Баланс напряжений и деформаций 
при холодной гибке листовой судостроительной стали

Изложен процесс разработки и внедрения авторами руководящего документа РД 5.05.08.04-20 «Методика разработки технологической инструкции на холодную гибку деталей из листовой судостроительной стали» в корпусном производстве АО «Восточная верфь» (Владивосток). Содержит результаты теоретических и практических исследований процессов, происходящих в структуре судостроительной стали нормальной и повышенной прочности при угловой и циркульной гибке деталей корпусов морских объектов. Приводятся расчётные формулы для назначения рабочих параметров гидропрессового оборудования и технологической оснастки. Предложенный авторами новый подход в процессе технологической подготовки производства позволил моделировать параметры прессового оборудования и оснастки для угловой гибки, с применением которой исключается образование дефектов. Предварительные расчёты необходимой мощности пресса позволяют использовать менее энергозатратное оборудование с уменьшением мощности на 25%. При этом расчётный выбор технологической оснастки позволяет сократить число рабочих циклов кромкогибочного пресса в два раза. Ключевые слова: пластическая деформация, угловая гибка, циркульная гибка, усилие пресса, параметры пресс-формы, параметры пуансона The process of development and implementation by the authors of the guideline document RD 5.05.08.04-20 Methodology for the development of technological instructions for cold bending of parts from sheet shipbuilding steel in the hull production of JSC Vostochnaya Verf (Vladivostok) is described herein. The paper covers the results of theoretical and practical studies of the processes occurring in the structure of shipbuilding steel of ordinary and high-strength during angular and circular bending of hull parts of offshore structures. Calculation formulas are given to properly assign the operating parameters of hydraulic press equipment and technological equipment. The new approach proposed by the authors in the process of technological preparation of production made it possible to simulate the parameters of pressing equipment and tooling for angular bending, with the use of which formation of any defects is excluded. Preliminary calculations of the required power of the press allow using less energy-consuming equipment with a power reduction of 25%. At the same time, the calculated selection of technological equipment allows to reduce the number of working cycles of the bending press in half. Keywords: plastic deformation, angular bending, circular bending, press force, mold parameters, punch parameters

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Technical solutions of vibration safety cold riveting performed ship repair

10.36652/0202-3350-2020-21-3-172-179 ◽

2020 ◽

pp. 172-179

Author(s):

A.Ya. Rozinov

Keyword(s):

Aluminum Alloy ◽

Cold Shock ◽

Vibration Disease ◽

Shock Absorbers ◽

Heating And Cooling ◽

The Press ◽

Press Equipment ◽

Technical Solutions ◽

Ship Repair ◽

Reverse Methods

The parameters of heating and cooling of rivets made of steel and aluminum alloy, as well as data of fi lling holes with these rivets during hot and cold riveting are compared. The features of the process of performing cold impact riveting by direct and reverse methods, as well as the possibility of reducing the force of this riveting by improving the closing heads and constructive transformation of the rivets themselves are considered. Features of physiological infl uence of cold shock riveting on hands, elbows and shoulders of workers are determined. Describes the construction of riveting hammers and supports with spring shock absorbers that prevent the disease of workers vibration disease, portable riveting presses of pneumatic and hydraulic action. A description of the press equipment and technology of bolt-riveting connections, allowing mechanizing the process of cold riveting is given.

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The analysis of an intense and deformation condition of shaving and glue mix in a rolling zone

Известия СПбЛТА ◽

10.21266/2079-4304.2016.215.229-243 ◽

2016 ◽

Author(s):

В.В. Сергеевичев ◽

А.В. Сергеевичев ◽

А.Е. Михайлова

Keyword(s):

Deformation Condition ◽

Composition Material ◽

Continuous Change ◽

Contact Points ◽

Processed Material ◽

The Press ◽

Dangerous Place ◽

Variable Tension ◽

Press Equipment ◽

Width Reduction

При прохождении стружечноклеевой массы по ленточному прессу и формования ее в изделие под вальцами происходит постоянное изменение свойств материала. От несвязной сыпучей композиции материал в результате пьезотермообработки должен преобразоваться в монолитное фасонное изделие. Силовое и температурные воздействия в процессе обработки вызывают в материале, а затем и в готовом изделии переменное напряженное состояние, которое в значительной степени определяет целостность и окончательные механические свойства готовой продукции. В настоящей статье исследуются напряженные состояния в наиболее опасном месте пресса – под профилирующим вальцом. Основная цель исследования заключается в попытке объяснить появление дефектов изделия и наметить конструктивные и технологические мероприятия по их устранению или хотя бы смягчению. При проведении предварительных экспериментов по изготовлению погонажных изделий из стружечноклеевой массы был обнаружен ряд основных недостатков. Большинство дефектов связано с процессом профилирования и возникают под профилирующим барабаном. Очевидно, причиной всех отмеченных дефектов являются экстремальные условия деформирования материала под барабаном и несоответствие термомеханического состояния обрабатываемого материала характеру деформирования. На основании проведенных исследований можно сделать основные выводы: продольный изгиб при прокатке изделий из стружечноклеевой массы представляет существенную опасность и может быть причиной расслоения изделий по ширине; уменьшение вредного влияния продольного изгиба по ширине изделия может быть достигнуто за счет его интенсивного разогрева и ограничения отверждения связующего под вальцами; диаметры профилирующих барабанов необходимо делать максимальными по конструктивным соображениям; оптимальным вариантом является профилирование на прямолинейных участках, где радиус равен бесконечности; необходимо обеспечить жесткую синхронизацию линейных скоростей по всем точкам контакта изделия с рабочими органами прессового оборудования. Такие условия автоматически удовлетворяется в гусеничном прессе, что дополнительно характеризует его достоинства. When shaving and glue mix passing through a tape press and its formations to product under rollers there is a continuous change of properties of material. From incoherent loose composition material as a result of a pyezoterm processing has to be transformed to a monolithic shaped product. Power and temperature influences in processing cause in material, and then and in a finished product a variable tension which substantially defines integrity and final mechanical properties of finished goods. In the present article intense states in the most dangerous place of a press – under the main roller are investigated. The main objective of research consists in attempt to explain emergence of defects of a product and to plan constructive and technological actions for their elimination or at least to mitigation. When carrying out preliminary experiments on production wooden materials from shaving and glue mix has been found a number of the main shortcomings. The majority of defects is connected with process of profiling and arise under a main drum. Obviously, extreme conditions of deformation of material under a drum and discrepancy of a thermomechanical condition of the processed material to nature of deformation are the reason of all noted defects. On the basis of the conducted researches it is possible to draw the main conclusions: the longitudinal bend when rolling products of shaving and glue mix constitutes essential danger and can be the cause of stratification of products on width; reduction of an adverse effect of a longitudinal bend on width of a product can be reached at the expense of its intensive warming up and restriction of curing binding under rollers; diameters of main drums need to be done maximum for constructive reasons; an optimal variant is profiling on straight sections where radius is equal to infinity; it is necessary to provide rigid synchronization of line speeds on all contact points of a product with operating parts of the press equipment. Such conditions it is automatically satisfied in a truck press that in addition characterizes its advantages.

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Dismantling the lining of an electrolyzer cathode unit for aluminum production using hydraulic press equipment and diamond cutting tools

Refractories and Industrial Ceramics ◽

10.1007/s11148-010-9205-9 ◽

2009 ◽

Vol 50 (5) ◽

pp. 321-323

Author(s):

Yu. V. Vasil’ev ◽

V. I. Kirko ◽

A. M. Petrov ◽

E. N. Chichuk

Keyword(s):

Cutting Tools ◽

Hydraulic Press ◽

Aluminum Production ◽

Diamond Cutting ◽

Diamond Cutting Tools ◽

Cathode Unit ◽

Press Equipment

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Selection of the optimal hydraulic drive for the press

10.33920/pro-2-2107-05 ◽

2021 ◽

pp. 50-60

Author(s):

A.A. Antsifirov ◽

V.A. Krivoshein

Keyword(s):

Technological Process ◽

Electric Motor ◽

Software Package ◽

Hydraulic Drive ◽

Hydraulic Press ◽

Topological Model ◽

Electric Motors ◽

Engine Operation ◽

The Press ◽

Selection Of

The research presented in the article is devoted to the selection of the electric motor of the hydraulic press drive with a nominal force of 5MN. The article presents the main characteristics and the description of the press operation using the means of mechanization of the technological process of pressure treatment. Using the Deform-3D software package, the process of stamping the crosspiece of the ZIL-130 cardan shaft was simulated. Based on the presented hydraulic scheme of the press, its topological model was formed in the PA-9 software package. The deformation force obtained in the course of modeling the technological process of stamping was used in the topological model of the press. Using a tabular cyclogram, the sequence of actuation of the end switches and hydraulic distributors during the stamping process is shown. In the article, two variants of engine operation were analyzed. Based on the results of the conducted research, it is necessary to focus on the second version of the 55 kW engine, the operation of which will provide the required characteristics of the hydraulic drive of the press, which in turn will allow for technological stamping operations. The simulation tools allow providing estimated information when selecting the necessary tools to ensure the optimal characteristics of hydraulic press drives. The article considered the variation of electric motors that differ from each other in nominal characteristics, with constant characteristics of the pump. For more accurate estimates of energy savings during the operation of the hydraulic drive, it is necessary to vary the characteristics of the pump in the simulation, and the best option is to form an experiment planning matrix when combining the characteristics of the electric motor and the hydraulic pump. This approach ultimately allows forming a function for which one can select a hydraulic drive from existing brands of electric motors and hydraulic pumps for presses of the corresponding range of nominal force.

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Fiber element modeling of circular double-skin concrete-filled stainless-carbon steel tubular columns under axial load and bending

Advances in Structural Engineering ◽

10.1177/13694332211065187 ◽

2022 ◽

pp. 136943322110651

Author(s):

Mizan Ahmed ◽

Qing Quan Liang ◽

Ahmed Hamoda

Keyword(s):

Stainless Steel ◽

Carbon Steel ◽

High Performance ◽

Mechanical Performance ◽

Axial Strain ◽

High Strength ◽

Offshore Structures ◽

Numerical Results ◽

Beam Columns ◽

Double Skin

Circular concrete-filled double-skin steel tubular (CFDST) columns with external stainless-steel are high-performance composite columns that have potential applications in civil construction including the construction of offshore structures, bridge piers, and transmission towers. Reflecting the limited research performed on investigating their mechanical performance, this study develops a computationally efficient fiber model to simulate the responses of short and slender beam-columns accounting for the influences of material and geometric nonlinearities. Accurate material laws of stainless steel, carbon steel, and confined concrete are implemented in the mathematical modeling scheme developed. A new solution algorithm based on the Regula-Falsi method is developed to maintain the equilibrium condition. The independent test results of short and slender CFDST beam-column are utilized to validate the accuracy of the theoretical solutions. The influences of various column parameters are studied on the load-axial strain [Formula: see text] curves, load-lateral deflection [Formula: see text] curves, column strength curves, and interaction curves of CFDST columns. Design formulas are suggested for designing short and beam-columns and validated against the numerical results. The computational model is found to be capable of simulating the responses of CFDST short and slender columns reasonably well. Parametric studies show that the consideration of the concrete confinement is important for the accuracy of the prediction of their mechanical responses. Furthermore, high-strength concrete can be utilized to enhance their load-carrying capacity particularly for short and intermediate slender beam-columns. The strengths of CFDST columns computed by the suggested design model are in good agreement with the test and numerical results.

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IMPROVEMENT OF THE PROCESS OF OPERATION OF THE GUIDE MOVING CROSSBARS OF HYDRAULIC PRESSES

STATE AND DEVELOPMENT PROSPECTS OF AGRIBUSINESS. In the frame of the XXIII Agribusiness Forum of the South of Russia and the Exhibition «Interagromash» Volume 2 ◽

10.23947/interagro.2020.2.197-199 ◽

2020 ◽

Author(s):

K.O. Kobzev ◽

◽

S.A. Vyalov ◽

E.S. Bozhko ◽

I.A. Zolotuhina ◽

...

Keyword(s):

Service Life ◽

Hydraulic Press ◽

Operating Conditions ◽

The Press ◽

Technical Solutions

This article deals with the problem of operating conditions of guide moving crossbars of hydraulic presses. Based on the study of hydraulic press operation processes, the need to develop and implement measures to ensure reliable and trouble-free operation of the press was identified. The conclusion justifies the idea that if these technical solutions are implemented, the service life of hydraulic presses will increase

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A Coupled Temperature-Displacement Numerical Analysis of Hydraulic Press Workspace

Volume 9: Mechanics of Solids, Structures and Fluids; NDE, Diagnosis, and Prognosis ◽

10.1115/imece2016-65480 ◽

2016 ◽

Author(s):

Jakub Jirasko ◽

Antonin Max ◽

Radek Kottner

Keyword(s):

Numerical Analysis ◽

Computational Model ◽

Automotive Industry ◽

Elevated Temperatures ◽

Compressive Force ◽

Hydraulic Press ◽

Metallic Materials ◽

Pressing Force ◽

Stress Criterion ◽

The Press

The analysis is performed on a hydraulic press which is intended for use in the automotive industry and is a part of a production line. The final phase of manufacture of interior and acoustic parts takes place in this press. These interior and acoustic parts are made of sandwich fabric which is inserted into the heated mould of the press and by treatment with a defined pressure (or, more precisely, a defined compression) and temperature, it is formed into its final shape. This press has a frame with four columns and it is not preloaded. Two double acting hydraulic cylinders placed on an upper cross beam exert the compressive force. Due to continuously increasing demands on the accuracy and quality of products not only in the automotive industry, it is necessary to ensure compliance with the accuracy of certain values of machine operation. Especially in this case, the value of accuracy substantially depends on the clamping plates of the press, for which a certain value of flatness is required, both at room temperature and at elevated temperatures. To achieve this accuracy, it is necessary to guarantee sufficient stiffness of the machine to resist the pressing force with the smallest deformation possible. Another crucial factor affecting the accuracy of the machine is heating of the heated clamping plates. Unequal heating of parts of the frame causes additional deformation that has to be quantified and eliminated. The main aim was to verify the design of the press by numerical computation and gather knowledge for modifying the topological design of the press so that it fulfils the required customer parameters of flatness and parallelism for different types of loading. A computational model of the press was created for the numerical solution of a coupled temperature-displacement numerical analysis. The analysis was performed using the finite element method in Abaqus software. The press is symmetrical in two orthogonal planes and the load of the press is considered to be centric. On the basis of these two factors it was possible to carry out the analysis by considering only a quarter of the press. The analysis was used to investigate the effects of static and combined loads from the pressing force and heat on the press. The influence of a cooling circuit located in the press frame for the reduction of frame deformation (and deformation of clamping plates) was investigated. Contacts were defined among individual parts to ensure the computational model had characteristics as close as possible to the real press. The analysis was solved as stationary, on the basis that the cooling of the tool between individual pressing cycles is negligible. The insulating plates are made of a particulate composite material which was considered to have isotropic properties depending on the temperature. For strength evaluation of composite materials all individual components of the stress tensor were examined according to the maximum stress criterion. Hook’s law was considered to be valid for the metallic materials. Von Mises criterion was used to evaluate the strength of the metallic materials. The geometry of the press was discretized using 3D linear thermally coupled brick elements with 8 nodes and full integration (C3D8T). There were approximately 174,000 elements in total. Design procedures for designing a press frame with higher work accuracy (flatness) were proposed with the example of the simplified model of the press table. With these methods it is possible to achieve times higher accuracy than is achieved with conventional method.

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Design and Manufacturing of Cylinder-Beam Integrated Hydraulic Press

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.397-400.157 ◽

2013 ◽

Vol 397-400 ◽

pp. 157-161

Author(s):

Wei Wei Zhang ◽

Xiao Song Wang ◽

Shi Jian Yuan ◽

Zhong Ren Wang

Keyword(s):

Driving Force ◽

Geometric Dimension ◽

Hydraulic Cylinder ◽

Hydraulic Press ◽

Force Distribution ◽

Section Modulus ◽

The Press ◽

The World ◽

Design And Manufacturing ◽

Institute Of Technology

For a cylinder-beam integrated hydraulic press (CBIHP), the hydraulic cylinder is also functioned as an upper beam. It is the key structural component that outputs the driving force to forge parts. Compared with the traditional three-beam and four-column hydraulic press which has a cylindrical hydraulic cylinder, the structure and force distribution are significantly different for CBIHP. It is able to have higher nominal force and larger section of plunger which the pressure is applied on when the contour geometric dimension is the same. Also, CBIHP has lighter weight and larger section modulus when the nominal force is the same than the traditional hydraulic press. Finally, a 6300KN cylinder-beam integrated hydraulic press, which is the first CBIHP in the world and designed by Harbin Institute of Technology (HIT) in 2012, is also introduced in this paper. It can be seen from the results of numerical simulation for the CBIHP that both of the stresses and displacements on the press in the loading process are allowable.

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