This article reports on a numerical and experimental investigation to understand improve computer methods in application of the Goldak model for predicting thermal distribution submerged arc welding (SAW) APIX65 pipeline steel. Accurate prediction cycle residual stresses will enable control fusion zone geometry, microstructure, mechanical properties SAW joint. In this study, new heat source is presented first. Both 2D 3D finite element models are developed using solution transfer equations...

ABSTRACT In this research, mechanical characteristics of double submerged arc‐welded line pipe steel grade API X70 (70 ksi yield strength) were investigated. Different experimental examinations including chemical analysis, microstructural investigation, microhardness, tensile and Charpy tests standard fractography carried out on different zones test material. Impact properties the fusion zone, heat‐affected zone (HAZ) base metal measured an instrumented rig correlated then to their features....

ABSTRACT This paper presents a new data analysis technique to rapidly identify the region of stable crack growth in tip opening angle (CTOA) testing modified double cantilever beam. The basically used load–displacement from CTOA on API X65 steel, which demonstrated constant slope after peak load. In total, 22 points (out 90) fell this region, for variation versus length remained almost constant. measurement was conducted edges and fine reference grid, using photographs two cameras front rear...

Failure information from recent full-scale burst experiments on modern TMCP gas pipeline steels having a yield strength level of 690MPa and higher has shown that the CTOA fracture criterion can be effectively used to predict arrest/propagation behaviour pipe against possible axial ductile fractures. The use as an alternative or addition Charpy V-notch DWTT energy in pipelines is currently under review. A significant difficulty limiting more extensive assessment its practical evaluation...

Recent experimental and computational studies have revealed that the CTOA fracture criterion has potential to assess steady state ductile rupture resistance during large amounts of crack growth. One major difficulties currently limiting more extensive use is its practical estimation either on a real structure or in laboratory scale test. The authors recently developed novel test technique for direct measurement CTOA. It single (SCT) method using modified double cantilever beam (DCB)...

Charpy upper shelf energy is widely used as a fracture controlling parameter to estimate the crack arrest/propagation performance of gas transportation pipeline steels. The measurement this criterion particularly for modern steels and its apportion into different components, i.e. non-related energy, are great importance engineers. This paper presents results instrumented impact experiments on high-grade steel grade X100. First, instrumentation technique including design implementation strain...

In this research, the effect of low velocity impact (LVI) on different components fracture energy API X65 gas pipeline steel is investigated using drop weight tear test (DWTT) specimens. For purpose, twenty one specimens (arranged in seven similar groups) were used. The LVI tests carried out first six groups by releasing machine hammer from heights 0.05 m to 0.3 m. Then, full DWTTs conducted all 2 height. tested and its calculated data an instrumented hammer. These compared energies virgin...

Charpy upper shelf energy is widely used as a fracture controlling parameter to estimate the crack arrest/propagation performance of gas transportation pipeline steels. The measurement this criterion particularly for modern steels and its apportion into different components (i.e. non-related energy) are great importance engineers in order transfer laboratory data from experiment real structure. As conventional impact test has only one output overall instrumented been achieve full failure...

In this paper, energy absorption characteristics of spiral welded gas pipeline steel are investigated under impact loading. Emphasise is given to consuming processes before fracture propagation in tested linepipe steel. The API X65 grade pipe was produced (by Sadid Pipe and Equipment Company) from thermo-mechanical controlled process (TMCP) coils supplied by a Korean mill. To measure material toughness, an instrumented Charpy machine used. Experiments were conducted at room temperature on...

One important pipes inspection step in the pipe mills is determination of out roundness values ends before their shipment to end users. In such pipes, inspecting a significant which ensures appropriate placement edges. This reduces stress concentrations between connection. addition, acceptable this parameter reduce welding and connecting problems considerably. Among methods, non-contact methods have been diversely applied. study, machine vision used as pioneer method for investing factor....

This paper reports recent results from a set of experimental and computational studies ductile flat fracture in modern gas pipeline steel. Experimental data plain notched cylindrical tensile bars standard C(T) specimens together with damage mechanics theories have been used to capture the characteristics steel grade X100. The modelling was via finite element analysis using Gurson-Tvergaard modified model (GTN) development. assumption effective material isotropy sufficiently accurate allow...