Abstract: A flexible vibration stabilizer and method for reducing vibration in a tube in a shell and tube heat exchanger wherein the stabilizer is an elongated flexible cable or chain which may have a plurality of rigid members loosely or fixedly mounted thereon. A plug may be used for simultaneously mounting the stabilizer to the tube and for sealing same.

Abstract: The tube plug comprises a shell having a tapered inner surface against which an externally tapered expander member moves by application of a pulling force. The motion of the expander member relative to the shell causes the shell to expand into contact with a heat exchange tube thereby plugging the tube. The expander member is formed from a hardened metal with tangentially blended leading radius and a self-locking trailing edge which provides for ease in expanding the shell while preventing inadvertent unlocking of the plug. The shell has a substantially uniform wall thickness throughout the portion of the shell which experiences expansion so that the force necessary to perform the expanding process does not increase beyond the strength limitations of the installation equipment as the expander member is moved through the shell.