Pipe for removing methane from coal seams - with an external elastic seal to fit in a bored hole

摘要

A pipe has a foamed elastic sealing body attached to its outer surface. The pipe is esp. of PVC. The pipe is used to remove methane from coal seams. It is pushed into a hole bored in the coal. The sealing body prevents air leaking along the hole into the pipe inlet. The methane is recovered fredd of air and the safety of the operation is improved.