Transient Thermal‐Stress Analysis of Steel Slag Pots: Impact of the Solidifying‐Slag Layer on Heat Transfer and Wear

Abstract

The containers used for steel slag transportation to the recycling depot undergo hightemperature gradients and often deform plastically. Also, parts of the thereby solidified slag adhere to the pot walls, causing demolding problems and wear. A thorough finiteelement analysis of the heat transfer, initiated by filling the pots and essentially driven by radiation, and the thermal stresses is performed. Due to periodic fill-in and discharge, these are assumed to admit a quasi-stationary state referring to the pot temperature before their emptying. The so obtained results aid optimizing the pot shape and the transport process in terms of minimizing maintenance and anti-adhesive cladding. A layer of solidified slag is found to exist throughout the transport process. Although the phase change occurs almost instantaneously at a liquid-solid interface, the "mushy zone" is considered in the accompanying analytical study of the associated Stefan-type problem. Good correlations of the predicted temperatures to the measured ones and the resultant surface damaging are obtained.

Determining the thermally-stressed state of motor-driven bowls for transporting liquid slag

“…When studying the thermally stressed state of the motor-driven slag bowl, the peculiarities of the transition of slag from a liquid to a solid state were not taken into account, which is very carefully described in works [3,4]. Attention to the issue of determining temperature stresses at the boundaries of liquid and solid media was carefully consid-ered in [7,8]. Studies [8,9] report more specific measures regarding how the design of the bowl should be improved.…”

“…Paper [7] describes both analytical research results and experimental results using optical pyrometers. It is shown that the maximum temperatures when filling the cup reach 500 °С.…”

“…Work [10] reports the results of studies on the stressedstrained state of slag rail-mounted bowls. Separately, important experimental studies of the temperature field of bowls using a thermal imager with an optical pyrometer should be noted, conducted by analogy with work [7]. But, as in most cases, the cited studies are valid for not motor-driven bowls, and the issue of localization of maximum stresses is not sufficiently disclosed in the work.…”

“…At the same time, in all the cited works, the slag bowls had a unique design. In the design of the bowl in [7], no attention was paid to the supporting pins. The bowls described in works [2,5,6,10], by their design, are installed with four brackets on a support ring, they have different volumes and different design features.…”

Shaping of Ductile Cast Iron Dedicated for Slag Ladle

“…1) belong to the group of massive and thick-walled casts. Their shaping microstructure (during crystallization) is significantly different from the castings with smaller dimensions, which in turn consequently can lead to elements segregation and shrinkage porosity [1][2][3][4][5][6][7]. Crystallization of heavy-section casting affects the final quality of cast iron castings, because off its wall thickness and longer cooling time.…”