Showing papers on "Material flow published in 1999"

Material flow behavior during friction stir welding of aluminum

Abstract: Friction stir welding (FSW) is a new technique for joining aluminum alloys. Invented in 1991 at The Welding Institute (Ref. 1), this technique results in low distortion and high joint strength compared with other techniques, and is capable of joining all aluminum alloys. To date, the majority of research has concentrated on developing the tools and procedures for making reliable welds in a variety of alloys, on characterizing the properties of welds and on developing design allowables (Refs. 2-7). However, very little is known about material flow behavior during welding. The purpose of the current study is to document the movement of material during friction stir welding as a means of developing a conceptual model of the deformation process. In this paper, two new techniques for visualizing material flow patterns in friction stir welds are presented. Based on measured results in welds of 6061 and 7075 aluminum, material movement within friction stir welds is by either simple extrusion or chaotic mixing, depending on where within the weld zone the material originates. These results impact the development of welding procedures and suggest ways to model the process for predicting welding tool performance.

Using the Information Decoupling Point to Improve Supply Chain Performance

Abstract: Traditionally, the decoupling point methodology has been associated with the material flow pipeline. However, to maximize improvement in supply chain dynamics, information flow is equally important. Many of the problems exhibited in the material flow pipeline are the result of the distortion of marketplace sales information as it is transferred upstream through the supply chain. This research expands on the traditional material decoupling point methodology and establishes the role of an information decoupling point within the supply chain. The authors demonstrate the business opportunities generated by first recognizing the existence of the supply chain information decoupling point and then learning how to utilize it to gain strategic advantage. In order to make sensible planning and delivery decisions, a business must be able to separate out contingency from real orders as they move upstream from the marketplace. It is the basis for supply chains moving towards continuous flow and away from point‐to‐point movements and ultimately, where appropriate, to holistic control.

Material and inventory control system for a demand flow process

Abstract: A material flow design system for a mixed-model demand flow manufacturing line is presented. The material flow system utilizes a replenishment card/replenishment container system of material management. The material flow design system defines the size of replenishment containers and the location of material deduct points in the production path. The material flow design system may further include a design system for designing an inventory control system. The inventory control system involves locating backflush and intermediate backflush locations on the production path and deduct points in the material flow sequence. An inventory monitoring system monitors material flow, deducts material from inventories at deduct points, and credits material to inventory indicated by the deduct points when products produced by the manufacturing line flow through material backflush points defined in the manufacturing line.

Performance Analysis of Flow Lines with Non-Linear Flow of Material

Abstract: Introduction.- Issues, Goals, and Methods of Flow Line Analysis.- Variability and the Performance of Flow Lines.- Non-Linearities in the Flow of Material.- Economic Design Problems in Flow Line Analysis.- Methods of Performance Analysis.- Two-Machine Decomposition of Flow Lines.- Review of the Literature.- Assembly/Disassembly Systems with Random Processing Times.- Discrete and Continuous Time Models.- Exact Solution of a Two-Machine Subsystem.- Decomposition Equations for Assembly/Disassembly Systems.- Two Algorithms to Determine Performance Measures.- Numerical Results.- Optimal Design of Assembly/Disassembly Systems.- Flow Lines with Rework Loops and Identical Processing Times.- Discrete-Material Flow Line Model with Identical Deterministic Processing Times.- Decomposition Equations for Loops and Identical Processing Times.- The Algorithm to Determine Performance Measures.- Numerical Results: Algorithms and Flow Line Behavior.- Optimal Design of Systems with Loops and Identical Processing Times.- Flow Lines with Rework Loops and Machine-Specific Processing Times.- Continuous-Material Flow Line Model with Machine-Specific Processing Times.- Decomposition Equations for Loops and Different Processing Times.- The Algorithm to Determine Performance Measures.- Numerical Results: Algorithms and Flow Line Behavior.- Optimal Design of Systems with Loops and Different Processing Times.- Conclusions and Suggestions for Further Research.- Derivation for the Discrete Material Flow Line.- Derivation for the Continuous Material Flow Line..

Material Flow-based Indicators in Environmental Reporting

Abstract: NOTE The contents of this report do not necessarily reflect the official opinion of the European Communities or other European Communities institutions. Neither the European Environment Agency nor any person or company acting on the behalf of the Agency is responsible for the use that may be made of the information contained in this report.

Flow control system for spray applications

Abstract: A spray control system for applying a coating composition to an object. The control system includes an applicator, flow control valve, flow meter, and an electronic controller connected to the valve and flow meter. The controller regulates the flow of coating composition to maintain it at a user-specified setpoint. The controller includes a learn mode in which it learns the proper valve setting for a particular setpoint and stores a valve control signal that is later used at the start of a spray application to initially set the valve at the proper position. Then, once the flow of material begins, the controller uses either incremental or proportional control, or both, to maintain the flow at the specified setpoint. When learning a setpoint, the controller also stores the current values of a number of user-specified process parameters, such as ambient air temperature and the coating composition source pressure. These stored parameter values are then monitored during the spray application and an alarm notification is provided if they drift outside of a window about their stored values. The controller is configured to adapt to changing environmental and operational conditions by re-learning the proper valve setting for a particular setpoint each time the flow sufficiently stabilizes at the setpoint. Circuitry is also disclosed for use in connection with the flow meter to quickly determine the flow rate at the commencement of material flow and to provide fast updating of a conventional digital readout of flow rate.

Rheological analysis of ceramic pastes

Abstract: This paper is concerned with a number of means of characterising the rheological properties of a ceramic paste. The intrinsic flow behaviour of the paste, during upsetting, is studied experimentally by using multi coloured paste samples, as well as by a finite element numerical computation. The flow behaviour of the paste is approximated by an elasto-viscoplastic material constitutive model and implemented by using an established finite element code. The material flow properties, which are necessary for the implementation of the numerical model, were obtained using the squeeze film and hardness indentation test configurations. The flow fields generated by the simulation are shown to be a good accord with the experimental observations. The experimental procedure for selecting the material parameters which are necessary for the implementation of the numerical model is described. The accuracy of the numerical method described is also evaluated by comparing the simulation results with experimental data obtained from the net upsetting force against the imposed relative displacement behaviour and the flow visualisation of deformed coloured layers. In these respects, a comparison of the finite element model predictions and the experimental results demonstrates a good mutual agreement.

Material Intensity of Transportation and Implications for Sustainable Mobility in Europe

Abstract: In general transport is regarded today as one of the ecologically most critical sectors of our economy. However, up to now studies focused mainly on the emissions caused by the various transport modes (VIA 1990; HOpfner et al. 1993; Hassel et al. 1995, Mailbach et al. 1995), whereas the material intensity has been rather neglected. Therefore, in the following paper the material intensity of transportation will be analysed. In the beginning, the concept of material intensity analysis and its methodology will be introduced. Thereafter, results for the material intensity of infrastructure, vehicles and their use for various transport categories will be presented. Finally, the implications for a more sustainable mobility will be discussed.

Process mass flow apparatus and method for measuring the mass flow of powdered and granulated solids as well as the accumulated weight of material passed during a specified time

Abstract: A process mass flow apparatus for measuring the mass flow rate of a powdered, granulated or otherwise substantially divided process solid, seeds, grains, or similar particulate materials includes a process material inlet, a process material outlet, a measuring chamber connecting the process material inlet and the process material outlet, comprising a movable element with a fixed axis of rotation located in the flow path of the process material and having attached to the axis of rotation a material flow sensor which provides a raw output signal corresponding to an unknown mass flow rate and a processor which contains an empirically derived calibration function for converting the raw output signal to an adjusted signal indicating the mass flow rate of the process fluid. A method is also disclosed for determining an unknown mass flow using an empirically derived conversion function, the function being derived by correlating the output signals of a mass flow instrument sensing the flow of a calibration material with the output signals of the mass flow instrument sensing the flow of the process material, as is a method for calculating the accumulated weight of material having passed through the measuring chamber during a period of time specified by the user.

STREAMS: a new method for analysing material flows through society

Abstract: For the development of material, product and waste oriented policies, knowledge about the flow, use and disposal of materials through society is necessary. The risks of taking policy measures leading to suboptimum solutions of environmental problems call for an integral survey of material flows through society. However, up to now, integral analyses of physical material flows have been lacking. Problems such as differences in definitions, in subdivisions of flows and in reference years make it difficult to relate data from different sources to obtain an overall view. In this article, STREAMS, a new method to calculate physical material flows through society, is proposed. The method is based on the so-called supply and use tables, which describe a country’s economy in terms of supply and use of materials, products and services by industries, service sectors and consumers. In our approach, materials and products are tracked on their way from extraction of raw materials to the final consumption of products and beyond, into the stage of waste. The method has the advantage of deriving almost all data from one source. In this article the method is described. In a separate study, the method is applied to obtain an integral survey of the flow of plastics through The Netherlands, showing that the method can be used to assess the final materials consumption on a highly detailed level.

Method and apparatus for a coriolis flowmeter having its flow calibration factor independent of material density

Abstract: A single tube Coriolis flowmeter of enhanced flow sensitivity in which material flow induces Coriolis deflections in a flow tube and Coriolis-like deflections in a balance bar vibrationally coupled to the flow tube. Both the Coriolis deflections and the Coriolis-like deflections have a phase shift determined by material flow and are used co-adjuvantly to derive material flow information. The flowmeter achieves a constant flow sensitivity over a range of changes in material density by 1) varying the flow sensitivity in a first direction under control of the ratio between the drive mode vibration amplitude of the flow tube and the balance bar and 2) varying the flow sensitivity in an opposite direction under control of the ratio between the Coriolis deflection amplitude of the flow tube and the Coriolis-like deflection of the balance bar. The drive mode vibration amplitude ratio varies with changes in drive mode frequency caused by changes in material density. The amplitude ratio of the Coriolis deflection and the Coriolis-like deflection changes with changes in the magnitude of the separation of the drive mode frequency and the second bending mode frequency to the balance bar density which, in turn, is caused by changes in material density.

Dispensing mechanism with dual function flow regulator and sealing plate

Abstract: A flow regulator for controlling the flow of material from a container (12) is disclosed, wherein the container includes a container outlet (14) through which the material freely flows when the container outlet is not closed. The flow regulator is biased in a closed position, but is moveable to an open position to provide for material flow from the container. The flow regulator may be progressively moved to permit varying degrees of material flow as the opening in the container is progressively opened. The flow regulator provides both a closure to obstruct material flow and a seal to preserve the container contents from outside contamination or degradation. The flow regulator is disclosed in combination with a bulk bin container to form a novel dispensing mechanism.

Chip carrier module has cut-outs forming large-area setting material holders with boundary forming setting material flow barrier, bridges mechanically connecting adjacent contact areas

Abstract: The module has a non-conducting flat carrier (2) with contact areas (4) on its underside partially open to the top via cut-outs (10,12,14). An IC chip (6) mounted on a chip holding point is electrically connected to at least one exposed contact area via bonded wires (13) and the chip and wires are embedded in a setting material (20). At least one or a few of the cut-outs are in the form of large-area setting material holders whose outer boundary forms a flow barrier for the setting material, whereby bridges (15-17) between these cut-outs mechanically connect adjacent contact areas.

Cellular machine layout based on the Segmented Flow Topology

Abstract: This paper introduces a facility layout design procedure for converting an existing manufacturing system with a predefined aisle structure to a cellular manufacturing system based on the 'segmented flow topology' (SFT) developed by Sinriech and Tanchoco The proposed procedure is aimed at finding the best machine grouping, along with the locations of pick-up and delivery stations and machine layout for each cell based on an existing facility The objective is to minimize the total material handling cost In contrast to previous work in this area, the proposed design procedure takes into account both distance and material flow in forming machine clusters In addition, a revised cost model for material handling system, which accounts for different aspects of capital and operating cost, is presented

Analysis of an improved width-flow concept for the production of ribbed strips by cold rolling

Abstract: In today's increasingly competitive business environment, companies must look for innovative solutions to survive the competition. In the metal forming industry the engineers are turning to new technologies in order to achieve the goals. One new innovative process is the macroscopic structuration of strips by cold rolling for use in light-weight constructions. Components with a macro-structured surface demonstrate - on the condition of equal weight - a higher area moment of inertia and consequently a higher stiffness than non-structured workpieces. The subjects presented in this paper refer to ribbed sheets produced in a cold-rolling process. Particularly the material flow into the rib pocket is studied in a simplified model as a function of different set-up parameters like tool geometry, deformation, and friction. The theoretical investigations are carried out by the upper-bound theory. The results are compared with an FEM-analysis.

Liquid material gasifying apparatus

Abstract: PROBLEM TO BE SOLVED: To efficiently gasify a liquid material having complicated gasification characteristics as a material of a high dielectric substance and prevent clogging in an apparatus and a pipe arrangement, by providing a liquid material flow path, a gasification flow path and a heating mechanism, and causing the heat receiving area per unit liquid quantity of the gasification flow path to be not less than a specified quantity. SOLUTION: A material container 12 for housing a liquid material L and a material transportation tube 14 connected thereto are provided. Downstream of a flow controller 18 along the material transportation tube 14, a gasification preventing section 20 is provided. Just after the section 20 in the downstream, a gasifying section 22 for instantaneously gasifying the liquid material L by exposing the liquid material L to a high temperature and a low pressure is provided. Particularly, the gasifying section 22 has a heating section 36 of a jacket structure for housing a heat medium of a high temperature. In this heating section 36, the heat receiving area per unit liquid quantity is set to be not less than 2 (mm /mm ). Thus, it has a structure in which a fine tube for material transportation is inserted in a jacket 38.

Method of friction welding with mixing and permanent probe for use in friction welding

Abstract: FIELD: mechanical engineering; cold welding of structures with continuous longitudinal welds. SUBSTANCE: method of friction welding with mixing is based on increased flow of plasticized material in horizontal and vertical directions relative to adjoining assembly parts. Pressure is applied to forming plasticized material in direction perpendicular to surfaces of parts to be connected with simultaneous provision of material flow along probe pin in vertical direction. plasticized material hardens behind the probe. Permanent probe has concave lower part with interchangeable pin. Pin has thread-shaped outer surface. In preferred version it has two or more blades projecting across. EFFECT: provision of homogeneous welds without cavities and other defects in welds of different types. 7 cl, 9 dwg

Coriolis flowmeter having its flow calibration factor independent of material density, and method of operating it

Abstract: not available for EP1110059Abstract of corresponding document: WO0012970A single tube Coriolis flowmeter of enhanced flow sensitivity in which material flow induces Coriolis deflections in a flow tube and Coriolis-like deflections in a balance bar vibrationally coupled to the flow tube. Both the Coriolis deflections and the Coriolis-like deflections have a phase shift determined by material flow and are used co-adjuvantly to derive material flow information. The flowmeter achieves a constant flow sensitivity over a range of changes in material density by 1) varying the flow sensitivity in a first direction under control of the ratio between the drive mode vibration amplitude of the flow tube and the balance bar and 2) varying the flow sensitivity in an opposite direction under control of the ratio between the Coriolis deflection amplitude of the flow tube and the Coriolis-like deflection of the balance bar. The drive mode vibration amplitude ratio varies with changes in drive mode frequency caused by changes in material density. The amplitude ratio of the Coriolis deflection and the Coriolis-like deflection changes with changes in the magnitude of the separation of the drive mode frequency and the second bending mode frequency to the balance bar density which, in turn, is caused by changes in material density.

Stable-flow quantitative feeding machine

Abstract: The utility model discloses a stable-flow quantitative feeding machine. The utility model is provided with a motor, a speed reducer, a transmission shaft, a rotor cavity and a pressure equalizing cabin. The inner part of the rotor cavity is provided with a material distributing impeller, and the inner part of the pressure equalizing cabin is provided with a mixing arm and a material pushing plate. A partition plate is arranged between the rotor cavity and the pressure equalizing cabin. The partition plate is provided with a feed port, and the bottom plate of the rotor cavity is provided with a discharge port. The utility model feeds accurately in determined quantity, and overcomes the problems of an existing rigid impeller feeding machine or a screw feeder, such as unsteady material flow, large quantity fluctuation for feeding material, air leakage, material punching, material escaping, etc. The utility model is suitable for use in chemical industry and building material industry.

Optimization-based planning heuristic for material flow congestion avoidance in conveyor network design

Abstract: A model is developed to plan material flow congestion avoidance on a network of conveyors for handling discrete batches of items, e.g. scanned packages. Minimizing maximum material flow congestion is used as a guide to design the conveyor network by evenly distributing the flow of such batches by considering capacities of the conveyors and existing flow. Problems of this type are typically NP-hard which makes them unsolvable by standard mixed integer programming solvers. A method based on results from probability theory is used to solve the formulated problem. Experimental results are presented to demonstrate convergence within 10-100 iterations of the described method for most problems. The increase in CPU time is observed to be approximately linear with respect to the number of constraints and with respect to the number of binary variablesfor a constant number ofiterationsofthe algorithm. A procedure for estimation of bounds is derived to show the proximity of the obtained solution to an optimal solution.

Material treatment equipment, especially for cement raw material calcination, has a flow diversion chamber with an impact wall transverse to material flow entering from a rising pipe branch

Abstract: Material treatment equipment comprises a flow diversion chamber (2) with an impact wall transverse to material flow entering from a rising pipe branch (1). Equipment for material treatment, especially thermal and/or chemical treatment, comprises an upwards pipe branch (1), a diversion chamber (2) and one or more downwards pipe branches (3), an impact wall being provided in the diversion chamber and being positioned transverse to the flow direction of material entering the chamber through the upwards pipe branch.

Material spray humidizing device

Abstract: The utility model discloses a material atomizing and humidifying device, which is composed of a material flow control box and a mist and material mixing box which are connected, wherein, the lower part of the material flow control box is provided with a material flow gathering guide tube which is connected with the mist and material mixing box; the upper part of the mist and material mixing box is provided with an umbrella-shaped bulk material cover, and materials which flow down from the gathering guide tube are uniformly scattered in a screen curtain shape in the mist and material mixing box along the umbrella-shaped bulk material cover; a water mist sprayer is arranged below the umbrella-shaped bulk material cover. The utility model which has favorable humidifying effect not only can be used for humidifying the rice in a rice polishing machine, but also can be used for humidifying the multi-machine slightly ground rice in a milled rice machine set. The utility model even can spray and humidify other materials.