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A new, easy way to seal leaking tubes!

The Twist & Seal Heat Exchanger Tube Sheet Plug is a solid one piece plug that can be inserted into the tube sheet of a leaking tube and expanded with a standard 3/8" drive torque wrench. The plug will expand approximately 30 mils (.030") to provide a positive mechanical contact seal. The Twist & Seal Heat Exchanger Plug can be used in high or low pressure applications such as feedwater heaters, moisture separator reheaters, preheaters, condensers, coolers, fin-fan coolers or any other tubed heat exchanger.

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• Positive sealing in excess of 6500 PSI is achieved without special tooling or personnel training.
• Plug can be inserted to any depth of the tube sheet in order to avoid severely corroded areas on the tube sheet face.
• Design enables rapid implantation and fit into tight areas adjacent to the tube sheet/shell joint interface, baffle plates and internal dividers.
• One piece design enhances sealing characteristics by eliminating second potential leak path common to design found in two piece plugs.
• Wide sealing area contact zone ensures a positive seal while the gradual and symmetrical torque expansion eliminates thermal and mechanical shock to the tube sheet, commonly found with welding, impact due to hammering of tapered pins, and explosive insertion methods.
• Exclusive design allows installation of plugs at the face and back side of the tube sheet in order to prevent intrusion of shellside corrosives. With single plugging techniques accomplished on the face of the tube sheet, corrosives can enter the void created in the tube sheet, thereby exacerbating erosion and corrosion of the tube sheet ligaments
• Twist & Seal Plugs are available to meet Nuclear ASME Sec. III or ISO 9002 QA specifications.

Twist & Seal ...how it works!
The Twist & Seal plug is snapped onto the hex capture driver and inserted into the tube ID, ensuring that the serrated sealing area is within the tube sheet. Applying the initial torque to the driver engages the anti-spin eccentric cam, locking the plug into the tube ID, thereby providing a torsional resistive force. As additional torque (in. lb.) is exerted, the drive screw threads into the plug body, pressing the tapered expansion ferrule into the reverse taper of the plug. These tapered surfaces combine to generate an enormous radial expansion force, swaging the serrated sealing area into the tube wall. A positive mechanical contact seal in excess of 6,500 psi is created.

Plug Selection Chart

Twist & Seal Hex Drive Capture Systems and Torque Wrench

Installation Instructions
1) A careful measurement of the tube ID should be taken with an inside tube micrometer or a gauging block to determine the actual bore diameter. Select a Twist & Seal Plug that is sized within the range of the measured tube ID. (Example: 0.518" ID tube: use a 148-1510 Twist & Seal Plug.)

2) Clean the tube of any loose scale or corrosive oxide formation. If the tube is out of round, extremely eccentric or cracked, a straight spiral drill reamer should be used to resize the bore of the tube or remove the tube completely.

3) After the correct size Twist & Seal Plug is chosen, affix the plug onto the capture hex driver and insert it into the tube in the tube sheet area of the heat exchanger.

4) Using a ratcheting (in. lb.) torque wrench, begin slowly tightening to the right until you feel the anti-spin eccentric cam lock in place. If the cam does not lock, then the plug is too small for the ID of tube and cannot expand enough for this particular application. After the cam locks it will feel as if there is an even resistance of about 100 in. lbs. Continue applying torque to expand the plug body until you reach the desired torque listed in the chart below.