FAQs
Cured-in-Place Pipe (CIPP) FAQs
How strong is a CIPP liner?
The strength of a CIPP liner is designed to match the needs of the application. Each liner can be designed as a “standalone pipe” to support the entire live load, dead load and groundwater pressure.
What pipe diameters work best with CIPP?
Spiniello has lined pipes with its CIPP technology in a wide range of diameters — from 8 inches to 108 inches.
What is done with the flow while the pipe is being lined?
The flow must be removed from the line by diverting it to another system or installing an above-ground bypass pumping system.
How long does it take to line a pipe?
The timing of a CIPP project varies, depending on the diameter, length and thickness of the pipe. Projects can range from 1 to 5 days.
How does the CIPP liner harden?
The CIPP liner is comprised of a non-woven, needled felt that is saturated with a thermo-setting resin. The resin is hardened by heating the water inside the liner.
Is digging involved with CIPP?
The only excavation that may be required is the opening of manholes to allow the insertion of a liner, larger than the existing manhole opening.
Can CIPP liners be designed for corrosion resistance only?
Yes, CIPP liners can be designed for a “non-deteriorated condition” — that is, a non-structural application that provides only corrosion resistance.
How is the CIPP liner inserted into a pipe?
The CIPP liners are inserted into each pipe through an existing manhole or access opening. Then, they are turned inside out or “inverted” with water pressure, extended to the termination manhole or opening, and heated until the liner has cured. After the lined pipe has cooled, the ends are opened for the return of the flow.
Cement Mortar Lining (CML) FAQs
Is there a CML process that is structural?
The CML itself can provide some structural benefits and prevent leakage. For pipeline projects involving significant load forces and internal pressures, reinforced CML is the ideal solution. Reinforced CML can be used on water mains 30 inches in diameter and larger.
What are the cost savings of CML?
CML typically costs less than 50% of replacement costs, and it has a life span of more than 75 years. As the pipe diameter increases, the proportion of savings also increases dramatically.
Is CML a proven process?
Yes, Spiniello completed its first in-place CML project in 1946. Plus, all new ductile iron pipe comes with a CML pre-installed at the factory.
Which has better quality: in-place CML or factory-installed CML?
In-place CML is superior to factory-installed CML because it is typically made with a one-to-one ratio of silica sand to cement. This makes the lining highly durable, with compressive strengths in excess of 7,500 psi. Factory linings typically only have a three-to-one ratio. Further, in-place linings are installed under optimum curing conditions, where water is introduced into the main about one day after the lining is applied. In addition, the in-place lining is applied centrifugally for maximum adherence.
Will the CML have to be replaced after a period of time?
Each CML application should last for more than 75 years — longer than the average lifespan of a water main. The only exception to this is in large-diameter lines that carry raw water at high velocities, where sand particles may scour the lining. This is a rare case, but studies show that it is still dramatically more economical to repair these linings every 25 years, rather than replace the pipelines.
Does CML provide a barrier to corrosion, or can it prevent corrosion?
CML is the perfect way to prevent corrosion within cast iron pipes. The CML maintains an alkali surface on the cast iron (or ductile iron) pipe that effectively prevents corrosion for as long as the lining remains in the pipe. This is much better than providing a "barrier to corrosion" — that is, a coating system that works as a barrier and tries to prevent corrosion by keeping moisture from coming into contact with the pipe.