Studying the influence of the interpass temperature on the heat-affected zone of an API 5L X65 steel welded pipe joint through computational and physical simulations

The overwhelming bulk of oil and gas in pipeline construction is done by welding the individual joints of pipe together. In a broad sense, welding is a metal-joining process wherein coalescence is produced by heating to a suitable temperature. In pipeline construction, this temperature has to be sufficient to render fusion of the joint. The mechanical and metallurgical properties and distortions usually present in weld structures are strongly influenced by preheating and interpass temperatures that are applied during the welding process. Basically, interpass temperatures depend on two factors: composition of the material and cooling rate. It is very important to choose the correct interpass temperatures, however, this is not a completely dominating matter. The objective of this paper is to present a study on the effect of different interpass temperatures on morphology, microstructure and consequently on microhardness of welded API 5L X65 steel. The welds were deposited by a Flux Cored Arc Welding Process and the heat input was held constant during all welding production. The interpass temperatures were calculated by different methods. Such temperatures were later verified experimentally. Temperature data were collected via a data acquisition system. The geometry and microstructure characterizations were performed via light optical microscopy and image analysis. These data were related to the different thermal cycles obtained. The results showed that the morphology, the microstructure and the microhardness of welded API 5L X65 steel were strongly influenced by the interpass temperature, revealing how important it is to choose the appropriate value.

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The relationship of crack resistance and structure of a heat-affected zone of welded pipe joints

SCIENCE & TECHNOLOGIES OIL AND OIL PRODUCTS PIPELINE TRANSPORTATION ◽

10.28999/2541-9595-2018-8-2-154-160 ◽

2018 ◽

Vol 8 (2) ◽

pp. 154-160

Author(s):

Svetlana N. Zueva ◽

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Sergey V. Soya ◽

Olga A. Zadubrovskaya ◽

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...

Keyword(s):

Crack Resistance ◽

Heat Affected Zone ◽

Pipe Joints ◽

Welded Pipe ◽

Relationship Of ◽

The Relationship

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Impedance Spectroscopy Studies on Corrosion Inhibition Behavior of Synthesized N,N’-bis(2,4-dihydroxyhydroxybenzaldehyde)-1,3-Propandiimine for API-5L-X65 Steel in HCl Solution

Journal of Electrochemical Science and Technology ◽

10.33961/jecst.2016.7.2.153 ◽

2016 ◽

Vol 7 (2) ◽

pp. 153-160 ◽

Cited By ~ 4

Author(s):

I. Danaee ◽

N. Bahramipanah ◽

S. Moradi ◽

S. Nikmanesh

Keyword(s):

Impedance Spectroscopy ◽

Corrosion Inhibition ◽

X65 Steel ◽

Spectroscopy Studies ◽

Api 5L X65 Steel ◽

Hcl Solution

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Computer Optimizing of Bevel Angles for Welded Pipe Joints

Journal of Ship Production ◽

10.5957/jsp.1986.2.1.18 ◽

1986 ◽

Vol 2 (01) ◽

pp. 18-22 ◽

Cited By ~ 1

Author(s):

H. W. Mergler

Keyword(s):

Direct Relationship ◽

Considerable Reduction ◽

Pipe Joints ◽

Welded Pipe ◽

Weld Area ◽

Pipe Joint

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.

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Numerical Simulation of Steel Lap Welded Pipe Joint Behavior in Seismic Conditions

Pipelines 2018 ◽

10.1061/9780784481646.046 ◽

2018 ◽

Cited By ~ 3

Author(s):

Giannoula Chatzopoulou ◽

Dimitris Fappas ◽

Spyros A. Karamanos ◽

Brent D. Keil ◽

Richard D. Mielke

Keyword(s):

Numerical Simulation ◽

Welded Pipe ◽

Joint Behavior ◽

Pipe Joint

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Calibration of the AC Potential Dropping System (ACPD) for Determination of Crack Growth in API 5L X65 Steel under Cathodic Protection Effect

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1012.412 ◽

2020 ◽

Vol 1012 ◽

pp. 412-417

Author(s):

Misael Souto de Oliveira ◽

Antonio Almeida Silva ◽

Marco Antonio dos Santos ◽

Jorge Antonio Palma Carrasco ◽

João Vitor de Queiroz Marques

Keyword(s):

Crack Growth ◽

Marine Environment ◽

Cathodic Protection ◽

Sea Water ◽

Potential Drop ◽

Mechanical Tests ◽

Flow Density ◽

Type Specimens ◽

X65 Steel ◽

Api 5L X65 Steel

In this work the calibration of an Alternative Current Potential Drop (ACPD) system was performed to monitore laboratory mechanical tests on marine environment under cathodic protection. The calibration was done on CT type specimens of API 5L X65 steel dimensioned according to ASTM E1820 standard., The crack propagation during a tensile test with displacement control in an ACPD equipment was monitored through the performs points collection by two channels: one that monitors the crack growth and another that monitors a region free of crack. Using a profile projector and graphical data processing and analysis software, the area of the fracture surface of the specimen was meansured, which allowed to correlate a crack size with a corresponding value of potential drop and the calibration curve. In order to verify verify the efficacy and precision of the technique, step loading tests were performed on API 5L X65 steel test specimens, submerged in synthetic sea water under the overprotection potential of-1300mVAg/AgCl. The results of the calibration showed few dispersed errors, and the main factors of this dispersion may be related to the geometry of the specimen and with variations in current flow density, which is influenced by corners and edges and by the presence of pick-up inductive. The calibration and its effectiveness can be verified through the results of the tests in marine environment, presenting crack lengths close to the actual values, confirming the effectiveness of the ACPD technique.

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