ABSTRACT
Various construction factors that contribute to pipe failure include improper handling of pipes and physical damage to the pipe or the coating. These factors can affect the performance of the pipeline, especially in metallic and cement-based pipes, as they can lead to contamination and corrosion, the degradation of the pipe wall, and the subsequent failure of the pipeline. Pipes also fail at the joints throughout the pipeline. Improper connection at joints can produce stress concentrations and can lead to the failure of the pipe. The quality of construction of these joints defines the strength of the pipe at their location.
Material properties play an important role in a pipe as the material changes with time. The design strength of a pipe is specified only for a certain time and thus consequently reduces over time. The stress–strain curves also change over time, thus deforming the pipe permanently, i.e. plastic deformation. Consequently, material properties have to be taken into consideration when deciding on a material to use. Improper choice of material could lead to catastrophic failure.
Manufacturing defects also play an important role in the failure of pipes. For example, cast iron pipes that are pit cast have a problem with the wall thickness that can vary around the circumference of the pipe.
Therefore, the chapter gives an overview of the methods of mitigating construction and material defects through an effective quality control program, quality assurance of the pipeline design (e.g. design factor, materials, design criteria), and quality control of pipeline construction.
