Pigging & Drying
The first step in the pre-commissioning process is to run cleaning pigs through the line to remove construction debris. APS utilizes various types of cleaning pigs equipped with transmitters to clean not only construction debris but also mud, scale, and standing water.
After the de-watering phase is complete the process of pipeline drying can begin. Another series of cleaning pigs and soft foam swabs are sent through the line until all standing water and scale is removed. The line is then dried to the required dew point utilizing oil free compressors and desiccant dryers or nitrogen. Pipeline drying normally specifies a -40° dew point, which is an indication of how much moisture the pipeline will contribute to the flow of gas.