Why Line Water Pipe at All
Steel water pipe is strong but wants to rust; cement-mortar lining solves it cheaply. A centrifugally cast mortar layer isolates the steel from the water, raises pH at the wall (passivating), and provides a smooth hydraulic surface. It is the workhorse lining for transmission mains under AWWA C205 (lining) and AWWA C200 (the steel pipe itself), with buried-corrosion protection on the outside under C214 tape or C215? epoxy systems per project spec.
The Lining Process
Pipe sections are spun while a measured mortar charge is distributed, then troweled to a uniform bore; field joints are lined by hand after gasketing/welding. Standard thickness scales with diameter — commonly from about 6 mm on small bores to 13 mm on large transmission sizes — cured by moist curing or steam. Cement type (Type II/V, sulfate-resistant) follows the water chemistry.
| Diameter (DN) | Typical Lining Thickness | Notes |
|---|---|---|
| ≤ 300 | ≈ 6 mm | Shop-lined, gasket joints |
| 350–800 | ≈ 8–10 mm | Most transmission mains |
| ≥ 900 | ≈ 10–13 mm | Trowel finish, field joint lining |
Why Buyers Keep Specifying It
Three practical reasons: hydraulics — a smooth mortar bore keeps a Hazen-Williams C around 140 for decades; self-healing — minor cracks re-seal in water by autogenous healing; cost — lining adds little to steel pipe cost compared with alternatives, and repairs in-situ are straightforward. For potable systems, confirm the mortar and seal coat carry the required local approvals (e.g. NSF/ANSI 61 or equivalent).
Frequently Asked Questions
Does the lining crack?
Hairline shrinkage cracks are normal and heal in service. Structural cracking or spalling from handling damage is not — that is what pre-dispatch inspection catches.
Can it be applied to old pipes?
Yes — in-situ rehabilitation of existing steel mains by slip-lining mortar is a standard renewal method and often beats replacement on cost.
What about seawater or aggressive water?
Sulfate-resistant cement and seal coats address aggressive chemistry; for very high chlorides, epoxy linings (AWWA C210 family) are the usual alternative. Match the lining to the water analysis, not to habit.
CREATEEL supplies AWWA C200/C205 cement-mortar lined steel pipe for water transmission, with potable-compliance documentation on request.
Standards & references: AWWA C200/C205 · NSF/ANSI 61
Need a quotation? CREATEEL supplies carbon steel, alloy and stainless pipes to API, ASTM and EN standards with EN 10204 3.1/3.2 certification. Contact us for a fast offer.
