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4 technical reasons why PEX-a pipe is best for plumbing Private

1 month ago Fashion, Home & Garden Baltimore   14 views

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In an era when plumbing systems are continuing to advance from metal to plastics, contractors are speculating which plastic piping system is best. The right answer can be found by learning some technical facts about crosslinked polyethylene (PEX) pipe — a flexible, durable, plastic piping material that has been used for decades in plumbing and floor heating pipe applications worldwide.


While all PEX pipe must adhere to specific standards for temperature and pressure ratings and pipe-wall thickness, many variables in the manufacturing methods of PEX affect pipe performance. This article will address four technical attributes of PEX to guide you in choosing the best plumbing system for a structure.


Currently, there are three methods to produce PEX, called PEX-a, PEX-b and PEX-c. With the Engel-method PEX-a manufacturing process, there are no “interference” atoms between the HDPE molecules. Hence, this achieves a direct carbon-to-carbon bonding and the highest degree of crosslinking (around 85%) for the most flexible and durable PEX AI PEX piping product.

No. 2: Maximum resistance to stress cracking for the strongest system

ASTM International is the standards organization that develops and publishes voluntary technical standards to ensure public health and safety. All PEX pipe manufactured and sold in North America is tested by ASTM — as well as various other testing, listing and standards agencies — to ensure the product is manufactured, installed and performs according to strict parameters.

The test uses six randomly selected PEX pipe with PEX pipe fitting specimens and cuts a 1-inch notch on the inside of the pipe at a 10% depth of the pipe wall. The pipes are filled with the test medium, which is typically 5% “IGEPAL CO-630” (an ESCR-accelerating agent), mixed with 95% untreated water.

Additionally, several metal ions (mainly copper and iron) are found in water due to the dissolution of metal ions from the carrier pipes feeding the plumbing system with brass valve or in metal components of the plumbing system. Hence, it is imperative that plumbing system pipes are able to withstand variations in water chemistry for prolonged periods of time.


Internal testing conducted using changing water chemistry (pH, soluble salts, etc.) and using increased metal ions showed PEX-a has superior resistance when compared with other plastic pipe tool. So when it comes to chemical resistance, aggressive vapors and durability, PEX-a is the strongest, most durable pipe in harsh plumbing conditions.