There is a need for a flexible, insulated jacket that can be used to substantially enclose a pipe junction, then inject a cooling substance into the jacket, and thereby freeze or substantially freeze the contents of the junction. Industries conveying fluids, including fluids such as hydrocarbons, using pipes and valves would benefit from such a jacket. The jacket is shaped to substantially enclose a pipe junction connecting two or more pipes. The jacket includes a flexible insulated body having fasteners. The jacket has an open position and a closed position. The body substantially encloses the pipe junction in the closed position. The jacket further includes at least two fluid injection valves communicated through the jacket body.