Pig assembly and method for maintaining a functional line for conveying fluid

摘要

Disclosed is a pig assembly 100 for maintaining a functional line for conveying fluid. In one aspect, the pig assembly 100 includes a larger diameter pig 101 having an internal compartment 112 and at least one smaller diameter pig 110 adapted to fit therein. The larger diameter pig 101 is capable of passing through a larger diameter functional line and the smaller diameter pig 110 is capable of passing through a smaller diameter functional line. In another aspect, a method for maintaining a functional line for conveying fluid is provided which includes pigging a subsea line having at least a larger diameter functional line and a smaller diameter functional line in fluid communication with one another using a pig assembly 100 as described herein.