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The purpose of this paper is to investigate the scope of reliability improvement of aluminium wire rolling mill. This paper addresses the performance reliability of continuous process industry of interest to many applications in maintenance planning where multi-attribute decision making (MADM) approaches are very useful. The paper addresses the process of discriminating critical components through substantial shop-floor failure data. The research work narrates a method for evaluating risk priority number (RPN) traditionally. Moreover, the maintainability criticality index (MCI) for each failure cause of identified critical components is evaluated through two disparate MADM failure models: technique for order preference by similarity to ideal solution (TOPSIS) and preference section index (PSI) to overcome the limitations of more traditional approaches. The primary findings of this research work are to enhance quality in planning the maintenance activities of critical components of targeted process industry through traditional as well as nontraditional failure analysis models. The research work is focused on potential failure causes of critical components like; bearings, gears, and shafts of aluminium wire rolling mill which are commonly representing the most critical components in a large range of industrial processes including aluminium wires. The proposed work will illustrate the working lives of components and associated failures. It will help to elucidate maintenance issues of major process industries and recommended deliverable keys. [ABSTRACT FROM AUTHOR]

The present article addresses hydrodynamic bearings performance in high-speed modules of wire rolling mills and is searching for the possibilities to increase the reliability of their work. In order to determine the performance parameters of hydrodynamic bearings, such as the minimum thickness of the lubricant film, the friction coefficient and the temperature of the lubricant heating, we used the calculation method based on the standard method as the parameters depend on the main production and operational factors. This allowed us to reveal that the most important factors are the speed and the temperature of the lubricant input while the load and the lubricant input pressure affect the parameters of the bearings to a small extent. At the lubricant input temperature of more than 85°C, there is a risk of the bearing damage in the last unit modules due to the violation of the laminar flow conditions. According to the results of the analysis, it is recommended to keep the input temperature of lubricants within the range of 60–80°C. The observance of the proposed recommendations for existing bearing design and actual technological parameters enables the longer operation life of the module, reduction in the downtime related to the need for repairs, and reduction in the repair expenses. [ABSTRACT FROM AUTHOR]

Based on the slab method, a three-dimensional analytical solution is first proposed to calculate the rolling pressure, force, and torque in asymmetrical wire rolling where the work rolls radii, their peripheral speeds, and the interfacial frictions may be different. Since the lateral spread cannot be ignored in the wire rolling process, the plain strain condition is not applicable. Moreover, the shear and normal stresses in the vertical sides of the element are considered to be distributed linearly. The effects of process parameters such as reduction in height, rolls peripheral speed ratio, and friction factor ratio on the processes output, like pressure distribution, rolling force, and lateral spread are investigated. Moreover, the commercial finite element code, ABAQUS, is used in this study to model the asymmetrical wire rolling. The selected analytical results were compared with FEM simulation data to verify the effectiveness of the developed model. By this proposed analytical solution, it is noted that the computer expense and calculation time can be saved, and the characteristics of asymmetrical wire rolling are obtained simply and quickly. [ABSTRACT FROM AUTHOR]

ABSTRACT In hot forming processes at elevated temperatures like wire rolling, microstructural changes such as repeated dynamic recrystallisation and grain growth occur. An experimental method to obtain the flow stress behaviour and to capture the recrystallised microstructure for materials subjected to large deformations, high temperatures between 900 and 1200 °C and high strain rates around 5000 s− 1 is presented. The method is based on the split-Hopkinson pressure bar arrangement complemented with an inductive heat source. Furthermore, a momentum trap is added to ensure that the specimen is loaded only once. By quenching the specimen directly after the single loading, the dynamically recrystallised microstructure is preserved. The quenching is performed within 0.1 s of loading by dropping the specimen into a water bath. By applying the momentum trap technique, the compressive loading of the specimen could be interrupted at a strain level slightly above the strain level corresponding to the peak stress, which is a good estimation for the onset of dynamic recrystallisation. [ABSTRACT FROM AUTHOR]

The drive system of a winding machine, mounted on the production line of a wire rolling mill, must perform at the same time driving in a rotary motion of the drum on which the wire is wound and linear displacement of the wire reeling device. On the dynamic performance of the operation of this system depends largely the quality of wire winding in the coils delivered to the beneficiaries, reducing losses caused by re-melting the wire improperly wound and productive capacity of the mill. This system is usually of two types: electromechanical, based on variable speed electric motor and ball valve screw or electro-mechano-hydraulic, without control loop, based on variable speed electric motor, speed reduction gear and hydraulic drive system on-off type. Typically, the drum which the wire is wrapped around is operated electromechanically for both types of systems, and the reeling device, which moves linearly, along the drum, the wire coming out of the mill, is driven by a ball screw, for the first type, or hydraulically, without control loop, for the second type. The authors of this material have developed and put into operation an electro hydraulic servomechanism for driving the reeling head that allows controlling its position and speed by means of an electro hydraulic control loop. [ABSTRACT FROM AUTHOR]

Examines the applicability of a set of grooves of multi-roll wire mills for different materials having different stress-strain curves. Evaluation of stability of geometry among different materials when rolled under the same mill setting conditions; Influence of inter-stand tension upstream side four-stand tandem rolling.