scholarly journals MODELING OF PRESSURE SHAPING DURING MANUFACTURING OF STAMP-WELDED PIPE JOINTS

2018 ◽  
Vol 18 (4) ◽  
pp. 109-120
Author(s):  
K. Torgonin ◽  
◽  
V. Shirokov ◽  
B. Chaplygin ◽  
V. Chernobrovin ◽  
...  
1986 ◽  
Vol 2 (01) ◽  
pp. 18-22 ◽  
Author(s):  
H. W. Mergler

There is a direct relationship between pipe joint welding times and applied weld volume. This paper gives the computations necessary to define the locus for the branch saddle as a function of certain variables and of the optimized bevel angle. Joint configurations were studied for weld area variations for both fixed and optimized bevel angle configurations. Results demonstrated a considerable reduction in weld volume when the optimized volume was compared with the volume obtained using a fixed bevel angle.


Author(s):  
Andrew J. Leonard ◽  
Ronald W. Schutz ◽  
Richard L. Porter

Grade 23 and/or 29 titanium alloy pipe and forgings are typically butt-welded together in the fabrication of offshore riser components such as tapered stress joints (TSJs) for top-tensioned risers and as hang-offs for dynamic catenary risers. Although Grade 29 titanium base metal in a relevant wrought/forged product form has already been evaluated in regards to sustained-load cracking (SLC) resistance, minimal data is available to ensure that the SLC resistance of typical GTA butt-welded joints in these thicker-wall titanium alloy components will also meet design requirements. As part of a TSJ production weld qualification, conservative fracture-mechanics based SLC tests were conducted at room temperature on 1G-position machine GTA butt-welded Grade 23 titanium pipe utilizing Grade 29 titanium filler metal. Test results revealed no significant SLC susceptibility in the weld and a minor effect in HAZ metal, producing KSLC values similar to KQ values. These values safely meet typical TSJ fracture mechanics requirements, and are consistent with published SLC information on this alloy system.


Author(s):  
Houichi Kitano ◽  
Shigetaka Okano ◽  
Masahito Mochizuki

This paper discusses the ultimate tensile strength of girth-welded pipe joints with one or more soft interlayers, as determined by theoretical approaches and FE analysis. In FE analysis, the soft interlayer is assigned to be either the weld metal or heat-affected zone (HAZ). Based on the results of the FE analysis, an evaluation formula is proposed for the ultimate tensile strength of a welded joint including the soft interlayer.


Author(s):  
Wenxing W. Zhou ◽  
Ji Bao

The present study quantifies probabilistic characteristics of the wall thickness of welded pipe joints in onshore gas transmission pipelines based on about 5900 field-measured wall thicknesses collected from a pipeline system in Canada. The collected data cover a wide range of the pipe nominal wall thickness, from 3.18 to 16.67 mm. By considering the measurement error involved in the collected wall thickness data, statistical analyses indicate that the actual-over-nominal wall thickness ratio (AONR) follows a normal distribution with a mean of 1.01 and a coefficient of variation (COV) ranging from 1.6 to 2.2% depending on the nominal pipe wall thickness. The implications of the developed AONR statistics for the reliability analysis of corroded pipe joints are investigated. This study provides key input to the reliability-based design and assessment of pipelines with respect to various threats such as metal-loss corrosion and stress corrosion cracking.


2019 ◽  
Vol 2019 (3) ◽  
pp. 55-63
Author(s):  
P.N. Tkach ◽  
◽  
A.V. Moltasov ◽  
I.G. Tkach ◽  
S.N. Prokopchuk ◽  
...  

Author(s):  
Tetsuo Teramae

A study had been conducted to establish the precise method estimating the creep rupture life of welded steam pipe joints used for thermal power plants. Firstly, basic creep data of 2.25CrlMo low alloy steel, such as rupture time, minimum creep strain rate, and creep crack growth rate, had been obtained on mother material, fine-grained heat affected zone (HAZ), coarse-grained HAZ, and weld metal. Secondly, internally pressurized creep rupture test had been conducted on the pipe specimens of mother material, seam welded joint and girth welded joint. Whereas girth welded pipe joints showed longer lives than those of mother material pipes, seam welded pipe joints showed shorter rupture lives. To clarify the effect of fine-grained HAZ on the rupture life of the seam welded pipe joint, an analytical study had been performed taking the difference of creep deformation between fine-grained HAZ and mother material into account. The analytical creep rupture life had agreed quite well with experimental one. Finally, internally pressurized creep rupture test had been conducted on the specimens of the seam welded pipe joints with a semi-elliptical notch introduced along the outer HAZ of weld line. Creep rupture life of these specimens was calculated as the sum of crack incubation time and crack growth time. It was shown that the calculated creep rupture life had agreed quite well with the experimental result.


2015 ◽  
Vol 763 ◽  
pp. 92-96
Author(s):  
Yuriy Ivanovich Pashkov ◽  
Mikhail Alekhsandrovich Ivanov ◽  
Yuriy Viktorovich Bezgans ◽  
Tatyana Vladimirovna Bezgans

There was performed the analysis of a set of methodical solutions for determining of current and limit plasticity of welded joint zones at large diameter pipes. To determine the current plastic deformation of zones of pipes' welded joints it is offered to test the natural ring of a height of 80 mm, of a pipe with size 530x7,5 mm made of steel 17GS, welded by arc welding using a welding wire SV-08HM under a layer of flux AN-60. The ring samples are tested in the cone, the constructive dimensions of which match the cone used on the expander by the definite value of broadening on the hydraulic press with the force not less than 500 tons. The results of tests of ring samples of welded pipe with size 530х7,5 mm while their broadening by the cone. To determine the limit of plastic deformation of zones of a welded joint of large diameter pipes a method for testing a flat sample is proposed. The construction of the sample and the scheme of loading to determine the limit plasticity of welded pipe joints are proposed.


Sign in / Sign up

Export Citation Format

Share Document