DUAL WALL CONTAINMENT HDPE PIPE

 

• HDPE DUAL WALL CONTAINENT PIPE SPECIFICATION
• IPS SIZE & DIMENSION DATA (PE4710) (pdf)
• PE3608/(PE3408) PIPE & FITTINGS DATA SHEET (pdf)
• PE4710/(PE3408) PIPE & FITTINGS DATA SHEET (pdf)
• DUAL CONTAINED FITTINGS

Dual wall containment pipe is made from two solid wall HDPE pipes. Also called the double wall HDPE pipe, the assembly consists of an inside pipe (Carrier Pipe) which is centered within an outer pipe (Containment Pipe) The containment pipe adds the protection of a second pipe to contain the fluids in the event that the carrier pipe should develop a leak. End spacers or centralizers are located at each end of the pipe. The end spacers center the carrier pipe inside of the containment pipe. They are designed to form a tight fit, holding the two pipes in place so they can be simultaneously welded to the next pipe. End centralizers are often extrusion welded in place to prevent pipes from slipping when being simultaneously butt fused together. Intermediate centralizers are placed at intermediate points specified by the engineer to provide additional support.

Increasing concern about damage from leaking pipes that could potentially cause damage to the environment or pollute the ground water, is causing more engineers, companies and regulators to consider using dual contained piping systems.

EXAMPLE OF DUAL CONTAINED PIPE
With centralizers per engineers Design
(CENTRALIZERS ARE NORMALLY 10 FEET APART).

EXAMPLE OF DUAL CONTAINED PIPE SUPPORTED ONLY AT THE ENDS
(UNSUPPORTED DUAL CONTAINED PIPE MAY BE VERY LONG IF CENTRAIZERS ARE NOT REQUIRED EXCEPT AT FUSION POINTS)

In some applications centralizers are only used where simultaneous fusion joints are made. This may only be every 100-200 feet. In this case 2 centralizers are used normally 6-8 inches apart to insure the pipe is lined up straight for the fusion joint.

Operating pressure capabilities for the carrier pipe and the containment pipe may be quite different. The containment pipe is normally open ended draining into a manhole or containment pond. As a result pressure for the containment pipe would rarely be very high.  In landfill applications it is common for the carrier pipe to be sdr 11 and the containment pipe to be sdr 17. Both pipes should be pressure rated to meet the requirements of the engineer.

Dual contained HDPE pipe is available in sizes up to 63 inches for the containment pipe and 54 inches for the carrier pipe.

In many cases the engineer may specify a leak detection system. The leak detection system can be low point monitoring in the containment pipe which would trigger an alarm, or in the case of highly sensitive fluids, the engineer may specify a continuous leak detection cable. This would be rare because of cost and the potential for false alarms due to small amounts of condensation.

Dual contained HDPE pipe is an excellent choice of materials. HDPE pipe is very chemical resistant. It has a long life well in excess of 50 years. Heat fused joints are as strong as the pipe itself, eliminating the single most frequent cause of leaks in most competitive pipe systems. It is very flexible and will move with unstable soils and will not crack or break. Many HDPE pipe systems have survived the soil shifting of the ground even in an earthquake. It does not rust or rot. It remains flexible even in temperatures below 100 degrees F. HDPE pipe has excellent flow factors reducing operating costs. It is extremely tough and will sustain substantial abuse normally without damage to the carrier or the containment pipe.

Fusion Support Services, LLC can pre-fabricate your dual contained HDPE piping system in our plant, saving installation time and cost. Our certified field technicians are available to join dual contained piping systems or train the customer’s personnel in joining procedures. Specialty fittings are available per the engineers design.

Special testing equipment is available to test both the carrier pipe and the containment pipe. Contact your Fusion Support Services representative for information on purchasing or renting this testing equipment.

HDPE DUAL WALL CONTAINENT PIPE SPECIFICATION

The pipe used to fabricate dual contained HDPE piping systems shall have a minimum cell classification according to  ASTM D3350 of 345464C. No pipe that does not meet this minimum specification shall be used in an HDPE dual contained piping system.

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DUAL CONTAINED FITTINGS

The following are individual pdf files.

• Two Segment 22.5° Elbow
• Two Segment 45° Elbow
• Two Segment 90° Elbow
• Three Segment 90° Elbow
• Cross
• TEE
• Access Tee
• Centralizer - Press Fit
• Centralizer - Loose Fit
• Concentric Reducer
• End Cap
• Fixed End Seal
• Floor Drain
• Lateral
• Lateral Cleanout
• Dual Contained Testing 1
• Dual Contained Testing 2
• Dual Contained Testing 3
• Dual Contained Testing 4
• Low Point Monitoring Station
• Monitoring Tee
• Dual Contained Valve Box
• Reducer Eccentric
• Water-Stop/Wall Anchor Ring