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The dryer feed chute of the pellet plant plays an important role in the pelletizing process. The chute discharges sticky and moist iron ore fines (<1 mm) to the inline rotary dryer for further processing. Since the inception of the installation of the dryer feed chute, the poor flowability of the feed materials has caused severe problems such as blockages and excessive wear of chute liners. This leads to high maintenance costs and reduced lifetime of the liner materials. Constant housekeeping is needed for maintaining the chute and reliable operation. The purpose of this study is to redesign the dryer feed chute to overcome the above challenges.

The discrete element method (DEM) has been used to model the flow of cohesive materials through the transfer chute. Physical experiments have been performed to understand the most severe flow conditions. A DEM material model is also developed for replicating the worst-case material condition. After identifying the key problem areas, concept designs were proposed and simulated to assess the design improvements to increase the reliability of chute operation.

Flow simulations correlated well with the existing flow behavior of the iron ore fines inside the chute. The location of the problematic areas has been validated with that of the previously installed chute. Subsequently, design modifications have been proposed. This includes modification of deflector plate and change in slope and cross-section of the chute. DEM simulations and analysis were conducted after incorporating these design changes. A comparison in the average velocity of particle and force on chute wall shows a significant improvement using the proposed design.

Method to calibrate DEM material model was found to provide accurate prediction and modeling of the flow behavior of bulk material through the real transfer chute. DEM provided greater insight into the performance of the chute especially modeling cohesive materials. DEM is a valuable design tool to assist chute designers troubleshoot and verify chute designs. DEM provides a greater ability to model and assess chute wear. This technique can help in achieving a scientific understanding of the flow properties of bulk solids through transfer chute, hence eliminate challenges, ensuring reliable, uninterrupted and profitable plant operation. This paper strongly advocates the use of calibrated DEM methodology in designing bulk material handling equipment.

The purpose of this paper is to show how particle scale simulation of industrial particle flows using DEM (discrete element method) offers the opportunity for better understanding of the flow dynamics leading to improvements in equipment design and operation.

The paper explores the breadth of industrial applications that are now possible with a series of case studies.

The paper finds that the inclusion of cohesion, coupling to other physics such fluids, and its use in bubbly and reacting flows are becoming increasingly viable. Challenges remain in developing models that balance the depth of the physics with the computational expense that is affordable and in the development of measurement and characterization processes to provide this expanding array of input data required. Steadily increasing computer power has seen model sizes grow from thousands of particles to many millions over the last decade, which steadily increases the range of applications that can be modelled and the complexity of the physics that can be well represented.

The paper shows how better understanding of the flow dynamics leading to improvements in equipment design and operation can potentially lead to large increases in equipment and process efficiency, throughput and/or product quality. Industrial applications can be characterised as large, involving complex particulate behaviour in typically complex geometries. The critical importance of particle shape on the behaviour of granular systems is demonstrated. Shape needs to be adequately represented in order to obtain quantitative predictive accuracy for these systems.

IN a recent Money programme on BBC TV Sir Monty Finniston was seen advocating the need for greater investment in industry as opposed to money being sent abroad to be invested either in Japanese industry or American real estate.

Known throughout the world, the Martin‐Baker Company has become an organisation whose sole business is the design, development and production of escape systems. These include ejections seats, command ejection systems, canopy jettison, miniature detonation cord, automatic inflation of liferaft and life vest, and all the related sub‐systems that are required by an aircraft design team. Thousands of lives have been saved in conditions varying from high altitude emergencies to those occurring while an aircraft is still on the ground during its take‐off run. Escape from VTOL aircraft is also a valuable asset as has been shown in successful ejections from uncontrollable situations that have arisen with these types. RAF and Royal Navy aircraft have been equipped with Martin‐Baker systems for many years, and among overseas customers, the US Navy has been using them from the early days.

Among component‐feeding devices, none has yet proved a significant rival to the vibratory feeder. But a new Swedish device may do so. Brian Rooks reports.

The purpose of this paper is to identify key tasks, tools, and equipment associated with maintenance and repair injuries at US mines and to provide some mitigation strategies to reduce these types of injuries.

This study analyzed incidents resulting in injuries reported to the US Mine Safety and Health Administration from 2002 to 2011. Incident reports were limited to those occurring at mining plants, shops, yards, and aboveground locations. Incident reports were analyzed to determine which activities contributed to injuries and were due to machine maintenance and repair, non-powered hand tools, and powered hand tools. An in-depth analysis of the root causes of these injuries was then performed.

Maintenance and repair in mining is associated with a significant number of hand and finger injuries with a range of severities and averaging over 20 amputated fingers, 180 fractured hands and fingers, and 455 hand and finger lacerations per year. Many of these injuries are caused by hands being struck by or caught in tools and equipment. Back and shoulder strains are found to be associated with the most days lost from work and are mostly attributed to materials handling.

Occupational injuries and fatalities still occur with high incidences in the mining sector. The mission of the Office of Mine Safety and Health Research (OMSHR; part of the National Institute for Occupational Safety and Health, NIOSH) is to “eliminate mining fatalities, injuries, and illnesses through research and prevention.” As part of this work, OMSHR acquires surveillance data from MSHA to quantify the types and sources of injuries at US mining facilities. The authors evaluated maintenance- and repair-related injuries at US mining sites (excluding underground coal mines). Results of this study suggest a need for improved design of machine guarding, improved hand protection through gloves and equipment design/redesign, and manual materials handling solutions.

The findings indicate that maintenance and repair in mining include occupational risks that may be managed through modifications to machines, proper usage of hand tools and hand protection, and improved manual materials handling processes.

THE firm of Jessop‐Saville Ltd., which dates back to 1774, has become well established as a supplier of special steels and alloys. Their progress in this field has been maintained only by continual research and a readiness to adopt new techniques and equipment.

Sliding wear is a common phenomenon in the iron ore handling industry. Large-scale handling of iron ore bulk-solids causes a high amount of volume loss from the surfaces of bulk-solids-handling equipment. Predicting the sliding wear volume from equipment surfaces is beneficial for efficient maintenance of worn equipment. Recently, the discrete element method (DEM) simulations have been utilised to predict the wear by bulk-solids. However, the sensitivity of wear prediction subjected to DEM parameters has not been systemically investigated at single particle level. To ensure the wear predictions by DEM are accurate and stable, this study aims to conduct the sensitivity analysis at the single particle level.

In this research, pin-on-disc wear tests are modelled to predict the sliding wear by individual iron ore particles. The Hertz–Mindlin (no slip) contact model is implemented to simulate interactions between particle (pin) and geometry (disc). To quantify the wear from geometry surface, a sliding wear equation derived from Archard’s wear model is adopted in the DEM simulations. The accuracy of the pin-on-disc wear test simulation is assessed by comparing the predicted wear volume with that of the theoretical calculation. The stability is evaluated by repetitive tests of a reference case. At the steady-state wear, the sensitivity analysis is done by predicting sliding wear volumes using the parameter values determined by iron ore-handling conditions. This research is carried out using the software EDEM^® 2.7.1.

Numerical errors occur when a particle passes a joint side of geometry meshes. However, this influence is negligible compared to total wear volume of a wear revolution. A reference case study demonstrates that accurate and stable results of sliding wear volume can be achieved. For the sliding wear at steady state, increasing particle density or radius causes more wear, whereas, by contrast, particle Poisson’s ratio, particle shear modulus, geometry mesh size, rotating speed, coefficient of restitution and time step have no impact on wear volume. As expected, increasing indentation force results in a proportional increase. For maintaining wear characteristic and reducing simulation time, the geometry mesh size is recommended. To further reduce simulation time, it is inappropriate using lower particle shear modulus. However, the maximum time step can be increased to 187% T_R without compromising simulation accuracy.

The applied coefficient of sliding wear is determined based on theoretical and experimental studies of a spherical head of iron ore particle. To predict realistic volume loss in the iron ore-handling industry, this coefficient should be experimentally determined by taking into account the non-spherical shapes of iron ore particles.

The effects of DEM parameters on sliding wear are revealed, enabling the selections of adequate values to predict sliding wear in the iron ore-handling industry.

The accuracy and stability to predict sliding wear by using EDEM^® 2.7.1 are verified. Besides, this research accelerates the calibration of sliding wear prediction by DEM.

This paper describes the design and development of a re‐configurable dual‐robot assembly system using off‐the‐shelf re‐configurable pneumatic modules, Hall‐effect sensors, a vision system, and a programmable logic controller (PLC). Each robot arm consists of three sets of pneumatic modules and a pneumatic gripper. Each module consists of a pneumatic housing, an air cylinder, and a Hall‐effect sensor, and provides one degree of freedom. Solenoids are used to redirect airflow and thereby extend and/or retract the air cylinder. A vision system is used for fixture inspection. A conveyor and part stopper are designed to transfer and stop pallets. All these modules, the gripper, the part stopper, and the vision system are controlled and synchronized using a PLC. At the end of this paper, a framework for making the system over the Web for remote operation and diagnosis is proposed and described.

THE change in the Institute's title has been accomplished very quietly, as if it were a matter of minor importance, the mere substitution of some words for others. If it were no more than that it would scarcely justify the time and trouble which it involved.