Compression of a plastic layer by two rough plates

Ostsemin, A. A.; Dil'man, V. L.

doi:10.1007/bf00767561

Cited by 7 publications

(10 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…al. [7][8][9] proposed classification of composite joints with various mechanical heterogeneity as well as the equations to assess the strength value of pressure contact welded steels.…”

Section: Introductionmentioning

confidence: 99%

Investigation of the rupture of Ti/Steel laminated composite with soft interlayers

Trykov¹,

Гуревич²,

Pronichev

et al. 2016

FME Transaction

View full text Add to dashboard Cite

“…al. [7][8][9] proposed classification of composite joints with various mechanical heterogeneity as well as the equations to assess the strength value of pressure contact welded steels.…”

Section: Introductionmentioning

confidence: 99%

Investigation of the rupture of Ti/Steel laminated composite with soft interlayers

Trykov¹,

Гуревич²,

Pronichev

et al. 2016

FME Transaction

View full text Add to dashboard Cite

“…The tangential stresses τ xy depend linearly on the plastic layer (X axis in Fig. 1) [8]. The existence of a branch point O 1 in the plastic flow of the soft interlayer is a characteristic feature of the plastic deformation of welded joints with a crack-like defect (see Fig.…”

mentioning

confidence: 99%

“…Here, formula (5) takes on the form (6) for the average failing stresses. It should be pointed out that when there is no defect, l = ∆ = 0 in formula (6) [8]. From formula (6), we can determine the range of relative dimensions of defects for which a welded joint is equal in strength to the defect-free joint:…”

mentioning

confidence: 99%

“…This makes it possible to assess the static strength of these joints by methods of the theory of plasticity [8].…”

mentioning

confidence: 99%

“…Let us examine the stress state and strength of a welded joint with a surface defect located in the soft (weaker) seam on the results of studies [3,8] in which Prandtl formulas [9] for calculation of components of the stress tensor are defined more precisely by approximate solution of a system of equilibrium equations for a finite strip. Figure 1 shows parameters of the soft (S) interlayer with a surface defect in the welded seam -hard (H) interlayer, where h and B are the thickness and length of the plastic layer (welded joint), ∆ and l are the width and length of the crack-like defect, h 1 = h/2, h 2 = ∆/2, and l 2 is the zone of the plastic layer.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Static Strength of Mechanically Nonuniform Welded Joints with a One-Sided Surface Defect Subject to Ductile Failure

Ostsemin

Dil'man

2005

Chem Petrol Eng

Self Cite

View full text Add to dashboard Cite

A new formula is proposed for calculation of the average limiting stress of a welded joint in a thin-wall cylindrical pipe or plate; this formula takes into account the magnitude of mechanical nonuniformity, the dimensions of the softened interlayer, and the depth and width of a surface defect located in the zone of thermal influence of the welded seam. The range of relative depths of a surface defect in a welded joint in pipes, for which the welded joint has a strength equal to the base metal, is determined theoretically.When static loads act on a uniform welded joint formed from metals with a high plasticity, defects of short length and shallow depth will cause a reduction in the strength of the joint approximately proportional to the relative size (or area) of the defect [1, 2]. If the welded joint is mechanically nonuniform, the effect of defects on static strength will be determined by their magnitude and location, as well as by structural-geometric parameters and the degree of the joint's mechanical nonuniformity.Basic causes of defect formation in pipes are poor-quality metal, welding wire, and flux, and imperfection of production, forming, and welding procedures.At the present time, rigid standards (Construction Rule and Regulation 2.05.06-85 "Arterial Pipelines"), which prohibit crack-like defects (lack of penetration, incomplete fusion, undercuts, slag inclusions, cracks, leading-edge extensions, and craters in seams) are established for permissible defects. A considerable volume of repair work is therefore conducted to correct welding defects. These measures cannot be recognized as correct, since experience gained with the service of large-diameters pipes indicates that in the majority of cases, welding defects exceeding existing standards, do not lead to a reduction in the bearing capacity of welded joints in arterial pipelines. Assessment of the service reliability of welded joints in pipes and plates where defects exist, and development of recommendations for determination of degree of risk for crack-like defects assume major practical significance.Various deviations from the assigned procedures, as a result of which the volume of work required to correct welding defects in pipelines increases significantly, however, arise during construction and assembly operations; investigation of the effect of a plane surface defect in the zone of thermal influence (ZTI) of plates and pipes, where plasticity (relative elongation and contraction) reaches a minimum value, is therefore an urgent problem.Dil'man and Ostsemin have investigated the stress state and strength of welded seams in large-diameter straight-and helical-seam pipes with and without defects, and the strength of a mechanically nonuniform welded seam in a pipeline with different defect arrangements in [1-4] and [5], respectively. They present [6] a detailed theoretical analysis of the bearing

show abstract

Stress state and strength of welded joints in large-diameter pipes

Dil'man¹,

Ostemin²

1998

Chem Petrol Eng

View full text Add to dashboard Cite

In 1995, the losses from failures of oil pipelines in the Russian Federation were approximately 280 billion rubles. Consequently, examination of the strength properties of welded joints in large diameter pipes is an urgent and important problem. In this work, we propose a new method of examining the stress state and strength of dissimilar welded joints with the H -S -H (hard -soft-hard) hardness schema for welded joints in large-diameter pipes. The cross section of the longitudinal welded joint in a large diameter pipe can be regarded as a region with two orthogonal axes of symmetry on which the components of the stress tensor are determined. The longitudinal welded joint, interpreted as a ductile layer, is sufficiently large and, consequently, its stressed state can be examined by the methods of solving a statistically determinate planar problem of plasticity theory.We shall examine the threshold state of a mechanically heterogeneous welded joint under tensile loading which determines the load-carrying capacity of the weld under ductile fracture conditions. Usual assumptions [1] and simplifying conditions will be accepted. The medium of the examined section is regarded as ideally rigid-plastic. In the resultant solutions, the parameters of such medium are replaced by the parameters of the strengthened medium, in particular, the shear yield limit kr was replaced by ultimate strength Ice.According to the static definability of the problem, we solved the system of equations of plastic equilibrium in relation to the unknown components of the stress tensor ax (x; y), % (x; y), 7",~ (x; y), given on the cross section of the welded joint by the plane normal to the plane of the pipe. As a result of the large diameter of the pipe, this cross section is assumed to be a rectangle with width L (thickness of the pipe) and height h (thickness of the welded joint). Let it be that k = L/h is the relative thickness of the welded joint.Usually, the available values of the stress tensor at the boundary of the region are insufficient for obtaining an unambiguous solution of the boundary-value problem. In addition to the zero values of the components at the free boundary, only the value of the tangential stress at the line of contact of the plastic layer and the parent metal in the vicinity of the free boundary -the extreme value r~ at the contact line -is usually known (from physical considerations and is included in the problem as a boundary-value condition). In this section, the tangential stress is stabilized in many cases (compression in pressure working of metals [2], tensile loading of the welded joint in the pipe [1]), reaching the highest value

show abstract

Compression of a plastic layer by two rough plates

Cited by 7 publications

References 1 publication

Investigation of the rupture of Ti/Steel laminated composite with soft interlayers

Investigation of the rupture of Ti/Steel laminated composite with soft interlayers

Static Strength of Mechanically Nonuniform Welded Joints with a One-Sided Surface Defect Subject to Ductile Failure

Stress state and strength of welded joints in large-diameter pipes

Contact Info

Product

Resources

About