The Preventer valve system is connected to a compressor via an air line. The system is operated by opening and closing the rubber insert, by applying air pressure to inflate (close) or deflate (open) the rubber insert. When the rubber insert is in the closed position, it restricts the entry of the water, whilst pressing tight against the Micropile, allowing the installation and grouting to be completed.
The Preventer is fixed securely to the structure prior to commencing the installation. It is removed once the grout has completely cured, exposing the top of the Micropile ready for the head detail to be constructed.