Cement* Mortar Lining
Cement Mortar Lining with Bituminous Seal Coat
Cement Mortar Lining with Epoxy Seal Coat
*Cement Type: OPC/ Sulphate Resistant Cement/ Blast Furnace Slag Cement / High Alumina Cement
Zinc Coating (130 gm/m2 or 200 gm/m2 or 400 gm/m2) with finishing layer of Bitumen/ Blue Epoxy/ Red Epoxy
Polyethylene Sleeving
Alloy of Zinc and Aluminum with or without other metals having a minimum mass of 400 gm/m2 with finishing layer of Bitumen/Blue Epoxy/Red Epoxy
Bitumen; Epoxy; Polyurethane.
IS 8329 ; ISO 2531 : ISO 7186 ; BS EN 545 ; BS EN 598
British Standards Institute and DNV
British Standards Institute and Bureau Veritas
Note:
Currently Class K9 and Class 40 pipes are being manufactured and supplied. Other classes will be offered in the near future.
Ductile Iron Pipes installed in water systems today are normally provided with cement mortar lining. Use of cement lining of the pipe avoids tuberculation by creating a high pH at the pipe wall, and ultimately by providing a physical barrier to the flow water to contact with the pipe wall. Further, linings are also smooth, which results in high coefficients with Haizen Willams C as 140 (Colebrook coefficient k = 0.1). In case of sewerage application, suitable lining will provide corrosive resistance to septic transformation (cycle of sulphates, sulphuric acid) to avoid severe carrion to pipe wall. The advantages of internal cement mortar lining are:
- Internal protection of pipe wall against fluid aggressiveness
- Improvement and performance of pipe flow characteristics
- For potable water pipelines, assurance of keeping water quality within specified limits.
- Withstand against corrosion due to septic transformations.
Intrinsic corrosion resistance of Ductile Iron in various corrosive soils is as least as good as and even somewhat better than that of Cast Iron, as there is not much variation chemically between the two materials. When subjected to corrosion, the nodular graphite of ductile iron pipes forms corrosion by products that adhere firmly to the unattached metal, which provides a barrier against further corrosion. In addition, uniform spreading of spheroidal graphite of ductile iron results in less susceptible to deep localized pitting than that of grey iron pipe, which is important in evaluating its relative resistance to failure by perforation. Due to rubber gasket jointing, ductile pipes are electrically discontinuous. As a result, long line corrosion current, which is dependent on exposure of a single electrical unit to varying soil conditions, can not develop. Additionally, any accumulation of stray current is limited to short electrical units and usually is of little significance in developing corrosion.
Additional external protection to ductile iron pipe provides long service performance, especially for smaller diameter pipes where wall thickness is comparatively less. Following external protection is normally being provided:-
