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The aim of this study was to determine the effects of different shank types, tine types, and tractor forward speeds on the power and fuel consumption of chisel plows, stubble cover, soil surface roughness, and penetration resistance. In addition, using the obtained results, the draft power, fuel consumption, soil surface roughness, and soil stubble cover rate were modeled using Deep Learning Neural Network (DLNN) architectures and sensitivity analysis of these models were performed. Four different shank types (rigid, semi-spring, spring, and vibrating) and two different tine types (conventional and winged) were used at three different tractor forward speeds (4.5, 5.4 and 6.3 km.h − 1 ) were tested to this end. The obtained results indicated that the maximum draft power was achieved with the rigid type shank. The highest soil surface roughness values were observed for the vibrating shank type and winged tine type. Sixteen different network architectures were conducted using deep learning neural network methods and draft power, fuel consumption, soil surface roughness, and percent stubble cover were modeled. Sensitivity analyses were performed to indicate which modeled parameters were more sensitive to the factors using the obtained models. Draft power was modeled with 97.7% accuracy using the DLNN9 network architecture. Additionally, fuel consumption and soil roughness were best modeled with the DLNN13 network architecture, R 2 values for those targets were 0.929 and 0.930 respectively. According to the sensitivity analysis, draft power, fuel consumption, soil roughness, and stubble cover rate were significantly affected by changes in the physical properties of the soil.

This article analyses ground stone discoveries from the late neolithic site of Pericei located in north-west of Romania, in Șimleu Depression. Combined characteristics of chisels and adzes in working process are discussed along with their context, especially those connected to stone working: the layer, dwellings and pebble agglomerations. We conclude that Pericei was a production center for stone chisels, appeared to supply the demand that until then was satisfied by Suplac/Porț site that continued to produce ground stone tools for a longer period. V članku analiziramo glajena orodja najdena na poznoneolitskem najdišči Pericei v severozahodni Romuniji v globeli Simleu. Razpravljamo o skupnih značilnostih in kontekstih dlet in tesel v delovnih procesih, predvsem tistih, ki so povezani z obdelavo kamna: kulturna plast, bivališče in skupki prodnikov. Sklepamo, da predstavlja Pericei center za proizvodnjo kamnitih dlet, ki je oskrboval območja, ki so bila do takrat oskrbovana iz najdišča Suplac/Port, kjer so proizvajali glajena kamnita orodja v daljšem časovnem obdobju.

Ball end mills have complex geometry. The precision CNC grinding of the cutting edge on the spherical surface is a big challenge for the tool manufacturers. Regarding the design cutting edge, we propose a cutting-edge design model in which the cutting edge can be offset along the spherical surface. To improve the accuracy of this model, the twist drill chisel-edge was also introduced into this design model of cutting edge. Then, referring to the toolpath calculation method of complex surface machining, we established a method for grinding the rake face of the ball end mill using a 1A1 standard wheel. For the clearance of the ball end mill, we developed a method to grind the clearance of the ball end mill using an 11V9 standard wheel. Finally, the design model of cutting edge, grinding models of rake face, and clearance were verified by simulations and experiments, respectively. The results show the proposed cutting-edge model has a better profile tolerance. The intersection line between the rake face and clearance coincides with the design’s cutting edge. These prove the effectiveness of methods.

Field tribological tests of two design variants of chisels used in the teeth of a cultivation-sowing unit were carried out in this research. A characteristic feature of the first variant of chisels was the reinforcement of their contact surface and almost the entire rake surface by plates made of cemented carbides. On the other hand, the second variant of chisels was reinforced only in the area of the blade by two plates made of cemented carbides, soldered on the rake face of the elements. The use of the first variant of chisels contributed to a significant reduction in the wear rate of elements, especially in terms of thickness and width loss. Effective reinforcement of the rake face, with relatively lower resistance to length reduction in the elements, raises doubts as to the validity of the use of cemented-carbide plates on almost the entire length of their rake face, because the applied variant of chisels contributed to a significantly higher price. However, the second variant of chisels effectively limited the intensity of the loss of the length of the elements, and the cause of the loss of their usefulness as part of the base material wear. It was found that the main wear mechanism of the cemented-carbide plates consisted of matrix removal under the influence of the finest fraction of the soil, which weakened the embedding of carbides, and then crushing or chipping of carbide grains from the matrix, whereas the dominant wear mechanisms of martensitic steel were grooving and micro-cutting.

Chisel pick is a basic and important rock cutting tool, and the performance of chisel pick directly affects rock mining. In this paper, a rock cutting device was developed for chisel picks cutting experiments. The influence of the depth of cutting, width of chisel pick, rake angle, back clearance angle and tip fillet radius on the cutting performance such as cutting force, normal force, and specific energy has been comprehensively studied. In addition to the general conclusions, the experimental results show that the back clearance angle has an influence range on the cutting, and the ratio of the normal force to the cutting force decreases with the increase of the rake angle; the tip fillet radius greatly improve the mean cutting force and specific energy. The experimental results will provide data support for the design of chisel picks on rock excavation machinery and a more reasonable chisel pick cutting rock mechanics model.

A field experiment was performed in Southwest Germany to examine the effects of long-term reduced tillage (2000–2012). Tillage treatments were deep moldboard plow: DP, 25 cm; double-layer plow; DLP, 15 + 10 cm, shallow moldboard plow: SP, 15 cm and chisel plow: CP, 15 cm, each of them with or without preceding stubble tillage. The mean yields of a typical eight-year crop rotation were 22% lower with CP compared to DP, and 3% lower with SP and DLP. Stubble tillage increased yields by 11% across all treatments. Soil nutrients were high with all tillage strategies and amounted for 34–57 mg kg−1 P and 48–113 mg kg−1 K (0–60 cm soil depth). Humus budgets showed a high carbon input via crops but this was not reflected in the actual Corg content of the soil. Corg decreased as soil depth increased from 13.7 g kg−1 (0–20 cm) to 4.3 g kg−1 (40–60 cm) across all treatments. After 12 years of experiment, SP and CP resulted in significantly higher Corg content in 0–20 cm soil depth, compared to DP and DLP. Stubble tillage had no significant effect on Corg. Stubble tillage combined with reduced primary tillage can sustain yield levels without compromising beneficial effects from reduced tillage on Corg and available nutrient content.

The article concerns developing and implementing the technological principles for manufacturing the working bodies of chisel tools by casting grey cast iron with partial chilling of its working edges and surfaces interacting with the soil layer. High wear resistance of the working body is achieved by chilling its working part by means of a chill inserted into the mold, or by absence of coating in the corresponding zone of the mold. Severe overcooling of liquid cast iron contacting the chill or the metal surface of the mold causes crystallization of the meta-stable eutectics, and in the chilled part it acquires a ledeburite structure, the hardness being not lower than 64 HRC. At the same time, the bulk of the cast iron crystallizes in the stable system, forming austenitic-graphite eutectics and after complete cooling, it should have a pearlitic metal base, ensuring good machine ability of casting by cutting. Working surfaces and cutting edges of chisels are exposed to abrasive and chemical impacts of the soil, causing intense wear, the latter being the main reason for their failure. The utilization of the given technology will allow increasing service-life of the working bodies and improve the manufacturability, according to the criteria for labor intensity and casting mold making.

Aramid fiber–reinforced plastic (AFRP) composites have been widely used in automotive, aerospace, and defense industries. The common AFRP drilling process tends to cause damage to the composite structures which subsequently affects their fatigue lives and in-service performance. Understanding the mechanism of cutting force generation is crucial in controlling the cutting process for achieving desired hole quality and machining accuracy. This study proposes a novel mechanistic model considering both the cutting action and the extrusion action of the chisel edge. For the first time, the extrusion force generated by the chisel edge has been considered as a rigid wedge penetrating into an elastic half space based on the Hertz contact theory. The total thrust force in AFRP drilling is divided into three components: (i) thrust force generated by the cutting lips, (ii) thrust force generated by the chisel edge cutting action, and (iii) extrusion force generated by the chisel edge extrusion action. The proposed model was then validated by experiments and data was compared with the case where extrusion was not considered. The results show that our novel mechanistic model can provide a more accurate thrust force prediction. The average error of our model was 2.54% against the experimental data, whereas the error seen in conventional model without accounting extrusion was 8.22%. This suggests that the chisel edge extrusion plays a significant part in the drilling of AFRP and hence confirms the necessity of considering extrusion in establishing the associated mechanistic model.

The aridization of the climate negatively affects the growth and development of plants and their productivity. The aim of this study was to determine the effect of heat stress and water availability on maize for silage under aridization and to find out the effectiveness of technological methods to maximize the use of available moisture. A long-term multifactorial experiment was performed during the period 1991–2020 in the region south of Rostov, Russia. The long-term multifactorial experiment is located in a zone of high heat supply and insufficient moisture, so the latter factor limits the yield of corn and dictates the need to find solutions to increase its environmental sustainability in extreme weather conditions. The values of the hydrothermal coefficient (HTC) were determined for the period of maize cultivation for each year of the study, ranked in ascending order and grouped into clusters. The results were mathematically processed by calculating the mean values (M) and their standard deviations (±SEM) with Statistica 13.3 software. The optimum conditions for silage maize development were found under the combination of 265 mm of rainfall and a 19.8 °C average temperature during the growing season. The maximum yield of silage maize was 33.8–45.2 t ha−1. In dry years (HTC = 0.3), tillage had an advantage: the yield increase was 0.2–1.6 t ha−1. In wet years, moldboard tillage was preferable: the yield increase was 0.3–2.9 t ha−1. The application of farmyard manure for fertilization increased the yield by 10.5–41.9%. Increasing the fertilizer rate by 1.5 times increased the yield by 21.0–59.8%. In drought, tillage and average fertilizer rate provided returns by increasing yields up to 7.7 kg/kg. Our study provides valuable recommendations in fodder production, promotes moisture conservation, preserves soil fertility on the slopes when cultivating corn for silage, and will be useful to specialists in improving the efficiency of agricultural production.