#TITLE_ALTERNATIVE#

• Main Author: HIKMATURRAHMAN (NIM 121 04 007), FIKA
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/12121
• Institution: Institut Teknologi Bandung

Onshore pipe API 5L grade B that is used for transporting crude oil has an upheaval buckling with 50 cm vertical deflection on 20 m pipe segment. The pipe has 8 inch in diameter and 0,313 inch in thick. Pipe temperature increase caused by sun heat after soil cover excavated. Excavating soil cover needed for inspection purpose after there is an forest fire above that buried pipe. Upheaval buckling occurs because of pipe axial force cant be restrained by soil friction force. Upheaval buckling on onshore pipeline influenced by temperature, internal pressure, depth of cover, and imperfection of pipe and soil where pipe placed.<p> <br /> <br /> <br /> <br /> In this study to understand how the effect of each buckling parameter on upheaval buckling phenomena of API 5L grade B pipe, simulation made using analytic methode and finite element methode (FEM). Soil friction force count based on ASME B 31.1. Buckling curve count with assumption of half sinus wave. Kind of deformation determined by counting the elongation (&#916;L) that is difference between length of curve (S’) with buckling length (S). Plastic deformation border taken on 0,002 of strain. Finite element methode (FEM) simulation input is pipe geometry with assumption that pipe length is buckling length (S) and restrained pipe exposed length (L). Soil modeled as spring, hence there are two different model with strain and Von Misses stress as an output. Variation of parameter is : Temperatur increase (&#916;T) 10 degrees C, 20 degrees C, and 40 degrees C, depth of cover (H) 0,5 m, 1 m, 1,5 m, and 2 m, kind of soil (sand and clay), and variation of pipe diameter 8 inch, 10,75 inch, and 12,75 inch.<p> <br /> <br /> <br /> <br /> The result showed that buckling occur on pipeline caused by -246,78 kN axial force bigger than 6 kN of soil friction force. Elongation (&#916;L) of pipe is 0,024 m. Strain value 0,023% &#949; gained for assumption that restrained pipe exposed length (L) and buckling is still on elastic condition. Finite element methode result for strain value is 0,0127% &#949; and buckling is still on elastic condition. Analytic result for assumption that pipe length is buckling length (S) is 0,15% &#949;. Finite element methode result for strain value is 0,33% &#949; it means that pipe is on plastic condition. The biggest axial force gained when &#916;T and pipe diameter used biggest too, the biggest friction force gained when depth of cover and pipe diameter used also the biggest. Sand give friction force bigger than clay.