In order to achieve integrated condition in the girth welding of high pressure natural gas transmission pipelines, the weld zones and its surrounding area should have good mechanical properties. Residual stresses are an important defect especially in the girth welding of the pipeline. In this study, two API X70 steel pipes (with spiral seam weld) of 56 inches outside diameter and 0.780 inch wal...

In this paper, a fiber Bragg grating (FBG)-based stress monitoring system instrumented on an orthotropic steel deck arch bridge is demonstrated. The FBG sensors are installed at two types of critical fatigue-prone welded joints to measure the strain and temperature signals. A total of 64 FBG sensors are deployed around the rib-to-deck and rib-to-diagram areas at the mid-span and quarter-span of...

During the weld defect detection, the heat transfer characteristics are closely related to the material properties of welded structure. Based on the electromagnetic induction infrared thermography technology, the heat transfer Characteristics of the welded material are studied with the changing temperature. By using the finite element analysis software COMSOL, the eddy current density and tempe...

An application of machine vision applied to the analysis of radioscopic images of incomplete weld geometries is described. The rationale of the work is to identify weld defects as soon as they are produced, thereby reducing the costs of any subsequent repairs. Existing methods of weld and defect identification are compared, leading to the development of filtering and 'window' based variance ope...

Tubular products in pipe mills are produced by different methods in wide range of sizes and materials for various applications . From simple ERW steel tubes to high quality and expensive seamless tubes, depending on the application, different NDT techniques are used extensively. All these tests are implemented to fulfil the required specification or standard as well as for condition monitoring ...

Libya is an important oil country particularly to European countries. The combustion products of fossil fuels are causing great damage through pollution, acid rains and the greenhouse effect. Hydrogen can be stored in three different ways, as a gas, as liquid, as a material and metal hydrides. Low alloy steels have been widely used in different scale welded structures. The mechanical properties...