expansion, press, crimp & cinch

Interplay Learning: Joining PEX Pipe and Tube Methods

Introduction

This lesson focuses on advanced joining methods for PEX (cross-linked polyethylene) pipes and tubes, including expansion, press, crimp, and cinch fittings. Emphasis is placed on ensuring the proper technique and adherence to manufacturer specifications.

Overview of Joining Methods

PEXS A, B, and C vary in compatibility with different joining techniques. It is critical to refer to specific manufacturer guides for each type of fitting used.

1. Expansion Joints

Expansion joints can only be utilized with PEX A piping due to its unique memory properties.

Steps to Join Using Expansion:

  1. Measure and Cut: Prior to joining, accurately measure and cut the tubing to the required length.

  2. Obtain Necessary Materials: Acquire the PEX A ring and the appropriate fitting for your application. Always consult the manufacturer's instructions to confirm compatibility.

  3. Placement of Ring: The ring must be placed over the tubing, ensuring it is flush with the end of the tubing and not sliding down.

  4. Using the Expansion Tool: Insert the expansion tool into the pipe. Pump the tool the specified number of times according to the pipe size and the manufacturer's instructions.

    • Example: For 1/2 inch PEX A tubing, pump the manual tool 3-4 times. Ensure to rotate the head of the tool one-eighth of a turn before the final pump.

  5. Insert the Fitting: Immediately insert the correct fitting into the expanded tubing. If the fitting does not seat fully, remove it immediately and repeat the expansion process by pumping 2-3 more times.

2. Press Fittings

Press fittings can be used with both PEX A and PEX B. It’s critical to note that while the various PEX joint types have become interchangeable, it is strictly prohibited to mix fittings from different manufacturers.

Steps to Join Using Press:

  1. Prepare the Tubing: Cut the tubing to the appropriate length, ensuring the cut is square.

  2. Install the Press Fitting: Slide the press fitting into the tubing until it stops.

  3. Use the PEX Press Tool: Locate the hand or powered PEX press tool as per the manufacturer's guidance. Some fittings have a visibility hole to ensure proper insertion of the pipe into the fitting. Make a test mark for visibility if no indicator is present.

  4. Press the Fitting: Activate the hand-operated or powered tool until it halts.

  5. Inspect the Joint: After removing the tool, check to ensure the tubing is fully inserted into the fitting.

3. Crimping Method

Crimping requires specific tools tailored to the size of tubing being utilized. This method ensures a secure connection and leak-free joint.

Steps to Join Using Crimping:

  1. Cut the Tubing: Measure and cut the PEX tubing squarely.

  2. Gather Materials: Obtain the copper crimp ring, suitable crimping tool, and a barbed fitting.

  3. Slide on Crimp Ring: Place the copper crimp ring over the tubing and insert the fitting into the pipe.

  4. Position the Crimp Ring: Open the crimping tool's jaws and set the crimp ring to be exactly one-sixteenth of an inch from the face of the tubing being cut.

  5. Compress the Tool: Close the handles of the crimping tool until it cannot compress further, forming a secure crimp.

  6. Calibration Check: Always reference manufacturer's specifications for tool calibration to ensure effectiveness.

4. Cinch Clamp Method

Cinch clamps are compatible with PEX B and C, enabling a reliable pipe joint.

Steps to Join Using Cinch Clamp:

  1. Prepare the Tubing: Measure and cut the piping squarely to length.

  2. Get Necessary Items: Obtain the stainless steel crimp ring, appropriate crimping tool, and barbed fitting.

  3. Install the Barbed Fitting: Insert the barbed fitting into the tubing and slide the cinch clamp over.

  4. Adjust the Clamp: Open the jaws of the cinch clamp tool, align, and attach the clamp. Set the clamp to be one-eighth inch to three-sixteenth inch away from the tubing face.

  5. Cinch the Clamp: Compress the cinch tool handles until it bottoms out. Verify that the joint is secure.

  6. Final Check: Remove the tool from the fitting to complete the process.

Conclusion

This lesson detailed the processes involved in joining PEX with expansion, press, crimp, and cinch fittings, highlighting the importance of specificity to manufacturer instructions and accurate measurements. Understanding these techniques will equip users with the skills required to ensure reliable plumbing applications. A follow-up lesson will delve into further PEX methodologies and applications.