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How to choose ppr pipe fittings?

Feb. 19, 2021

There are many manufacturers of PPR pipe fittings and pipes. The raw material of PPR pipe fittings and pipes is polypropylene (random copolymer polypropylene). PPR pipe fittings and pipes are produced from different brands of raw materials. There are certain differences in performance, plus the level of production line. Different, the quality of PPR pipe fittings produced by various manufacturers has a large gap between good and bad. When using PPR pipe fittings, it must be inspected before installation, and the PPR pipe fittings can only be used after the quality is confirmed to be qualified. The selected ppr pipe fittings and pipes should first have the quality inspection report of the quality inspection department, and the ppr pipe fittings used for drinking water should also have the sanitary performance inspection report of the sanitary inspection department, and then the appearance quality of the pipes and fittings and the pipe should be inspected. Diameter and wall thickness, when inspecting ppr pipe fittings and pipes, the following items are mainly inspected according to national standards:

1. The appearance of ppr pipe fittings.

The color of ppr pipe fittings and pipes should be basically the same. The inner and outer surfaces of ppr pipe fittings and pipes should be smooth and flat without dents, bubbles and other surface defects that affect performance. PPR pipe fittings and pipes should not contain visible impurities; the surface of ppr pipe fittings should be smooth, flat, and not Defects such as cracks, bubbles, peeling and obvious impurities, severe shrinkage, uneven color, decomposition and discoloration are allowed.

2. The opacity of ppr pipe fittings.

Ppr pipe fittings and pipes should be opaque.

ppr pipe

3. Pipe diameter and wall thickness of ppr pipe fittings.

According to GB/T18742.2-2002 national standard, ppr pipe fittings are divided into five series according to size: S5, S4, S3.2, S2.5, and S2. There is a corresponding relationship between ppr pipe fittings and pipe series S and nominal pressure. The specifications of ppr pipe fittings are represented by pipe series S and nominal outer diameter dn* nominal wall thickness en. Ppr pipe fittings mainly inspect the nominal outer diameter, average outer diameter and The corresponding wall thickness of 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 ppr pipe fittings.

Whether the hydrostatic test of ppr pipe fittings, the mass flow rate of melt, the thermal stability test under hydrostatic state, the longitudinal shrinkage rate of the pipe, and the impact test of simple beams meet the national standards, the inspection of materials for ppr pipe fittings can be checked. The content of the report and the retest report.

5. Whether the sanitary performance of ppr pipe fittings meets the national standards.

Ppr pipe fittings and pipes This item can be used to check the sanitary performance inspection reports of ppr pipe fittings and pipes by the health inspection department.

6. Applicability of ppr pipe fittings and pipe systems.

After the ppr pipe is connected to the pipe, it should pass the combined test of 8760 hours of internal pressure and 5000 thermal cycles.

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