Rehabilitation of metal pipes for water supply – cement mortar lining

The Cement Mortar Lining Relining is a technique already adopted by many years in the United States and in many European countries, for its effectiveness and for its cheapness.

This technique is generally used to rehabilitate metal pipes (cast iron and steel) and consists in the application, the pipe walls to heal (host pipe), of a high-speed layer of cement mortar projected by a machine (lining machine) equipped with a rotating head (spinning head), followed by a mechanical smoothing system (conical trowel for small diameters, the rotating spatulas for larger diameters).

Before treatment, the pipe section to be repaired is isolated, and through careful visual inspection and the taking of samples, it evaluates its internal state, to be able to choose the thickness of the mortar layer thickness, which also varies as a function diameter and operating pressure (the thickness ranges from 4 to 14 mm).

Immediately after we proceed with the cleaning of the pipe to achieve a clean metal surface which ensures a good adhesion of the mortar, after which it can proceed with the treatment.

The advantages of this technique are numerous:

Low costs (the CML is currently the most economical technique for repairing pipes for water) relining14
semi-structural restoration and hydraulic piping (withstands high pressures and restores the structural characteristics of the host pipe – high shear strength)
Improvement in the roughness of the pipe wall (after smoothing are achieved excellent roughness values ​​that are stable over time)
Long life (coating that guarantees a lifetime of over 50 years)
Short processing times (with a consequent reduction of discomfort).

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