Uhryński Andrzej, Bembenek Michał
Faculty of Mechanical Engineering and Robotics, AGH University of Science and Technology, A. Mickiewicza 30, 30-059 Krakow, Poland.
Materials (Basel). 2022 Apr 14;15(8):2870. doi: 10.3390/ma15082870.
When the briquetting process of fine-grained material takes place in the roller press unit, the pressure reached is over a hundred megapascals. This parameter is a result, among other factors, of the geometry of a compaction unit and also the properties of the consolidated material. The pressure of the unit is not constant and the changes in value depend on a given place on the molding surface. By the process of generating different types of pressure on the surface of briquettes, their compaction is different as well. The distribution of temperature on the surface of the briquettes may determine the pressure used locally on them. Nevertheless, the distribution of stress in the briquetting material is still a subject of scientific study. However, it is known that the pressure exerted on the briquette is different for different compaction systems. The article includes authors' further thermography studies on the classical pillow-shaped briquetting process (instead of the saddle-shaped ones that were previously conducted) of four materials (calcium hydroxide and water mixture, mill scale, charcoal fines and starch mixture, as well as a mixture of EAFD, scale, fine coke breeze, molasses, and calcium hydroxide). Immediately after the briquettes left the compaction zone, thermal images were taken of them, as well as forming rollers. Thermograms that were obtained and the variability of temperature at characteristic points of the surface of pillow-shaped briquettes were analyzed. They showed differences in temperature on the surface of briquettes. In all four cases, the highest briquette temperatures were recorded in their upper part, which proves their better densification in this part. The temperature differences between the lower and upper part of the briquettes ranged from 1.8 to 9.7 °C, depending on the mixture.
当细粒物料在辊压机单元中进行压块过程时，所达到的压力超过一百兆帕斯卡。该参数是压实单元的几何形状以及固结材料特性等多种因素作用的结果。单元压力并非恒定不变，其数值变化取决于成型表面上的特定位置。通过在压块表面产生不同类型压力的过程，压块的压实程度也有所不同。压块表面的温度分布可能决定施加在其上的局部压力。然而，压块材料中的应力分布仍是科学研究的课题。不过，已知对于不同的压实系统，施加在压块上的压力是不同的。本文包含了作者对四种材料（氢氧化钙与水的混合物、氧化铁皮、木炭粉与淀粉的混合物，以及电弧炉粉尘、氧化铁皮、细焦粉、糖蜜和氢氧化钙的混合物）进行的经典枕形压块过程（而非之前进行的鞍形压块过程）的进一步热成像研究。压块刚离开压实区后，便对其以及成型辊拍摄了热图像。对所获得的热成像图以及枕形压块表面特征点处的温度变化进行了分析。结果显示压块表面温度存在差异。在所有四种情况下，压块上部的温度最高，这表明该部分的压实效果更好。压块下部和上部之间的温度差在1.8至9.7摄氏度之间，具体取决于混合物。
