Grinding Machine Research Articles

ЕКСПЕРИМЕНТАЛЬНІ ДОСЛІДЖЕННЯ ШЛІФУВАННЯ ТОРЦІВ РОЛИКІВ ПІДШИПНИКІВ НА МОДЕРНІЗОВАНОМУ ДВОСТОРОННЬОМУ ТОРЦЕШЛІФУВАЛЬНОМУ ВЕРСТАТІ 3342АДО

Rolling bearing rollers are very important components of rolling bearings, the end surfaces of which are processed in mass and serial production on two-sided end grinding machines. They must be manufactured in accordance with the require-ments of GOST 25255-82 "Rolling bearings. Rollers cylindrical long. Technical conditions" made of bearing steel ShKh 15 according to GOST 801-78. The end surfaces of the rollers of rolling bearings are subject to high requirements for the accuracy of dimensions, shape and quality of the end surfaces while ensuring high processing productivity. Therefore, it is very important to find new reserves of the process.The analysis of research and publications showed the importance of the thermal effect and rotation of the workpieces in the processing zone during double-sided face grinding on the productivity, accuracy and quality of the processed end surfaces. This becomes even more important when grinding with crossed axes of wheelsand workpieces, since a special profile adjust-ment of the wheel is carried out, which makes it possible to obtain an area for removing the rough allowance and a calibration area on the surface of the wheel. At the same time, the entire allowance is cut inthe area adjacent to the calibration area. The calibration area at the entrance of the parts to the processing area does not participate in cutting the allowance, has high stability and forms the final accuracy of the end surfaces at the exit.The purposeof the article is to conduct experimental studies of the temperature on the ends of the machined bearing rollers along the processing coordinate and the rotation of the machined rollers in the closed zone between two grinding wheels along the processing coordinate on a modernized end-grinding machine 3342 ADO.The work proposed for the first time a new way of adjusting grinding wheels on a two-sided face grinding machine 3342 ADO, which made it possible to obtain a calibration area of grinding wheels of the correct geometric shape (without concavity). For this, the system of straightening of the basic face grinding machine 3342 ADO was modernized, which ensured the syn-chronization of the movements of the product feeding disc with the diamond pencil located on it for straightening the calibration area and the movement along the axis of the headstock of the rotating grinding wheel. All movements were controlled by the CNC system with a specially developed control program.

Influence of the punch with concave cutting-edge on the blanking force in micro punching process

Micro blanking machining is a promising manufacture technology to realize mass production of micro parts efficiently. In the process of blanking, the blanking force is significant to the punch, die, and sheet workpiece. In order to investigate the influence of cutting-edge shape of the punch on the micro blanking process, a self-developed micro combined EDM and blanking machine tool is applied in this paper. A punch with concave cutting-edge is capable to be fabricated online through a series of processing based on micro EDM: 3D milling, wire electrical discharge grinding and reverse EDM copy machining techniques. Then the punch and die are accurately matched online due to the preparation of them in the same coordinate system. Micro blanking parts and punching parts with the complex cross-sectional shape is obtained by using the online fabricated punch with flat cutting-edge and concave cutting-edge respectively in the workpiece of stainless steel SUS304 foil. The characteristic of blanking force varying with time indicates that the blanking force is significantly reduced in the case of concave cutting-edge, meanwhile, both blanking parts and punching parts have the high quality.

DVDLWC. SMOOTHING THE WORKING SURFACE DURING RESTORATION OF INTERNAL COMBUSTION ENGINE PARTS

When operating internal combustion engines, there is a problem of restoring cylinder liners. After wear, the cylinder liner is bored to the repair size, using boring and honing machines. Finding new effective processing methods is an urgent task. (Research purpose) The research purpose is smoothing the inner surface of cylinder liners by using a vibration-damping extension cord. (Materials and methods) The article proposes an epoxy-based adhesive composition and metal cables to reduce vibration during processing that ensure the compression state of the entire boring system. A special design of the vibration-damping extension of the boring mandrel have been developed. The article presents its description. A 6P12 vertical milling machine was used for research. Prototypes with an internal diameter of 80 millimeters were manufactured of steel 38 HMUA and steel 20. The Mitutoyo profilometer model SJ-410 was used to measure roughness. The rotation speed was changed from 80 to 500 revolutions per minute. (Results and discussion) The roughness of the surface layer of blanks made of 38HMYuA steel treated with a boring mandrel with a vibration-damping extension is four times higher on average than a traditional boring at all stages of the experiment, the roughness parameter Ra is 0.8. The quality of the surface layer of 20 steel blanks processed with a boring mandrel with a vibration-damping extension is twice as high on average as with a traditional boring at 80-315 rpm, the roughness parameter Ra is 1.6 and four times higher at 315-500 rpm, the roughness parameter Ra is 3.2. (Conclusions) The use of a vibration-damping extension will reduce the cost and complexity of restoring parts of internal combustion engines and remove special boring and internal grinding machines from the technological process.

The influence of the position and shape geometry of the counter-conical motion transmitter pin on the pitch fluctuation of the spiroid worm machined with adjusted shaft

The difference between the mathematical defined shape of the conical helicoid surface and the operating surface of the spiroid worm produced with axis adjustment on a thread grinding machine results – among other things –in thread pitch fluctuation. During the manufacturing of conical helicoid surfaces the transmission of the rotation from the main spindle to the worm shaft can be realised by a driving pin and an adjusted lathe dog. This article deals with the examination of the fluctuation of the thread pitch parameter occurring when using a counter-conical drive pin. The fluctuation is described here as a function of the position and the shape geometry of the drive pin.

Повышение энергоэффективности шлифовальных станков с числовым программным управлением

Повышение энергоэффективности шлифовальных станков с числовым программным управлением

Performance and Blood Profile of Grower West African Dwarf (WAD) Bucks Fed Graded Levels of Toasted Baobab (<i>Adansonia digitata</i>) Seed Meal

An experiment was conducted to evaluate the performance and blood parameters of West African Dwarf (WAD) bucks fed graded levels of toasted baobab seed meal for 84 days. Baobab seeds were washed, sun-dried and toasted uniformly using a cast iron pan. The toasted baobab seeds were crushed with a roller mill grinding machine to make baobab seed meal (BSM). The BSM was included at 0%, 25%, 50% and 75% levels in diets 1, 2, 3 and 4 respectively to replace soybean. Each treatment was replicated four times in a completely randomized design. Uncoagulated blood samples were collected from WAD bucks at the end of the 84 days’ feeding trial and analysed for packed cell volume (PCV), haemoglobin concentrate (Hb), red blood cells (RBC) and white blood cells (WBC). The mean corpuscular haemoglobin volume (MCV), mean corpuscular haemoglobin (MCH), platelets, neutrophils, lymphocytes, monocytes, eosinophils, and basophils were calculated using PCV, RBC and Hb. The blood meant for serological analysis was centrifuged at 1000 G for 10 minutes, after which the serum was separated and used for determining serum total protein (Tp), albumin, serum glutamic oxaloacetic transaminase (SGOT) and serum glutamic pyruvic transaminase (SGPT). The inclusion of baobab seed meal up to 50% in the experimental diet did not have any negative effect on the performance of the goats and did not pose any health challenge to the animals during the study period.

Razvoj nove CNC brusilice za 3+2 osno brušenje profilnih koturatih glodala

Due to the great expansion of woodworking, profile tools manufacturing has become current and in demand. In wood industry there are two large groups of tools: rotary and spindle milling cutters that can be profile or flat. The technology of making profile rotary milling cutters requires, apart from cutting, turning, milling, 5-axis grinding operation that is performed on a 5-axis CNC grinding machine with the A'OXYZC configuration.It is a machine of a very complex kinematics and high cost-price. The paper presents a new machine that has been built for 3+2-axis grinding - Profilator 100,used for industrial manufacturing of rotary and spindle profile milling cutters. The accuracy of measures and shapes of the profile cutters built on Profilator 100 is of a high level and in industrial exploitation the difference is not observed between the profile cutters built on 5-axis CNC grinding machines. Regarding technoeconomic cost-effectiveness, production costs of Profilator 100 are lower even by ten times compared to the cost-price of 5-axis CNC grinding machines of renowned world manufacturers such as Schneeberger and Volmer.

Tehnologija izrade profilnih koturastih glodala 3+2 osnim brušenjem na horizontalnom obradnom centru

The paper presents the technology of making brazed shaper milling cutters and with special reference to 5-axis grinding process (making of profile blades) on CNC grinding machine tool. Based on the analysis of the kinematics of the 5-axis grinding process, a new concept of profile milling tool production by a 3+2 axis grinding process on horizontal milling center was established. By Applying new concept, one tooth of profile tool was machined by grinding process. By obtained results, new approach for manufacturing of profile milling tools was verified.

Kegiatan Pabrikasi Mesin Giling Kopi Kering Merek BEJE Tipe GLK 20 di PT Bahagia Jaya Sejahtera

The development of coffee production needs to be supported by technological readiness, so that appropriate agricultural tools and machines (alsintan) are needed in the post-harvest processing of coffee. This study aims to identify the design drawing of a dry coffee grinder, produce a dry coffee grinder, and perform a performance test of the BEJE GLK 20 type dry coffee grinder. The research method used is a qualitative approach using a description method that explores and examines in depth the process activities. dry coffee grinder production. The manufacturing process for the dry coffee grinding machine has been successfully carried out by following the design that has been made and the stages in accordance with the machine design rules. The results of the dry coffee grinding power analysis with a power of 0.835 kW (1.12 HP) obtained a coffee grinder tooth capacity of 8.76 kg/hour from a total output capacity of 58.2 kg/hour.

Nanomachining characteristics of textured polycrystalline NiFeCo alloy using molecular dynamics

This work investigates the grinding process of a polycrystalline NiFeCo alloy through molecular dynamics (MD) simulation. The important factors that affect the grinding mechanics are cautiously investigated by analyzing the grinding force, resistance coefficient, local stress and strain, temperature, surface morphology, the evolution of structure and dislocation, which contain grinding velocity, machining depth, tool radius, and surface texture. The result shows that a higher machining velocity, greater grinding depth and tool radius lead to a larger grinding force and chipping volume, as well as a higher temperature of the substrate. While the grinding force, chipping volume, and temperature are the largest in the grinding of smooth surface compared to other surface textures due to the greater surface density. Moreover, the morphology of surface texture powerfully influences the pile-up volume, but slightly affects the shape of groove. The local shear strain and stress play a significant role in the grinding that explains the deformation mechanism in the substrate under the high pressure of cutting tool, and the grain boundary in polycrystalline is the control factor in the deformation behavior. Notably, the analysis of structure and dislocation evolution reveals that the nucleation and movement of dislocation caused plastic strain during the grinding show clearly the mechanism of subsurface damage. Besides, the dislocation motion is eliminated by grain boundary or interacts with each other to form new dislocation.

Scientific Substantiation of the Technology of the Functional Beverage, Based on the Rowan Juice with Vegetative Extracts Use

Topicality. Modern manufacturers of foodstuff and beverages are faced with the task of creating the new generation nutritive – sanative and functional, including drinks, that can have a positive impact on consumers’ health condition. Functional beverages are intended for systematic usage in the diet compound for all healthy population age groups; they are able to reduce the risk of diseases development, caused by nutrition, maintain and improve health state due to the presence of physiologically functional ingredients in their complement (vitamins, phenolic compounds, dietary fibers, carotenoids, organic acids, minerals). Aim and methods. The aim of this article is to substantiate the rowan juice choice for the functional meaning drink creation, to determine its composition and physico-chemical indicators, the selection of effective formula components with antioxidant effect, and the working of the non-alcoholic drink with sanative qualities technology. In this work standard organoleptic, physico-chemical and calculated research methods are used. Results. It was proved that the rowan juice should be used as the basis for the juice-containing beverage of functional meaning. For maximal juice extraction, it is necessary to pre-freeze the raw material, followed by its grinding and enzymatic preparation machining. Green tea and sage extracts, which are sources of antioxidant effect substances, were chosen as a supplement to the rowan juice. Discussion and conclusions. It is established that the non-alcoholic juice-containing beverage belongs to the category of functional foodstuff, as during its using the level of daily needs providing of ascorbic acid, β-carotene, pectin, bioflavonoids, catechins is within 10...50%. The scientific novelty of this research lies in the technology development of the juice-containing functional beverage on the basis of rowan juice with vegetative extracts use. The practical significance of the received results is in their usage at enterprises, producing non-alcoholic beverages, in restaurant industry and sanatorium-resort catering establishments.

Modeling of formation regularities of conical surfaces

The scheme of processing conical surfaces by grinding them to a flat tool is considered and a technical solution for the implementation of such processing is proposed. Using the created device allows implementing the group method of forming conical parts with a deviation of the generatrix of the cone from straightness of not more than ± 0.00012 mm. A mathematical model of the patterns of removal of stock from a conical part with a flat tool is developed. A formula is obtained for calculating the modulus of the sliding velocity at any point on the processed conical surface, which implements engineering methods for controlling the shaping of conical parts without conducting preliminary labor-intensive experimental studies. An optimization technique for the adjustment parameters of technological equipment was proposed. The most effective axicon processing modes were revealed at the stages of preliminary, medium and fine grinding, as well as at the polishing stage, depending on the technological heredity of the workpiece from the point of view of distribution of the stock to be removed over its surface. It has been established that changes in the eccentricity between the axes of rotation of the tool and the faceplate as well as the amplitudes of the reciprocating rotational movements of the latter practically do not affect both accuracy and processing productivity, therefore, in practice, these parameters can not be optimized, but their average values can be assigned. The operating modes of the basic lever grinding and polishing machine are established, at which the required accuracy of the working surface of the tool is provided, which directly affects the straightness of the generatrix of the cone. Studies of the regularities of the shaping of the side surface of a conical lens in the conditions of free grinding are carried out and the adjustment parameters of technological equipment that affect the quality and productivity of the processing process are determined.

Optimization of the precision gear grinding operation based on integrated information system

In accordance with the principles of hierarchical management, a comprehensive two-level management system is presented for the development and manufacturing of products for the stages of pre-production (the upper level of the management hierarchy) and for the actual production stage (the lower level of the management hierarchy). At the stage of pre-production, the gear grinding oper-ation design on the “MAAG”type machines was carried out. For this purpose, a technique for optimizing the gear grinding parame-ters for a two dish-wheel rolling scheme has been developed, a mathematical optimization model containing an objective function with restrictions imposed on it has been created. The objective function is the gear grinding machine time, which depends on theoperation parameters (gear grinding stock allowance, cutting modes, grinding wheel specification, part material) and the design fea-tures of the gears beingground (module, diameter, number of teeth, radius of curvature of the involutes). The article showsthat at the stage of pre-production,the gear grinding optimizationis a method of operation design. At the stage of actual production, a closed-loop automatic control system with feedback on the deviation of the adjustable value (gear grinding power) automatically supports the numerical power values that were found at the operation design stage, taking into account ensuring defect-free high-performance gear grinding (minimum number of working strokes and maximum longitudinal feeds). At this stage, i.e. when a robust longitudinal feed automatic control system is operating, the optimization carried out at the previous stage (pre-production) sets the functioning algorithm for the adaptive systemwithcorresponding control algorithm. Thus, at the production stage (when the gear grinding ma-chine is running), the operation optimization is a control method. Therefore, it is shown that with two-level control, the gear grinding operation optimization performs a dual function. On the one hand, it is a design method (at the pre-production stage), and on the other –a management method (at the actual productionstage). With this approach, i.e. with the integration of production and its preparation based on a single two-level management, the efficiency of a single integrated design and production automation system is significantly higher due to general (unified)optimization, rather than partialone.

A hybrid approach of case-based reasoning and process reasoning to typical parts grinding process intelligent decision

ABSTRACT After grinding, the machine tool spindle with high surface integrity has a significant impact on its subsequent service life. Therefore, it is necessary to create a reasonable process plan for the grinding process of the machine tool spindle. A hybrid method based on case-based reasoning (CBR) and process reasoning (PR) was proposed in this paper. The subjective and objective weights of feature attributes are determined in the CBR by the AHP method and the CRITIC method, respectively, and the similarities between the latest case and the retrieved case are calculated on the basis of the nearest neighbour algorithm. The most suitable process solution can be selected from the case database by means of CBR. PR is applied to solve the problem that the case cannot be retrieved through CBR or is unsatisfactory. In the case of the grinding machine spindle, the applicability of this technology was demonstrated. Consequently, the results revealed that the surface consistency of the spindle after grinding was substantially increased. A decision-making system based on the proposed approach was developed by using Qt 4.8.7 and SQLite 3. The results demonstrate the viability and efficacy of the hybrid CBR-PR method to rapidly generate process planning for specific parts.

ტექნიკური კერამიკის ფილების ბრტყელი ზედაპირებისა და პერიმეტრის ალმასური ხეხვის სპეციალური ჩარხი

In developed countries, material scientists are working intensively to create high-strength (metallic) technical ceramics. If such a material is created, it will be possible to manufacture such parts of power units (transmissions) of cars as shafts, turbines, etc. In the future, the latest composite ceramic materials with unique properties will gradually replace metals in the production of machine parts. Special device for diamond grinding of articles from composite, non-metallic, brittle materials (technical ceramics on the base of SiC, Al2O3; polycrystalline diamond, composite – Si + SiC + diamond etc.) is a universal flat grinding machine that enables to grind with high productivity both supporting main surfaces and lateral side surfaces – perimeter of an article of prismatic shape. It is also possible to grind substrates of other configurations – round, oval, etc. Grinding depending on sizes of articles can be done of both single and group of articles. The grinding takes place by the means of spring feeding of the article by pneumatic system that enables to prevent breakage of articles from brittle non-metallic materials in process of machining and obtain maximum high quality of the machined surface.

EXPERIMENTAL MILLING STUDIES ON HARDENED STEELS - A REVIEW

Hardened steels have numerous applications in the construction of molds and dies due, in particular, to their outstanding thermo-mechanical characteristics, such as wear resistance and high stiffness, but especially dimensional stability at high temperatures. Machined surfaces are conditioned to have important tribological characteristics. Thus, a high quality of machined surfaces is achieved by milling processes with high cutting speeds. These types of processes even manage to replace grinding or electro-erosion machining processes with a solid electrode. The paper presents a review of experimental studies in recent years from industry and scientific research. Issues are outlined which justify the utility of machining hard metals by machining processes, with a focus on machining by milling processes. Starting from input parameters, such as technological parameters, blank material, cutting tool material and machining environment, their influence is analysed on output parameters, such as chip morphology, cutting tool wear and surface integrity.

Deworming the Grinder for Successful Extrication of a Mangled Hand: A Case Report and Review of Literature

Grinding machine injuries are known to cause severe mutilating injuries of the upper limb. In some cases, the machinery equipment may still be attached to the limb when the patient reaches the hospital. In treating these injuries, the patient’s hemodynamic status should be the first priority of resuscitation. Following this and whenever possible, a reversal of the grinding mechanism should be done to free the limb as this would allow assessment of the extent of zone-of-injury prior to starting the surgical procedure. We report a case of a 28-year-old male who sustained a mangled hand injury that was successfully extricated from an industrial grinding machine, thereby allowing preservation of precious length of the limb during surgery. This case highlights the importance of adhering to safety precautions at the workplace to reduce the risk of potential occupational hazards when dealing with machinery equipment.

Optimal allocation of product reliability using novel multi-population particle swarm optimization algorithm

Reliability optimal allocation is a critical method in engineering and operation fields to improve and ensure product quality. However, conventional model generally uses the single objective with research and development (R & D) cost or product reliability. Moreover, the popular particle swarm optimization (PSO) algorithm solving the model has insufficient global search ability. In this paper, a novel reliability optimal allocation method is developed based on double-objective model and multi-population PSO (MPPSO) algorithm. The cost function is established considering all the cost related to reliability using analytical hierarchical process (AHP) and ordered weighted averaging (OWA) operator. Multi-population particle swarm optimization algorithm is developed based on information exchange mechanism among subpopulations. In the algorithm, the inertia weight is optimized by chaotic map, and different mutation operations are carried out on the subpopulations. An illustrative example, which implements to computer numerical control (CNC) grinding machine, is presented to illustrate the practicality and application of the proposed method. Finally, the comparison and analysis are implemented to show the advantage of proposed model and MPPSO algorithm.

Feasibility of Optical Flow Field Measurements of the Coolant in a Grinding Machine

For industrial grinding processes, the workpiece cooling by metalworking fluids, which strongly influences the workpiece surface layer quality, is not yet fully understood. This leads to high efforts for the empirical determination of suitable cooling parameters, increasing the part manufacturing costs. To close the knowledge gap, a measurement method for the metalworking fluid flow field near the grinding wheel is desired. However, the varying curved surfaces of the liquid phase result in unpredictable light deflections and reflections, which impede optical flow measurements. In order to investigate the yet unknown optical measurement capabilities achievable under these conditions, shadowgraphy in combination with a pattern correlation technique and particle image velocimetry (PIV) are applied in a grinding machine. The results show that particle image velocimetry enables flow field measurements inside the laminar metalworking fluid jet, whereby the shadowgraph imaging velocimetry complements these measurements since it is in particular suitable for regions with spray-like flow regimes. As a conclusion, optical flow field measurements of the metalworking fluid flow in a running grinding machine are shown to be feasible.

Design of a compact grinding machine

The availability and cost of tools are among concerns to the public and industries as key operation device used either for commercial or maintenance purposes such precision grinders or polishing machines are usually expensive. Assorted grinding tools in the market differ in terms of cost, required user proficiency levels and have different tool designs that can lead to limitations of flatness of ground surface and significant vibrations with prolonged use. The aim of this study is to develop a design compact grinder that is able to perform precise grinding and polishing while being cost efficient. Both functionality and ergonomic aspects were taken into consideration with market standards derived from datasheets. An initial design of the grinding machine was made using SolidWorks CAD software. A prototype was subsequently constructed and tested by using typical metallurgical sample preparation process with test parameters of grade of grinding paper and usage of lubricant. Microscopic image of ground specimens showed improvement in the quality of grinding with emery paper grades from coarse to fine grits with lubricant during the grinding process. Moreover, the designed compact grinding machine showed better surface finish when compared to using a typical angle grinder on aluminium sample.