External and internal coatings ensure the long life of steel water main pipes.
SSAB delivers water main pipes with external polyethylene coating and an internal concrete or epoxy layer suitable for use with drinking water. There are also suitable inside coatings for sewage and rainwater.
External coating
| Property | Typical values | |
| Density grade | HDPE (High density Polyethene) | |
| Thickness, mm | > 2,2 | DN 400 - 450 |
| > 2,5 | DN 500 - 750 | |
| > 3,0 | DN 800 - 1200 | |
| Increased thickness (v) + 0,7 | ||
| Bond strenght at +20 ⁰C, N/cm | > 120 | |
| Impact resistance, J/mm | > 5 | |
| Identation at +23 ⁰C, mm | 0,2 > | |
| Breaking elongation, % | > 400 | |
| Specific resistance, Ωm2 | > 108 | |
| Thermal ageing, % | 35 > | |
| Light ageing, % | 35 > | |
| Cathodic disbonding, 30 days, mm | 5 > | |
| Ambient temperature, ⁰C | - 40 ... +80 |
The 3-layer coating consists of polyethylene, adhesion and epoxy layers.
Internal cement mortal lining
| Property | Typical values |
| Thickness, mm | 8 ± 2 DN 400 - 600 |
| 10± 3 DN 650 - 900 | |
| 12± 3 DN 950 - 1200 | |
| Flexural tensile strength, N/mm2 | > 5 |
| Compressive strength, N/mm2 | > 50 |