Programme details

3D modeling photogrammetry technology uses high-quality digital still images to construct geometrically accurate 3D models suitable for detailed measurements, Finite Element Analysis, 3D printing, and comparison to as-built components. Model manipulation, and construction of interior geometry can also be performed to generate alternative configurations if needed. Photographs are collected either subsea or topside, and pixels are matched between overlapping images to produce a 3D point cloud representing the component geometry. The point cloud is refined using the least squares method to achieve a model accuracy of better than 1mm under ideal conditions. Resulting models can be exported in a variety of formats that are compatible with 3D drafting or finite element analysis software packages. Image overlay can be applied to the models to better identify points-of-interest. Welaptega has used this technology for a variety of applications, including: Riser corrosion: the surface of a topside section of a heavily corroded riser was 3D modeled to determine corrosion depth and evaluate the riser’s fitness for operation. Flange alignment : Leaking mating pipe flanges were 3D modeled to determine if misalignment was the source of the leak. The relative orientations of the flanges were determined by aligning a plane with each flange. Pipeline curvature analysis: An18-inch natural gas pipeline was impacted and dragged by an anchor, resulting in a dent and an unknown degree of curvature. A 3D model of the section of pipe surrounding the point of impact was constructed to determine the radius of curvature and perform finite element analysis. FlexJoint inspection: 3D models were constructed of FlexJoints in support of a regular inspection program. Points-of-interest and signs of wear were identified, measured, and monitored for progression using the 3D models. Wellhead repair: A wellhead was damaged when impacted by a falling Blow-out Preventer during recovery operations. A 3D model was constructed of the wellhead, and imported into design software for comparison to as-built drawings. The 3D model was also used to design a bespoke Internal Tree Cap hold-down tool to ensure well integrity. In all cases, the 3D models provided critical information about component conditions, enhancing clients’ abilities to make decisions regarding repair.