Gauging is an economic method to assess the internal profile of a pipeline. We ensure the pipelines are free of all buckles, kinks, and weld over penetration or dents, as we gauge the pipelines internally using a gauging pig. A gauging plate gives only basic information, and it gives no indication of more than one line intrusion or difference between dent and a piece of debris left in the pipeline.
Pipeline will some time require a caliper pig or intelligent depending on the client’s requirements. A Caliper pig measures the pipeline bore as well as the distance travelled, it also indicates the any number of damaged section, whereas a gauging plate only shows single damage.
Process of dewatering is to remove the test water from the pipeline prior to drying. After the hydro test the best dewatering methods leaves a film of water clinging to the inside pipe wall, so therefore, it is necessary to remove this water to eliminate the formations of hydrates and the possibility of the onset of internal corrosion causing carbon dioxide and hydrogen sulfide or to meet the moisture specifications for the delivered product. The pipeline is usually dewatered using a multi -pig train propelled with air. For pipelines that have been filled with seawater, or other non-potable water, the line may also be swabbed with fresh water to remove salt deposits and other contaminants. Several slugs of fresh water be run between pigs at the front of the dewatering train, followed by additional pigs in the dewatering train to ensure maximum bulk water removal.