Method and apparatus of freezing a plug in a pipe for pressure testing

Abstract

Abstract A method and apparatus for freezing a plug in a pipe to provide a closure for pressure testing the pipe, consisting of positioning a heat exchanger about the pipe, and closing off a section of the pipe inside the heat exchanger to prevent thermal circulation of fluid in the pipe outwardly of the area enclosed by the heat exchanger, to thereby lower the freezing time of the ice plug and assure more uniform freezing thereof. Isolation of the area within the heat exchanger can be accomplished by positioning sealing devices at each end of the area to block the flow of convection currents. Such sealing devices may consist of bodies moved through the pipe having sealing elements thereon in wiping engagement with the pipe, or inflatable sealing members which may be placed in the pipe and then inflated to provide sealing engagement with the wall of the pipe. The flanged bodies may be moved through the pipe by hydraulic pressure, and means is provided for moving, detecting and stopping said bodies at the correct location within or adjacent to the freezing area in the heat exchanger. Such means comprises brakes in the body actuated by ultrasonic frequencies from exteriorally of the pipe and a valve closing a central passage therethrough which may be closed or opened by ultrasonic frequencies from exteriorally of the pipe to permit flow through said bodies after being positioned in place and to close same to allow same to be moved through the pipe by hydromatic pressure and to isolate the area within the freezing zone in the heat exchanger.

Inventors

• 👤 Leon E Brooks
• 👤 James T White

Bibliographic Details