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The use of modern machining centers with wide technological capabilities and the active development of productions with a small-scale form of organization necessitates an increase in the efficiency of fixtures capable of ensuring sufficient accuracy of machining with minimal costs.Classical approaches to the design of fixtures do not always allow machining with one installation with high-performance cutting conditions, so it is necessary to move the new approaches that allow maximum tool availability, which is important for the competitiveness of enterprises.The analysis of research and publications on numerical modeling and experimental research on the processing of parts of a complex shape that have insufficient rigidity showed that the issues of static research of the stress-deformation state of fixtures with incomplete locating have received little attention in the scientific literature.The purpose of the article is to experimentally demonstrate the possibility of machining non-separable connecting rods in machine tools with incomplete basing and fastening only on unprocessed surfaces in one installation with the achievement of all the necessary indicators of dimensional accuracy.The work presents for the first time an improved fixture with an incomplete location for machining connecting rod-type parts, and experimental studies of its stress-strain state in static mode are performed. The determined values of stresses and displacements compared with the previously proposed machine tool showed its technical advantage in bearing capacity for loads acting during machining.In this work, it was experimentally proven for the first time that the design of the improved fixture for machining connecting rods is capable of providing the necessary machining accuracy under static load and at the same time has a margin of accuracy thatexceeds the value of deformations by 1.5...2.5 times. The presented results and the positive experience of manufacturing a sample of a fixture can be used for its further research in a dynamic mode directly during machining, as well as for the design of technological equipment for parts of other classes, using an approach that involves incomplete locating of the workpiece

The article analyzes the causes of the situation with the appearance of manufacturing errors and the lack of the necessary technical requirements to perform a pin conical joint his intended purpose. The analysis was performed based on geometric construction of the assembly dimensional chain of two parts to be connected and a conical pin with a taper 1:50 according to GOST 9465-79, which is used in the pin joints of pumping equipment. The geometric analysis included the separation of deviations into linear dimensions and angular deviations. The values of the angular deviations were reduced to the linear values of their projections along the axis of the pin, to determine the tolerance on the end height protrusion of the pin above the surface of the connecting parts. Also, the unfoundedness of assigning the roughness index of the hole under the pin at the level of Ra 1.6 μm and its inexpediency when it is impossible to ensure the required contact length is theoretically proved and the solution of this contradiction is proposed. A detailed analysis of the technical requirements for drawings of pumping equipment units containing pin conical joints and paragraphs of the relevant standards, which resulted in the inconsistencies, and offer recommendations that will ensure the quality of the joint following its official purpose. Analysis of the geometric parameters of pin conical joints for the first time allowed to determine the dependence of the height of the pin end protrusion above the surface of the connecting parts and the tolerance for this parameter, as well as to propose mathematical dependences for their determination. The presented dependencies can be used in practice for a reasonable calculation during the design of pin conical joints in pump nodes and in machine-building enterprises where such joints are used. For the first time, the determination of the tolerance for hole size for machining conical reamers is presented, and the formula for calculating this parameter is proposed, which is given in the recommendations for their use in machine building enterprises and products containing pin conical joints.

На основі геометричного аналізу області контакту штифтового конічного з’єднання встановлено параметри, щовпливаютьнатипконтактуотворуіштифта. Уперше встановлена та запропонована у вигляді формули залежність величини відхилення кута отвору під штифт від допусків на параметри розгорток конічних. У роботі як рекомендації конструктору для проєктування штифтових конічних з’єднань із конусністю 1:50 представлені графіки залежності відхилення кутів отвору та штифтів класів точності А і В від їхнього номінального значення. Також визначена сумарна відносна похибка відхилення кутів отвору та штифта від номінального значення кута для усіх стандартних значень діаметрів штифтових конічних з’єднань.

Assurance of accuracy for machining parts and their work’s reliability is achieved using fixtures with the required accuracy of the locating and the workpiece reliable fixing. The expansion of state-of-the-art metal-cutting equipment’s technological capabilities necessitates using advanced fixture designs to be fully utilized. It requires the application of new approaches and the necessity of advanced fixture design. Fixture design for complex parts machining can reduce the auxiliary time for setup remains especially relevant. A flexible fixture design that provides tool accessibility multiaxis machining of fork-type parts for one setup is proposed. Refusal of full locating, application of industrial robots, and two fixtures for parts machining allows combining auxiliary time with cutting time. The numerical simulation results confirmed that the fixture meets all the strength, accuracy, and stiffness parameters. It allows the application of intensive cutting modes, which will provide the greatest efficiency when using modern machine tools and cutting tools. Oscillation amplitudes in the work surface positions do not exceed these surfaces’ size tolerances.

The rapid development of manufacturing in recent years has led to a significant expansion of the technological capabilities of modern metal-cutting equipment. Therefore, the modern approach to intensifying production requires an advanced fixture design. Design and manufacture of flexible fixtures capable of machining similar shapes and sizes of complex geometry parts reduce setup time. The article aims to design flexible fixtures for parts such as one-piece connecting rods under incomplete locating conditions. The advantages are the minimum number of parts and tool availability for multi-axis machining connecting rods in one setup. This approach, combined with up-to-date machining centers and industrial robots, can increase the production efficiency of manufacturing non-removable connecting rods. This effectiveness is in a decrease in the number of operations by 5–7 times, fixtures—by 3–4 times, and machine tools—by 3–5 times, depending on the type of a non-removable connecting rod and its design features. The numerical simulation results of the proposed fixture design confirmed the comprehensive technological capabilities and dynamic characteristics. Particularly, a decrease in displacements and oscillation amplitudes up to 7% compared to the full-basing locating chart was provided. It is determined that the system “fixture–workpiece” entirely meets all the strength, accuracy, and rigidity parameters, which allows you to perform machining with intensive cutting modes. The amplitudes of oscillations do not exceed the tolerances on the dimensions of these surfaces, established by requirements for non-removable connecting rods, and all displacements are elastic. During numerical simulation, the workpiece position remained stable at all machining steps.

Анализируется проблема подготовки специалистов заведениями высшего образования в области проектирования и изготовления насосного оборудования для предприятий Украины. В работе детально рассмотрена организационная структура, присущая предприятиям машиностроения Украины и стран СНГ, и выполнено ее сравнение со структурой предприятий развитых стран с рыночной экономикой. Выявлены причины низкой конкурентоспособности машиностроительных предприятий Украины и предложены пути их решения. Приведены примеры организации структуры предприятий Украины специализирующихся на изготовлении насосного оборудования, а также показано влияние их структуры на конкурентоспособность. На основе анализа структурных схем взаимодействия отделов и бюро предприятий насосостроения Украины и развитых стран, а также потребностей рынка труда определен круг обязанностей современного инженерно-технического работника для конкурентоспособного предприятия. Показана роль современных инженерно-технических работников в конкурентоспособности продукции. Предложен новый термин – «инженер-разработчик», который наиболее точно характеризует современного инженерно-технического работника и отвечает потребностям рынка труда. Сформированы требования к инженерно-техническим работникам предприятий Украины в области насосостроения. Предложено объединение функций конструкторских, технологических подразделений и отдела маркетинга в подразделение инженера-разработчика для сокращения времени выпуска продукции, что позитивно отразится на конкурентоспособности предприятия. В работе приведена методика подготовки данных кадров с точки зрения потребностей производства на базе заведений высшего образования в рамках углубленного межкафедрального сотрудничества на основе кафедр технического направления при содействии кафедр управления и экономики. В методике приведены этапы подготовки будущих специалистов, включающие отбор и формирование групп, руководство, и процесс трудоустройства, а также перечень базовых, и дополнительных дисциплин для студентов образовательно профессиональной программы «Гидравлические машины и аппараты» и смежных с ней., It is analyzed the problems of specialists training by higher education institutions in the field of designing and manufacturing pumping equipment for enterprises in Ukraine. In the work examines details organizational structure inherent in engineering enterprises of Ukraine and the CIS countries, and comparativeness it with the structure of enterprises in developed countries with a market economy. The reasons for the low competitiveness of engineering enterprises in Ukraine are identified and ways to solve them are proposed. Examples of the organization structure of Ukrainian enterprises specializing in pumping equipment manufacture are given, and the influence of their structure on competitiveness is shown. Based on the analysis of the structural schemes of interaction between departments and bureaus of pumping enterprises in Ukraine and developed countries, as well as the needs of the labor market, the responsibilities of a modern engineering worker for a competitive enterprise are determined. The role of modern engineering workers in the competitiveness of products is shown. In article proposed a new term – “engineer-creator”, which most accurately characterizes the modern engineering and technical worker and meets the needs of the labor market. Requirements for engineering and technical workers of Ukrainian enterprises in the field of pump engineering have been formed. It is proposed to combine the functions of design, technological units and the marketing department into a subdivision of a engineer-creator to reduce production time, which will be positively affects by the competitiveness of the enterprise. In the article presents a methodology for training these personnel from the point of view of production needs on the basis of higher education institutions as part of in-depth inter-department cooperation on the basis of technical departments with the assistance of management and economics departments. The methodology describes the stages of training of future specialists, including the selection and formation of groups, management, and the process of employment, as well as a list of basic and additional disciplines for students of the educational and professional program "Hydraulic Machines and Devices" and related ones., Аналізується проблема підготовки фахівців закладами вищої освіти в області проектування і виготовлення насосного обладнання для підприємств України. У роботі детально розглянута організаційна структура, притаманна підприємствам машинобудування України і країн СНД, і виконано її порівняння зі структурою підприємств розвинених країн з ринковою економікою. Виявлено причини низької конкурентоспроможності машинобудівних підприємств України та запропоновано шляхи їх вирішення. Наведені приклади організації структури підприємств України, що спеціалізуються на виготовленні насосного обладнання, а також показано вплив їх структури на конкурентоспроможність. На основі аналізу структурних схем взаємодії відділів і бюро підприємств насособудування України і розвинених країн, а також потреб ринку праці визначено сферу обов'язків сучасного інженерно-технічного працівника для конкурентоспроможного підприємства. Показана роль сучасних інженерно-технічних працівників в конкурентоспроможності продукції. Запропоновано новий термін - «інженер-розробник», який найбільш точно характеризує сучасного інженерно-технічного працівника і відповідає потребам ринку праці. Сформовано вимоги до інженерно-технічних працівників підприємств України в області насособудування. Запропоновано об’єднання функцій конструкторських, технологічних підрозділів та відділу маркетингу в підрозділ інженера-розробника для скорочення часу випуску продукції, що позитивно відобразиться на конкурентоспроможності підприємства. В роботі наведено методику підготовки даних кадрів з точки зору потреб виробництва на базі закладів вищої освіти в рамках поглибленої міжкафедральної співпраці на основі кафедр технічного напряму за сприяння кафедр управління та економіки. У методиці наведені етапи підготовки майбутніх фахівців, що включають відбір і формування груп, керівництво, і процес працевлаштування, а також перелік базових, і додаткових дисциплін для студентів освітньо-професійної програми «Гідравлічні машини та апарати» та суміжних з нею.

The chapter is devoted to the solving of the problem of increasing the efficiency of lever-type parts machining due to the introduction of flexible fixtures ensuring multi-axis machining. The relationship between the design and technological parameters of the parts were discovered, which is the fundamentals for the analysis of parts and the search for the fixture layout for the given production conditions. An innovative approach to the design of technological processes for lever-type parts machining is proposed, which is based on the principle of intensification of machining processes, design and technological features of the parts, functional and technological capabilities of modern metal-cutting machine tools. A mathematical model of machining accuracy of parts depending on the level of fixture flexibility is obtained. It is analytically and experimentally proved the feasibility of using flexible fixtures for multi-axis machining of lever-type parts in multiproduct manufacturing.

The paper is dedicated to the increase of the efficiency of multiproduct manufacturing. The experience in designing the manufacturing processes of manufacturing machining parts, such as connecting rods, is analyzed. A progressive manufacturing process based on the concept of intensification of machining and application of multiaxis equipment is proposed. This approach made it possible to reduce the complexity of the manufacturing process in drilling, milling, and boring operations. Research has been conducted on the design, optimization, modeling, and production of fixtures for multiproduct manufacturing. The design of a flexible fixture for machining non-detachable connecting rods is provided, which allows adjustment of locating and clamping elements in a certain size range. Studies have shown an increase in machining productivity of the proposed manufacturing process from 1.7 to 3.9 times depends on batch size.

Fixtures play an important role in the production of high-quality and competitive products, especially in the context of multiproduct manufacturing, which requires fast reequipment in the transition to the machining of parts of the other type. The article deals with the problem of determining the optimal dimensions of the fixture functional elements for machining of the lever-type parts within a given size group. The purpose of the research is to increase the efficiency of machining by optimizing the design of a flexible fixture through the proper choice of parameters of the fixture elements. Fixture configurations were analyzed by means of the parametric optimization algorithm. The reserves for fixture optimization were revealed, and possible variants of the fixtures for the limiting size of the levers within the given size group were investigated. Based on the research of static structural, modal, and harmonic analyses of fixture configurations, optimal parameters of each element of the flexible fixture were found out. The optimal design of the fixture is proposed, which can provide multiaxis machining of all sizes of levers within a given size group with the required accuracy.

In this article, the new configuration of fixture was proposed for ensuring the sufficient tool accessibility, which allows carrying out multiaxis machining of levers in one setup. The research based on numerical simulation was confirmed that the proposed fixture corresponds to all the accuracy parameters. Workpieces from steel, cast iron and aluminium alloy were investigated within the simulation. The values of displacements and stresses occurring during machining are less for proposed fixture in comparison with the existing fixtures that was confirmed by the deflected mode analysis. The modal analysis proved that the proposed fixture has much higher value of eigenfrequency than the other fixtures. To optimize the machining, the dependences for displacements and stresses on the cutting depth were determined. Oscillations of the system “fixture–workpiece” during machining were investigated for various manufacturing steps of levers machining of the fixtures from different fixture systems. The results of harmonic analysis showed that the dynamic stiffness of the proposed fixture was higher than that for the dedicated and modular fixtures. The oscillation amplitudes in the places of machined surfaces in the proposed fixture do not exceed the tolerance requirements for lever manufacturing.

Flexible fixtures increasingly acquire an extension in up-to-date manufacturing engineering, albeit an attempt to determine the impact of the flexibility on the fixture accuracy parameters was not performed in previous research. The aim of this work is determination the opportunity to provide dimension accuracy for lever machining in the high-flexible fixture. Experimental values of displacements of the elements of the system "fixture - workpiece" for the different levels of fixture flexibility were obtained by means of finite elements analysis. On the example of levers machining it was stated that increasing the fixture flexibility allows receiving in a certain range the required dimension accuracy of the parts. Displacements were used for obtaining the mathematical model of the fixture accuracy depending on fixture flexibility. This model in case of levers machining describes by nonlinear function of evaluated flexibility indicators. The method of quasilinear evaluation of the parameters was used for identification the design flexibility by minimization of the total square deviation using the iteration procedure.

The ways of intensification of machining complex parts of vehicles on the modern metal-cutting equipment were described. The classification of parts such as levers was developed on the basis of design and technological features. Based on the developed classification the structural code that allows to encode any lever design was proposed. The structural code can be used in computer-aided fixture design and in information retrieval systems for selecting optimal fixture for levers. The reasonability of intensification of parts machining such as levers was substantiated, the typical manufacturing process was analyzed, and opportunities for optimization subject to current trends in machining and technological capabilities of modern equipment were identified. The adjustable locating-and-clamping module characterized by high level of flexibility was proposed for CNC multiaxis machining operation. Comparative analysis of manufacturing processes by labor content, quantity of fixtures and machine tools, number of setups, and production area was performed.