The tapping of UV-discolored pressure pipes has been a topic of concern. However the, PVC pipe industry has found no evidence of tapping failures due to UV discoloration.
What causes PVC pipe failure?
PVC pipes occasionally fail due several reasons including: Defective pipe manufacture – The main manufacturing defects that cause PVC pipes to fail include incomplete resin fusion, incomplete fusion of extrusion knit lines (also called “weld lines” or “spider-lines”), and inhomogeneity of the filler content.
Does PVC rot in the sun?
Overall, PVC does not degrade in sunlight. PVC is made to be resistant to sunlight and therefore is unaffected by sunlight in any way. PVC is OK to use on the exterior and as a main cold water supply. However, PEX is typically much easier to install.
What happens to plastic when exposed to UV?
UV energy absorbed by plastics can excite photons, which then create free radicals. While many pure plastics cannot absorb UV radiation, the presence of catalyst residues and other impurities will often act as receptors, causing degradation.
How long does PVC pipe last in the sun?
PVC pipes and PVC fittings exposed to sunlight for periods of two years or longer will experience decreases in impact strength and resistance. This is not a major problem when dealing with PVC pipes and fittings as impact strength and resistance are not qualities generally associated with PVC.
Does PVC pipe deteriorate?
PVC is extremely porous, and can break down when too much cement is applied. But it’s just as bad to not use enough cement because bonds will be too weak.
What weakens PVC pipe?
Because PVC is a very porous material, too much cement can cause it to break down. Conversely, when too little cement is used, it can create weakened bonds that may leak or break.
Does UV damage PVC?
PVC does surprisingly well when exposed to ultra violet rays (sunlight). Research shows little to no effect on PVC’s tensile strength or elasticity after prolonged sun exposure. The only degradation that seems to occur is impact strength.
Does UV light damage PVC pipe?
When exposed to direct sunlight, CPVC and PVC shows “UV degradation”, but only between 0.001 to 0.003 inches. Once pipes are removed from the direct exposure, the ultraviolet rays no longer affect them. Long-term sunlight exposure can decrease the CPVC and PVC’s impact strength and resistance.
Is PVC pipe UV protected?
Based on these studies, Harvel Plastic, Inc. recommends that PVC and CPVC piping products (i.e. pipe, duct, & shapes) exposed to the direct effects of UV radiation be painted with a light colored acrylic or latex paint that is chemically compatible with the PVC/CPVC products.
Why is PVC unstable in sunlight?
However, PVC has low heat stability, with changes in shape and color occurring at high temperatures. Furthermore, long exposure of PVC to ultraviolet (UV) radiation, e.g., from sunlight, and a high temperature results in undesirable changes in its physical and chemical properties [6,7].
How do you protect UV from PVC pipe?
For permanent above-ground PVC pipe installations, it is recommended that the pipe be protected from sunlight exposure. This can be accomplished by wrapping the pipe with an opaque material, or more commonly, by painting it. If the pipe is to be painted, a water-based paint formulated for exterior use is recommended.
Is clear PVC UV resistant?
Clear PVC Pipe is UV resistant.
Which PVC pipe is best for outdoor use?
Crescent Plastics offers extruded PVC tubing that is specially formulated to be weather- and impact-resistant for longevity. PVC is known for its durability and ability to maintain its performance over an extended period.
Is Gray PVC UV resistant?
Blue, green, or purple pipe will “sun bleach.” Grey pipe will have brown or black streaks. UV discoloration does not occur where PVC is not exposed to sunlight, and ceases when exposure ends. The discoloration process is time dependent, and can be slowed with the addition of UV absorbers in the PVC compound.
What is UV PVC?
UV means Ultra-Violet light. Sun light and UV Lamps emit UV light. UV light generally degrades all plastics. PVC is one of the more resistant, however given enough time even PVC plastic fittings and pipe will change color (white to tan to brown to black) and become brittle.
