Your PEX Questions Answered

UV resistance does not depend on the resin, but rather is influenced by the carbon black content and stabilizers. For example: HDPE with no carbon black (2%) will not be UV resistant. 

Pexgol pipes are made of PeXa resin with carbon black additives and stabilizers, which make the pipe black and completely UV resistant. The debate on PEX not being UV resistant has come up because the majority of PEX manufacturers serve an industry where pipes are mostly covered, buried, or indoors, where there is no sun and, therefore, no need to add the carbon black. These PEX pipes are opaque (also called natural) rather than black and not UV resistant.

PeX-a is the original method of producing PEX. It uses a peroxide catalyst to cross-link the pipe during the extrusion process. While this is a more complicated form of extrusion, it ensures the pipe is cross-linked and ready to be installed once leaving the extrusion. It is also the zero energy state, which is the base for the material's thermal memory. 

PeX-b is a more simple method of extrusion for PEX pipes. The cross-linking catalyst is silane, which crosslinks in the presence of moisture. The cross-linking, in this case, is done post-extrusion. 

PeX-c is a process where the pipe is cross-linked by using a form of radiation. It is a very cost-effective method; however, this method is limited by the wall thickness of the pipe through which radiation can effectively penetrate. It is therefore limited to small diameter plumbing pipes. 

The cross-linking of molecular chains in pex adds to the structural stability of the material. When a non-cross-linked material is heated, the individual molecular chains can easily move, leading to a pipe wall rapture. In a cross-linked material, this rapture cannot happen as the molecular chains are all connected and cannot move easily.

In small plumbing type PEX pipes, there are a variety of mechanical fittings. When we increase the pipe size and wall thickness, connection depends on your applications. Connections can be mechanical like flanges, Victaulic Style, and others. You can also use electrofusion for low temperatures or reinforced electrofusion for elevated temperatures.

No. PEX pipes do not melt, and therefore cannot be butt fused.

Yes. You can use electrofusion socket couplers with Pexgol pipes. While the Pexgol itself does not melt, the heat “melts” the areas between the crosslinks, allowing the polyethylene melt to combine with the Pexgol material. 

When you want to replace a metallic pipe with Pexgol, the main thing you need to keep in mind are how IPS sizes can differ. In metallics, the IPS size is nearly the internal diameter of the pipe, while in plastics, the OD can be very different than the ID.

To avoid any flow problems, you should consult with us. We will be happy to guide you in the specification process using our engineering guide.

The temperature rating for Pexgol is based on both industrial experience in temperatures of up to 114°C/237°F, and on long-term third-party testing in long-term exposure in hot water (3.5 years at 110°C/230°F).

Yes. Pexgol NRG pipes are typically insulated on site with our Split Tube Insulation system, or our Pour-in-Place method. This allows you better use of our coiled pipe options.

Pexgol pipes are currently manufactured in sizes up to 710mm (18”). However, this is not the maximum limit; it is a matter of demand.