What are the common defects caused by insufficient heating time in Socket Fusion Fittings?

Common defects caused by insufficient heating time:

1. Incomplete fusion → Insufficient joint strength and easy leakage:

Low temperature or insufficient heating time will cause the pipe wall and joint wall to not melt sufficiently, forming a "cold weld" or "false fusion". The joint is prone to micro-cracks and leakage under pressure.

2. Root defects and reduced fatigue strength:

Insufficient melt flow in Socket Fusion Fittings will cause voids or unfused areas at the root, resulting in a significant reduction in strength in rotational bending fatigue tests, especially in small-diameter pipes.

3. Increased joint brittleness and easy cracking:

Too low a heating temperature will cause the polymer molecular chains to not rearrange sufficiently. The joint will exhibit brittle failure under temperature cycling or impact loading, resulting in yellowing or surface cracks.

4. Porosity and internal defects:

Insufficient melt flow will form pores or micro-voids of unfused material inside the joint. These defects are prone to leakage and accelerate material aging during later use.