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Sliplining: Host pipe=24" ID CCP and want slipline with 22"IPS HDPE DR11 pipe.

Sliplining: Host pipe=24" ID CCP and want slipline with 22"IPS HDPE DR11 pipe.

Sliplining: Host pipe=24" ID CCP and want slipline with 22"IPS HDPE DR11 pipe.

(OP)
I have 5 miles of 70-yr old concrete cylinder pipe (CCP) that has reached its design life. It is a raw(river)water pipeline laid on a uniform grade with drain and air vent valves placed at low and high points. Hydraulic analysis indicates a 22"IPS (17.75 ID) will satisfy our need with the reduced flows anticipated. I am calculating the maximum tension for pulling, with provisions to push pipe as well. I have four questions,
Q-1: Is a 1" annular space enough room to install the HDPE pipe? with or without casing spacers??
Q-2: What is the longest achievable pull distance that can be made given a relatively uniform grade?
Q-3: Video records of the existing pipe interior during pipe repairs show evidence of spalling and a organic film build-up with clam shells scattered throughout. Is there a good mechanical sweeper-device that can sweep the debris out, avoiding a high volume flush of water.
Q-4: Should the annular space be grouted when pipe slip-lining is completed?

RE: Sliplining: Host pipe=24" ID CCP and want slipline with 22"IPS HDPE DR11 pipe.

Why don't you call the slip lining companies? They'll give you all that information and more for just hearing about the project.

RE: Sliplining: Host pipe=24" ID CCP and want slipline with 22"IPS HDPE DR11 pipe.

You can use a rotating chain flail or scrapers to clean it. Are there many bends in the line? What is the operating pressure and depth of burial?

Richard A. Cornelius, P.E.
WWW.amlinereast.com

RE: Sliplining: Host pipe=24" ID CCP and want slipline with 22"IPS HDPE DR11 pipe.

See spomehting like this http://water.epa.gov/scitech/wastetech/upload/2002...

They quote about 1000m / 3,000ft for an inverted (U shape) pull through which I what I would recommend. Gets away from most of the issues about potential gunge and small intrusions into your sleeve.

The issue is probably going to be how long can you lay out your pipe in a single length before you pull it in. With U shape and use of strengthening tapes and cables, you might be able to go to 1500m or more, but only dead straight. insertion rates eem quite low (50m/hr is quoted in one site)

If you don't need to grout (doesn't sound like you need to to me, then don't. A real pain in the ass and difficult to do uniformly and over the whole surface area.

Have you considered spray lining from the inside?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Sliplining: Host pipe=24" ID CCP and want slipline with 22"IPS HDPE DR11 pipe.

The selection of a polyethylene liner should have an outside diameter 10% less than the inside diameter of the pipe to be rehabilitated. It should work, but it will be tight.

Individual pulling lengths are usually determined by naturally occurring changes in grade or direction of the existing pipe system. Severe changes in direction that exceed the minimum recommended bending radius of the polyethylene liner may be
used as access points. Likewise, severe offset joints, as revealed during the television survey, are commonly used as access points. By judicious planning, potential obstructions to the lining procedure may be used to an advantage.

There is a frequent question regarding the maximum pulling length for a given system. Ideally, each pull should be as long as economically possible without exceeding the tensile strength of the polyethylene material. It is rare that a pull of
this magnitude is ever attempted. As a matter of practicality, pulling lengths aremore often restricted by physical considerations at the job site or by equipment limitations.(23)

To ensure a satisfactory installation, the designer may want to analyze what is considered the maximum pulling length for a given situation. Maximum pulling length is a function of the tensile strength and weight of the polyethylene liner, the
temperature at which the liner will be manipulated, the physical dimensions of the liner, and the frictional drag along the length of the polyethylene pipe liner.

https://plasticpipe.org/pdf/chapter11.pdf

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