Slip Lining in Philadelphia, PA and the Nearby Areas

For larger pipes from 12″ to 72″ in diameter, slip lining is an option. Slip lining is installing a new but smaller pipe through an old one. The most typical examples are old corrugated metal pipe (CMP) storm lines that have rusted through on the bottom. Sometimes they also rust through on the top and create sinkholes above where the soil is dropping into the old CMP. Because so much of the original pipe’s integrity is lost, it is a better solution to slide a new pipe through the old. There can be several different materials used for slip lining in Philadelphia, PA area but the most common materials include high-density polyethylene (HDPE), PVC, and fiberglass-reinforced pipe.

We commonly serve the following areas:

• Philadelphia, PA suburbs
• Bryn Mawr, PA
• West Chester, PA
• Paoli, PA
• Ardmore, PA
• Berwyn, PA
• Devon, PA
• Harrisburg, PA
• Hershey, PA
• Lancaster, PA
• Lower Merion Township, PA
• Pottstown, PA
• Reading, PA
• Villanova, PA
• Wayne, PA

A New Pipe Is Put in Place of the Older Pipe

The new carrier pipe does have a smaller ID than the original host pipe. However, the better flow characteristics of the new pipe can often accommodate much of the flow capacity of the old pipe. In the case of a new HDPE pipe slip lined into an old CMP line, the new smaller pipe often has a larger flow capacity than the original CMP due to its better flow characteristics. Depending on the access, the new piping can be fused HDPE which is then pulled into place in one operation, or the new pipe can be sectional with snap-together ends. In the sectional approach each additional piece of pipe can be lowered into a trench, snap connected to the previous piece, and then the assembled pipe pushed further into the old pipe. Then another pipe section is lowered into the trench and the process is repeated until the old pipe is completely slip lined. This allows for less disturbance when the old pipe is fairly deep and so an adequate sloping entry trench to accommodate an assembled pipe would be too much excavation.

The Space Between the Carrier and Host Pipe Is Grouted

After the new carrier pipe is installed there is still an annular space between the old and new pipes. This space should be filled with a grout that mimics the characteristics of soil. This grouting helps lock the new pipe into place, removes an alternate path for water to flow around the new pipe instead of through it, and it beds the new pipe to give it the haunch support it should have to retain its shape.

Choosing the Proper Grout Is Crucial

Selecting the proper grout and installing it correctly is critical. The grout needs to flow easily enough to fill in all the spaces while staying below a specified minimum pressure. That pressure minimum is especially critical if the new carrier pipe is of a snap-connection type instead of a fused joint construction. The snap-connection joints can buckle under relatively low grouting pressure causing the grout to flow into the pipe and possibly into a waterway at the end of the pipe, creating a real mess under the best of conditions. So always go for minimal pressure with the grout.

To learn more about slip lining and the types of projects that this trenchless rehabilitation method can be used on, talk to a professional at Pipeshark today by calling 610-993-9300. You can also ask us about the wide range of plumbing services in Philadelphia, PA that we offer.

Contact our trusted pipe lining company today or fill out our online form to schedule an appointment with our reliable plumber in Philadelphia, PA.