Road maintenance and cleaning in winter are performed with ploughshares. Due to the fact that the layer of snow and ice that is removed from the road surface contains various hard impurities, ploughshares are exposed to high intensity abrasive wear. This article deals with the resistance to abrasive wear of originally used ploughshare materials and the materials that were designed as a suitable modification of the ploughshare to increase its service life. The chemical composition of materials used to manufacture ploughshare components is unknown. For this reason, they were analyzed with an ARL 4460 spectrometer, which was used to analyze the element content. The main part of the research was focused on the abrasion resistance test, which was performed according to the GOST 23.208-79 standard. Based on the chemical analysis, it was found that the basic body of the ploughshare was made of S355J2G3 steel, and the raking blade material was made of 37MnSi5 steel. The original material (steel S355J2G3) of the ploughshare body as a reference standard was compared to steel HARDOX 450. Furthermore, a sample made of the original material of the raking blade (steel 37MnSi5) was used as a reference standard, the properties of which were compared to the newly designed OK 84.58 and UTP 690 hardfacing materials. The parametric test method of statistical hypotheses was also used to process and evaluate the weight losses of the selected materials.

Five different alloy hardfacings on 16MnCr5 grade low-carbon ferritic–pearlitic steel were investigated in terms of their abrasive wear resistance in laboratory testing conditions. The selected hardfacing materials, namely “E520 RB”, “RD 571”, “LNM 420FM”, “E DUR 600”, and “Weartrode 62”, were individually deposited onto plain ground-finish surfaces of 10 mm thick steel plate samples. The studied hardfacings were fabricated using several different welding methods and process parameters proposed by their industrial manufacturers. In the present comparative study, the results obtained from laboratory abrasive wear tests of the investigated hardfacings were analyzed and discussed in relation to their microstructure, hardness, and wear mechanism characteristics. Regardless of great variety in microstructure and chemical composition of individual hardfacing materials, the results clearly indicated the governing factor for the wear resistance improvement to be the overall carbon content of the used hardfacing material. Thus it has been shown that the “E520 RB” hardfacing exhibited the highest abrasive wear resistance thanks to its appropriate hardness and beneficial “ledeburite-type” eutectic microstructure.

The paper describes the surface roughness measurement of functional parts of tools for minting coins. The coining dies were coated with three types of coatings - CrN, TiCrN and WC/C. Roughness of the coining die surface is a very important fac...

This paper presents a utilization of mulcher tools, their wear and possibilities of increasing their lifetime and durability based on analysis and tests. Mulcher tools are subjected to a very strong wear causing the loss of soldered WC tips in some cases and even permanent deformation of the body tool made of steel 14 220 (16MnCr5) during the continuous use. Images depicting the loss of material from the mulcher tool due to wear were produced by overlaying the pre- and after-wear tools by means of the optical scanning system. Input analyses - measuring of hardness, impact test and evaluating of microstructure showed that forging is without heat treatment. This does not provide sufficient mechanical properties to tools that would ensure work continuation after losing WC tips. Therefore, an appropriate process of heat treatment of the tool body has been proposed. By comparing the loss of material using abrasive test, it was observed that the wear of heat-treated material was three times lower than of material without heat treatment. This gives the precondition for increasing the resistance of the tool body and thus increasing of lifetime and durability after loss of WC tips. The implementation of such a solution could bring not only technical but also economic benefits.

This paper presents the results of the quality evaluation of the weld joints on welded pipes used in industrial energy. The quality evaluation of the weld joints was performed by two methods. Using technical methods, welding faults and defects were examined, identified and evaluated by a metallographic analysis on the macrostructure of welds. According to ISO 6520-1:2007, the faults and defects were detected and classified into the group and classified into quality levels using ISO 5817:2008-03. Two quality management tools using a Cause and effect diagram - Iskihawa diagram and a Pareto diagram also evaluated the quality control of welds. These two tools enabled to identify the causes of welding defects as well as to determine the frequency of their occurrence and to identify the most serious welding faults and defects. Both methods - technical and management, should reveal shortcomings in both technical, technological and personnel aspect. Their use should contribute to improving the welding process of pipes in operation and to increasing the safety of piping systems.