International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

A comparative analysis of wear performance of coated harrow discs by plasma-jet thermal deposition was evaluated under agricultural conditions to assess the performance of atmospheric plasma spraying systems. This paper presents a long-term comparative field evaluation under identical operating conditions on a quartz-rich argic luvisol soil. Disc wear was quantified by periodic measurements of mass loss and diameter of the studied discs.
The uncoated disc showed the most severe degradation, with a total mass loss of approximately 700 g and a rapid acceleration of wear after the first 5-10 ha of harrowing. The results obtained under field conditions demonstrate that the microstructural integrity of the coating is more critical than the nominal hardness and highlight the superior effectiveness of APS ceramic coatings for extending disc life in abrasive agricultural soils.

The results of tribological tests of the active area of harrow disks with coatings obtained by the plasma spay thermal method are presented. This study is based on scanning electron microscopy of coated harrow disc samples undergoing standard tribological tests that focuses on the mechanical properties of coatings using tribological methodology. Tribological studies were conducted to determine the following main parameters of the harrow disc material such as: adhesion to the substrate, coefficient of friction, Young’s modulus, stiffness and hardness of coated samples and the base material. As the result, improving the mechanical and chemical properties of materials used to manufacture the working bodies of coated harrow discs allows for increased resistance to abrasive wear in modern agricultural machinery.

This study presents a comparative analysis of three types of coatings taken from the active area of the coted harrow disks using atmospheric plasma spray deposition method (APS). The resulting coatings increase the durability of the harrow discs and the inclusion in the componence of coatings of carbides and powdered ceramic compounds will enhance the mechanical characteristics. This study focused on scanning electron microscopy of the coated samples from the harrow discs and their tribological properties. SEM imaging and EDS analysis have been carried out to clarify the morphological characteristics and study of disc cross-section. Tribological tests were carried out to determine the following main parameters: adhesion to the substrate, coefficient of friction (COF), modulus of elasticity and hardness of the material.
The development and implementation of modern technologies for improving the mechanical and chemical properties of materials for
coated harrow discs will increase resistance to abrasive wear in modern agricultural conditions.

The presented research results concern the amount of work and energy incurred in the grain production technology and the aspect of the quality of separating grain from the cob cores. The dynamic increase in the area of sweet corn cultivation for processing purposes (canning, freezing) affects the fact that manual harvesting is increasingly being replaced by combine harvesting. It ensures higher and energy-efficient work efficiency, as well as harvesting at the optimal stage of ripeness, which is particularly important in the case of sweet corn. Sweet corn cobs of the Candle variety were harvested with a Bourgoin combine harvester at the stage of late-milk maturity, and then subjected to processing consisting in de-shirting and cutting off the grain The quality requirements of the separated grain are, m.in: smooth surface and equal length of the cut grains, no mechanical damage and low losses of weight and nutrients. The quality of the separated (cut) grain was analyzed by measuring the length and surface condition of the cut grain. Grain with weight losses was classified as grain of inferior quality. The grains were cut off on a cutter for variables ranging from 167.5 to 301.2 rad/s angular velocity of the knife head and constant linear speed of the cob feeder 0.31 m/s. For comparison purposes, grain is divided into three classes. The workload incurred for the combine cob harvesting was the highest for post-harvest processing of cobs – 31% and soil cultivation – 27%, and energy expenditures for soil cultivation – 341 kWh/ha and for combine harvesting – 285 kWh/ha. The length of the cut grain increased by 26% in class I, and decreased by 14% in class II and by 11% in class III. On the other hand, the share of grain of inferior quality decreased in class I by 5%, in class II by 7% and in class II by 3%.

The stages of the life cycle of complex technical products, such as tractors and self-propelled agricultural machinery, are examined. The need to correct /extend/ the period between repairs of individual aggregates and nodes is justified.
For this purpose, a corrective expression was derived for determining the economically expedient extension of the between-repair period of the machine elements, which takes into account the economic effect of extending the repair period, the relative share of the costs of purchasing replacement units and the set value of the confidence probability of the resource of the aggregates.

The article proposes a classification based on the method of movement of the working parts of the planting apparatus, which identifies three groups of transplanting machines: with the movement of the working parts in a vertical plane, a horizontal plane, and a combined method. The speed of planting seedlings depends on the following main factors: the frequency m of seedling supply, the planting step l, the design of the planting apparatus with seedling holders, the condition of the planting material, as well as the experience and skill of the planting operators. Feeding seedlings into seedling holders or cups of the planting apparatus is limited by the physical capabilities of a person, namely the number of seedlings fed per minute or frequency m. Thus, in order to increase the speed Vm of seedling planting, it is necessary to increase the frequency m of seedling supply. The speed of planting seedlings into cups or seedling holders (the frequency m) actually determines the maximum operating speed of the transplanting machine.
The study of the technological process of operation of a transplanting machine, as well as a phase analysis of the working process of a carousel-type transplanting machine, makes it possible to better understand ways to improve the design of the machine and its working parts and will make it possible to obtain important decisions on increasing the speed. As a result of a theoretical study of the technological process of a carousel-type transplanting machine, a relationship was obtained between various factors on which the maximum operating speed of planting seedlings depends.

The article identifies the main current problems of walnut cultivation technology and analyzes of existing technologies and machines for harvesting fruits, including nut crops.
As a result of the research, the main directions for improving the technology of growing walnuts by improving the technological and technical parameters of the design of machines and equipment for harvesting walnuts were proposed and hypotheses were put forward for their improvement, in particular, a machine equipped with a bar for shaking fruits and a catcher, which is designed to collect fruits and partial destruction of the green pericarp of the walnut fruit.

The main disadvantages of transplanting machine are presented in the article and the mathematical modeling of the operating system of the carousel type transplanting machine with a new method of calculation of the design parameters of the system is proposed. As a result of theoretical research of the operating system of carousel type transplanting machine the rule of motion of the point F and the mathematical model for determining initial velocity V0 of the falling seedling have been obtained.