The Fast and Safe Way to Seal Leaking Heat Exchanger, Condenser, and Boiler Tubes

  • Rated up to 1000 psi (68.9 Bar)
  • U.S. Patent Number 5,437,310
  • Suitability and type tested by TUV
  • Safer alternative to tapered pins and elastomer plugs
  • Helium leak-tight to 1×10-6 cc/sec

Taper pins can turn into lethal projectiles — and that can pose a real safety hazard for your workers. Now you can eliminate this danger with EST’s Pop-A-Plug® CPI/Perma Plug. Resistant to thermal cycling and able to provide a seal that’s helium-leak tight, EST’s Pop-A-Plug® CPI/Perma Plug installs using controlled force. This protects against damage to tubesheet ligaments and adjacent tubesheet joints, extending the life of your heat exchanger and reducing costs when you need to retube. What’s more, the Pop-A-Plug® CPI/Perma Plug takes only seconds to install. Its broad expansion range fits multiple gauges, so you need to keep fewer plugs on hand — reducing inventory and cutting costs.

The Pop-A-Plug® CPI/Perma Plug is part of a high performance tube plugging system. Tube preparation is the second component. EST removes all tube prep uncertainty by supplying a kit of brushes to cover the Pop-A-Plug® CPI/Perma Plug’s entire expansion range. Other materials are available on a consult factory basis. Ask us about through-the-tube plugging of non-U-tube heat exchangers.


  • Unmatched Performance Under Pressure: Pop-A-Plug® CPI/Perma plugs are conservatively rated for 1,000 psi (68.9 Bar) service.
  • Reliable and Leak Tight: Properly installed, Pop-A-Plug® CPI/Perma plugs stay installed and are helium leak tight to 1×10 -6 cc/sec.
  • Quick Installation Minimizes Downtime: Pop-A-Plug® CPI/Perma plugs are simple mechanical plugs which can be installed hydraulically in minutes without damaging the tube, tubejoint or tubesheet. Installs using standard Pop-A-Plug System Ram Package or Manual Installation Tool.
  • Easy Sizing and Installation: Use PAP Tube Cleaning Brush to prepare the tube end, gauge the tube with a PAP Go / No-Go Gage, select the matching plug size and POP. Pop-A-Plug® CPI/Perma plugs may be removed using the Pop-A-Plug Removal Tool when its time to retube.
  • Broader Expansion Range: Depending on the plug size, individual Pop-A-Plug® CPI/Perma plugs can expand up to .13″ (3.3 mm), reducing the number of plugs sizes required on hand.
  • Materials: Always match Pop-A-Plug® CPI/Perma plugs to the tube material. Pop-A-Plug® CPI/Perma plugs are available for immediate shipment in stainless steel 316, carbon steel and brass. Titanium and other alloys can be supplied by request – Contact factory.
  • Ordering Information: When ordering, specify tube OD and wall thickness or measured tube ID, tube material, tubesheet material if plug will be installed directly into tubesheet, maximum pressure and temperature, type of tube to tubesheet joint (rolled, welded, etc.) and condition of tubes and age of heat exchanger. Specifications subject to change.
  • Quality Assurance System: Manufactured under a Quality Assurance Program certified to ISO 9001 and several U.S. nuclear power industry standards including ANSI N45.2, NQA-1, 10CFR 50 Appendix B, and 10CFR 21.