Rotary Unit Research Articles

Analysis of Vibration Characteristics of Tractor–Rotary Cultivator Combination Based on Time Domain and Frequency Domain

A good planting bed is a prerequisite for improving planting quality, while complex ground excitation often leads to machine bouncing and operation vibration, which then affects the operation effect. In order to improve the quality of rotary tillage operations, it is necessary to study the effects of various vibration excitations on the unit during tractor rotary tillage operations and analyze the vibration interaction relationship among the tractor, the three-point suspension mechanism, and the rotary tiller. For this purpose, multiple three-way acceleration sensors were installed at different positions on the rotary tiller unit of a Lexing LS1004 tractor(Lexing Agricultural Equipment Co. Ltd., Qingdao, China) to collect vibration data at different operating speeds and conduct vibration characteristic analysis between different components. The test results showed that when the unit moved forward at 2.1 km/h, 3.6 km/h, and 4.5 km/h, respectively, the vibration acceleration of the tractor, the three-point suspension mechanism, and the rotary tiller increased with the increase in speed, and there was indeed interaction between them. The vertical acceleration change during the test in the three-point suspension mechanism was the most significant (5.914 m/s2) and was related to the increase in the speed of the vehicle and the vibration transfer of the rotary tiller. Meanwhile, the vertical vibration acceleration of the tractor’s symmetrical structure was not similar, suggesting the existence of structural assembly problems. From the perspective of frequency domain analysis, the resonant frequency at the cab of the tractor was reduced in a vertical vibration environment, with relatively low frequencies (0~80 Hz) and small magnitudes, which might be beneficial to the driver’s health. The rotary tillage group resonated around 350 Hz, and this characteristic can be used to appropriately increase the vibration of the rotary tiller to reduce resistance. The tractor cab resonated around 280 Hz, which must be avoided during field operations to ensure driver health and reduce machine wear. The research results can provide a reference for reducing vibration and resistance during tractor rotary tillage operations, as well as optimizing and improving the structure of rotary tillers and tractors.

A wind-driven rotating micro-hybrid nanogenerator for powering environmental monitoring devices based on a brush-type triboelectric unit

Abstract The rapid rise of the IoT (Internet of Things) technology and microelectronics technology has promoted the development of sensors to ultra-low power consumption. However, for conventional wired power supply and chemical battery power supply, there are difficulties in wiring, inconvenient battery replacement and environmental pollution problems, so there is an urgent need for a green power supply. The low cost and simple structure of TENG (Triboelectric nanogenerator) have attracted much attention from researchers. However, for most of the existing TENG, there are some problems such as narrow operating frequency range, short life of TENG, insufficient traditional flexible friction contact, and serious wear of rigid friction contact. Herein, we propose a rotary brush-type triboelectric-electromagnetic hybrid nanogenerator. Through the experimental tests, the TENG part can output the maximum power of 0.88 mW under the external load of 8 MΩ at 400 rpm (wind speed of about 8.3 m/s). The EMG (Electromagnetic Generator) part can output the maximum power of 15.5 mW under external load of 360 Ω. The LED lighting test proves that the generator broadens the frequency of energy harvesting. In the capacitor charging test, the high voltage characteristics of tribological power generation play the advantages of continuous voltage boost, and the high current characteristics of electromagnetic power generation play the advantages of high power. The hybrid nanogenerator can realize the wind energy harvesting under the broadband wind speed of 3 m/s~14 m/s. At a wind speed of 5.6 m/s, the hybrid nanogenerator ran at about 225 rpm and successfully powered the anemometer after 21 s. After 80,000 cycles, the maximum open circuit voltage only drops by 5.6%, which proves that the rotary TENG unit has a long generation life, and can realize the harvesting of wind energy and the power supply of wind speed sensor.

Analysis Of Work Accident Risk In Plywood Production Units Using Job Safety Analysis Method At Pt Intracawood Manufacturing Tarakan City

Background: The plywood industry cannot be separated from work accidents, so efforts are needed to reduce the number of work accidents by carrying out work accident control programs, namely by implementing risk management. Therefore, this study aims to analyze the risk of work accidents in the plywood production unit using the Job Safety Analysis method. Methods: This research is a Mixed Methods research with the research method used is the Sequential Explanatory Design method. Quantitative sampling was carried out by means of probability sampling with 175 respondents and qualitative sampling by taking 5 informants. The research instruments used interview sheets, Job Safety Analysis Worksheets and AS/NZS 4360:2004 as well as questionnaires and observation sheets. Quantitative data analysis using the Semi-Quantitative analysis method using the Job Safety Analysis Worksheet, qualitative data analysis using content analysis with source and method triangulation. Results: The results of the study found that the hazards in the plywood production process included the work environment, the smell of glue and putty paint, the dangers of working tools such as machines. Based on the identification of potential hazards, a risk analysis is carried out on the rotary work unit, there are 2 work steps with a substantial risk level and 6 work steps with a priority 3 risk level. 1 work step with a risk level of the Priority 3 category and 3 work steps with an Acceptable category risk level. Conclusion: There are several work accidents that are caused by the workers themselves and the work environment. so that control recommendations are given such as making SOPs, providing PPE, conducting training for each work step and providing signs or installing safety signs in places that might cause accidents.

Eulerian CFD simulation of biomass thermal conversion in an indirect slow pyrolysis rotary kiln unit to produce biochar from recycled waste wood

Producing energy and higher value bio-products from waste wood recycled from construction and demolition (C&D) debris has been proposed as an economically viable opportunity in the biomass and bioenergy sectors. However, several challenges associated with the thermal conversion processes remain to be solved. This study introduces a 3D numerical simulation to study thermal conversion of wood chips. Combined biomass combustor, and indirect pyrolysis unit is used to create a self-sustainable biomass unit which does not rely on fossil fuel. Multizone heat distribution in the rotary kiln unit is investigated by employing CFD, an analytical algorithm and measurement tools in different zones of the equipment. A multizone heat transfer concept, the overall yield rate of biochar, thermochemical conversion of the bed, the volume shrinkage in the wood chips during the pyrolysis process, as well as biomass volatile and tar composition, and finally the potential of energy savings is widely investigated. CFD results and experimental evidence confirm that at least 31 % energy saving in drying zone can be achievable if drying and pyrolysis zone are separated in the indirect slow pyrolysis rotary kiln unit. The quality of biochar improved by 21 % increase in fixed carbon content and tar condensation is controlled.

Влияние регенерации слоистого модификатора трения на триботехнические свойства смазочных композиций

The paper examines an influence of the regeneration efficiency of the developed anti-wear additive on tribological properties of the lubricating composition, including a lubricating oil and the additive. The anti-wear additive was a layered friction modifier – molybdenum diselenide MoSe2, mixed in the volume of a composition of unsaturated fatty acids – stearic acid and oleic acid. Lubricating oil M-16G2TSS was chosen as the base lubricant, with respect to which the tribological properties of other lubricants submitted for testing are compared. For all cycles of tests, a volume of no more than 25 cm3 of lubricant was used to avoid high thermal inertia when the test samples moved on the friction machine. Experiments of the regeneration of the additive were carried out on a rotary mixing unit of the author's design, and the solution has a long storage period of 8 640 hours (about 12 calendar months). The possibility of restoring the uniform distribution of molybdenum diselenide throughout the volume of the additive in a suspended state has been revealed. This lubricant composition, after restoration of the structure by stirring, can be used in the production of a lubricant composition based on M-16G2TSS oil. Using a reciprocating friction unit of a friction machine, simulating the cylinder-piston group of a marine diesel engine, the resulting lubricant composition was compared with other lubricants based on molybdenum diselenide, the additive solutions of which have different storage periods before being added to the lubricating oil, as well as with the base lubricating oil. The assessment of the tribological properties of lubricants based on M-16G2TSS oil by determining the weight wear and further using this value to estimate the resource of the friction unit has been made. Rotational regeneration has shown satisfactory effectiveness in partially restoring of the tribological properties of a lubricant composition with the participation of an additive, but is not enough effective compared to rotational pulsation mixing of the additive in order to create perspective lubricant compositions.

Development of an accelerator-based neutron source to prototype Mo-99 production, Part II: A liquid LBE loop under a high vacuum

To provide US domestic supply of Mo-99 without using high-enriched uranium (HEU), a subcritical uranium target assembly (UTA) is irradiated by an accelerator-based neutron source to create Mo-99 through fission. Part I of this work discusses the design of a liquid lead–bismuth eutectic (LBE) windowless target for an accelerator-based neutron source development. Part II discusses how to couple this windowless target to an accelerator operating at an ultra-high vacuum and the subcritical UTA cooled by water at room temperature.Due to the windowless design of the target, the liquid LBE flow shares an ultra-high vacuum (<1.3 × 10−7 Pa or 10−9 Torr) space with the accelerator. As a result of this shared vacuum space, the LBE system must operate at a high vacuum (10−3 ∼ 10−6 Pa or 10−5 ∼ 10−8 Torr). A magnetic rotary motion feedthrough unit utilizes magnetic fluid to allow rotation of the pump while maintaining a high vacuum environment. Prior to testing the LBE system under vacuum, a pump curve measurement is performed to estimate flowrate in the system. This measurement also generates data on orifice loss coefficients, which are compared to correlations in literature. The second experiment investigates vacuum level in the LBE system during operation. High vacuum is maintained (10−3 ∼ 10−5 Pa or 10−5 ∼ 10−7 Torr) during system operation, and a residual gas analyzer (RGA) scan shows that partial pressures of residual gases in the LBE system lower over the duration of LBE system operations. The third experiment investigates the gravity driven liquid LBE flowing out of the target chamber in the return line, which is partially full. If the liquid LBE is not drained quickly enough, flooding in the target chamber could occur. The coefficient n in the Manning equation is found to be around 0.008 s/m1/3. The last experiment performed is a demonstration that a vacuum jacket could provide sufficient thermal insulation to allow coupling between 300 °C LBE loop and a water tank at room temperature. The results from these experiments have influenced the development of the neutron source for the future commercial scale Mo-99 production system.

Assessment of the Efficiency of Wastewater Treatment Plant in Oil and Gas Firm in Eleme Rivers State, Nigeria

The study aimed to determine the efficiency of a wastewater treatment plant and the quality of effluent discharged by the plant into the receiving water body (Okochiri River) in Eleme, Rivers State. The study lasted for four months. Wastewater samples were collected at various stages of the treatment unit and tested for major water quality parameter such as Biological Oxygen Demand (BOD), oil/grease, phenol, Dissolved Oxygen (DO), Total Suspended Solids (TSS), and sulphide. In general, the composite wastewater treatment system (comprising dissolve air floatation, Rotary Bio-Disk, and sedimentation unit) was effective in pollutant removal, except for sulphide, which had a negative efficiency (-238%). In line with Pearson Correlation, there are strong positive relationships between several parameters, such as pH and Sulphide (0.93), Phenol and Oil/grease (1.00), and Phosphate and Sulphide (0.91). The Principal Component Analysis yielded four principal components (PC1-4): PC1 parameters with the highest loadings on the first factor (D1) were sulphates and phenols, whereas Chemical Oxygen Demand and Biological Oxygen Demand had the highest loadings on the second factor (D2). Dissolved oxygen was most strongly associated with the third factor (D3), and pH was the parameter with the highest loading on the fourth factor (D4). It is recommended that the wastewater treatment system's overall efficiency be improved for the system to consistently meet regulatory limits for pollutant control. Recommendations for improving system efficiency include (1) ensuring regular maintenance of individual units in the treatment plant; and (2) maintaining optimal operating conditions for the rotary bio-disk unit.

Перспективы внедрения новейших технологий на предприятиях АО «Южный центр судостроения и судоремонта»

The article focuses on the trends of development in modern shipbuilding in the context of digital transformation and promising national projects recommended for implementing at the enterprises of Southern Center for Shipbuilding and Ship Repair, JSC. The calculation program of shipyards, the composition and main features of the created industries are given. There is described the modern Russian technological equipment recommended for implementation at Southern Center of Shipbuilding and Ship Repair, JSC including machines with numerical control for laser and plasma cutting the sheet parts and multifunctional bending and straightening machines with a rotational-local deformation principle. Pictures of machines for thermal cutting of sheet parts with digital control of the Ritm-M and Ritm-MA-Laser types are presented (plasma and oxygen cutting machine, wide-portal plasma and oxygen cutting machine with a rotary unit for cutting edges for welding, laser cutting machine) developments of Center for of Shipbuilding and Ship Repair Technologies, JSC implemented at the branch Astrakhan Shipyard of Zvezdochka, JSC. Pictures of multifunctional bending and straightening machines of the MGPS-25 and MGPS-100 types developed by the Center for Shipbuilding and Ship Repair Technologies JSC implemented at the Astrakhan Ship Repair Plant branch of Zvezdochka, JSC, are presented. The comprehensive introduction of the latest technologies and principles of production organization at the enterprises of Southern Center for Shipbuilding and Ship Repair, JSC will reduce the labor intensity of building the ships of the calculation program by more than 2 times.

Sliding Mode Control for a Non Linear 2 DoF Torsion System

2 Degree of Freedom(DoF) torsion system can be used to demonstrate the torsional dynamics and the effect of flexible coupling between the actuator and the load encountered in real world control applications. In this work non linear dynamics of a 2 DoF torsion system is considered and Sliding Mode Controller(SMC) is designed for controlling the angular position of the rotational load of the system. The plant consists of a rotary servo-base unit which includes a DC servomotor in a cubic solid aluminium frame to which the gear train is attached. Its horizontal shaft will rotate the flexible coupling attached to the rotational load. Multiple torsional loads can be attached to the rotary servo-base unit. In this work, two torsional loads are attached to the rotary base unit and hence called 2 DoF torsion system. The angular position of the flexible load is to be controlled by applying the control voltage to armature of the DC servomotor in order to produce the required torque. Effectiveness of the controller has been achieved from the simulation result.

Manufacturing a Model for Moving the Electrode of TIG Welding for the Rib Piper Connection

This paper provides a complete overview of the entire process of designing a welding head moving device and its implementation as a semi-automatic welding machine. The mechanical structure of the device is designed based on the size of the material pipe and the accompanying technical requirements. The system is equipped with an arc generator set and a rotary speed control unit allowing its use as an orbital welder.

ПОВЫШЕНИЕ КАЧЕСТВА ТЕХНОЛОГИЧЕСКОГО ПРОЦЕССА ПРИ РЕКОНСТРУКЦИИ АВТОМОБИЛЬНЫХ ДОРОГ

As a result of the study, it was found that the type and structure of the material used has a great influence on the quality of the road surface; in this light, special attention is paid to the crushed materials. In this regard, within the framework of the article, several materials for grinding in a rotary centrifugal unit are considered. Selected various working bodies of the unit, affecting the technological parameters of the grinder. The most rational chopper components are installed, con-venient for further use in production.

A Novel Gripper with Integrated Rotary Unit and Force Control for Pick and Place Applications

Modern electrical grippers have lower life-cycle costs compared to pneumatic ones. Furthermore, they provide force control, making it possible to grasp objects with different fragility using a single device. At the same time, electrical grippers have a higher end-effector weight, installed on the robot’s flange and lower closing speed, preventing them from replacing pneumatic solutions in high dynamic Pick and Place applications. This research faces both issues by synthesizing a novel gripper mechanism based on a Torque Distribution Gearbox, which makes it possible to relocate the electric motors to the static frame of a delta robot. The proposed gripper not only has a lower mass and a higher closing speed than competitive electric solutions, but it also provides unlimited rotation around the vertical axis. The performance of the gripper was tested in experimental studies, which showed that a created aluminum prototype provides a precise force control in the range from 3 N to 48 N with an accuracy not worse than 1.27 N. Moreover, its finger’s speed is 3.1–56 times higher than market available electrical grippers, which makes it comparable by this parameter with pneumatic solutions used in high dynamic Pick and Place applications.

Laboratory Investigations on Cutting Torque and Efficiency for Topping of Onion Leaves Using Wire-Type Rotary Unit

Laboratory Investigations on Cutting Torque and Efficiency for Topping of Onion Leaves Using Wire-Type Rotary Unit

Design and Fabrication of a Millimeter-Scale Rotary Actuator based on the Twisted Shape Memory Alloy (SMA) Wires

Shape memory alloy (SMA) has been widely used for many engineering and scientific applications, because it is largely deformable with high power density, and can be actuated easily by resistive heating. It is possible to reduce the size of the actuators by integrating or embedding SMA into the structures. While many applications have been reported regarding linear or bending actuators using the SMA wire, the development of a rotary actuator remains important and challenging for the engineering applications. Here, a new type of millimeter-scale rotary actuator is proposed based on the twisted SMA wires. SMA wires are twisted, folded, and integrated into the rotary actuator, and simple change of the twist direction enables the rotary actuator to rotate in the opposite direction. By integrating the oppositely twisted SMA wires into one rotary actuator unit, bidirectional rotary motions are possible. The actuation mechanism, design, and fabrication processes of the proposed rotary actuator are presented and demonstrated with its actuation performance. The fabricated actuators had average rotary working ranges from -38.68±4.92 deg to +45.37±8.79 deg in counterclockwise (CCW) and clockwise (CW) directions. This study will leverage the practical advances in the relevant engineering and scientific applications.

Optimization of Permanent Magnet Parameters in Axial Flux Rotary Converter for HEV Drive

This paper focuses on the development and optimization of a special hybrid electric vehicle arrangement known as a four-quadrant rotary converter. The introduction summarizes the main advantages and disadvantages of existing topologies in radial and axial flux arrangements. Based on previous experience, we developed a novel axial flux arrangement that eliminates the problems and disadvantages associated with existing radial flux solutions. In addition, this paper evaluates and subsequently describes the optimization of permanent magnet parameters in an axial flux rotary converter unit. A number of 3D finite element method optimizations were performed to find the optimal mass distribution of permanent magnets on the frontal area of the outer rotor in the axial flux rotary converter unit. The optimization involved the permanent magnets’ material, shape, and thickness in order to achieve maximal efficiency of the entire unit while leaving its nominal output power and speed unaffected. The results show an increase in the overall theoretical efficiency of the outer rotor unit from 90.2% to 94.4% following the optimization.

Algorithm for calculating the power factor of a rotary mixer drive

The purpose of the research was to develop a methodology for calculating the power factor of the rotary agitator unit drive with its components and an algorithm for their determination, implemented in the form of a computer program. The structural scheme of the bulk material mixer with the developed agitator unit is given. The definition of the required parameters is realized on the base of the known expressions and operating parameters of the mixer. The developed technique and calculation algorithm, which is realized in the MathCAD mathematical package, allow determining the peripheral velocity profile parameter of the material and the hydraulic resistance coefficient of the working body, the power factor and the mixing capacity factor, which allows calculating the torque and power required for material mixing by a rotary mixer with a vertical shaft of the developed design.

Increase in grain combine harvester performance and in quality of harvesting grain crops

Based on the analysis of the results of combine harvester production tests and the long-term studies, carried out by the authors, the directions for increase in combine harvester productivity and in grain crop harvesting quality, are proposed. In three blocks of directions for increasing the combine harvester efficiency, a new direction of completing multifunctional harvesting units, joining together grain harvesting with simultaneous performance of one of the accompanying operations (stubble plowing, straw pressing, sowing catch crops, etc.), is found. The acquisition of multifunctional harvesting units is based on self-propelled, all-wheel-drive harvesters, trailed and mounted on a power unit such as “Palesse” (Belarus). The original unit can be completed on the basis of a “Penha” pull-type combine (Brazil). Among other directions of combine efficiency increasing, the observance of the rhythm and flow of the working process is substantiated, the attention is paid to the complex performance of the harvesting period. Attention is also paid to the obligatory coordination of the relationship between combine parameters and harvesting conditions: field size, crop yield, combine nominal performance, working speed, header cutting width. The following is an example of the effective operation of a rotary combine harvester in comparison with a beater-drum one and its significant influence on the winter wheat grain quality of strong varieties. It has been proved that due to reducing the grain injury by the rotary threshing-separating unit, post-harvest ripening and cleaning on thrashing floor, it is possible to increase the grain quality indicators by one class.

РОЗРОБЛЕННЯ СПЕЦІАЛЬНИХ МАТЕМАТИЧНИХ МОДЕЛЕЙ ДОСЛІДЖЕННЯ ТОЧНОСТІ РЕАЛЬНИХ ПОВЕРХОНЬ ЗУБЧАСТИХ КОЛІС ЦИКЛОЇДАЛЬНИХ ПЕРЕДАЧ

Promising areas for improving robotic systems based on cycloidal gears aimedto increase their accuracy and other performance characteristics. The accuracy of the rotary unit and the mechanism as a whole is determined by errors in the manufacture of the transmission. Integral quantities are not enough to assess the accuracy of the transmission wheels. To determine the errors of the geometry of parts requires a technique that includes modeling of its real surface. The cyclic nature of the curve that defines the generating surface of the wheel allows the use of optimized mathematical models based on Fourier series. The technique allows for accurate processing of experimentaldata and compare them with the theoretical profile. Approbation of the concept requires modeling of the theoretical profile and research of the manufactured parts. The method allows to determine the parameters of the wheels by analyzing the differences between the simulated surface of the part and the theoretical profile. A hole in the part can be used as a base surface in the manufacture. Determination of the surface profile of the transmission wheel is carried out on a coordinate measuring machine, which allows to get a set of points. Surface modeling by discrete values is performed by spline interpolation. In the future, the description of the surface is performed using harmonic functions. The proposed mathematical apparatus allows the use of spectral analysis tools and statistical methods. The harmonic series is obtained by means of the Fourier transform. Monte Carlo methods allow to compare the mathematical model of the real profile of the mechanical transmission wheel and the theoretical surface. This makes it possible to take into account the presence of eccentricity, phase shift and other features of the part when determining the accuracy parameters. The mathematical model allows to effectively use experimental data in determining the characteristics of the surface of the part. The use of stochastic parameters in modeling makes it possible to take into account the accuracy of the wheel and increase the accuracy of determining the parameters of mechanical transmission.

PROBLEMS OF DRIVE MECHANISMS OF TECHNOLOGICAL SECTION OF FIRING AND GRINDING DURING CEMENT PRODUCTION

The analysis of conditions of long operation of driving mechanisms of technological sites of firing and grinding at cement production is carried out in the work. Typical variants of mutual arrangement of crown pair elements in case of rectilinear axis of rotation of technological unit body and axial beating of gear ring, as well as variant of mutual arrangement of crown gear elements in case of curved axis of rotation of rotary unit body are considered. A technique for determining the total angle of skew of the teeth of the crown pair, taking into account the errors of manufacture and the relative position of the wheels of the open gear. On the basis of experimental data the dependences of the total skew angle of the teeth of the crown pair as a function of the rotation angle of the gear crown are constructed and the possible range of the total skew angle under different operating conditions of the considered large rotating units is determined. To assess the stress-strain state of the elements of the ring gear mounted on the furnace body, a solid model was created in the software environment Solid Works Simulation. As an example, the dependences of the change in the magnitude of the deformation of the teeth of the toothed crown in the plane of action of a uniformly distributed normal force are determined. Practical recommendations for improving the design of the crown gear pair are offered. Keywords: rotary kilns; mills; crown gear; toothed crown; the angle of skew of the teeth; finite element method

Transformation of Biodegradable Organic Municipal Solid Waste to Compost Using Stationary and Rotary Units

This study aims to convert the municipal solid waste (MSW), which include garbage and chicken manure as raw biodegradable organic waste to produce a compost in order to transform these materials into recommended fertilizer. The principle of aerobic composting method is a waste oxidation through holding these mixed raw materials with a ratio of 1:1 garbage and chicken manure in two units of composting, rotary unit and stationary unit with recommended Carbon/Nitrogen ratio C/N of 20:1 and pH of 6.5 with moisture content of about 40% by adding water during composting process and presence of oxygen naturally. The period time of composting process was 69 days to get normal temperature of compost bulk equal to ambient temperature and pH value as natural value using two composting units. The composting results during first 30 days shows the temperature values 59.5 and 55oC for rotary unit and stationary units that refers to microbial action of microorganism and decomposition of organic matter to energy as heat. The pH values were having acidic state during first week that refers to the formation of organic acids. The final compost characteristics show a C/N ratio of 20.8 and 22.275 for rotary and stationary units, respectively with a decrease in C% and N%, which refers to a successful composting process, where Nitrogen, Phosphor and Potassium NPK values were (1.428:1.719:4.508) % for rotary unit and (1.361:0.419:3.884) % for stationary unit and electrical conductivity of 5.5 and 6.04 mS/cm as acceptable value according to the recommended standard values.