Comparative studies of the classical and new design of a chaff cutter’s cutting drum have been conducted within the frames of the study in order to determine their functional characteristics at the time of cutting rye straw into pieces of specific length (into chaff). A classical design of a cutting drum is of the shape of a roller and is suitable for material layer cross-cutting. However, the new drum design has the shape of a double truncated cone and, with the use of it, diagonal cuts in two directions can be realized. The studies were conducted for four designs of cutting drums with cutting angles α = 0° (classical design) and α = 15°, α = 30°, and α = 45° (new design). Three indicators were applied for the assessment: capacity, unit energy consumption, and the unit cutting resistance. The obtained results show that the use of a new drum design makes it possible, depending on the assumed parameters of the cutting process and the material’s compaction degree, to increase the process’s efficiency by up to 25%, lower the unit energy consumption up to 34%, and lower the unit cutting resistance by up to 8%. The conducted experimental studies have unequivocally shown that the use of a new cutting drum design, as compared to the classical one, results in a considerable increase in the cutting process’s performance. Studies on the new design of a chaff cutter’s cutting drum, of the shape of a double truncated cone, belong to original ones that so far have not been described in the available literature.

This paper describes experimental research on cutting the outer layer of onions in the machine peeling process. The authors’ own globally innovative modular machine construction was used for this purpose. The onion peeling machine was constructed on a real scale. The effectiveness of the machine’s functioning $S_e$ was defined as the ratio of the mass of material correctly removed by the scale blower $m_p$ to the mass of all material leaving the machine on the test bench $m_c$. In order to carry out the experimental research, a test stand was constructed, a research plan and programme were adopted, and the research methodology was developed. The results obtained during the experimental research and the data obtained from the regression function equations for the developed design of the onion peeling machine were used to build systems of independent variables, for which the dependent variable $S_e$ reached extreme values. The effectiveness of the machine’s operation $S_e$ of modular construction increased with the increase in the depth of the external incisions of the shells $d_n$, the number of scale-blowing nozzles, and the pressure of the air supply to the scale-blowing unit $p$. Increasing the material feed rate $v_p$ and the distance of the air nozzles from the material to be processed $h_d$ reduced the machine’s efficiency $S_e$. The tests carried out showed a high level of efficiency on the level of $S_e=0.645-0.780$, which is not found in mass-produced machines.

The paper presents mathematical models describing the moments of resistance to cutting on the cutting drum shafts in the biomass cutting process. The mathematical procedures described in the paper have been verified on a test stand developed and constructed by the authors, which reflects real conditions of the process of cutting plant material into pieces of specified lengths. Experimental verification proved that the developed mathematical models are adequate for drums of both cylindrical and conical constructions. The value of the average error did not exceed 13%. Following the mathematical elaboration and verification studies, the authors carried out calculations for machines currently available on the market that are equipped with drum cutting units. The calculations were carried out for the most commonly cut material, i.e. for maize, straw and green plant materials. The obtained results confirm the complexity of the problem arising from a wide range of numerical values of cutting resistance, which is contained in the range of 400–1,800 nm. The compiled database can be practically applied in the selection of machines for specific field works, and the mathematical models developed and verified in the study can be applied at the stage of designing new designs of cutting drums used in forage harvesters.

An analysis of construction was conducted in this study, and the guidelines for designing roller mills used commonly in the agri-food, chemical, power and construction industries were presented. Quick designing of the machines required existence of adequate mathematical models. Within the framework of the study’s realization, a mathematical model was developed and we presented the selected results of calculations of the milling rollers loading from the assembly’s mill bowl. The simulation calculations conducted with the mathematical model unambiguously show that the roller’s rotation around a fixed point considerably influences the total loading of the mill’s bowl, and passing over that phenomenon is a mistake.

The aim of this study was to examine the functional characteristics of the process of cutting surgical gauze with a drum cutting unit. For this purpose, the authors designed and constructed a test stand on which experimental tests were conducted. As part of this study, the results of the experimental tests are presented, which were conducted for three selected thicknesses of surgical gauze samples, four selected angles of feeding of the material to be cut and nine selected cutting speeds. In order to determine cutting resistance, the specific cutting resistance was used, and the energy consumption was estimated using the specific cutting work related to the cutting surface of the surgical gauze. The conducted experimental studies demonstrated that the highest value of the specific cutting resistance $p_c=78.14 \mathrm{N}\cdot {\mathrm{m}}^{-1}$ occurred during the cutting of eight-layer gauze at a cutting angle $\alpha =0°$ and a cutting speed $V_c=0.66 \mathrm{m}\cdot {\mathrm{s}}^{-1}$. Meanwhile, the highest value of the specific cutting work was approximately $L_{jS}=120.00 \mathrm{J}\cdot {\mathrm{m}}^{-2}$ during the cutting of three-layer gauze, also at a cutting speed $V_c=0.66 \mathrm{m}\cdot {\mathrm{s}}^{-1}$ for cutting angles $\alpha =0°$ and $\alpha =5°$. This study found that $V_c=0.66 \mathrm{m}\cdot {\mathrm{s}}^{-1}$ is the threshold cutting speed at which the material is cut. Below this speed, the cutting drum does not have enough momentum to cut the material. Based on the statistical analysis of the obtained test results, it was concluded that there exists a relationship between the independent and dependent variables. The cutting speed has the greatest impact on the parameters of the surgical gauze cutting process. The test results, which have not been found in the worldwide literature to date, constitute a valuable contribution to the development of the theory of surgical gauze cutting. The experimentally determined specific cutting resistance p_c and specific cutting work of surgical gauze broaden the knowledge of the materials used in medicine and contribute to the expansion of scientific knowledge in this field.

This article describes the results of the studies related to the occurrence of the European corn borer (Ostrinia nubilalis Hbn) pest carried out at the Technical University of Bydgoszcz. The studies concerned the real occurrence of the pest in corn stubble (cultivated variety SY Collosseum). The research issue undertaken is in line with an IPM (integrated pest management) system and is important since the feeding of the European corn borer can lead to large, direct yield losses estimated nationally at an average of up to about 20%, which does not differ significantly from that of world crops. Corn, for the purposes of this study, was harvested for green fodder in September, and for grain in November 2022, using a John Deere X9 1110 harvester. The average stubble height when cut for green fodder was 280 mm, while for grain it was 265 mm. The experimental studies conducted clearly showed that European corn borer larvae colonized as much as 12% of corn samples harvested for grain at an average stubble height of 155 mm, and 19% of corn samples harvested for grain at an average height of 75 mm. The conducted studies also showed that the average diameter of the stems at the height of the residence of the corn borer larvae when harvested for green fodder is 19.80 mm, and 21.80 mm for grain. The studies conducted by the authors showed the randomness of the locations of the pest larvae, which clearly indicates that the generally known and used mechanical methods of its control are not fully effective. Therefore, the authors presented their own design of a machine construction (filed with the patent office of the Republic of Poland) for destroying the European corn borer in a mechanical way without the use of crop protection chemicals. The presented research problem in this paper is of national and global importance considering the fact that corn is grown on an area of nearly 162 million hectares, where we have to deal with the European corn borer pest. In the case of implementing the design of the construction of a machine for destroying the pest, there will be no need to use chemical pesticides, which will significantly contribute to environmental protection.