US Patent 6854346 Purging system for use with a gas sampling system

A combination purging system and sampling system is provided for sampling gas from a pipeline. A flow path 40 provides fluid communication between a sample bottle 45 and the pipeline. The sample bottle 45 is initially filled with an inert gas for purging air from the flow path 40 and venting to atmosphere. A supply valve 24 controls flow between the pipeline and the flow path 40, and a bleed valve 35 controls venting from the flow path 40 to atmosphere. The relationship and positioning between the valves and the flow path prevents condensation from entering the sampled gas while purging and sampling.