Method and apparatus for forming a frothed fluid slug for pipe cleaning

摘要

A method and apparatus for forming a low density slug flush for pipe cleaning is set forth. The device includes a container with standpipe which are connected together in the form of a U-tube. A specified liquid volume is held in this. There is a head space in the container at the upper end. The liquid is removed from the container through a bottom located liquid flow line and a top or head connected gas flow line also extends to the line to be cleaned. Remotely, a driving gas is accumulated under pressure and is delivered into the container to force liquid from the container and to also flow through the gas flow line for co-mingling in the line, thereby forming a low density foam which is forced by the continued introduction of gas into the container so that the slug flush travels the full length of the line without jarring the equipment.