3N1 Boreable Conduit *patent pending

Blue Diamond has developed a new "Boreable" HDPE continuous conduit with 3 innerducts pre-installed inside.  The innerducts are installed at our manufacturing facility during the extrusion process.  It is a process similar to CIC (Cable in Conduit) where power or communication cables are typically installed during production.

Blue Diamond 3N1 saves time and money by allowing contractors to bore a complete package.  Innerducts do not have to be pulled through after the bore, allowing you to blow fiber or pull power cables as soon as the bore is complete.  With Blue Diamond's 3N1, innerducts won't get stuck or twisted during field installation.

  • 4" SIDR 11.5 casing with 3-1.25" SDR 13.5 innerducts
  • 4" SDR 13.5 casing with 3-1" SDR 13.5 innerducts
  • 4" SIDR 11.5 casing with 4-1" SDR 13.5 innerducts

Available lengths are 500' to 1000' on steel reels.

Although 3N1 is particularly suited to HDD (horizontal directional drilling), it can also be used for plowing along highways.

3N1 Boreable Conduit has 3 innerducts pre-installed, allowing blowing or pulling cable immediately after boring.

3N1 Couplers


To connect longer runs of 3N1, Blue Diamond and ETCO Specialty Products have developed a coupling system that pressure-seals the innerducts and provides a positive water-tight connection for the outer casing pipe.  The innerducts are connected using a 6" wide, dense polyurethane elastomer ribbed internal compression fitting.  The fitting can withstand 100 psi pressure, making it ideal for blowing fiber through the innerducts.  The 3N1 casing connector is a 12" long rigid PVC case with a ribbed polyurethane insert.  It opens as a clamshell to easily accomodate the HDPE casing in the field.  Five marine grade stainless steel clamps compress the polyurethane liner making the entire connection water-tight.  Stainless steel screws and clamps provide up to a 1000lb tensile pull strength for pull apart in a plow or trench application.  However, use of a coupler in a HDD boring application is still not recommended.

3N1 Coupler on Duct

A coupler can be used on HDPE that pressure seals the innerducts and provides a positive water-tight casing.

Empty 3N1 Casing

BDI 3N1 casing, a long PVC case with a ribbed polyurethane insert, opens like a clam shell to accommodate  HDPE casing.

Closed Fitting with Marine Grade Stainless Steel Clamps

Five marine grade stainless steel clamps compress the polyurethane line making the entire connection water tight.

Open Fitting with Polyurethane Insert and Innerduct

A Fitting with Polyurethane Insert and Innerduct provides a water-tight casing for fiber optic and power cables.