Permalok Steel Casing Pipe

Specifications for Permalok® Pipe

steel pipes with internal bracing
AWWA ASTM A1097 and AWWA C200

Northwest Pipe Company manufactures Permalok® Casing Pipe to the specifications of your project and to the consensus standards set by ASTM or AWWA. We are a fully experienced, reputable, and qualified manufacture of steel pipe, casings and fittings. All pipe and fittings are designed and constructed in accordance with the best practices and comply with applicable specifications. Our pipe cylinders, coating, lining, and fabrication of specials are manufactured in ISO 9001:2000 certified facilities.



AWWA C200 and AWWA Steel Pipe Design Manual M11


Spiralweld and seam-weld steel pipe


Standard diameters of 12” to 150” in lengths of 3’ to 50’. Wall thickness 0.105” through 2.500”.


Permalok is most often used as a casing pipe. Permalok with a T-7 joint can be used as a carrier pipe in low- to medium-pressure applications.


Permalok T-5, Permalok T-7, Permalok Auger Bore AB Joint and Pipe Ramming.


Polyurethane, liquid epoxy, and specialty paints.


Polyurethane, liquid epoxy, and specialty paints.

Principle Uses

Casing pipe excels in trenchless applications including microtunneling, jacking, and auger boring. Often used under road and rail structures as well as under bodies of water to insulate carrier pipe. Also used as carrier pipe in low- to medium-pressure applications.

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