Whats the difference between PEX-a, PEX-b and PEX-c tubing?
Currently, three methods for producing crosslinked polyethylene (PEX) tubing exist: • Engel or peroxide method (PEX-a) • Silane method (PEX-b) • E-beam (electron beam) or radiation method (PEX-c) All three processes generate tubing that is crosslinked to varying degrees, and are acceptable for potable water distribution applications according to ASTM F876 and F877 standards. Uponor manufactures Engel-method PEX-a tubing. The PEX tubing industry considers this tubing superior because the crosslinking is done during the manufacturing process when polyethylene is in it amorphic state (above the crystalline melting point). Because of this, the degree of crosslinking reaches around 85% (higher than the other methods), resulting in a more uniform product with no weak links in the molecular chain. Learn more about why PEX-a tubing is better.