scholarly journals The amount of heat input to the weld per unit length and per unit volume

2021 ◽  
Vol 1199 (1) ◽  
pp. 012067
Author(s):  
J Winczek ◽  
M Gucwa ◽  
K Makles ◽  
M Mičian ◽  
A Yadav
Keyword(s):  
Comparative Analysis ◽  
Welded Joints ◽  
Heat Input ◽  
Unit Volume ◽  
Unit Length ◽  
Practical Application ◽  
Actual Amount ◽  
Volume Unit ◽  
The Individual ◽  
Volume Method

Abstract This paper presents a comparative analysis of heat input per unit length and per unit volume for selected methods of welding. The purpose of the analysis is to assess the usability of calculating heat input per volume unit. The interpretation of heat input per unit length according to the standards: QW-409.1 of ASME IX, EN ISO 1011-1 is discussed. The concept of calculating heat input per unit volume is described. For exemplary padded welds and spot welded joints, the heat input values were calculated in accordance with the above-mentioned standards and based on the concept of heat input per unit volume. The study showed a lack of consistency between the individual standards in the interpretation of the heat input. In addition, the practical application of the heat input per unit volume method in calculating the actual amount of heat introduced into the weld was justified.

Mutual friction in a heat current in liquid helium II III. Theory of the mutual friction

1957 ◽  
Vol 242 (1231) ◽  
pp. 493-515 ◽  
Keyword(s):  
Friction Force ◽  
Unit Volume ◽  
Unit Length ◽  
Heat Current ◽  
Mutual Friction ◽  
Superfluid Turbulence ◽  
Vortex Lines ◽  
Magnus Effect ◽  
The Individual ◽  
Dimensional Argument

As was shown in part II, the Gorter-Mellink mutual friction force in a heat current is probably associated with turbulence in the superfluid. Following Feynman, it is suggested that this turbulence takes the form of a tangled mass of quantized vortex lines, so that the mutual friction probably arises from collisions between thermal excitations and these vortex lines. From the observed properties of the mutual friction it is deduced that the walls of the channel carrying the heat current play no essential role in the generation, maintenance or decay of the turbulence, but merely introduce a number of incidental complications; the present paper ignores these complications and deals therefore with the idealized case of a homogeneous heat current in an unbounded volume of helium. The turbulence in this idealized case must be homogeneous, and it is shown from experimental evidence that it is probably also isotropic. Values of the force exerted on unit length of a vortex line, which have been derived from the study of the attenuation of second sound in uniformly rotating helium, are used to calculate the Gorter-Mellink force per unit volume in terms of the length of line per unit volume; then by a simple dimensional argument it is shown that the force must depend on (v s — v n ) in a manner agreeing with experiment. An attempt is made to produce a detailed theory of the generation and decay of superfluid turbulence: it is shown first that owing to the Magnus effect the turbulence can probably be built up by the action of the mutual friction force exerted on the individual lines, although the way in which turbulence can be initiated in undisturbed helium is not known, and secondly that the turbulence can probably decay in a manner closely analogous to the decay of homogeneous turbulence in an ordinary fluid. Equations for the rate of generation and decay of turbulence are obtained by dimensional arguments, and by analogy with formulae known to apply to turbulence in an ordinary fluid. Comparison of the equations with the experimental results described in parts I and II reveals good agreement, and makes it possible to deduce the form and magnitude of a term describing the effect of the unknown initiation process.

scholarly journals New method of calculating the amount of heat input to the weld

2020 ◽  
pp. 23-27
Author(s):  
Jerzy Winczek ◽  
Kwiryn Wojsyk
Keyword(s):  
Surface Area ◽  
General Formula ◽  
Fusion Zone ◽  
Heat Input ◽  
Unit Volume ◽  
Welded Joint ◽  
Unit Length ◽  
Welding Process ◽  
Electric Arc ◽  
New Method

A new method of calculating the amount of heat introduced into the welded joint is presented. Instead of the previously used measure of heat input per unit length, heat input per unit volume was proposed. The proposed method and general formula are based on the basic technological parameters of the welding process (i.e. energy generated by the electric arc and welding speed) and the cross-sectional area of the fusion zone in the welded joint. A simplified method of calculating heat input per unit volume is presented by using simple formulas to calculate the surface area of the fusion zone in cross-section of the weld for the most common shapes in classic welding methods. The proposed general formula allows for a more accurate way of calculating the heat input per unit of volume depending on the the energy generated by the electric arc (e.g. for pulse current) and the surface area of the reinforcement and fusion zone using other direct measurement methods.

scholarly journals Effect of Heat Input on LMHMW Joint of Carbon Steel

2021 ◽  
Vol 12 (1) ◽  
pp. 301
Author(s):  
Shujun Zhou ◽  
Tingyan Yan ◽  
Waqas Muneer ◽  
Xuan Yin ◽  
Qiyu Gao ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Carbon Steel ◽  
Welded Joints ◽  
Heat Input ◽  
Optical Microscope ◽  
Transformation Process ◽  
Steel Plates ◽  
Process Efficiency ◽  
Bilateral Effects ◽  
The Individual

Laser-MIG hybrid multi-layer welding (LMHMW) technology has been employed in paraxial configuration with laser leading for the welding of 20 mm thick Q235 carbon steel plates to exploit the hybridization effect that addresses the shortcomings of the individual process as well as to compliment their merits. The bilateral effects of arc augmented laser welding have resulted in complete joint penetration, process efficiency, stability and gap bridge ability. Samples welded under varying heat inputs in multiple passes have been analyzed for their microstructure evaluation using an optical microscope followed by tensile and Vickers hardness testing in various regions of the weld zones. This process was conducted to characterize the effect of heat input on the mechanical properties of the welded joints. The experimental results illustrate that different heat inputs have significant effects on the microstructure, heat affected zone width and mechanical properties of welded joints. The microhardness near the fusion line decreases dramatically due to the influence of the phase transformation process, and the highest microhardness value is obtained in the center of the weld seam. By using reasonable process parameters, the strength of the welded joint can obtain 458.5 MPa.

Formation of Standing Waves in Radial Tires

1984 ◽  
Vol 12 (1) ◽  
pp. 44-63 ◽  
Author(s):  
Y. D. Kwon ◽  
D. C. Prevorsek
Keyword(s):  
High Speed ◽  
Critical Speed ◽  
Unit Length ◽  
Standing Waves ◽  
Rolling Resistance ◽  
Damping Coefficient ◽  
Circular Membrane ◽  
Critical Speeds ◽  
Steel Cord ◽  
The Individual

Abstract Radial tires for automobiles were subjected to high speed rolling under load on a testing wheel to determine the critical speeds at which standing waves started to form. Tires of different makes had significantly different critical speeds. The damping coefficient and mass per unit length of the tire wall were measured and a correlation between these properties and the observed critical speed of standing wave formation was sought through use of a circular membrane model. As expected from the model, desirably high critical speed calls for a high damping coefficient and a low mass per unit length of the tire wall. The damping coefficient is particularly important. Surprisingly, those tire walls that were reinforced with steel cord had higher damping coefficients than did those reinforced with polymeric cord. Although the individual steel filaments are elastic, the interfilament friction is higher in the steel cords than in the polymeric cords. A steel-reinforced tire wall also has a higher density per unit length. The damping coefficient is directly related to the mechanical loss in cyclic deformation and, hence, to the rolling resistance of a tire. The study shows that, in principle, it is more difficult to design a tire that is both fuel-efficient and free from standing waves when steel cord is used than when polymeric cords are used.

Impact of the divorce experience on the marital and family mindsets

2018 ◽  
pp. 88-96
Author(s):  
Елена Лактюхина ◽  
Elena Laktyukhina ◽  
Георгий Антонов ◽  
Georgy Antonov
Keyword(s):  
Comparative Analysis ◽  
Demographic Characteristics ◽  
Representative Sampling ◽  
First Marriage ◽  
Active Population ◽  
Volgograd Region ◽  
The Social ◽  
Marriage Stability ◽  
Main Factors ◽  
The Individual

The article presents a comparative analysis of marital and family mindsets of two categories of the demographically active population of modern Russia: (1) individuals that have no experience of a divorce and (2) those who have already experienced one or more official termination of a marriage. The empirical base of the analysis is the data of the author’s questionnaire survey conducted by representative sampling in Volgograd and Volgograd Region in 2015–2016. The analysis was made on the following basic empiric indicators: optimal (from the viewpoint of the respondents) age for the first marriage, frequency of mentioning marital and family statuses as the respondents describe their own social and demographic “portrait”, legitimate causes of a divorce and a number of others. It is found that, in the case of sufficiently strong traditional marital and family mindsets, perception of marital norms is adjusted, if an “abnormal” event (such as a divorce) occurs in the individual’s life course. At the same time, perception of the marriage stability is less variable and does not depend on the social and demographic characteristics of the respondents, including the presence/absence of a marriage termination experience. The “strongest” factor that affects the change of the marital and family mindsets is age. With age (and, consequently, experience accumulation), importance of the majority of main factors capable of preventing the individual from a divorce decreases and, therefore, the risk of such event increases.

scholarly journals Research on the Relationship between Shared Leadership and Individual Creativity-Qualitative Comparative Analysis on the Basis of Clear Set

2021 ◽  
Vol 13 (10) ◽  
pp. 5445
Author(s):  
Muyun Sun ◽  
Jigan Wang ◽  
Ting Wen
Keyword(s):  
Comparative Analysis ◽  
Environmental Factors ◽  
Shared Leadership ◽  
Management Practices ◽  
Qualitative Comparative Analysis ◽  
Necessary Condition ◽  
The Individual ◽  
The Impact ◽  
The Relationship ◽  
Sufficient And Necessary Condition

Creativity is the key to obtaining and maintaining competitiveness of modern organizations, and it has attracted much attention from academic circles and management practices. Shared leadership is believed to effectively influence team output. However, research on the impact of individual creativity is still in its infancy. This study adopts the qualitative comparative analysis method, taking 1584 individuals as the research objects, underpinned by a questionnaire-based survey. It investigates the influence of the team’s shared leadership network elements and organizational environmental factors on the individual creativity. We have found that there are six combination of conditions of shared leadership and organizational environmental factors constituting sufficient combination of conditions to increase or decrease individual creativity. Moreover, we have noticed that the low network density of shared leadership is a sufficient and necessary condition of reducing individual creativity. Our results also provide management suggestions for practical activities during the team management.

scholarly journals Evaluation of tensile strength and fatigue strength of commercial pure aluminum/tough pitch copper friction-welded joints by deformation heat input

2007 ◽  
Vol 57 (8) ◽  
pp. 357-361 ◽  
Author(s):  
Hiizu OCHI ◽  
Yoshiaki YAMAMOTO ◽  
Takashi YAMAZAKI ◽  
Takeshi SAWAI ◽  
Gosaku KAWAI ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Fatigue Strength ◽  
Welded Joints ◽  
Heat Input ◽  
Pure Aluminum ◽  
Commercial Pure Aluminum

scholarly journals Finding ways to improve the performance of welded joints based on controlled heat input and use of shock-mechanical treatment

2021 ◽  
Vol 1791 (1) ◽  
pp. 012118
Author(s):  
Yu N Saraev ◽  
I S Kamantsev ◽  
A A Grigoryeva ◽  
A V Kuznetsov ◽  
V M Semenchuk ◽  
...  
Keyword(s):  
Welded Joints ◽  
Heat Input ◽  
Mechanical Treatment

Stimulation and limits of cloud-based ITSM system application by Russian companies

2021 ◽  
Vol 19 (10) ◽  
pp. 2001-2010
Author(s):  
Yurii P. KISHKOVICH
Keyword(s):  
Information Systems ◽  
Comparative Analysis ◽  
Financial Performance ◽  
System Application ◽  
Management System ◽  
Business Processes ◽  
Enterprise Management ◽  
Practical Application ◽  
Russian Economy ◽  
Enterprise Management System

Subject. This article discusses the use of information systems in various spheres of the Russian economy. Objectives. The article aims to assess the prospects for the use of cloud-based ITSM systems by Russian medium-sized and large companies. Methods. For the study, I used a comparative analysis. Results. The article finds that the cloud-based ITSM system reduces the time of business processes significantly and saves money resources. Conclusions. The practical application of cloud-based ITSM systems expands the opportunities and capabilities of medium-sized and large enterprises significantly and contributes to improving the financial performance of their activities. The enterprise management system is an important factor the implementation of these systems depends on.

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