This article presents the application of the ring-on-ring test to investigate some of the important factors affecting the abrasive and corrosion wear of a face seal used in the sugar industry. The test involves the sliding contact between two steel rings working in different conditions such as mechanic, abrasive, corrosive extortions and its combination. Rings were made of the C45 steel and the surface layers were modified by heat and thermochemical treatment such as normalizing, flame hardening, nitriding and chrome diffusion. Maximum wear of the sample after tests under mechanic, abrasive and corrosion extortion were obtained. For C45 steel without surface modification the biggest wear was obtained for mechanical, abrasive and corrosive extortion and equals 0.0138 g. This value was three times bigger than the result for the mechanical extortion and ten times than for the corrosive conditions. For individual research options the percentage increase or decrease in wear resistance in relation to the normalized surface layer was determined. In the corrosive extortion the highest increase (90%) of wear resistance was recorded for the chrome layer relative to normalizing sample. The main conclusion of the paper is that the wear effect caused by all factors—mechanical, abrasive and corrosive—is not a straight sum of values of wear.

The paper presents laboratory tests results of wear in the abrasive mass of cultivator coulters subjected to coated electrode pad welding. In the first stage of the test, one type of electrode was used and a padding weld was applied to the coulter surface in three different shape variants (perpendicular, parallel to the abrasive mass stream and V-shaped). The lowest abrasive wear was obtained for samples with a padding weld deposited perpendicularly to the abrasive mass stream. Therefore, in the second stage of the research, this padding weld shape was selected and made using three different electrodes. Tests of abrasive wear both in the first and the second stage of the experiment were carried out at a distance of 100 km by the "rotating bowl unit" method. Both the direction of the application of the padding weld (shape) and the chemical composition of the electrode used in the pad welding process significantly increased the resistance to abrasive wear compared to coulters whose surface has not been welded.

Elements of belt conveyors, like other machine parts, are subject to wear processes. The conveyors transporting the spoil in the quartz sand mine are exposed to accelerated wear due to the effect of quartz on metal elements. Intensive wear of metal parts leads to downtime and the need to replace damage parts which generates additional costs. Therefore, it is important to perform surface treatment of metal elements, which will allow to extend the operation time of belt conveyors by reducing wear. The main objective of the article is to determine the impact of the pad welding process of the surface layer of metal elements on the abrasive wear of elements working in the metal–quartz sand–rubber conditions used in belt conveyors. In this research study, three different types of electrodes were used for pad welding the surface. The wear results obtained on the test stand were compared to wear of the basic element without surface treatment. The average wear value of the samples padded with electrode 3 was about 25% lower than the samples without surface treatment. The main mechanism of sample wear was the abrasion process due to the interaction between the steel surface and hard sand particles. The results presented in the article are important not only for belt conveyor elements but also for other machine parts where it is desirable to reduce abrasive wear.

Cultivators are machines used among others to open and smooth out the surface of the ploughland and to mix mineral fertilizers with soil. The article presents a design of a cultivator mounted on an agricultural tractor with a power of up to 20 kW. The main design assumption mainly focuses on keeping the weight of the device low, while ensuring the required durability. Moreover, the design makes it possible to attach it to the three-point linkage in a category 1 tractor. The drafted design was subjected to the MES analysis, according to which, the maximum travel of the cultivator frame does not exceed 1.3 mm, and the stress typically reaches the level of 40 MPa and does not exceed the stress permissible for the E295 steel. An analysis of the costs of manufacturing the cultivator was also performed and on its basis, it was found that the price should not exceed PLN 1,800.

The paper presents the studies and results of the Shore hardness and scratch test of polymer materials used in medical devices. Polymers of organic PMMA (poly(methyl methacrylate)) origin for the manufacture of orthodontic appliances were tested. Samples of test materials differed in manufacturing technology. The surface functional properties of four materials were compared. Hardness tests were performed with the Shore D hardness test method. The scratch test was done with a Rockwell diamond cone indenter. The hardness was also calculated from the scratch test. Shore's highest hardness was demonstrated in 1A material. But the differences in Shore's hardness were small. Larger differences between the tested materials were shown in the scratch test than in the Shore hardness test. The lowest residual scratch depth (Rd) was obtained for 1A material. 3A material had the highest scratch hardness.