Efficient Tube Removal For Air-Cooled Exchangers
Tube removal is a common challenge regardless of the application. In air cooled exchangers, the layout of the tubes, as well as the outer diameter of the fins, could pose some challenges if using traditional methods. However, there are a few tips to make this process quicker.
Complete Retube
A complete retube is often the preferred method for air cooled exchangers due to the design.
- Remove The Top Cover: Access the exchanger’s interior by removing the top cover.
- Cut Behind The Tube Sheet: Cut the tubes behind the tube sheet, before the finned section begins.
- Remove Tube Sections: Carefully lower or lift the cut tube sections from the exchanger.
- Pull Tube Stubs: Use a collet-style tube puller to extract the remaining tube stubs from the back side of the header. This minimizes the risk of damaging the plug hole threads or spot face.
Partial Retube
A partial retube may be required due to plugging or efficiency concerns. However, it can be more complex, especially in multi-row exchangers.
- Remove Tubes Above Affected Area: To access the plugged or damaged tubes, remove the tubes directly above them, if not in the top row.
- Extract Finned Tube Section: Carefully life the finned section of the affected tubes from the exchanger.
- Punch Out Stubs: Use a long-reach knockout tool to remove the tube stubs from the tube sheet. Exercise caution to avoid damaging the header box or plug holes.
Overall, tube removal in air cooled exchangers is a critical maintenance task that requires careful planning and execution. By following the steps outlines above and considering the specific factors involved, you can minimize downtime, ensuring optimal exchanger performance.
