HDPE Pipe with Flange is a composite pipe that combines high-density polyethylene (HDPE) pipes with flange connectors, combining the excellent performance of HDPE materials with the convenience of flange connection. This type of pipe is widely used in occasions that require frequent disassembly, maintenance or connection with metal equipment, such as municipal water supply, industrial fluid transportation, chemical pipeline systems, etc.
1. Basic structure
HDPE pipe body: PE80 or PE100 grade high-density polyethylene is used, with excellent corrosion resistance and flexibility.
Flange joint: usually made of steel or HDPE, connected to the pipe body by hot melt or mechanical means.
Sealing gasket: EPDM rubber or silicone is commonly used to ensure the sealing of the interface.
2. Main features
Chemical corrosion resistance: suitable for acid, alkali, salt and organic solvent environments.
Lightweight: The weight is only 1/8 of that of steel pipes, reducing transportation and installation costs.
Long life: The designed service life is more than 50 years, and the maintenance cost is low.
Flexible installation: Flange connection is easy to disassemble and repair.
{C}1. {C}Comparison with traditional flanged steel pipes
|
Feature |
Flanged HDPE Pipe |
Flanged Steel Pipe |
|
Weight |
Light (easy to handle and install) |
Heavy (requires large equipment for lifting) |
|
Corrosion Resistance |
Excellent (no anti-corrosion treatment needed) |
Requires galvanizing or painting for protection |
|
Connection Method |
Butt fusion / flange options |
Flange or welding only |
|
Maintenance Cost |
Low (maintenance-free) |
High (requires regular anti-corrosion work) |
|
Applicable Temperature Range |
-60°C to 60°C |
-20°C to 400°C |
2. Core advantages
Good sealing: flange + gasket design achieves zero leakage, which is better than traditional welding.
Strong seismic resistance: HDPE flexibility can absorb foundation settlement or vibration stress.
Environmental protection and energy saving: production energy consumption is 70% lower than that of metal pipes, and it can be recycled.
1. Municipal engineering
Water supply network: connected with metal equipment such as valves and pump stations.
Sewage treatment: corrosion resistance is suitable for sludge and chemical agent transportation.
2. Industrial system
Chemical pipeline: connect reactors, storage tanks and other pressure vessels.
Food and medicine: meets FDA standards and is used for aseptic fluid transportation.
3. Special scenarios
Temporary pipeline: flange connection is easy to disassemble and assemble quickly, suitable for temporary water supply on construction sites.
Offshore platform: resistant to salt spray corrosion, used for seawater cooling system.
1. Flange connection steps
Pipe end treatment: Cut the pipe and polish the end to ensure flatness.
Flange assembly: Put the flange into the pipe end and fix it by hot melting or electric melting.
Gasket installation: Choose a gasket of suitable material (EPDM/NBR).
Bolt tightening: Tighten the bolts in diagonal order to avoid bias (torque is usually 50-60N·m).
2. Key points
Flange alignment: The bolt holes of the two flanges must be completely aligned, with a deviation of ≤1mm.
Pressure test: After installation, a pressure test of 1.5 times the working pressure is required (no leakage for 30 minutes).
Temperature difference compensation: Expansion joints are required for long pipes to prevent flange leakage due to thermal expansion and contraction.
{C}1. {C}Selection parameters
|
Parameter |
Typical Options |
|
Pipe Diameter |
DN50–DN1200 (commonly DN100–DN500) |
|
Pressure Rating |
PN0.6MPa / 1.0MPa / 1.6MPa |
|
Flange Standard |
GB/T 9119 (Chinese Standard) / ANSI B16.5 (American Standard) |
|
Material Grade |
PE80 / PE100 |
2. Quality inspection standards
Appearance inspection: No pores or burrs on the flange surface, no scratches on the HDPE pipe body.
Performance test:
Hydrostatic strength (no cracks at 20℃/100h)
Flange sealing test (no leakage at 1.1 times PN pressure)
Certification requirements: ISO 4427, GB/T 13663 certification is required.
1. Flange interface leakage
Reason: Gasket aging/bolt loosening/uneven flange surface.
Solution: Replace gasket, recalibrate torque, grind flange surface.
2. Pipe body deformation
Reason: Overpressure operation under high temperature environment.
Solution: Select PE-RT high temperature resistant material or add support frame.
HDPE Pipe with Flange has become the preferred solution for modern industrial and municipal pipeline systems by combining the corrosion resistance of plastic pipes and the reliability of flange connections. With the advancement of material technology and connection technology, its application field will be further expanded to harsh working conditions such as high pressure and high temperature. Correct selection, standardized installation and regular maintenance are the key to ensuring the long-term stable operation of the system.
