Skew Rolling of Bimetallic Rods

The present article reports selected results of a preliminary study of the process of skew rolling of bimetallic rods. The experiments were conducted using a numerically controlled three-roller skew rolling mill. During the tests, bimetallic rods were rolled from billets whose cores and outer sleeves (bushings) were made of different types of steel. The results demonstrate that the proposed method can be successfully used in the production of bimetallic rods. However, proper fastening of the two materials depends on the geometrical parameters of the billets, and the quality of bimetallic rods depends on the heating method used. When the rods are heated without protective atmospheres, the surface layer of the core gets decarburized and the surfaces of the materials being joined together are oxidized, which hinders the welding process and adversely affects the physical and chemical properties of such products. The results of numerical modeling indicate that the material near the surface tends to flow, which may have a negative impact on the welding process. In addition, the distribution of stress in the tool–workpiece contact zone may make welding of the materials difficult. The results reported in this paper are preliminary and constitute a prelude to a more detailed analysis of bimetallic rod rolling.

A Wire Rod Rolling Mill Digital Twin for the Simulation of the Rolls Replacement Process

Smart Manufacturing is a goal to be achieved, and the most advanced manufacturing approaches are being used to pursue this objective. Within this context, industry development aims to attain an intelligent manufacturing using, for example, virtual models that simulate production lines. This paper presents the architecture of a Digital Twin for emulating the rolls replacement process within a wire rod rolling mill. The model is developed in Python, using a backtracking algorithm to select the suitable set of rolls as a first basic approach for the validation of the system. It may be used in the future to improve the production system automating the decision for the replacement of rolls as alternative to the current human-decision process.

Ensemble of surrogates and cross-validation for rapid and accurate predictions using small data sets

In engineering design, surrogate models are often used instead of costly computer simulations. Typically, a single surrogate model is selected based on the previous experience. We observe, based on an analysis of the published literature, that fitting an ensemble of surrogates (EoS) based on cross-validation errors is more accurate but requires more computational time. In this paper, we propose a method to build an EoS that is both accurate and less computationally expensive. In the proposed method, the EoS is a weighted average surrogate of response surface models, kriging, and radial basis functions based on overall cross-validation error. We demonstrate that created EoS is accurate than individual surrogates even when fewer data points are used, so computationally efficient with relatively insensitive predictions. We demonstrate the use of an EoS using hot rod rolling as an example. Finally, we include a rule-based template which can be used for other problems with similar requirements, for example, the computational time, required accuracy, and the size of the data.

Methods of reducing-sizing block finishing passes form optimization aimed at accuracy improving of finished profile geometric dimensions

Accuracy of hot-rolled products dimensions is one of main indices of quality and along with strength and structure metal characteristics, determines quality and competiveness of the hot-rolled products. Increase of rolling accuracy enables to make the rolled products in “minus” area of tolerance and to save metal at the expense of a profile running metre mass decreasing. It is possible only at rolling in accurately calculated finishing passes, manufactured according to adjusted rolling accuracy and with outlets of optimal form. Analysis of calibration efficiency application accomplished, the calibration being of “oval–circle” version with application of three-radius construction of reducing-sizing block round passes of wire rod rolling mill at production of 5.5 mm diameter wire rod. A numeral model elaborated for production of 5.5 mm diameter wire rod at a wire-rod mill using a base sizing “oval–circle”. To study geometric dimensions of 5.5 mm diameter wire rod, manufactured at 150 mill with application of “oval– circle” base sizing, samples of 80K steel were collected. The selection was done out of the head and of the tail of a coil. Based on energy-power data and speed parameters of a real rolling process, a mathematic model of 5.5 mm diameter wire rod rolling with application “oval–circle” base sizing was constructed. Wire rod mill 150 finishing gages form optimization was accomplished aimed at an increase of geometric dimensions of final profile accuracy. Analysis of efficiency of multi-radius cutting of finishing stands rolling passes was done for production of 5.5 mm diameter wire rod.

An Inverse, Decision-Based Design Method for Integrated Design Exploration of Materials, Products, and Manufacturing Processes

A material's design revolution is underway with a focus to design the material microstructure and processing paths to achieve certain performance requirements of products. A host of manufacturing processes are involved in producing a product. The processing carried out in each process influences its final properties. To couple the material processing-structure-property-performance (PSPP) spaces, models of specific manufacturing processes must be enhanced and integrated using multiscale modeling techniques (vertical integration) and then the input and output of the various manufacturing processes must be integrated to facilitate the flow of information from one process to another (horizontal integration). Together vertical and horizontal integration allows for the decision-based design exploration of the manufacturing process chain in an inverse manner to realize the end product. In this paper, we present an inverse method to achieve the integrated design exploration of materials, products, and manufacturing processes through the vertical and horizontal integration of models. The method is supported by the concept exploration framework (CEF) to systematically explore design alternatives and generate satisficing design solutions. The efficacy of the method is illustrated for a hot rod rolling (HRR) and cooling process chain problem by exploring the processing paths and microstructure in an inverse manner to produce a rod with specific mechanical properties. The proposed method and the exploration framework are generic and support the integrated decision-based design exploration of a process chain to realize an end product by tailoring material microstructures and processing paths.

PDSIDES—A Knowledge-Based Platform for Decision Support in the Design of Engineering Systems

We hypothesize that by providing decision support for designers we can speed up the design process and facilitate the creation of quality cost-effective designs. One of the challenges in providing design decision support is that the decision workflows embody various degrees of complexity due to the inherent complexity embodied in engineering systems. To tackle this, we propose a knowledge-based Platform for Decision Support in the Design of Engineering Systems (PDSIDES). PDSIDES is built on our earlier works that are anchored in modeling decision-related knowledge with templates using ontologies to facilitate execution and reuse. In this paper, we extend the ontological decision templates to a computational platform that provides knowledge-based decision support for three types of users, namely, template creators, template editors, and template implementers, in original design, adaptive design, and variant design, respectively. The efficacy of PDSIDES is demonstrated using a hot rod rolling system (HRRS) design example.