HDPE Water Supply Pipe

Performance Advantages

• High Flexibility:

The elongation at break of HDPE water supply pipes is required to be over 350%, typically exceeding 500% or more. It exhibits strong adaptability to uneven settlement of the ground and excellent seismic resistance.

• Corrosion Resistance:

HDPE material possesses stable properties and is an inert material. Except for a few strong oxidizing agents, it canwithstand the corrosion of various chemical media without undergoing electrochemical corrosion.

• UV Resistance:

Polyethylene pipes containing uniformly distributed carbon black at 2-2.5% can effectively resist damage from ul-traviolet rays in sunlight. They remain undamaged when stored or used outdoors, exposed to UV radiation.

• Environmental Friendliness:

No heavy metal stabilizers are added during the processing of HDPE water supply pipes. The material is com-pletely non-toxic, does not form scale layers, does not foster bacterial growth, and prevents secondary pollution of urban water supply.

• Strong Conveying Capacity, Low Water Flow Resistance:

HDPE pipes feature a smooth inner surface with a Manning's coefficient of 0.009. The smooth surface and non-adhesive properties ensure that HDPE pipes have higher conveyance capacity than traditional pipes, simul-taneously reducing pressure loss and water conveyance energy consumption.

• Reliable Connection Performance:

HDPE water supply pipes use heat fusion or electrofusion for connections. The interface strength is higher than that of the pipe itself, and the joints will not disconnect due to soil movement or external loads.

Application Scope:

• Agricultural irrigation pipelines

• ground-source heat pump water supply pipelines

• urban water supply system upgrades

• industrial material conveyance

• urban functional infrastructure construction.

Product Differences

This product is a dedicated pressure‑bearing water supply pipe (with blue stripes, pressure‑grade spray marking, qualified wall thickness and sanitary performance), which is different from non‑pressure PE drainage pipes. Drainage pipes are pressure‑free, without blue stripes, thin‑walled and fail to meet drinking‑water standards. They must not be used as a substitute for water supply pipes.

HDPE Water Supply Pipe Selection Guide

Ⅰ、Select by working pressure

• First, determine the actual long-term operating water pressure of the pipeline, and make sure the pipe's nominal pressure (PN) is ≥ the system's maximum operating pressure; it's advisable to leave a safety margin.

• PE100 is preferred; PE80 shall only be used for old small-scale low-pressure projects and is not recommended for new construction works.

• For high static-pressure pipe networks, secondary water-supply pressurization and long-distance directional drilling, SDR11 PN1.6 is preferred; for ordinary municipal tap-water applications, SDR17 PN1.0 shall be selected.

Ⅱ、Select based on the type of medium being transported

• Drinking water: You must use HDPE water pipes that meet GB/T13663.2‑2018 standards and have a drinking water hygiene test report. Irrigation pipes can't be used instead.

• Clear water and industrial chilled water: HDPE water pipes can be used; do not transport strong organic solvents or highly corrosive high-temperature chemicals.

• Water supply for both agricultural and human‑animal use: Water supply pipes must be used, and GB/T23241 irrigation pipes shall not be adopted.

Ⅲ、Select by burial depth

• Buried depth determines the external overburden load, and model selection shall be made in combination with the pressure rating:

• Shallow burial (0.6‑1.5 m, sidewalks, green belts): Standard SDR17 PN1.0, backfill shall be carried out in strict accordance with specifications, with sand‑gravel bedding.

• Moderate burial depth (1.5‑3.0 m, under carriageway): SDR13.6 / SDR11 is preferred with increased wall thickness to resist overburden and vehicle dynamic loads.

• Buried depth ＞3m: Select SDR11 PN1.6; complete sand‑and‑gravel backfilling of the trench to prevent pipe damage caused by local stress.

• The greater the burial depth, external soil compression must be considered in addition to internal pressure, and thin‑wall large‑SDR series should not be blindly selected.

Ⅳ、Select by medium temperature

• HDPE is only suitable for cold water; the allowable working pressure shall be derated as temperature rises:

• ≤20℃: Use at the nominal PN pressure.

• 20‑40℃: The actual allowable working pressure shall be reduced, and the reduction increases with rising temperature.

• >40℃ environment: HDPE water supply pipes are not recommended, and hot‑water conveyance is strictly prohibited.

• Low‑temperature environment (-20℃ frozen soil): PE100 delivers better low‑temperature impact resistance than PE80. Avoid striking the pipes violently during construction under low‑temperature conditions.

Ⅴ、Select by foundation / geological conditions

• Ordinary stable foundation: Standard PE100 pipes are sufficient. HDPE flexible pipes can tolerate minor uneven settlement.

• Soft soil, backfill soil and large‑settlement areas: Prioritize the PE100 SDR11 heavy‑wall series; Prefer electro‑fusion / hot‑melt butt‑welding to ensure the integrity of joints; A sand bedding layer must be constructed in trenches, and direct contact between stones and pipe walls is prohibited.

• Rock foundation: A fine sand cushion layer shall be laid in the trench to prevent sharp rock edges from scratching the outer wall of the pipe.

• Saline‑alkali and corrosive soils: HDPE features outstanding corrosion resistance and requires no anti‑corrosion treatment.

Ⅵ、Select by connection method

• For large‑scale on‑site installation of straight pipes with dn≥63: butt fusion welding features low construction costs.

• dn20‑dn63 small coiled pipes, underground operations, confined spaces, emergency repairs, trenchless directional drilling: electrofusion connection.

• Connection of pipes of different materials (steel pipe‑PE pipe): Use steel‑plastic transition fittings. Direct welding or threading onto the PE pipe body is prohibited.

• Prohibited: Bonding with adhesive and direct connection of PE pipes with PVC fittings.