How to choose ppr pipe fittings
At present, there are many manufacturers of ppr pipe fittings. The raw material of ppr pipe fittings is polypropylene (random copolymerization polypropylene). The products produced by ppr pipe fittings using different brands of raw materials have certain differences in performance, plus the level of the production line is different. There is a big gap between the quality of ppr pipes produced by various manufacturers. When using PPR pipe fittings, inspection must be performed before installation. PPR pipe fittings can be used only after they are qualified. The selected ppr pipe fittings should first have the quality inspection report of the quality inspection department. Among them, the ppr pipe fittings used for drinking water should also have the hygienic performance inspection report of the sanitary inspection department, and then the appearance quality of the pipes and fittings and the pipe Diameter and wall thickness, the following items are mainly inspected in accordance with national standards when inspecting ppr pipe fittings:
1. Appearance of ppr pipe fittings. The color of the ppr pipe should be basically the same. The inner and outer surfaces of the ppr pipe should be smooth and flat without dents, bubbles and other surface defects that affect performance. The ppr pipe should not contain visible impurities; the surface of the ppr pipe should be smooth and flat. Defects such as cracks, bubbles, peeling and obvious impurities, severe shrinkage, uneven color and discoloration are allowed.
2, opacity of ppr pipe fittings. PPR pipe fittings should be opaque.
3. The diameter and wall thickness of ppr pipe fittings. According to the national standard GB / T18742.2-2002, ppr pipe fittings are divided into five series: S5, S4, S3.2, S2.5, and S2. The series S of ppr pipe fittings has a corresponding relationship with the nominal pressure. The specifications of ppr pipe fittings are represented by the pipe series S and the nominal outside diameter dn * the nominal wall thickness en. The ppr pipe fittings are mainly used to check the nominal outer diameter, average outer diameter and The corresponding wall thickness of the pipe series, the socket size of the pipe fittings and the corresponding nominal outer diameter.
4. Physical and mechanical properties and chemical properties of ppr pipe fittings. The hydrostatic test of ppr pipe fittings, melt mass flow rate, thermal stability test under hydrostatic state, whether the longitudinal shrinkage of the pipe, and the impact test of simply supported beams meet the national standards. Report content and retest report content.
5. Whether the sanitary performance of ppr pipe fittings complies with national standards. ppr pipe fittings This item can check the sanitary performance inspection report of ppr pipe fittings by the health inspection department.
6. Applicability of ppr pipe fitting pipe system. After the ppr pipe fittings are connected to the pipe fittings, they should pass two combined tests of 8760 hours of internal pressure and 5000 thermal cycles.