High Density Polyethylene Duct

Application
High Density Polyethylene Duct has been tested and proven under the most severe conditions.  From extreme temperatures to abrasive and high tension applications in underground installations, HDPE provides quality service and economy in a wide range of uses.  As a smooth and flexible duct for cable, HDPE is unequaled for ease of installation and continuous strength.

Description
The duct shall be manufactured from virgin high density polyethylene. The addition of clean rework material is permissible if generated in the manufacturer’s own plant. The ducts are supplied with either smooth, ribbed, or corrugated walls and come in a multitude of colors. The duct shall be capable of being coiled (reeled) in continuous lengths, transported, stored outdoors and subsequently uncoiled for installation - without affecting its properties or performance.

Environmental Performance
The duct shall perform in underground and above-ground temperature range of minus 300° temperature range of minus 300°F to 1300°F without degradation of material properties. The duct specified for aerial installation shall be ultraviolet light-resistant. It shall be possible to bend the duct to a minimum (supported) radius of 10 diameters. Workmanship The duct shall be free of visible cracks, holes or other physical defects that would degrade its performance. It shall be as uniform as practicable in respect to overall dimensions, color, density, thickness, etc.

Color
The duct for exposed areas (black) shall have a minimum of carbon black. All other colors shall have a UV light stabilizer which will protect the duct for a minimum of 12 months in direct sunlight.

Markings
The duct shall have a durable identification showing the name or trademark of the manufacturer, duct size (i.e., 2” IPS SCH-80), date and reference code. Duct for electrical cable should have “CAUTION - HIGH-VOLTAGE” printed at regular intervals. Other special markings can be agreed upon between the buyer and seller.

Capping
The open ends of each length of reeled duct shall be sealed by plastic caps to prevent the entrance of dirt and/o r moisture.

Pull Rope and Lubricant
The duct should be equipped with a factory installed rope or tape and pre-lubed to aid in the installation of cable. The rope can be provided with varying strengths as needed for a particular installation. Check with a manufacturer for specifications.

Couplings
Couplings should be available to quickly connect the duct and should be air and watertight (i.e., Duct-Lok type couplings in either plastic or aluminum, depending on type of installation). Packaging The duct should be provided on lightweight metal reels in maximum lengths possible with no joints or splices. This will keep coupling requirements to a minimum. Special reel sizes and/ or dimensions should be available for special installations.

Corrosion
The duct shall be resistant to most harsh chemicals and/or protected against degradation due to oxidation or general corrosion.

Installation
The duct shall be capable of being direct buried by plowing or trenching with no special consideration to using selective backfill. The duct shall also be capable of being encased in concrete.

NOTE:  HDPE conduit is manufactured to the dimension and requirements of ASTM F2160. Ovality (out-of-roundness) and curvature are inherent characteristics of coiled, continuous length HDPE conduit. While these conditions are normal and expected and are not a concern in most applications, some installations or applications may require “re-rounding” of the conduit. When this is necessary, ovality should be corrected in the field by processing the conduit through re-rounding and straightening equipment during installation.

Tests on Resins and Finished Duct

Since specifications vary from customer to customer, we perform in-house lab tests on resins and finished products which include, but are not limited to the following: 

• ASTM D3035: Polyethylene Plastic Pipe Based on Controlled Outside Diameter.
• ASTM D2447: Polyethylene Plastic Pipe, Schedules 40
• ASTM D2239: Polyethylene Plastic Pipe Based on Controlled Inside Diameter.
• ASTM D1248: Polyethylene Plastics Molding and Extrusion Materials. (Type III, Class A, B,or C, Category 5, Grade P34).
• ASTM D1693: Environmental Stress-Cracking of Ethylene Plastics. (Cond. B, F20/96 HRS.)
• ASTM D1238: Flow Rates of Thermoplastics by Extrusion Plastometer.
• ASTM D1505: Density of Plastics by the Density Gradient Technique.
• ASTM D638: Tensile Properties of Plastics.
• ASTM D3350: Polyethylene Plastic Pipe and Fittings Materials. (Cell # 335440).
• NEMA TC 7: Smooth-Wall Coilable Polyethylene Electrical Plastic Duct. Other ASTM tests i.e.: Tensile, Impact etc.
• ASTM D1505: Density of Plastics by the Density Gradient Technique.
• ASTM D638: Tensile Properties of Plastics.
• ASTM D2412: Determination of External Loading Characteristics of Plastic Pipe by Parallel-Plate Loading.
• ASTM D2444: Determination of the Impact resistance of Thermoplastic Pipe and Fittings by Means of a Tup.
• ASTM D3485: Smooth-Wall Coilable Polyethylene Conduit for Pre-assembled Wire and Cable.
• ASTM F2160: Standard Specifications for Solid Wall High Density Polyethylene (HDPE) Conduit Based on Controlled Outside Diameter (OD).

Design Considerations

Please refer to our technical data brochure. This shows different design parameters for polyethylene pipe (i.e., Wall Crushings, Wall Buckling, etc.) as per the various SDR (wall thickness) ratings.

Special Options

Striped Duct - Three longitudinal stripes can be extruded on any standard size of smooth duct of any color.  Stripes are approximately 1/8-inch in width (varying slightly according to the duct size). There is no additional charge for Striped Duct.

Sequentially-Marked Duct - Duct can be ordered with numbering - every two feet - printed on the duct.