DESIGN AND CRACK PROPAGATION MODELING WITH EXTENDED FINITE ELEMENT METHOD OF SUBSEA PIPELINE IN MADURA STRAIT

• Main Author: Ardi Ridho, Muhammad
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/68944
• Institution: Institut Teknologi Bandung

Indonesia is a country with a big potential in maritime sector. One of those are the potential for oil and gas. Oil and gas is one of the most frequently used energy sources in Indonesia. It is known that the demand for oil and gas is continues to rose over the year. However, the production of oil and gas in Indonesia its on the decline over recent years. To increase the production of oil and gas, offshore facilities such as subsea pipelines are needed to support the exploration and exploitation process. Subsea pipelines are needed for transporting oil and natural gas from offshore oil wells and gas wells to overland pipelines. Ton of problems are often occurred when the subsea pipeline starts to operate. One of those problems are the integrity of the pipeline being disrupted due to defects found in the subsea pipeline during inspection process. The damage may happen due to crack. To prevent severe damage due to crack, a method called finite element method is carried out, with the intention to check the integrity of cracking pipe. Recently, the extended finite element method, also known as XFEM, is used to model cracks on pipes. Before the pipe is being used, detailed subsea pipeline design must be carried out in order to fulfill the applicable criteria, with pipe wall design criteria using the DNVGL-ST-F101 standard, on-bottom stability analysis using the DNV-RP-F109 standard, installation analysis based on DNVGL-ST-F101, and free span analysis using the DNV-RP-F105 standard. Crack modeling will also be carried out using XFEM, to determined the effect of the crack size that spread from outside of the pipe on a bursting pressure value, due to internal pressure that applied on the model. Based on the design process carried out in this Final Project, the wall thickness of the pipe that will be used is 12.7 mm (0.5 in), the required concrete thickness is 63 mm (2.48 in), and the allowable free span of the pipe is 16.3 m. It is known that the height of the crack size is affecting the burst pressure value the most, due to internal pressure that applied on the model.