Permalok Steel Casing Pipe

Permalok® steel casing pipe employs a press-fit interlocking connection system that joins pipe sections together quicker than any other system in the field.

Permalok® Steel Casing Pipe excels in trenchless jacking construction applications including microtunneling and pipe jacking, auger boring, pipe ramming, and others. Our precision machined joint reduces field time by eliminating butt-weld joints, resulting is a shortened tunneling duration and reduced field costs.

In addition to significantly increasing field productivity, Permalok offers the strength and durability of steel piping with a variety of coating options. Permalok® stands as the product of choice for trenchless contractors and engineers for their most important and challenging projects.



Permalok® steel casing pipe dramatically increases field installation efficiency in trenchless projects. Our engineered steel pipe system utilizes a proprietary interlocking joint system that connects pipe quickly and eliminates field butt-welding.



Delivered to your jobsite with an integrated interlocking joint, Permalok® steel casing pipe eliminates time-intensive field butt welds in trenchless pipe installation projects. The precision-machined interface is flush with the interior and exterior surfaces of the pipe for quick alignment and connection. Combined with the use of a silicone sealant, the Permalok joint is leak resistant under the most challenging conditions.

Efficiency Comparison


Selecting Permalok® casing pipe over field-welded pipe provides an advantage you can take to the bank. Our proprietary airtight joints seal within minutes, compared to hours reserved for joint welding. The below examples demonstrate real savings in time and money in trenchless installations.

Unmatched Quality

Northwest Pipe is committed to providing quality products and services for our customers.