The quality of HDPE pipes depends on the raw material used, processing equipment and technology. To begin with, we take an appearance
1. Appearance In good quality HDPE pipes, the inside and outside surface will be smooth. They will not exhibit defects like bubbles, dents, impurities, etc.
2. Milling strips The strips of good quality HDPE pipes that are milled by welding machine display a bright color, neat and do not break by repeated folding. The milling strips with a whitish color, or other colors, which are caused by adding recycling material or uneven material mixing.
3. Butt Welding Joint The desired butt welding joint will display smooth and symmetrical turn-ups around the pipe circles, and the turn-ups depth do should not lower than the pipe surface. The alignment tolerance at two sides in the ex-circle of welding seams should not exceed 10% of pipe thickness. The turn-ups should be solid and smooth, while the bottom part should be somewhat wider. The turn-ups should not display impurities, small holes, deformation and damages at the downside.
4. Break Elongation It is that ratio between the length when broken and the original length. When break elongation is more, flexibility and performances are better. Good quality HDPE pipes can be stretched 3.5 times of the original length without breaking.
5. OIT OIT(Oxidative induction time) is that time for the pipes to undergo Automatic Catalytic Oxidation reaction under higher temperature and oxygen, which displays the thermal degradation capacity of the HDPE pipes during processing, storage, welding and working. If OIT is longer, better is the anti-aging capacity of HDPE pipes.
In addition, you can also choose HDPE pipe manufacturers and suppliers certified by relevant industry standards according to the pipeline use and engineering requirements. Puhui HDPE pipe has various certificates, such as UL/SAA/WRAS/ISO/CE/NSF/CNAS Certificates. You can contact us and send inquiry. Email: [email protected] | [email protected]