The tool durability is a crucial factor in each manufacturing process, and this also includes the extrusion process. Striving to achieve the higher product quality should be accompanied by a long-term tool life and production cost reduction. This article presents the comparative research of load and wear of die at various angles of working cone during the concurrent extrusion. The numerical calculations of a tool load during the concurrent extrusion were performed using the MSC MARC software using the finite element method (FEM). Archard model was used to determine and compare die wear. This model was implemented in the software using the FEM. The examined tool deformations and stress distribution were determined based on the performed analyses. The die wear depth at various working cone angles was determined. Properly shaped die has an effect on the extruded material properties, but also controls loads, elastic deformation, and the tool life.

Keeping inventory is often a prerequisite for the functioning of the production and commercial companies as well as multiple service providers. The level of inventories, as well as charges depends on salesbut the charges are the result of sales (charges are the result of sales, while sales volume is also dependent on debt management strategies), and the stocks precede the sales; they are one of the conditions. The stocks should be adjusted to the expected sales. In the article there have been presented the ABC and XYZ analyses in the application of inventory management exemplified by an office stationery company. The ABC analysis for inventory shows that a relatively small number of items and the storage unit are the most important or predominant part in all of their value. The classification system allows to include the stored position into three groups according to the relative importance or value of the items making up the group. The XYZ analysis shows the differences between the goods in stocks and the used ones. The Z elements are used in a very irregular way and therefore, the size of the supply is unpredictable. For those parts there should be chosen a good supplier where the delivery time is short, so as to be able to rely on small batches of fast deliveries just in time.

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The purpose of warm forming is to reduce the deformation resistance, and therefore the formation of products at reduced pressures. A key problem associated with warm sheet metal forming is uniform heating of the material to a required temperature. This task is carried out mostly by using resistance heating plates. The article presents the results of the analysis of the thermal state of a heating plate for induction heating of an AMS 5604 stainless steel sheet. To determine the temperature distribution on the sheet surface an FLIR P 640 thermal imaging camera was used. It was found that the temperature difference on the outer surface of sheets preheated to the temperature of 900°C was about 300°C. A large difference in the temperature on the outer surface of the sheet means that the analysed device cannot be successfully used in the heating process of stainless steel sheets. After the application of a layer of graphite on the sheet surface to increase the emissivity, areas of low emissivity as a result of graphite detachment from the sheet surface were observed.

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