Gas polyethylene pipelines possess numerous outstanding features and are applied in the field of gas transportation, effectively addressing the corrosion and joint leakage problems associated with traditional steel and cast iron pipes, thereby ensuring the safe operation of gas network systems. In fact, PE pipes are widely used in the gas distribution networks of many large cities. PE pipes are also extensively utilized in the mining industry for transporting slurry, as well as in the chemical, telecommunications, agriculture, irrigation, and air conditioning industries. 1. Polyethylene gas pipes have the following characteristics: 1. Long service life — Under rated temperature and pressure conditions, PE pipes can be safely used for over 50 years. 2. Excellent corrosion resistance — Except for a few strong oxidants, they can withstand the erosion of various chemical media; no electrochemical corrosion occurs. 3. Outstanding abrasion resistance — The wall friction coefficient is low, resulting in small flow resistance and strong delivery capacity. When transporting sand slurry, the abrasion resistance of PE pipes is more than four times that of steel pipes. 4. Excellent resistance to slow crack growth (SCG) and rapid crack propagation (RCP). 5. Good hygiene performance — No heavy metal salt stabilizers are added during the processing of PE pipes, making the material non-toxic, free from scaling, and resistant to bacterial growth, effectively addressing secondary pollution in urban drinking water. 6. Reliable connection performance — The strength of the PE pipe's heat-fusion or electro-fusion joints exceeds that of the pipe body itself, and the seams will not break due to soil movement or load. 7. Good construction performance — The pipes are lightweight, with a simple welding process and multiple trenchless methods available, greatly facilitating construction and installation. 8. Low system cost and maintenance expenses can significantly reduce overall project costs. a. Standards: GB/T 15558.1-2005 GB/T 15558.2-2005 b. Technical regulations: CJ63-95 Technical requirements for PE gas pipes: | Item | | Technical Requirements | |---------------------------|--|-----------------------------------------------------------| | Appearance | | The inner and outer surfaces of the pipe should be smooth and flat. Bubbles, obvious scratches, dents, impurities, and uneven color are not allowed. The ends of the pipes should be cut flat and perpendicular to the pipe axis. | | Thermal Stability (200°C), min | | >20 | | Break Elongation, % | | ≥350 | | Longitudinal Shrinkage, % | | ≤3 | | Melt Flow Rate (MFR), g/10min (190°C, 5kg) | | MFR change before and after processing <20% | | Static Hydrostatic Strength | | PE80 | | | --------------------------- |--| ------------------------ | -------------------------------------------------- | | 20°C, circumferential stress | | 9.0 MPa, failure time ≥ 100h | | 80°C, circumferential stress | | 4.5 MPa, failure time ≥ 165h | | 80°C, circumferential stress | | 4.0 MPa, failure time ≥ 1000h | | Static Hydrostatic Strength | | PE100 | | | --------------------------- |--| ------------------------ | -------------------------------------------------- | | 20°C, circumferential stress | | 12.4 MPa, failure time ≥ 100h | | 80°C, circumferential stress | | 5.4 MPa, failure time ≥ 165h | | 80°C, circumferential stress | | 5.0 MPa, failure time ≥ 1000h |