Development of speed controlled pigging for low pressure pipelines

Abstract

In this study we investigate the development of a speed controlled pig in a low pressure pipeline. This is known to be a challenge due to the compressibility of the gas which can induce velocity surges of the pig. In order to reduce these velocity surges, a speed controlled pig with active by-pass control has been designed, fabricated and subsequently tested on a laboratory scale. The experimental setup consists of a 52 mm diameter pipe with a length of 62 meter. The working fluid is air. The speed controlled pig has an adjustable by-pass valve which can provide the right amount of by-pass to regulate the by-passing fluid force. First test runs show that the velocity surges can indeed be reduced, which demonstrate the feasibility of realizing fully autonomous control for bypass pigs in low pressure pipelines.