N.P INSPECTION SERVICES

The NoPig technique realizes a non-destructive testing method for unpiggable pipelines which uses above ground measurements for detecting wall thickness anomalies like corrosion. The method uses an applied current between two points on a pipeline up to 1 km apart. The inspection current contains several harmonic components at distinct frequencies. The resultant magnetic field is measured above ground along the pipe. The measurement data are processed to determine the magnetic field shape. In case of a local pipe wall thinning a frequency-dependent deviation of the magnetic field shape from the circular form occurs. The skin effect and the magnetic stray flux evoke this deviation in case of wall defects caused by corrosion... In the sensor array 6 magnetic sensors are installed in one line. The sensor array consists of four lines with a total of 24 magnetic sensors. Every sensor measures the horizontal component of the magnetic field. The acquisition and storage of collected data will..

Also known as: N.P Inspection Services GmbH