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Article
Publication date: 1 June 2003

B.S. Yilbas, B.J. Abdul Aleem and S. Zainullabdeen

Metal forming through punching finds wide interest in industry. The punch life and the end product quality depend on the punch and workpiece properties as well as punching

Abstract

Metal forming through punching finds wide interest in industry. The punch life and the end product quality depend on the punch and workpiece properties as well as punching conditions. Recently, TiN coating of the punch surface has reported to improve considerably the tool life and the end product quality. This is because of the high hardness and low friction coefficient of TiN coating. In the present study, the wear properties of sheared edges punch is investigated through SEM micrograph and EDS analysis. Mild steel is selected as workpiece material while the punch material is cold‐work tool steel (A2). The punch surface is coated with TiN (PVD) and an uniform coat thickness is assured. It is found that the wear mechanism is governed by adhesive and abrasive wear through shearing. The TiN coating protects the punch surface in the initial cycles of the punching process. As the punching cycle progresses, local defects in TiN coating are observed, i.e. coating is locally worn away.

Details

Industrial Lubrication and Tribology, vol. 55 no. 3
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 1 January 1954

EUGENE GARFIELD

The uses of punched‐cards in documentation are already so varied as to confuse the potential user. Consequently, many organizations and individuals who could efficiently employ…

Abstract

The uses of punched‐cards in documentation are already so varied as to confuse the potential user. Consequently, many organizations and individuals who could efficiently employ existing techniques are not aware of these possibilities. Even in the specialized problem of preparing subject‐heading lists various approaches are in use. The purpose of this paper is to outline the uses of punched‐cards in this special area.

Details

Journal of Documentation, vol. 10 no. 1
Type: Research Article
ISSN: 0022-0418

Article
Publication date: 1 March 1981

G.W. Rippington and J.B. Holmes

In laminate specifications, attention is rarely paid to punching requirements. Although printed circuit manufacturers often assess the punchability of laminates in situ by trial…

Abstract

In laminate specifications, attention is rarely paid to punching requirements. Although printed circuit manufacturers often assess the punchability of laminates in situ by trial and error, there is an increasing need for the laminate manufacturer to have access to laboratory punching tests in order to conform with quality control requirements and keep abreast of current demands on laminate properties. Several national specifications refer to existing punching tests of varying efficacity, a selection of which are discussed. The success of in‐house punching tests is analysed. The EXCELL tool has proved its value in the assessment of blanking and laddering, and two versions of a specially designed piercing tool have been devised to contend with large quantities of small holes. Laboratory investigations have been carried out into the measurement of the forces required for punching, with a variety of laminates, temperatures and punch/die clearances. Penetration/withdrawal force ratios have also been studied in detail. It now remains to research into the area of hole blocking during piercing.

Details

Circuit World, vol. 7 no. 4
Type: Research Article
ISSN: 0305-6120

Article
Publication date: 5 September 2022

Changgeng Zhang, Lan Yang and Yongjian Li

The purpose of this study is to investigate the effect of punching on the local magnetic properties of the nonoriented electrical steel sheet.

Abstract

Purpose

The purpose of this study is to investigate the effect of punching on the local magnetic properties of the nonoriented electrical steel sheet.

Design/methodology/approach

A microcomposite B–H sensor consisting of a pair of B probes with a spacing of 2 mm and a 1.8 × 1.8 mm2 H coil is designed. The region and degree of local magnetic properties degradation caused by punching can be quantitatively analyzed by flexibly moving the composite B–H sensor. The influence and physical mechanism of punching on the hysteresis loss, eddy current loss and excess loss are analyzed based on the Bertotti loss separation theory.

Findings

This study investigates the deterioration effect of the punched nonoriented electrical steel. The permeability near the edge decreases, and the core loss as well as the microhardness increases. The region of magnetic property deterioration is dependent on the area of work hardening.

Originality/value

The microcomposite B–H sensor can be used to measure the magnetic properties near the edge of electrical steel sheets under different processing conditions. This study provides the possibility of precise magnetic property model of the motor core after punching, especially valuable for motors without annealing process.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 42 no. 1
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 June 2001

Eugenija Strazdiene and Matas Gutauskas

The goal of this research work was experimental investigation and evaluation of biaxial punch deformation processes of anisotropic textile materials. The investigation was aimed…

Abstract

The goal of this research work was experimental investigation and evaluation of biaxial punch deformation processes of anisotropic textile materials. The investigation was aimed to solving the following problems: tofind a new criterion for textile behaviour evaluation in punch loading; to evaluate theeffect of material anisotropy for the geometry offormed shell; to determine the straindistribution in anisotropic shell. The experimental data of X‐ray diffraction analysis showed that friction at specimen/punch contact, which earlier was ignored, has a significant effect upon the parameters of the punching process.

Details

International Journal of Clothing Science and Technology, vol. 13 no. 3/4
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 29 April 2021

Donia Salman, Rabab Allouzi and Nasim Shatarat

The main goal is to investigate the effect of size and location of opening and column size on the punching shear strength. Openings are often needed in order to install mechanical…

Abstract

Purpose

The main goal is to investigate the effect of size and location of opening and column size on the punching shear strength. Openings are often needed in order to install mechanical and electrical services. This process takes away part of the concrete volume which is responsible for resisting the shear forces and any unbalanced moment. Furthermore, the application of rectangular columns in flat slabs is commonly used in practice as they provide lateral stiffness to the building. They are also utilised in garages and multi-storey buildings where these elongated cross-sectional columns reduce the effective span length between adjacent columns.

Design/methodology/approach

This research is a numerical-based investigation that is calibrated based on a thirteen previously tested and numerically calibrated slab specimens with no openings. A parametric study is conducted in this study to consider the effect of other parameters, which are the size and location of opening and the rectangularity ratio of column in order to evaluate their effect on the punching shear capacity. A total of 156 models are developed to study these factors. Additionally, the predicted shear carrying capacity of the simulated slabs is calculated using the ACI318–19 and Eurocode (EC2-04) equation.

Findings

The presence of openings reduced the punching shear capacity. The small opening's location and orientation have almost no effect except for one slab. For slabs of large openings, the presence of openings reduced the punching capacity. The punching capacity is higher when the openings are farther from the column. The numerically obtained results of slabs with rectangular columns show lower punching capacity compared to slabs of squared columns with the same length of the punching shear control perimeter. The punching capacity for all slabs is predicted by ACI318–19 and Eurocode (EC2-04) and it is found that Eurocode (EC2-04) provided a closer estimation.

Originality/value

The slabs considered for calibration were reinforced with four different punching shear reinforcement configurations, namely; ordinary closed rectangular stirrups, rectangular spiral stirrups, advanced rectangular spiral stirrups and circular spiral. Generally, there has been limited research on concrete flat slabs with openings in comparison with other subjects related to structural engineering (Guan, 2009) and no research on punching shear with openings of slabs reinforced with these reinforcement schemes. The available research focussed on the effects of openings on the flexural behaviour of reinforced concrete slabs includes Casadei et al. (2003), Banu et al. (2012) and Elsayed et al. (2009). In addition, experimental tests that examined slabs supported on rectangular columns are very limited.

Details

International Journal of Structural Integrity, vol. 12 no. 4
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 1 March 1975

J.L. JOLLEY

I first met punched feature cards in 1956. I was working as an assistant to E. G. Brisch, whose company classified the materials and components used in industry. His method…

Abstract

I first met punched feature cards in 1956. I was working as an assistant to E. G. Brisch, whose company classified the materials and components used in industry. His method brought similar articles together, both notionally in classified codebooks and practically when the classified items were stored in their code number order. The result was an excellent aid to variety reduction, standardization, and stock control. E. G. gave me a good grounding in analytical classification; but his office held other secrets too. One of these was a sort of punched card representing a property or quality, not an object or event as with all other punched cards I had met. On these other cards, notched or slotted for hand‐sorting with needles, or punched and verified in thousands for reading by machine, the holes stood for characteristics possessed by the item concerned. The new cards were different. Since they represented properties, the items possessing these had to be shown by the holes, and so they were. E. G. named them ‘Brisch‐a‐boo’: this I found was his special variant of ‘peek‐a‐boo’, a title by which they are still occasionally known. To stack some of them in exact register with each other is to find, as a set of through holes in numbered positions, the reference numbers of all the items recorded on them which have the qualities concerned.

Details

Journal of Documentation, vol. 31 no. 3
Type: Research Article
ISSN: 0022-0418

Article
Publication date: 13 October 2023

Ying Ying Feng, Yue Jia, Xiao Qian Sun, Guo Peng Chen and Zong An Luo

A new backward punch shape was designed and used in the hydroforming process of double-layer Y-shaped tubes to achieve uniform wall thickness. This study focuses on the…

Abstract

Purpose

A new backward punch shape was designed and used in the hydroforming process of double-layer Y-shaped tubes to achieve uniform wall thickness. This study focuses on the implementation and effectiveness of this novel punch shape.

Design/methodology/approach

A numerical simulation and experimental validation of the hydroforming process of double-layer Y-shaped tubes under various backward punch, replenishment ratios (left and right feed ratios) and internal pressure loading paths was performed using finite elements. During the hydroforming process, an analysis was made on the distribution of stress, strain and wall thickness in both the inner and outer layers of the Y-shaped conduit.

Findings

The novel backward punch parallel to the main tube has been found to improve the distribution of wall thickness in Y-shaped tubes. By controlling the feeding ratio and modifying the loading path of the internal pressure, it is possible to obtain the optimal forming part of the double-layer Y-shaped tube. The comparison between the simulation and experimental results of the double-layer Y-shaped tube formed under the optimal path indicates that the error is within 5% and the distribution of wall thickness is consistent.

Originality/value

A novel backward punch technique is employed to control the hydroforming process in a Y-shaped tube. A study on hydroforming of double-layer Y-shaped tubes with asymmetric features and challenging forming conditions is being suggested.

Details

International Journal of Structural Integrity, vol. 14 no. 6
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 1 February 1972

R.H. Searle and L. Corbett

An IBM 029 card punch is used daily to prepare transaction cards, based on master cards for books and borrowers, which form the computer input to update and process the library…

Abstract

An IBM 029 card punch is used daily to prepare transaction cards, based on master cards for books and borrowers, which form the computer input to update and process the library loans files on disk once each fortnight. The system handles over 100 new loans and renewals each day, giving an annual total of some 25,000 transactions. Output from the computer includes addressed overdue book reminders and various lists. Overall running costs average £120 per month with the cost of a single loan transaction 6p. The same system also controls reports loans. A computer‐based loans control system has been operating at Aldermaston since 1965 when a punched card system, designed for use with an IBM 1460 computer was introduced to replace a four‐part continuous stationary system which had become ineffective through overloading and staff shortage. This, the first computer‐based loans control system to become operational in the United Kingdom, was adapted from one used at the General Electric Company's nuclear establishment at Hanford. The system continued to operate on our next computer, an IBM 360/40 using the ‘1460 emulation mode’, but with the loss of this feature in 1969 when an IBM 360/50 computer was installed it was necessary to reprogram. The time available in which to reprogram was limited by the computer changeover date to only a few weeks. In view of this, and our ultimate aim of fully integrated loans and catalogue records with on‐line access which will require a completely new system, it was decided to make only essential changes and modifications to the existing system. The resulting system (Fig. 1) while basically similar to its predecessor in outline is more sophisticated in detail. The library serves a potential 2,000 customers and has two distinct and separate service points: the Reading Room with a collection of over 26,000 books and pamphlets, of which approximately 7,000 are on loan at any one time, and the Reports Library which has over 230,000 microfiches and microcards and a further 46,000 paper copy reports. The loans control requirements for both departments are similar but not identical. Reports are on closed access, are less used individually than books, have complex serial number references and some are security classified with inherent receipting requirements. One set of program routines processes the loans records of both sections,but on alternate weeks, giving a fortnightly update to each department. A brief tabular outline of the system has already been published in Program. In this paper the description concentrates on the book loans procedures with only a summary of the reports procedures where the differences are substantial.

Details

Program, vol. 6 no. 2
Type: Research Article
ISSN: 0033-0337

Article
Publication date: 1 March 1960

JOHN DAVIES

The new industrial revolution in automation is being paralleled by a revolution in administration. One of the chief tools in this revolution is the punched card and today I am…

Abstract

The new industrial revolution in automation is being paralleled by a revolution in administration. One of the chief tools in this revolution is the punched card and today I am going to outline some of its uses in libraries in industry and in public libraries.

Details

Aslib Proceedings, vol. 12 no. 3
Type: Research Article
ISSN: 0001-253X

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