1. The appearance of ppr pipe fittings. The color of the pipe should be basically the same. The inner and outer surfaces should be smooth and flat, free of dents, bubbles and other surface defects that affect performance, and should not contain visible impurities; the surface of the pipe should be smooth and flat, and no cracks, bubbles, peeling and obvious Impurities, severe shrinkage, uneven color, decomposition and discoloration.
2. The opacity of pipe fittings. Pipe fittings should be opaque.
3. The diameter and wall thickness of the pipe fittings. According to the GB/T18742.2-2002 national standard, the pipes are divided into five series according to the size of S5, S4, S3.2, S2.5 and S2. The pipe series S has a corresponding relationship with the nominal pressure. The pipe specifications are represented by the pipe series S and the nominal outer diameter dn* nominal wall thickness en. The main inspections are the nominal outer diameter, average outer diameter and wall thickness corresponding to the pipe series. The socket size of the pipe fitting and the corresponding nominal outer diameter.
4. Physical and mechanical properties and chemical properties of pipe fittings. Whether the hydrostatic pressure test, melt mass flow rate, thermal stability test under hydrostatic state, longitudinal shrinkage rate of pipes, and simply supported beam impact test comply with national standards, you can check the content of the material inspection report and retest report. .
5. Whether the sanitary performance of pipe fittings meets national standards. This item can be used to check the sanitary performance inspection report of the pipe and fittings by the sanitation inspection department.
6. System applicability. After the pipe is connected with the pipe fittings, it shall pass the combined test of 8760 hours of internal pressure and 5000 thermal cycles.