| CPC F16L 55/46 (2013.01) [F16L 55/38 (2013.01)] | 30 Claims |

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1. A method of launching a pipeline pig comprising:
said pig having a longitudinal through passage that is arranged to permit a flow of fluid through the pig, the through passage comprising a relatively wide upstream funnel portion that is asymmetrical about a central longitudinal axis of the pig, and a relatively narrow downstream portion; and
a seat for a discrete launching element that, when positioned in the seat, blocks the flow of fluid through the through passage, the launching element being conveyable to the pig entrained in the flow of fluid to engage the pig, wherein the seat is disposed between the relatively wide upstream funnel portion and the relatively narrow downstream portion of the through passage,
wherein the method comprises:
directing a flow of fluid to, and through, the pig being launched;
conveying a launching element to the pig by entraining the launching element in the flow of fluid;
engaging the launching element with the pig being launched; and
by interaction between the launching element and the pig, blocking the flow of fluid through the pig to launch the pig.
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