PEX Crimpers & Expansion Tools
PEX (cross-linked polyethylene) tubing has changed plumbing and radiant heat. Joints are made with crimp rings, cinch clamps or expansion fittings, using hand or battery tools. The tools are simple, but jaws pinch, cutters slice and a bad connection can fail under pressure and flood a building.
- Plumbers
- HVAC & Radiant Heat Installers
- Remodelers
- Homeowners
Common PEX tools
- Tube cutters (scissor-style) for clean square cuts.
- Crimp tools that compress a copper ring around the fitting (check with a go/no-go gauge).
- Cinch tools that tighten a stainless clamp with a tab.
- Expansion tools (hand or battery) that expand the tube end for a fitting that then shrinks tight.
- Push-fit and press fittings that need little more than a cutter and deburring tool. See Press Fitting Tools.
Main hazards
- Pinched or crushed fingers in crimp jaws and tool handles.
- Cuts from sharp tube cutters and from cut tubing ends.
- Eye injuries from debris and from tool jaws slipping.
- Failed connections that leak or burst, causing flooding and water damage. Poor crimps are a top cause.
- Repetitive strain from squeezing many crimps. Battery tools help. See Ergonomic Hand Tools.
- Battery hazards from charging and storage. See Battery Safety.
- Tight spaces and overhead work in joists and walls.
- Heat, UV and chemicals: PEX is damaged by sunlight, some solvents and open flames.
Safe use
- Wear safety glasses and cut-resistant gloves when cutting and handling tube.
- Cut square and clean, remove burrs, and make sure the tube end is dry and free of scratches. Don't use a damaged section.
- Use tools made for the system (crimp, cinch or expansion). Don't mix rings, clamps and tools from different systems unless the maker says they match.
- Insert the fitting fully, place the ring or clamp at the specified distance from the end, and make the connection square to the tube.
- Check every crimp with a go/no-go gauge, and recheck tool calibration regularly. Adjust or repair out-of-spec tools.
- Keep fingers away from jaws and hold the work still. Don't crimp a ring that's partly off the fitting.
- Protect PEX from UV light, flame, and contact with solvents or petroleum products. Don't use it where a torch is used nearby. Follow code limits for support and bends.
- Pressure test the system before closing walls, and look for leaks. Stay clear during the test.
- Don't use plastic piping as an electrical ground. Follow local code. See Plumbing & Pipefitting.
PEX tool checklist
- I wear safety glasses and cut-resistant gloves
- Cuts are square, clean and deburred; fittings are fully inserted
- Rings, clamps and tools match the system, and each crimp is gauged
- PEX is kept from sunlight, flames and solvents
- The system is pressure tested before it is closed in
Standards & references
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