Milling Head Research Articles

Appropriate Stubble Height Can Effectively Improve the Rice Quality of Ratoon Rice.

Ratoon rice, the cultivation of a second crop from the stubble after the main harvest, is recognized as an eco-friendly and resource-saving method for rice production. Here, a field experiment was carried out in the Yangtze River region to investigate the impact of varying stubble heights on the grain quality of ratoon rice, as well as to compare the grain quality between the main and ratoon season. This study, which focused on 12 commonly cultivated rice varieties, conducted a comprehensive analysis assessing milling characteristics, appearance, and cooking quality. The results show that ratoon rice crops exhibited a higher milled rice rate and head rice rate compared to the main rice crops. Conversely, chalky rice percentage, chalkiness degree, and amylose content were lower in ratoon rice crops. Principal component analysis grouped eight relevant quality indicators of rice quality which were concentrated into three categories, with amylose content identified as the key indicator of rice quality for distinguishing between different stubble heights. Random forest results reveal a robust and significant correlation between appearance quality index and amylose content. Subordinate function analysis indicated that a stubble height of 30 cm resulted in optimal rice quality, with Lingliangyou 211 exhibiting the highest quality and Xiangzao Xian 32 the lowest. Overall, our study suggests that ratoon rice crops generally outperform main rice crops in terms of quality, with the optimal measurement at a stubble height of 30 cm. This study holds substantial importance for selecting appropriate stubble heights for ratoon rice crops and enhancing overall rice quality.

Drying and Tempering Influence on the Milling Quality of Parboiled Rice

Rice occurrence and dealings are features of the tradition of Bangladesh’s populace. However, their experience of parboiled paddy for domestic consumption is limited. Proper drying and tempering are very important for maximum milling output. The study was conducted to investigate the drying and tempering influence on the milling quality of parboiled paddy. The sample size of the paddy was 36 kg as per treatment. In the case of T1 (daily 4 hours sun drying) and T2 (daily 5 hours sun drying), 1-hour drying and 1/2 hour tempering were maintained, and for T3 (daily 4 hours sun drying) and T4 (daily 5 hours sun drying), 1-hour drying, and 1-hour tempering were maintained. The temperature of the paddy sample was varied from 18 °C to 42 °C in five treatments. Drying over three days at different time intervals led to reduced moisture content (from 23.42% to 9.24%), resulting in increased kernel hardness for reduced breakage during milling. The highest kernel strength after three days of drying was found to be 50.65 N/m for T4. The relative humidity, day temperature, air flow velocity, and solar radiation varied from 48% to 78%, 24 °C to 29 °C, 0.00 to 0.70 m/s, and 64450 to 108100 lux, respectively. Based on milled rice, the best milling output and head rice recovery were found to be 20.51 kg and 19.80 kg, respectively, for T4. The lowest quantity of broken rice was 0.50 kg found for T1 and T4, respectively. The lowest quantity of loss was 1.10 kg for T2, and the lowest quantity of husk and bran was 6.88 kg for T4. Results showed that among the five treatments, 5 hours of sun drying daily, maintaining the procedure of 1-hour drying and 1-hour tempering until the moisture content is reduced to 10% (T4), is more effective for increasing milling recovery.

Assessment of the Correlation between the Monitored Operating Parameters and Bearing Life in the Milling Head of a CNC Computer Numerical Control Machining Center

The present paper describes a study conducted at the request of the operator of machining center equipment. The operator observed undesirable indicators in terms of increased backlash and vibration of the milling head and poor quality of the machined surfaces. Vibration measurements and vibrodiagnostics were carried out before disassembling the milling head in the idle state. The bearings, lubricant, and friction regime were analyzed in the next step. The vibrodiagnostic methods used included VEL, ACC, EN2, EN3, and EN4, with recommended limits conforming to STN ISO 10816-3. The vibration values obtained indicated a problem with the bearings, exceeding the limit values. After disassembly of the bearings, abrasive wear, corrosion, and improper lubricant conditions were detected. Lubricant analysis showed the presence of abrasive and corrosive particles, indicating an unsatisfactory friction regime. Determining the optimum lubricant temperature and the effect on friction torque constituted other aspects of the study. Inspection of the bearing microgeometry confirmed unsatisfactory roundness. Furthermore, the assembly of tapered roller bearings with axial preload was analyzed with a focus on bearing stiffness, accuracy, and life. The results showed that preload improves shaft guidance accuracy and load distribution, promoting reliable operation and extending bearing life.

Metabolomics Analysis of Variation in Grain Quality of High-Quality Japonica Rice

In recent years, the semi-glutinous japonica rice variety has been extensively utilized in Jiangsu Province to greatly increase rice quality. Nevertheless, the increasing occurrence of seed variation presented a major threat to rice quality. Enhancing the quality of rice grains has emerged as a critical factor in guaranteeing consumer acceptance. Throughout this investigation, five lines (VJ1, VJ2, VJ3, VJ4, and VJ5) selected from the Nanjing9108 population in Liyang were used as research materials, and original cultivars of Nanjing9108 (CKJ1) provided by the original breeder were utilized as control materials to compare rice quality and differential metabolites. VJ4 and VJ3 demonstrated a significant reduction in milled rice rate and head milled rice rate when contrasted to CKJ1. Compared with CKJ1, the amylose content of the five strains was significantly increased. Only VJ3 amplified the 106 bp target band, and its 2-AP content was 0 ng/g. Most metabolites are mainly enriched in cutin, suberine, wax biosynthesis, histidine, and tryptophan metabolism. The primary metabolites throughout the metabolic pathway involve lipids and lipid-like molecules (mono palmitin, alpha-eleostearic, and palmitic acid) and amino acid metabolites (L-glutamate, L-tryptophan, and L-serine). The identification of these key metabolites helps in the discovery of prospective biomarkers for screening seed variation throughout seed production.

AISI 304 stainless steel milling process state diagnosing

The article presents the results of works on the analysis of using cutting forces and torque to determine AISI 304 stainless steel milling process state. The research and analyzes were carried out for the determine tool state and the process state itself. The tests were performed using Sandvik milling head, equipped with 345R-1305M-PM 4230 inserts . This study presents and discusses the obtained results determining the resultant value of the minimum and maximum cutting forces and the tool life. The results of observations of the tool's condition were presented.

Effect of the drag-finishing of cutting blades made of sintered carbides on tool life in particleboard machining

ABSTRACT It is currently known that in certain circumstances pre-rounding of cutting blades can significantly increase tool life. Despite many data on the beneficial effect of drag-finishing on the durability of metalworking tools, it is not entirely clear whether similar benefits appear when machining wood-based panels. The results of some pilot study are quite promising but the real impact of cutting blades pre-rounding (it is about blades made of various standard cemented carbides), on tool life in particleboard milling are very rarely studied. The study aims to fill this gap in the knowledge system. The experimental research was carried out using a CNC milling machine equipped with a single-blade milling head with replaceable blades. It turned out that the positive effect of the drag-finishing of cutting blades on tool life in particleboard machining depends on the structure and hardness of carbide. A significant extension of the tool life (about 50%) was observed only in the case of particularly hard carbide (2240 HV10). There was no significant advantage for the softer type of carbide (1800 HV10).

Acoustic determination of the chatter and the cutting tool Planarity fault of an on-site milling

On-site machining is a specific area where harmful vibrations can be generated by the dynamic interaction between the tool and the workpiece. These vibrations often cause the degradation of the workpiece and the cutting tool. It is therefore necessary to suppress and control this phenomenon. In this paper, we present the acoustic characterisation of a common fault in on-site machining that causes these harmful vibrations: the tilting fault of the cutting tool. Our preliminary results show that the presence of microphones allows us to have little spatial control of the cutting tool. There is an increase of around 5 to 8 dBA for a 0 and 0.5 mm tilt of the milling head along the X axis. An increase of around 10 to 12 dBA is recorded for a tilt of 0.10 and 0.20 mm of the milling head along the X axis. In contrast to the X-axis, tilting the milling cutter along the Y-axis only results in a 5 dB increase in noise level for the filtered signals.

FACE MILLING CUTTERS FOR COMPOSITE MILLING HEADS

The paper considers designs of the face milling cutters used in composite milling heads. The advantages and disadvantages of known face milling cutters are analyzed. The design of the face milling cutter, in which the number of additional screws is equal

Characteristics determination for milling working equipment of excavator

Introduction. The long network of pipelines on the territory of our country needs timely and high-quality repairs. The entrenching tool used so far increases the complexity of work on the overhaul of pipelines, which forces to create solutions for mechanizing the process of digging the pipeline. The purpose of the study conducted in this article is to determine the performance and total torque of the working equipment of the excavator. A general view of the working equipment with the designation of the positions necessary for the study is given. Methods and materials. The concept of specific values of torque and power per one cutter of working equipment has been introduced. The dependencies of the total productivity of the cutters and the torque of the cutters are established. Due to the peculiarity of the design of the working equipment, each of the dependencies is considered separately for the front and rear incisors. The surfaces that reflect the influence of the angular velocity of rotation of the milling head and the angle of installation of the cutters on the parameters under the study are constructed. Results. Based on the obtained dependence of the total torque of the milling working equipment, a nomogram was compiled. By setting the number of N cutters, the speed of rotation of n working milling head and the number of strokes of the DorNII (Road Research Institute) striker, it is possible to determine the required torque of the hydraulic motor. Сonclusions. According to the results of the theoretical study of the process of cutting soil with the help of excavator milling working equipment, the dependencies of the total productivity and total torque of the working equipment were established. The constructed graphic dependencies help to determine the degree of influence of design and operating parameters on the work process. The created nomogram is recommended for use in the design of working equipment.

MILLING HEADS FOR MACHINING MUTUALLY PERPENDICULAR FLAT SURFACES

The paper deals with issues and shows the relevance related to the use of composite milling heads for machining wide flat surfaces. A 3D model of a composite milling head is presented. Shown, the design of the composite milling head with four face mills allows the milling of planes in mutually perpendicular directions. The surface machined with a single pass milling is continuous in width. It allows to shorten the cutting length and machining time, increasing productivity wide flat surfaces by milling.

Analysis of Cutting Forces during Machining with Additive-Produced Milling Head

Today's milling cutting tools are produced in various types and shapes for a wide variety of machining processes. Development continues and offers new technological solutions. The design of replaceable milling heads offers a significant cost reduction, as only the worn-out part is replaced instead of the en-tire tool. The tough connection between the tool and the shank achieves stable performance in roughing and finishing milling. Because of the possibility of using different milling inserts, the number of neces-sary tools will also be reduced and the flexibility of using milling tools will increase. The article exam-ines the cutting forces when machining a milling head produced by additive technology and made of Onyx material, which is reinforced with carbon fibre.

Determination of torque for milling working equipment of excavator when repairing a pipeline

Introduction. During the overhaul of the pipeline to remove the soil under the pipe, a trench tool is currently used. The new technology of excavation of soil under the pipeline proposed by the authors, which provides for the use of replaceable milling working equipment for a hydraulic excavator, makes it possible to increase the speed of repair work. The purpose of the article is a theoretical study of the process of interaction between the structural elements of milling equipment and the developed soil.Methods and materials. Based on the basic provisions of the theory of interaction of the working bodies of earthmoving machines with the soil, a mathematical model of the work of the milling working equipment of a hydraulic excavator was created. It makes possible to get the dependence of the resistance forces arising on the cutters of the working equipment, on its design parameters and the physical and mechanical properties of the soil.Results. According to the results of the analysis of the obtained dependence of the torque on the cutting angle and the angular speed of rotation of the milling head, it was found that the greatest influence on the torque required to overcome the forces of soil resistance and the drive of the working body is exerted by the angular speed of rotation of the milling head. The minimum value of the torque in the study area 50 N·m is observed at the point where the cutting angle of the soil is 45º, and the angular speed of rotation of the milling head is 4 rad/sec. The maximum torque 215 N·m was recorded at a cutting angle of 65º and a milling head speed of 10 rad/sec.Сonclusions. According to the results of the theoretical study of the process of cutting soil with the help of the milling working equipment of the excavator, the torque of the hydraulic motor necessary to rotate the milling head was established. The results of the theoretical studies carried out are recommended to be used to calculate the design and operating parameters in the design and creation of an experimental sample of milling working equipment.

Process Development for Batch Production of Micro-Milling Tools Made of Silicon Carbide by Means of the Dry Etching Process

Downsized and complex micro-machining structures have to meet quality requirements concerning geometry and convince through increasing functionality. The development and use of cutting tools in the sub-millimeter range can meet these demands and contribute to the production of intelligent components in biomedical technology, optics or electronics. This article addresses the development of double-edged micro-cutters, which consist of a two-part system of cutter head and shaft. The cutting diameters are between 50 and 200 μm. The silicon carbide cutting heads are manufactured from the solid material using microsystem technology. The substrate used can be structured uniformly via photolithography, which means that 5200 homogeneous micro-milling heads can be produced simultaneously. This novel batch approach represents a contrast to conventionally manufactured micro-milling cutters. The imprint is taken by means of reactive ion etching using a mask made of electroplated nickel. Within this dry etching process, characteristic values such as the etch rate and flank angle of the structures are critical and will be compared in a parameter analysis. At optimal parameters, an anisotropy factor of 0.8 and an etching rate of 0.34 µm/min of the silicon carbide are generated. Finally, the milling heads are diced and joined. In the final machining tests, the functionality is investigated and any signs of wear are evaluated. A tool life of 1500 mm in various materials could be achieved. This and the milling quality achieved are in the range of conventional micro-milling cutters, which gives a positive outlook for further development.

CO 54 (IET 24313) : An early maturing high yielding rice variety with marketable grain quality suitable for Tamil Nadu

The rice culture, CB 12588 evolved by crossing CB 04110 x CB 05501 was released as CO 54 during the year 2021 as an alternate variety to CO 51 and ADT 43 with 105-110 days duration. CO 54 is a medium tall variety with a profuse tillering habit, long erect leaves and droopy compact panicles possessing more number of filled grains per panicle. CB 12588  recorded an overall mean grain yield of 6354 kg/ha in various yield trials which was 10.83 per cent improvement over CO 51 and 10.35 per cent over ADT 53.  CO 54 has got high yielding potential due to its high agronomic and physiological efficiency and the maximum yield of 9259 was recorded in Bhavanisagar, Erode district under multi location trial. A High yield of more than 7000 kg/ha was realized in 16 locations in an adaptive research trial.  Besides yield, the culture CB 12588 has got marketable grain type i.e. medium slender grains with high milling outturn and head rice recovery percentage. Desirable cooking quality parameters like good linear elongation ratio, high volume expansion, intermediate amylose, soft gel consistency and moderate gelatinization temperature along with highly productive plant traits make CO 54 a suitable alternate variety to CO 51 and ADT 53. The culture CB 12588 is moderately resistant to blast, sheath rot, sheath blight and BPH under artificial conditions. The rice culture CB 12588 was released as CO 54 with a higher yield, better pest and disease resistance and good cooking quality in comparison to the checks CO 51 and ADT 53. It is suitable for cultivation during Kar/ Kuruvai/Sornavari/Navarai and the seasons/tracts wherever early maturing rice varieties are cultivated throughout Tamil Nadu.  Keywords: CO 54, Short duration, high yield, medium slender, cooking quality

Study on thermal-mechanical characteristics and crater wear of cemented carbide tools during the milling 508III steel

The water chamber head is made of 508III steel with high strength and hardness. The cemented carbide tool bears a large thermal-mechanical load during the cutting process, which leads to severe insert wear and damage as well as low tool life. Firstly, the milling experiments and finite element (FE) simulation were carried out to study the thermal-mechanical characteristics of tools. Secondly, the thermal-mechanical coupling simulation was carried out to explore the temperature field, strain, total deformation of the milling cutter, and the deformation and strain of the rake face of the milling insert respectively. Finally, the tool wear experiment was carried out, and the form, morphology, and energy spectrum of tool wear were analyzed, and the parameters of the crater wear were measured. The proposed crater wear rate was used as the characterization variable of tool wear, and the crater wear rate model was established to explore the wear evolution process of inserts preliminarily. The research results can provide theoretical support and experimental basis for the in-depth study of the tool failure mechanism and tool optimal design of the high-efficiency milling water chamber head.

Dynamics of the machine aggregate with a milling mechanism of the cotton bundle disassembler

The article covers the dynamics of the machine aggregate with a milling mechanism of the cotton bundle disassembler, taking into account the mechanical characteristics of the electric drive, technological resistance and torque of friction forces. The law of motion of the milling machine is defined. The dependence of the torque coefficient of the rubber bushing mounted on the milling heads on the vibrational value of the angular velocities of the rotating drive drum, the angular velocity of the drive rotor and torque is shown. Optimal values of the parameters according to the analysis of the connection graphs were recommended.

Influence of the Milling Conditions of Aluminium Alloy 2017A on the Surface Roughness.

The article presents the results and process analysis of the face milling of aluminium alloy 2017A with the CoroMill 490 tool on an AVIA VMC 800 vertical milling centre. The study analysed the effects of the cutting speed, the feed rate, the actual number of teeth involved in the process, the minimum thickness of the cut layer (hmin), and the relative displacement in the tool-workpiece system D(ξ) on the surface roughness parameter Ra. To measure relative displacement, an original bench was used with an XL-80 laser interferometer. The analysis of relative displacement and surface roughness allowed these factors to be correlated with each other. The purpose of this article is to determine the stable operating ranges of the CoroMill 490-050Q22-08M milling head with respect to the value of the generated relative displacement w during the face-milling process and to determine its influence on surface roughness. The research methodology presented in this paper and the cutting tests carried out allowed the determination of the optimum operating parameters of the CoroMill 490-050Q22-08M tool during the face milling of aluminium alloy 2017A, which are vc 300 m/m and fz—0.14 mm/tooth. Working with the defined cutting parameters allows all the cutting inserts in the tool body to be involved in shaping the geometrical structure of the surface, while maintaining a low vibration level D(ξ) > 1 µm, a low value of the parameter hmin > 1.5 µm, and the desired value of the parameter Ra > 0.2 µm

A precision prediction model for the transmission system of swing angle milling head considering machining and assembly errors

The performance of the milling head is affected by the machining and assembly process of the parts. The key to improving machining accuracy and reliability of swing angle milling head is to establish the precision prediction model. Therefore, a precision prediction model of swing angle milling head under the influence of multiple errors’ sources is built. The transmission and accumulation of machining and assembly errors along the assembly sequence path for the transmission system are carried out. All essential components on the assembly sequence path are considered. In addition, the secondary impact of the bearing seat hole is also taken into account. The source of the gear assembly errors is explained. The predicted range of transmission error based on the coupling relationship between assembly errors and transmission error is obtained. A precision experiment is carried out, and the result is within the predicted range. This research demonstrates that the errors' coupling relationship considered in this paper does exist and has an effect on transmission error, which provides a new idea for calculating transmission error of other gear systems.

Temperature measurement point optimization and experimental research for bi-rotary milling head of five-axis CNC machine tool

Temperature measurement point optimization and experimental research for bi-rotary milling head of five-axis CNC machine tool

Improved closed-loop tracking interferometer measurement for a five-axis machine tool with a bi-rotary milling head

Improved closed-loop tracking interferometer measurement for a five-axis machine tool with a bi-rotary milling head