"Look" at the Appearance
Color: Good PP-R water pipes have a soft, uniform color without any impurities. (PP-R pipes mainly come in several colors, including white, gray, purple, green, yellow, and blue. Consumers often believe that white is the best, but color is not a standard for judging quality. In fact, the quality of PP-R water pipes has nothing to do with their color. Plastic particles are mainly white and transparent (other colors are also available with added masterbatch). As long as masterbatch is added, any color can be produced. The masterbatch will not decompose or change the quality of PP-R. Therefore, for water pipes, the color doesn't matter. According to national regulations, PP-R water pipes must have good light-blocking properties. In this respect, gray or other opaque colors are better.) Some. However, this advantage only exists in exposed pipe installations and pipe shafts. Home water pipes are all concealed, so there's no basis for the claim that gray is superior to other colors. PP-R pipes are completely opaque, while pseudo-PP-R pipes are slightly translucent or semi-translucent. White products can generally only be produced using pure PP-R raw materials. Products made with recycled materials, waste, or scraps will have an uneven and less vibrant color. Conversely, adding recycled materials, waste, or scraps to other colored products processed with color masterbatch will not affect the color. This is why many manufacturers focusing on quality and primarily selling home improvement products mainly use white. The inner and outer surfaces of the product should be smooth and flat, without defects such as bubbles, obvious dents, grooves, or impurities.
"Touch" the Texture
Good PP-R water pipes are 100% made of PP-R raw material (without any additives), with a pure texture, smooth surface, and soft feel. Counterfeit PP-R pipes feel smooth to the touch; generally, those with coarse particles are likely mixed with impurities.
"Smell" the Odor
The main material of PP-R pipes is polypropylene. Good pipes have no odor, while inferior pipes have a strange smell, which may indicate the addition of polyethylene instead of polypropylene.
"Squeeze" the Hardness
PP-R pipes have considerable hardness. Pipes that can be easily deformed by squeezing are definitely not PP-R pipes.
"Measure" the Wall Thickness
Alternatively, you can use calipers to measure whether the pipe wall thickness meets the standard and is uniform. Good pipes are generally manufactured strictly according to national standards, but this method requires some understanding of the national standards for PP-R pipes.
"Listen" to the Sound
PP-R pipes produce a duller sound when dropped, while counterfeit PP-R pipes produce a crisper sound.
"Smashing" Resilience
Good PP-R pipes have good "resilience." Pipes that are easily broken are obviously not good PP-R pipes. However, even the best PP-R pipes can be broken at temperatures below 10 degrees Celsius. But high hardness does not equal good elasticity. Some manufacturers add excessive amounts of calcium carbonate and other impurities to increase hardness, making them unbreakable but prone to brittleness over time. (The cold brittleness of PP-R raw materials varies across several temperature ranges: 10, -5, -23...)
"Burning" Smoke and Odor
PP-R pipes mixed with recycled plastics and other impurities will emit black smoke and have a pungent odor. Good quality PP-R pipes, on the other hand, will not emit black smoke or have any odor when burned, and the molten liquid will remain clean. (Alternatively, you can "pull" it to observe its "length".)
"Fusion"
The normal welding temperature for PP-R pipes is within the range of 260-290℃. Welding within this temperature range ensures better weld quality. If, under normal welding parameters, the product easily enters the welding die and the weld bead is almost liquid, it indicates the product is not made from genuine PP-R material. Furthermore, if the weld bead cools and hardens rapidly (generally within 10 seconds), it also indicates the product is not made from genuine PP-R material. This is because one of the characteristics of PP-R is its good heat insulation, resulting in a slower cooling rate.
Check for deformation of the pipe's inner diameter and for stringing of the fittings. Good PP-R pipes do not string and their inner diameter is not easily deformed.
"Inspection"
Using testing instruments to conduct inspections effectively distinguishes between superior and inferior products. The national standard specifies several important test requirements, such as the pipe aging resistance test (a test that ensures the pipe does not fail for 8760 hours under a ring stress of 1.9 MPa and a test temperature of 110℃), the pipeline system stability test (5000 cycles of thermal cycling), and the impact resistance test. Therefore, users can request the manufacturer or supplier to provide the above test reports for verification when selecting pipes and fittings. It should also be noted that the national standard has an important requirement for the raw materials used in pipes and fittings: the melt flow index. The national standard requires that the change in melt flow index before and after processing should not exceed 30%, and the industry also has a requirement that the melt flow index of the raw materials should not exceed 0.5 g/10 min.
