mining; however, the occasional appearance of hard rock formations in the South Field mine overburdens was critical for the adoption of a discontinuous auxiliary method of rock mass removal, at these places, by explosives and large shovels. Furthermore, to minimize the delay of changing the machinery arrangements when a hard rock formation is met, an a priori knowledge of the spatial distribution of these rock masses would be catalytic. In this work, a plurigaussian simulation model of the overburden geological formations is developed in the South Field mine. This model could be used as a guide to schedule and optimize the overburden removal process. Validation of the model was affected in two ways: by direct comparing estimated to real cross-sections as observed on mine slopes or by correlating PPC’s recorded volumetric results to the average simulated hard rock percentages.

WHAT NEEDED TO HYBRID? MARINE PROPULSION GREENING PRINCIPLES

Greening and hybrid propulsion are being more and more common on the market. Apparently, looking to propulsion machinery arrangement and recognizing electric motor and batteries reflects a green propulsion system for the first while. However, being green it doesn’t mean only the electric motor and batteries. The greening is mainly about energy utilization and optimization in sequence layers. This means greening concept as a start layer(s) has a direct connection to what is power configuration on board and what propulsion system available and how to utilize the available power to the specified propulsion. As a next layer(s), the optimization can be enhanced by utilizing digitalization possibilities to adopt system dynamically for the most optimum hybrid condition. The paper is going through this process where explaining optimization differences between different propulsion systems for being more and more green.

Active Vibration Isolation of a Diesel Generator in a Small Marine Vessel: An Experimental Study

An active vibration isolation system is retrofitted to a diesel generator set in a tugboat to determine the effectiveness of such a system in a realistic practical environment. The system consists of six bespoke inertial actuators chosen to make minimal modifications to the machinery arrangement, and a DSP-based controller. Six accelerometers are collocated with the actuators on the top of six isolators to act as error sensors, and six accelerometers are placed below the isolators to give a measure of the global vibration of the ships structure below the generator set. A hydrophone is also placed in the water to give an indication of the underwater noise due to the generator. The control strategy employed is six-input and six-output decentralized adaptive feedforward control with the reference signal being derived from the signal from an optical tachometer on shaft between the engine and the generator. To suppress the vibration at all the dominant forcing frequencies, an electrical circuit generated the half engine orders required from the measured reference signal. The experimental results show that the combination of the active control system and the passive isolators is effective in reducing the global vibration and the acoustic pressure at the hydrophone position.

Non-Destructive Testing and Diagnostic of Rotating Machinery Faults in Petrochemical Processing Plant

Machinery fault detection as part of predictive maintenance based on the machine vibration has been practiced comprehensively in oil and gas industry and power generation plant for maintaining the reliability of the machineries. Despite the advantages, the efforts of identifying machinery fault earlier may lead to inaccurate interpretation and diagnosis due to lack of knowledge, skill and experience. Conventional vibration data acquisition and analysis using single axis accelerometer are time consuming. Therefore, an approach which relies on the visualisation of machine vibration motion technique is proposed. The visualisation of machine vibration motion was performed through a simplified Operating Deflection Shape (ODS) analysis. ODS analysis on a 4 measurement points is enough to show the motion of general machinery arrangement which consist of 2 bearings on the drive side and another 2 bearings on the driven side. The effectiveness of the simplified technique was tested in a laboratory condition before being applied in oil and gas industry. The results show vibration data acquisition is more efficient and time saving by using tri-axis accelerometer and relative phase technique. Furthermore, machinery fault diagnosis can be identified easily, faster and more accurate through visualising the machine vibration motion using a simplified 4-point ODS. This simplified technique is seen as practical approach to be proposed and integrated into conventional machinery fault detection and predictive maintenance based on the machine vibration.

Latest technologies and novel approaches in coal seam gas centrifugal compressor trains in Australia

Latest guidelines, novel technical notes, new technical knowledge and recent lessons learned are discussed for emerging market of coal seam gas (CSG) centrifugal compressor trains. Optimum configurations and novel arrangements for coal seam gas (CSG) centrifugal compressor trains driven by gas turbines are addressed. Untreated and saturated nature of CSG need special considerations. Operation, performance, degradation, reliability and maintenance issues of centrifugal compressors, gas turbines, gear units and couplings are also explained. The focus is on new technical knowledge, latest experiences and recent lessons learned on these topics. New recommendations regarding centrifugal compressor train components, gas turbines, machinery arrangement, auxiliaries, gear units, lubrication oil systems, bearings, casing and condition monitoring are also presented. A case study is discussed.

A process modelling approach to the evaluation of ship machinery configuration alternatives of LNG carriers

The increasing seaborne transportation of Liquefied Natural Gas (LNG) in the current volatile global market and energy supply environment puts a pressure on LNG vessels to be more efficient, environmentally friendly, and cost-effective. Modern LNG carriers feature complex and tightly integrated machinery systems to convert the onboard primary energy sources to useful energy demands for propulsion, electricity and heat. Therefore, process modelling and simulation techniques combined with an integrated systems approach is required for the evaluation of different configuration alternatives of LNG carriers. In this paper, we used our in-house process modelling framework DNVGL COSSMOS to develop a generic model of an LNG carrier integrated machinery system encompassing various propulsion and energy recovery technologies. The resulting system model was then coupled with a generic operational profile description accounting for various operating modes and intended trading routes of the vessel. The integrated LNG carrier machinery process model was subsequently used for the evaluation of different technology alternatives and machinery configurations. Namely, the model was used to size the gas-fuel compression trains; assess the introduction and optimal size of an LNG reliquefaction plant; compare electric and mechanical propulsion technologies; and, assess the introduction of energy recovery technologies such as shaft generators and exhaust gas economisers. The model-based studies resulted in an improved insight of this complex integrated machinery arrangement, revealing important performance trade-offs and interrelations between the vessel’s sub-systems. The results revealed high energy savings potential between 5 to 8% depending on the energy recovery options implemented, operating profile and trading route.

A SIMPLIFIED TECHNIQUE TO DISTINGUISH UNBALANCE AND MISALIGNMENT USING FREQUENCY DOMAIN OPERATING DEFLECTION SHAPE

Machinery fault can be identified by performing Condition-Based Monitoring (CBM) program which rely on the machinery vibration data. However, the data which represented by the time wave and vibration spectrum requires technically trained personnel to understand and diagnose. In this research, a simplified technique through visualization of the Operating Deflection Shape (ODS) is proposed. The technique combines both the data of vibration amplitude and phase measurement. An ODS of a general machinery arrangement can be visualized from 4 measurement points. The technique is performed and tested in laboratory condition. Future CBM program should implement this technique because it helps untrained personnel to be able to distinguish primary machinery fault such as unbalance and misalignment easily by visualizing the machine motion.

Feasibility and Design Implications of Fuel Cell Power for Sealift Ships

Fuel cell technologies provide clean and efficient power solutions for both stationary and mobile applications. For shipboard applications, most studies published so far have focused on ship service power or on propulsion power for small vessels with moderate power requirements. Using a military sealift vessel as the platform, this project aims at investigating the implications of implementing fuel cells as the primary power source on a large military cargo ship. A notional solid oxide fuel cell (SOFC) module is proposed and the implications of the technology on fuel savings and machinery arrangements are analyzed. The study shows that, by using a hybrid SOFC–GT (gas turbine) system, high system efficiency can be achieved through combined power–heat–steam generation within the constraints of the given machinery space. The modular features of the fuel cell systems and electrical components are also exploited for flexible machinery arrangements. This paper documents the quantitative analysis of the fuel cell-powered sealift vessel, provides detailed space arrangement schematics for the proposed concept, and identifies the technology gaps and future development opportunities to pursue the next generation of clean and efficient military sealift vessels or commercial cargo ships.

Evaluation Criterion of Machinery Arrangement Design in a Ship Engine Room

The aim of this study is to establish an objective evaluation function that can be used to compare alternative layouts by employing the quantification of particularities of arrangements in ship design. The arrangement of the machinery parts in a ship's engine room is decided at the design phase along with the location of various types of equipment that are located in a compartment. The design needs to maximize the function of every component, while taking into consideration the limited space of the ship. The addition and modification of requirements frequently occurs during the development process of a ship. Therefore, the ship designer suggests several alternative layouts, though only one layout is selected for the final design. This process depends on the experience, knowledge, and judgment of an expert designer, and it is consequently difficult to objectively evaluate the ship design. Therefore, according to quantification by using the fuzzy theory, we suggest a standard that can objectively evaluate alternative layouts to determine the most successful design. In order to provide a standard of evaluation, several evaluation functions are considered and established. By observing the results of the proposed method, the effectiveness of the proposed method is discussed. The results proved the convenience of the location of equipment in the space and the minimum size of the arrangement space in the engine room as well as the interrelationship between each type of equipment. Also, the proposed method showed the pipe producibility in ship building. As a result, the proposed method will contribute to reduce the production cost of ships.

Fuzzy approach for assessment of machinery arrangement

Fuzzy approach for assessment of machinery arrangement

Improvement of Hull Form of Fishing Vessel by Suitable Bulge

Fishing boats have several restrictions on their machinery arrangements and space utility on deck. For the improvement of the stability and the deck utility, the fitting of a bulge on sidewall of the vessel is one of the solutions. However, the bulge generally makes a significant increase of hull resistance and loss of speed.At the principal design stage of the elongation of the fisheries research ship“Ushio-maru”, the University of Hokkaido, the authors examined the suitable form of the bulge to improve the stability without increase of the hull resistance. For this purpose, systematic calculations of wave making resistance by Rankine's source method and model experiments using a circulating water channel have been conducted. In this process, it has been found that the optimized bulge form can decrease the hull resistance.In this paper, the authors discuss about the mechanism of the hull resistance decrease by a bulge based on the view point of flow field around hull and propose the suitable method to design the bulge form. Thistechnique has been applied to the actual elongation design of“Ushio-maru”, and then it has been confirmed by the experimental model tests as well as the full scale trials.

퍼지모델링을 이용한 기관실 장비 배치 평가

The aim of this study is to establish an evaluation function that can be used in comparison of alternative layouts by quantification of particularities of arrangements. The machinery arrangement is a design phase that decides the location of various equipment in a compartment to make the most of the function of every components and to meet the limit of ship space at the same time. In case of the ship, Only one of the several alternative layouts is selected. This process depends on the experience, knowledge, and judgement of an expert and, as a result of it, it`s hard to get an objective evaluation. Therefore, according to quantification by using the fuzzy theory, we suggest a standard that can objectively evaluate alternative layouts.

Selection of the Power Plant for an Alaskan RO/RO Ship

In 1996 TOTE began a Maritech project with NASSCO aimed at looking at replacement tonnage for their existing fleet of steamships. The Maritech study started with a single-screw, slow-speed diesel ship that in essence would have been a lengthened Pfeiffer containership. Between the capacity and speed requirements of the trade, it became evident that a twin-screw ship was required with greater beam than the Pfeiffer. It was also clear that the short run of the ships heightened the relationship between port time and sea speed, and that from a cargo load and discharge time, certain machinery arrangements were more favorable than others. The original 17 power plant options were reduced to four options that were studied in detail. This paper endeavors to document the decision process and the economic and operational comparisons that were made.

Applying Fuzzy Functions and Sequential Coordination to Optimization of Machinery Arrangement and Pipe Routing

ABSTRACT Ship design is often multidisciplinary involving several design elements with various types of objectives and constraints (O/C), some easily described as mathematical formulas, others better modeled as descriptive assertions. This paper describes a method based on fuzzy functions and an integrated performance index to model O/C using descriptive assertions to be used with mathematical formulas in optimization. Another issue addressed in this paper concerns the coordination of design elements when sequentially coupled, that is, when one leads the other and the performance of the follower depends greatly on the design of the leader. Based on neuro‐fuzzy techniques, the method described here coordinates and optimizes sequentially coupled elements. The two methods are applied to machinery arrangement (MA) and pipe routing (PR). Preliminary models for optimization of MA and PR are described considering convenience, producibility, engine room size, interference and location as factors in the O/C set. Some test results from MA/PR applications are presented and discussed. The methods are generic and can be extended to other elements in ship design. They are mutually independent and may be used separately. Two advantages of their use are an improvement in overall performance and a reduction in the need for redesign of elements.

SWATH Research Vessel: The Building of RV Western Flyer

The design of the SIVA TH (small waterplane area, twin hull) research vessel Western Flyer is described. Because the Flyer is intended to serve as mother-ship for an advanced deep-diving ROV (remote-operated vehicle) to be deployed in CaliJbrnia's Monterey Bay area, the SWATH configuration presents a safe and stable pla(form [kom which to operate in practically all weather conditions. Launch and retrieval of the ROV./?om the sheltered moonpool, or centerwell, are discussed as well as the elaborate 7'ether Alanagement System. The deck and machinery arrangements" are illustrated, and model tests to predict the SWA TH's station keeping qualities and pitch motions in various sea states are described.

Machinery arrangements for small Vtol transport aircraft

SummaryAircraft plying between urban and outlying communities usually enjoy a runway with noise restrictions at the urban end and perhaps little to land on at the other end, but with no objection to noisy operation. The existence of this situation in northern Canada persuaded the National Research Council to embark — some thirty years ago — on an investigation of powered lift possibilities, with strong support from the trunk and regional airlines, the charter and helicopter operators, and various manufacturers.From a number of generic lift-propulsion arrangements examined in greater or lesser detail, a selection are described here in increasing order of what the certifying authorities call “damage tolerance” or reduced dependence on “critical parts”. Freedom from demands for hovering endurance and quietness, combined with emphasis on small aircraft, offered encouragement to attack what is otherwise a very difficult task. Of the alternatives, only one, which incorporated transverse axis fans and the light weight gas turbines now available, emerged as a potentially satisfactory choice for small rugged transport aircraft.The project was discontinued because of pressure of other work, but is recounted here in case others may discern wider market possibilities. A small Vtol aircraft should, if successful, be a useful precursor to sophisticated airliners capable of taking off and landing without a run.

GINQUAL: A cotton processing quality model

Mathematical relationships for each seed cotton ( Gossypium hirsutum) cleaning machine type used in the cotton ginning process were developed to predict changes in foreign matter content and moisture levels as a function of the condition of the cotton entering the machine, the environmental conditions and the operating parameters for each machine. These relationships were combined, along with other functions found in the literature for tower driers, ginstands and lint cleaners into a digital simulation model, GINQUAL, for stripper harvested cotton. GINQUAL predicts grade and value as a function of foreign matter content and color levels of ginned lint. Selected processing rates, initial moisture contents and operating parameters can be specified in the model. Cotton quality, quantity and moisture content are tracked for each machine type in the gin processing system, which can include various combinations of the following: an airline cleaner, a drier, an inclined cleaner, a stick machine, a bur machine, a combination stick and bur machine, an extractor-feeder-cleaner, a ginstand and multiple lint cleaners. The model was validated by using a wide range of cotton types with varying amounts of foreign matter, moisture and gin machinery arrangements. The predicted trash content values at the feeder apron, and the predicted nonlint content after two lint cleaners, were not significantly different from the observed values in the historical validation data set, indicating that the model can be used to examine different processing sequences and operating parameters for potential improvement in quality.

A DISCIPLINED APPROACH TO MACHINERY ARRANGEMENTS IN SHIP DESIGN

ABSTRACTThis paper presents an overview of the machinery arrangement function as an integral part of the ship design process. It discusses an iterative process of arriving at a machinery arrangement that meets the demanding requirements of naval ship operation, maintenance, and survivability within the constraints of a balanced ship design. Examples of the various tradeoffs and variables impacting machinery arrangements at each design phase are provided to illustrate the complex problem of producing a balanced design. This paper also briefly discusses the tools available to design or to critically evaluate alternative arrangements and to assess the impact of structural and hull changes as the ship design matures.