Internal Pipe Cutters & Tube Pullers: Heat Exchanger Re-Tubing Tools Guide

1. The Re-Tubing Challenge

Every heat exchanger and boiler eventually reaches a point where its tubes are too corroded, eroded, cracked or damaged to continue in service. When that happens, the old tubes must be removed and new tubes installed — a process called re-tubing. Removing old tubes that are expanded (and often welded) into a tube sheet is a demanding job that requires the right specialist tools: internal pipe cutters and tube pullers.

These tools are the counterpart to tube expanders. Where tube expanders install new tubes, internal pipe cutters and tube pullers remove the old ones — together forming the complete re-tubing toolkit that every heat exchanger and boiler maintenance operation needs.

2. Why Tubes Need to Be Removed

Tubes are removed and replaced when inspection reveals they can no longer safely perform:

• Corrosion: Tube walls thinned by internal or external corrosion below safe limits.
• Erosion: Inlet-end erosion or erosion-corrosion thinning tube walls.
• Leaks and cracks: Perforations or cracks causing cross-contamination between the tube-side and shell-side fluids.
• Under-deposit corrosion: Damage beneath scale deposits, often found after cleaning.
• Fatigue and vibration damage: Cracks from flow-induced vibration, especially at baffles.
• End-of-life re-tubing: Whole-bundle replacement when many tubes reach the end of their service life.

3. Internal Pipe Cutters: How They Work

An internal pipe cutter (internal tube cutter) cuts the tube from the inside, just behind the tube sheet, to sever the tube from the portion that is expanded into the tube sheet. This is the first step in tube removal.

The cutter is inserted into the tube bore and positioned just inside the tube sheet. A cutting wheel or blade is expanded against the tube inner wall, and as the tool rotates, it cuts through the tube wall from the inside. This severs the main tube length from the short stub that remains expanded in the tube sheet — allowing the main tube length to be pulled out and the stub to be collapsed and removed separately.

4. Tube Pullers: How They Work

A tube puller extracts the tube (or tube stub) from the tube sheet by gripping it internally and pulling it out. Several mechanisms are used:

• Spear/spike pullers: A tapered, threaded spike is driven or screwed into the tube end, gripping the inner wall; the tube is then pulled out with a slide hammer or hydraulic puller.
• Collet pullers: An internal collet expands to grip the tube bore, then a hydraulic or mechanical puller extracts the tube.
• Continuous tube pullers: Powered pullers that grip and continuously pull the tube out — fast for full-bundle re-tubing with many tubes.

The choice depends on tube size, how tightly the tube is expanded/welded, and how many tubes must be removed.

5. The Complete Tube Removal Workflow

After removal, the tube sheet holes are cleaned and inspected, then new tubes are inserted and expanded (and welded if required) using tube expanders — completing the re-tubing.

6. Types and Selection

7. Applications

Internal pipe cutters and tube pullers are used wherever heat exchangers and boilers are re-tubed:

• Power plant condensers — full-bundle re-tubing of large condensers with thousands of tubes
• Refinery and petrochemical heat exchangers — replacing corroded process and cooling water exchanger tubes
• Boilers — removing damaged fire-tube and water-tube boiler tubes
• Marine heat exchangers — re-tubing seawater coolers during drydocking
• HVAC chillers — replacing failed chiller condenser and evaporator tube bundles
• Sugar, chemical and process plant exchangers — end-of-life tube replacement

8. Shingare Re-Tubing Tools

Shingare Industries supplies the complete re-tubing toolkit — both the tube removal tools covered here and the tube expanders that install the new tubes:

• Internal pipe cutters — for severing tubes inside the tube sheet, in a range of sizes for standard heat exchanger and boiler tube IDs.
• Tube pullers — spear-type, collet-type and hydraulic pullers for extracting tubes and stubs.
• Tube expanders — mechanical and hydraulic, for installing and expanding the new tubes.
• Tube cleaning machines — for cleaning tubes before inspection and re-tubing decisions.

9. Best Practices

• Cut at the right depth: Position the internal cutter to sever the tube just inside the tube sheet — not so deep that it damages the tube sheet face.
• Protect the tube sheet: Collapse stubs inward gently; avoid gouging or enlarging the tube sheet holes, which must accept new tubes.
• Match tools to tube size: Use cutters and pullers sized correctly for the tube ID for clean cuts and secure grip.
• Inspect tube sheet holes: After removal, clean and inspect each hole; minor damage may need re-machining before new tubes are fitted.
• Plan for volume: For full-bundle re-tubing with thousands of tubes, use continuous/powered pullers to keep the job on schedule.

10. Safety

• Isolation: The heat exchanger must be fully isolated, drained, cooled and decontaminated before tube removal.
• Manual handling: Removed tubes can be long, heavy and have sharp cut edges — use proper handling and PPE.
• Hydraulic safety: Hydraulic pullers operate at high force — follow hydraulic safety procedures and inspect equipment before use.
• Confined space: Working inside channel heads or around tube sheets may involve confined space procedures.
• Eye protection: Cutting and grinding produce metal chips — eye and face protection required.

This article is general technical guidance. Re-tubing must be performed per equipment procedures, applicable codes (including boiler regulations for boiler re-tubing) and site safety requirements by competent personnel.

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