Polyethylene (PE) pipe goes through the e-beam process and becomes crosslinked (X). That is how we put the “X” in PEX. Polyethylene is the most common polymer we electron beam crosslink every day. We see it in different forms, from injection molded and thermoformed parts, extruded sheet, tubing and wire and cable. While there are many success stories about the great products we have the opportunity to crosslink every day, I don’t think there is a better example than PEX pipe.
While many of the products we e-beam are used in products you touch, see, and benefit from every day, PEX tubing is something you may overlook. In fact, it is so common and successful that you may not even know that you are already using it in your home. The product has become the choice of most builders as it provides a lower-cost, easier-to-install plumbing product compared to copper pipes. In addition, it provides the benefits of plastic that cannot be achieved with metals.
E-beam is considered a physical crosslinking process, where the electrons themselves cause a breaking of the chemical bonds and then the polyethylene chains reform. Then they link to each other, ultimately making each piece of PEX tubing just one united chain of polyethylene. This change results in an increase in its standard continuous usable temperature to 180°F from 140°F, and additionally it can withstand up to 230°F.
The “X” is the difference between a good cold water pipe, and a great cold AND hot water product in PEX pipe. Like many of the polyethylene products we e-beam, PEX tubing benefits from substantially improved high temperature operation. Another benefit: PEX is able to withstand the occasional frozen water incident, something even copper won’t do!
(pssst…..check out We put the “X” in PEX: The Movie!)