Press Frame Research Articles

HYDROSTATIC TESTING TECHNOLOGIES IN THE METALLURGICAL INDUSTRY

The development of the new test presses is based on the requirements of modern technologies for the extraction of oil from ultra-deep wells and shale gas to test the strength of pipes up to higher test pressures. The hydrostatic test algorithm involves pushing test heads onto the ends of the pipe to seal the internal cavity of the pipe. Then the pipe is filled with a water emulsion and the pressure of this emulsion is increased to the value specified in regulatory documents. For high-pressure hydrostatic testing of oil and gas pipes, the most advantageous method is the external sealing of pipes using segmental sleeves. The mechanical testing equipment should take into account the compensation of axial forces from the pressure of the test fluid inside the pipe, for which purpose the press frame should be power-operated. The most common power scheme of test presses is considered, in which all axial forces arising from the action of the fluid pressure inside the pipe on the test heads are compensated by reaction forces in the power columns. The front head is rigidly connected to the columns, and the rear head is placed on a movable carriage to compensate for uneven pipe lengths. In the working position, the rear carriage is fixed to the columns with special locking mechanisms. It is advisable to improve the quality of the test by improving the design of the hydraulic system elements and studying the processes during the rise and retention of high pressure. The test pressure inside the pipe is created mainly by means of a hydraulic pressure multiplier. The parameters of the multiplier: multiplication factor, piston diameter and stroke are selected depending on the required test pressure, length and diameters of the pipes to be tested. Research on high-pressure hydraulic systems of the multiplier type is of particular interest at present.

‘Social Darwinism has moved to the cycle path’: framings of micromobility in the Dutch and British press

The media’s agenda-setting function in terms of selecting and presenting issues to the public and policymakers is crucial for the urgently needed transition towards more sustainable mobilities, including how the media frames micromobility. Media framings are representations, a key component of mobility, alongside physical movement and practice, all involving power relations. Drawing on mobility studies and discourse analysis, this paper compares how the Dutch and British national press frame micromobility. We identify five frames of micromobility: (1) as sustainable and active shift, predominant in the British press; (2) as disruption of the Dutch pedal-powered cycling regime; (3) as catalyst of conflicts in public space, both in the Dutch and British press; (4) around the shortcomings of micromobility regulations in both contexts; and (5) concerning lifestyle in the Dutch context. We demonstrate how media framings of micromobility only limitedly discuss its potential to transition from automobility, focusing instead on social status changes, regulatory challenges, and conflicts between different forms of micromobility, that are already marginalized. Our findings emphasize the urgency to put the transition from automobility—the elephant in the room—on the agenda.

Research on the Application of Structural Topology Optimisation in the High-Precision Design of a Press Machine Frame

This article aims to optimise the structure of a press machine to enhance its stability and accuracy, as well as reduce the frame deformation during processing. The outer supporting frame of the JH31-250 press machine (Zhejiang Weili Forging Machinery Co., Ltd, Shaoxing, China) is used as a typical sample for exploring optimisation. Commercial software is utilised to conduct a finite element analysis on the three-dimensional model of the press machine frame. A topological optimisation algorithm using the solid isotropic microstructures with penalisation (SIMP) method is then applied to improve the structure of the press frame. The size of the topological structure is further refined with the response surface method and particle swarm optimisation method to ensure it is more relevant to engineering application. The analysis results indicate that the initial frame’s deformation under the static conditions is 0.4229 mm, and after optimisation, the deformed structural displacement is 0.2548 mm, a decrease of 39.75%. Additionally, a simplified experimental method is designed to effectively validate the simulation and the proposed design.

Perancangan Alat Press Hidrolik Kapasitas 20 Ton

A press tool is a tool to help shape, bend, cut products from sheet metal (plate) base material which is operated using a press tool. To increase effectiveness and productivity, currently many hydraulic systems are combined with other systems such as electrical/electronic, pneumatic and mechanical systems so that more optimal hydraulic system work can be obtained. This press applies pressing or loading movements using hydraulic power. In order for the pressing process to be even or precise, one cylinder is needed which moves the top plate (Punch). The working load on the single acting cylinder has a maximum capacity of 20 tons. The design of this press tool is designed by following the type and shape of the selected material sample. The design of this press tool aims to make the user's work easier to get more precise press results. The material used is profile steel. Simulation results on the press frame: frame length 400 mm, frame width 600 mm, frame height 850 mm, frame strength 16407 N/m2

Research on a double frame hydraulic press with PTS using winding steel wires

The desired preloading effect of a hydraulic press frame parts (upper/lower semi-circular beams and columns) with Pre-Tightening Stress (PTS) by means of Winding Steel Wires (WSW), which is directly related to the reliability and normal safe operation of the hydraulic press. The deformation of the Hydraulic Press Column (HPC) is an important indicator of the optimal preloading effect of the hydraulic press. As a technical bottleneck, the continuous cumulative deformation of a HPC under seven time-varying steps is critical issues especially in theoretically calculated for a 20 MN double-frame hydraulic press with PTS using WAW. A solid model with a PTS frame is pre-designed by 3D software, and two simulation methods, equivalent pressure loading and equivalent temperature loading, are used to simulate and analyze the continuous cumulative deformation of the HPC under each step in Ansys Workbench software. By comparing the deformation and error analysis in the three cases above, the feasibility of the two simulation methods is verified, which leads to the advantages and disadvantages of each method in order to guide the subsequent design.

Numerical calculation of a 20MN heavy duty hydraulic press for analyzing the double frame pre-stressed steel wire winding

The expected preloading effect of a hydraulic press frame parts (upper/lower semi-circular beams and columns) with pre-stressed by means of Winding Steel Wires which is directly related to the reliability and normal safe operation of the hydraulic press. The deformation of the Hydraulic Press Column (HPC) is an important indicator of the optimal preloading effect of the hydraulic press. A novelty of this project is to break through a bottleneck technology, the continuous cumulative deformation of a Hydraulic Press Column under seven time-varying steps is critical issues especially in theoretically calculated for a 20 MN double-frame hydraulic press with pre-stressed using WAW. A solid model with a pre-stressed frame is pre-designed by 3D software, and two simulation methods, equivalent pressure loading and equivalent temperature loading, are used to simulate and analyze the continuous cumulative deformation of the HPC under each step in Ansys Workbench software. By comparing the deformation and error analysis in the three cases above, the feasibility of the two simulation methods is verified, which leads to the advantages and disadvantages of each method in order to guide the subsequent design.

Evaluasi Efektivitas Kinerja Filter Press Plate and Frame pada Proses Pemanenan Spirulina sp

Spirulina sp can be used as raw material for making masks and medicines. This research wasconducted to determine the effectiveness of the performance of using a Filter Press (plate and frame) in harvesting Spirulina sp. In this study, Spirulina was cultured in 60 L styrofoam containers with different photoperiods (light/T and dark/G), for 12 hours per day (12T-12G). Parameters observed include dry biomass. For 12 hours per day (12T-12G), Press Filters with 2 and 3 plates were used and pressure of procrsess are 1, 1.5, and 3 Psi. In this study, Spirulina sp can grow well with a concentration of 0.6636 gr mL-1. The filter press plate and frame can be used to harvest Spirulina Sp with the optimum conditions for the Spirulina filtration process by pressing two psi and the number of plates 3, where the highest amounts of filtered Spirulina are 39.653 g with a filtering time of 2 x 103 seconds.

Framing migration in the Greek press; An analysis of the ‘Evros events’ in left, liberal, and far-right newspapers

In this article we focus on one important event related to the Greek dimensions of the so called refugee crisis in Europe. This event took place during late February and March 2020 and is known as the Evros events that occurred when Turkey decided to open its European borders to the refugees. Greece responded by closing its land borders with Turkey, and by halting the asylum application process. The area surrounding the Evros River in Greece became heavily policed by the Greek police and the EU’s Frontex border police, further aided by various citizen militias consisting of Greek and other EU nationals. This research analyzes the newsmedia coverage of the specific incident through a qualitative frame analysis on news articles written by five Greek newspapers that have different political affiliations. The analysis then answers a two-fold research question: how did the Greek press frame the Evros events, and how did these frames contribute to the public debate around migration in the country.

Effect of Preload on Frame Stiffness of 1600 kN Closed Double Point Mechanical Press

A 1600kN closed double point press is used for the punching process of U-shaped longitudinal beam and more than 10 independent die frames are arranged. Different holes require different punching forces, and multi-station punching will cause eccentric loads, while preload and off-centre load are important factors affecting the precision of the combined frame of closed press. In this paper, a 1600kN press combined frame is designed based on the U-shaped longitudinal beam punching process and the three dimensional model of 1600kN press frame is established by Solidworks. The finite element analysis of preload, symmetrical load and off-centre load was carried out by Ansys Workbench. The deformation of upper beam in Z direction and the relationship between eccentric load factor i and the maximum deformation difference △h can be obtained, which has important application value to improve the manufacturing accuracy of this type of press.

Structural Analysis and Size Optimization of a Fine-Blanking Press Frame Based on Sensitivity Analysis

The fine-blanking press, which has been widely used in the sheet-cutting industry, is high-end equipment. The frame is a core component of the fine-blanking press. In this paper, the sensitivity analysis and size optimization method were used to optimize a fine-blanking press frame. First, a shell element model of the frame was established to analyse the mechanical properties of the initial frame. Then, the mathematical expressions for sensitivity analysis and size optimization of the frame were formulated. Based on the established model, the response sensitivities for plate thicknesses were analysed, and a 12.94 % weight reduction was achieved through size optimization. Moreover, the effect of material distribution on dynamic performance was investigated. The result indicated that for a constrained structure, distributing material close to the constraint location increases the modal frequencies.

The discursive construction of the moral and legal statuses of fansubbers in the Chinese press 2006–2018

Fansubbers (short for “fan subtitlers”) are confronted with a moral-legal dilemma in China. On the one hand, they are highly appreciated by the general public because they work without pay and altruistically provide free access to subtitled audiovisual contents that are otherwise unavailable. On the other hand, they distribute unlicensed contents and violate the copyright law in China. Their practices cause damages to copyright holders and thus call for legal actions. Given the conflicting moral and legal statuses, it is necessary to understand how the Chinese press frame and represent fansubbers, as the media play a crucial role in shaping people’s opinions. Drawing on a one-million-word corpus of news reports between 2006 and 2018, this study examines the media frames, discourse topics, and representations about fansubbers in China. Based on keyword, collocation, and concordance analyses, four discourse topics were identified: sharing, volunteerism, copyright, and commercialization. The former two pointed to a moral frame, while the latter two fed into a legal frame. The diachronic analysis demonstrated that the topic of sharing was most prominent in eight of 13 years, while the topic of copyright spiked about every five years. The corpus findings also unravel the complexities of discursive strategies in two aspects: (a) representational strategies work in combination to selectively frame fansubbers and (b) the same discursive strategies can simultaneously moralize and delegitimize fansubbers. This study sheds light on the multifaceted, dynamic, and complex nature of media representations about fansubbers with a conflicting social position.

Design and Fabrication of 5 Ton Hydraulic Press Machine

A hydraulic press is a machine using a hydraulic cylinder to generate a compressive force. Frame, hydraulic cylinder and press table are the main components of the hydraulic press. In this project press frame, cylinder and press table are designed by the design procedure. They are analyzed to improve their performance and quality for press working operation. Using the optimum resources possible in designing the hydraulic press components can effect reduction in the cost by optimizing the weight of material utilized for building the structure. An attempt has been made in this direction to reduce the volume of material. So in this paper we consider an industrial application project consisting of mass minimization of H frame type hydraulic press. This press has to compensate the forces acting on the working plates and has to fulfill certain critical constraints. Here we use implementation for analysis and optimization of hydraulic press. The aim of this paper is to integrate the mechanical system of hydraulic press with hydraulic system to facilitate the ease of operation to manufacture the smaller parts in a bulk. In the present scenario, time constrain is a crucial part for completion of any production process. Thus with the aid of automization, the production time can be reduced as well as higher degree of accuracy can be achieved as the human efforts will be alleviated. Thus an attempt has been made to provide the smooth and rapid functioning of press work with the help of hydraulic system.

Study on Optimization of Mining Pillar in Isolated Island Working Face of Thick Coal Seam under Complex Conditions

In this paper, a thick coal seam in Shandong Province is used as a prototype, which is located below the upper layer of 6 m residual pillar, and is a typical isolated island coal face based on the mining theory of upper liberation layer. The optimization study on the coal pillar of the island coal pillar working face formed by the ower stratification is carried out. When mining the coal face with stratified island pillar, it is easy to be affected by the upper residual coal pillar and the lateral support stress of the two side goaf. The isolated island surface is easy to form high concentration stress, the roof movement is violent, the impact ground pressure is easy to be induced, and the support press frame is easy to be formed. Mining earthquake and other dynamic disasters seriously threaten the safety of working face. Therefore, the reasonable determination of the width of coal pillar is guaranteed. By using UDEC numerical simulation method, this paper studies the mining optimization of the coal face under the influence of the upper stratified residual pillar, which is the important factor of the safe mining of the separated island working face under the thick coal seam, and the optimization of the mining of the coal face under the influence of the upper stratified residual pillar. This paper analyzes the stress distribution and evolution law of coal pillar in lower layer protecting roadway, and determines that it is appropriate to keep 12 m coal pillar in isolated island working face of lower stratified coal pillar, and the internal dislocation is 6 m in the residual pillar of upper stratification, which can reduce its impact risk at this time. It can ensure the safe mining and high recovery rate of coal.

The Effect of Cooling Circuits in a Press Frame on the Resulting Accuracy

The constantly increasing demands on product quality place higher requirements on production machines. The machine we investigated is a hydraulic press. Higher accuracy is required and measured on the clamping plates for the tool or on the press frame. The effect of additional cooling in the frame is investigated on a hydraulic press which is intended for production in an industrial production line. The shaping phase of fabric car parts takes place in the mould of this press. The press mould is heated for technological reasons and causes heating of the frame. Heating of the frame causes undesired additional deformation. This paper investigates a press design with additional cooling circuits and its influence on the press work accuracy.

A simulation study on the closed-loop control of screw press forgings using the impact energy as control input

Screw presses are energy-restricted forming machines that use rotational energy stored in a flywheel for forming, which is converted into a linear movement by a threaded screw. Screw presses are widely used for forging steel, aluminum and brass. In a direct-driven electrical screw press, a reversible electric motor is mounted directly on the screw and on the press frame above the flywheel. With directly driven screw presses, the blow energy can be exactly dosed from one blow to the next. However, so far no prior work is known which uses the blow energy as a control input in a targeted manner to influence the properties of the forging. The purpose of the present work is to lay the foundations for property control through blow energy dosing during forging on screw presses. Process control becomes increasingly interesting due to ever increasing customer demands and needs for resource-efficient production. A major challenge is the variation of process parameters, e.g. temperature variations in the furnace, during transport or due to inherent uncertainty in the heat transfer to the dies and the environment. If the process conditions are changing the deviations from the planned process trajectory may lead to an insufficient die filling or undesired final properties. Forged parts require high precision considering the part geometry and material properties. During forming two mechanisms in terms of forming temperature take place: heat conduction due to contact with tools and heat dissipation due to plastic deformation. The heat transfer acts as disturbance, the impact energy can be used as control input. In this work, investigations into process control by impact energy dosing are put forward using FE (finite element) simulations.

Machine Learning Method in Medical Education: Focusing on Research Case of Press Frame on Asbestos

There is a more urgent call for educational methods of machine learning in medical education, and therefore, new approaches of teaching and researching machine learning in medicine are needed. This paper presents a case using machine learning through text analysis. Topic modeling of news articles with the keyword ‘asbestos’ were examined. Two hypotheses were tested using this method, and the process of machine learning of texts is illustrated through this example. Using an automated text analysis method, all the news articles published from January 1, 1990 to November 15, 2016 in South Korea which included ‘asbestos’ in the title and the body were collected by web scraping. Differences in topics were analyzed by structured topic modelling (STM) and compared by press companies and periods. More articles were found in liberal media outlets. Differences were found in the number and types of topics in the articles according to the partisanship and period. STM showed that the conservative press views asbestos as a personal problem, while the progressive press views asbestos as a social problem. A divergence in the perspective for emphasizing the issues of asbestos between the conservative press and progressive press was also found. Social perspective influences the main topics of news stories. Thus, the patients’ uneasiness and pain are not presented by both sources of media. In addition, topics differ between news media sources based on partisanship, and therefore cause divergence in readers’ framing. The method of text analysis and its strengths and weaknesses are explained, and an application for the teaching and researching of machine learning in medical education using the methodology of text analysis is considered. An educational method of machine learning in medical education is urgent for future generations.

A New Approach to Compensate Oscillations of Path-Linked Presses Caused by Inertial Forces

Presses with mechanical linkages based on levers between motor and ram (path-linked presses) tend to oscillate due to inertial forces as a consequence of the drive parts motion.In this publication a new approach for a mass-balancing system is presented. This system allows to generate the optimal compensation forces needed to counteract the inertial forces by means of four linear motors. The control signals for the linear motors are specified by an evolutionary optimization algorithm, which operates on the base of measured accelerations of the press frame. The control signals of the linear motors are created in a way that the machines oscillations are reduced to a minimum. This way the presented mass-balancing system adapts itself automatically to varying conditions during the operation of the machine, such as a tool change or a varying stroke rate.In particular, the present publication provides the results of the conceptual design and the virtual testing of this approach, which has been mainly carried out with the help of multiple-body simulations.

Finite element analysis and topology optimization of a 12000KN fine blanking press frame

Fine blanking press frame is one of the core components of the fine blanking press. Good performance of the frame is of great importance to ensure blanking precision. Simultaneously, lightweight of...

Ending Decades of Animosity: Framing 2014 Thaw in US-Cuba Diplomatic Relations in the Washington Post and Miami Herald

On December 17, 2014, US President Barak Obama and Cuban President Raul Castro simultaneously announced from Washington and Havana that their countries would resume diplomatic relations ended half a century ago. But how did the US press frame the detente? Exploratory and comparative in nature, the study mainly and inclusively examinesvia qualitative and quantitative analysis-the US press’s coverage of the restoration of US-Cuba diplomatic relations. It seeks out the themes in newspaper opinion items in the Miami Herald and The Washington Post to explain the American public’s position and interpretation of Obama’s new Cuba policy.

Design, Fabrication, and Experimental Validation of a Warm Hydroforming Test System

In this study, a hydroforming system was designed, built, and experimentally validated to perform lab-scale warm hydromechanical deep drawing (WHDD) tests and small-scale industrial production with all necessary heating, cooling, control and sealing systems. This manuscript describes the detailed design and fabrication stages of a warm hydroforming test and production system for the first time. In addition, performance of each subsystem is validated through repeated production and/or test runs as well as through part quality measurements. The sealing at high temperatures, the proper insulation and isolation of the press frame from the tooling and synchronized control had to be overcome. Furthermore, in the designed system, the flange area can be heated up to 400 °C using induction heaters in the die and blank holders (BH), whereas the punch can be cooled down to temperatures of around 10 °C. Validation and performance tests were performed to characterize the capacity and limits of the system. As a result of these tests, the fluid pressure, the blank holder force (BHF), the punch position and speed were fine-tuned independent of each other and the desired temperature distribution on the sheet metal was obtained by the heating and cooling systems. Thus, an expanded optimal process window was obtained to enable all or either of increased production/test speed, reduced energy usage and time. Consequently, this study is expected to provide other researchers and manufacturers with a set of design and process guidelines to develop similar systems.