A metallic Zinc layer is applied by thermal metallization process on the DI pipe surface. The
metallic Zinc coating is covered by a finishing layer of a bituminous paint or synthetic resin
compatible with zinc. The International Standard ISO: 8179-1 establishes the main features of
Zinc coating as well as suitable methods for checking them.
Two options of Zinc coating are available, depending on soil aggressiveness –
Standard 130 gm/m2 and finishing layer of 70 microns
200 gm/m2 and finishing layer of 70 microns or 100 microns
Internal Protection System – Cement Mortar Lining
Normally, all pipes are supplied with centrifugally applied internal Cement Mortar Lining.
Centrifugally applied CML Provides higher Hazen William C Value of 140 minimum
Reduce frictional head loss and pumping cost
CML Passivates the pipe wall against corrosion by the alkaline reaction of cement
It prevents pitting and tuberculation of pipes and stops the production of red water
Helps to maintain same flow are and co-efficient of friction over a long period of time
